MD 0644 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR NORTHEAST OK INTO NORTHWEST AR AND FAR SOUTHWEST MO
Mesoscale Discussion 0644
NWS Storm Prediction Center Norman OK
0101 AM CDT Tue May 05 2026
Areas affected...Northeast OK into northwest AR and far southwest MO
Concerning...Severe potential...Watch unlikely
Valid 050601Z - 050800Z
Probability of Watch Issuance...20 percent
SUMMARY...Strong to locally severe storms will remain possible
overnight.
DISCUSSION...An elevated storm cluster has recently shown some signs
of organization across northeast OK, with convection increasing
along both a developing cold pool and gust front, and within a warm
advection regime near the OK/MO/AR border region. This cluster is
being aided by a strong low-level jet, which should help to maintain
this cluster as it moves southeastward overnight.
Steep midlevel lapse rates (as observed on regional 00Z soundings),
MUCAPE of near/above 1000 J/kg, and moderate effective shear will
support some hail potential with the strongest embedded updrafts,
though the ongoing cluster/linear mode may mitigate hail potential
to some extent. Severe wind potential is also uncertain, due to the
elevated nature of the ongoing convection. However, given the
presence of a surface cold pool and sharp pressure rises (2-3
mb/hour) behind the gust front noted on Mesonet observations in
northeast OK, locally damaging wind could also accompany this system
as it moves southeastward.
..Dean/Mosier.. 05/05/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LZK...SGF...TSA...ICT...
LAT...LON 37099541 36769396 36279245 35969268 35609313 35379404
35729464 36029506 36249525 36699553 37099541
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
Read more
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1257 AM CDT Tue May 05 2026
Valid 061200Z - 071200Z
...NO CRITICAL AREAS...
...Synopsis...
An elongated upper-level trough deepens across the Great Lakes into
the Southwest Wednesday, with a broad corridor of stronger mid-level
winds over the Southern Plains. A related cold front stretching
southwestward from the Northeast into TX gradually advances east
through Wednesday afternoon before a marked southward acceleration
takes place overnight across TX. A drying and warming trend
commences Wednesday across the Intermountain West as an upper ridge
pushes into the West Coast.
...Southern New Mexico into West Texas...
Stronger mid-level flow will linger across portions of the Southwest
and TX as a more robust jet core of 75-80 knots shifts into the OH
River Valley. Stronger westerly winds of 15-25 mph south of an
advancing cold front over the TX Panhandle and enhanced downslope
drying should yield 15% RH or less across much of southern NM into
West TX. However, recent rainfall has moderated fuels across this
region, mitigating the overall fire weather threat.
..Williams.. 05/05/2026
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1257 AM CDT Tue May 05 2026
Valid 061200Z - 071200Z
...NO CRITICAL AREAS...
...Synopsis...
An elongated upper-level trough deepens across the Great Lakes into
the Southwest Wednesday, with a broad corridor of stronger mid-level
winds over the Southern Plains. A related cold front stretching
southwestward from the Northeast into TX gradually advances east
through Wednesday afternoon before a marked southward acceleration
takes place overnight across TX. A drying and warming trend
commences Wednesday across the Intermountain West as an upper ridge
pushes into the West Coast.
...Southern New Mexico into West Texas...
Stronger mid-level flow will linger across portions of the Southwest
and TX as a more robust jet core of 75-80 knots shifts into the OH
River Valley. Stronger westerly winds of 15-25 mph south of an
advancing cold front over the TX Panhandle and enhanced downslope
drying should yield 15% RH or less across much of southern NM into
West TX. However, recent rainfall has moderated fuels across this
region, mitigating the overall fire weather threat.
..Williams.. 05/05/2026
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1257 AM CDT Tue May 05 2026
Valid 061200Z - 071200Z
...NO CRITICAL AREAS...
...Synopsis...
An elongated upper-level trough deepens across the Great Lakes into
the Southwest Wednesday, with a broad corridor of stronger mid-level
winds over the Southern Plains. A related cold front stretching
southwestward from the Northeast into TX gradually advances east
through Wednesday afternoon before a marked southward acceleration
takes place overnight across TX. A drying and warming trend
commences Wednesday across the Intermountain West as an upper ridge
pushes into the West Coast.
...Southern New Mexico into West Texas...
Stronger mid-level flow will linger across portions of the Southwest
and TX as a more robust jet core of 75-80 knots shifts into the OH
River Valley. Stronger westerly winds of 15-25 mph south of an
advancing cold front over the TX Panhandle and enhanced downslope
drying should yield 15% RH or less across much of southern NM into
West TX. However, recent rainfall has moderated fuels across this
region, mitigating the overall fire weather threat.
..Williams.. 05/05/2026
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1255 AM CDT Tue May 05 2026
Valid 051200Z - 061200Z
...Synopsis...
Stronger southwesterly flow aloft ahead of an advancing upper-level
trough will move into the Southern Plains through today. A cold
front trailing behind an elongated surface low over OK should stall
across the TX Panhandle and just south of the Red River Valley this
afternoon. Farther east, a deepening upper trough over Ontario and
Quebec and associated increasing southwesterly mid-level flow will
encroach into the Northeast today. At the surface, drier pre-frontal
southwest flow will affect much of the Mid Atlantic and Northeast.
...Mid Atlantic...
Dry, southerly to southwesterly flow ahead of an eastward moving
cold front across the OH River Valley is expected across the Mid
Atlantic today. Limited boundary layer moisture, leading to RH
reductions of 20-30%, and sustained south/southwest winds of around
15 mph with higher gusts will evolve by mid-afternoon in the
Carolinas and Mid Atlantic. A zone of minimal rainfall has resulted
in lingering fuel dryness across northern NC into much of central
and eastern VA. Elevated fire weather highlights where added to the
aforementioned area where most likely alignment of dry and breezy
conditions and dry fuels exist.
...West Texas...
A 60-65 knot mid-level jet in advance of an upper trough will eject
into the Southern Plains today. A cold front will stall across the
northwest TX, inhibiting dry, downslope enhanced westerly flow from
aligning with the more receptive fuels across the eastern TX
Panhandle into southwestern KS. Breezy west winds of 15-25 mph amid
relative humidity of around 15% are still expected across much of
west TX. However, recent wetting rainfall in the region has
mitigated the overall fuelscape, limiting impact from an otherwise
elevated fire weather threat.
..Williams.. 05/05/2026
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1255 AM CDT Tue May 05 2026
Valid 051200Z - 061200Z
...Synopsis...
Stronger southwesterly flow aloft ahead of an advancing upper-level
trough will move into the Southern Plains through today. A cold
front trailing behind an elongated surface low over OK should stall
across the TX Panhandle and just south of the Red River Valley this
afternoon. Farther east, a deepening upper trough over Ontario and
Quebec and associated increasing southwesterly mid-level flow will
encroach into the Northeast today. At the surface, drier pre-frontal
southwest flow will affect much of the Mid Atlantic and Northeast.
...Mid Atlantic...
Dry, southerly to southwesterly flow ahead of an eastward moving
cold front across the OH River Valley is expected across the Mid
Atlantic today. Limited boundary layer moisture, leading to RH
reductions of 20-30%, and sustained south/southwest winds of around
15 mph with higher gusts will evolve by mid-afternoon in the
Carolinas and Mid Atlantic. A zone of minimal rainfall has resulted
in lingering fuel dryness across northern NC into much of central
and eastern VA. Elevated fire weather highlights where added to the
aforementioned area where most likely alignment of dry and breezy
conditions and dry fuels exist.
...West Texas...
A 60-65 knot mid-level jet in advance of an upper trough will eject
into the Southern Plains today. A cold front will stall across the
northwest TX, inhibiting dry, downslope enhanced westerly flow from
aligning with the more receptive fuels across the eastern TX
Panhandle into southwestern KS. Breezy west winds of 15-25 mph amid
relative humidity of around 15% are still expected across much of
west TX. However, recent wetting rainfall in the region has
mitigated the overall fuelscape, limiting impact from an otherwise
elevated fire weather threat.
..Williams.. 05/05/2026
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1255 AM CDT Tue May 05 2026
Valid 051200Z - 061200Z
...Synopsis...
Stronger southwesterly flow aloft ahead of an advancing upper-level
trough will move into the Southern Plains through today. A cold
front trailing behind an elongated surface low over OK should stall
across the TX Panhandle and just south of the Red River Valley this
afternoon. Farther east, a deepening upper trough over Ontario and
Quebec and associated increasing southwesterly mid-level flow will
encroach into the Northeast today. At the surface, drier pre-frontal
southwest flow will affect much of the Mid Atlantic and Northeast.
...Mid Atlantic...
Dry, southerly to southwesterly flow ahead of an eastward moving
cold front across the OH River Valley is expected across the Mid
Atlantic today. Limited boundary layer moisture, leading to RH
reductions of 20-30%, and sustained south/southwest winds of around
15 mph with higher gusts will evolve by mid-afternoon in the
Carolinas and Mid Atlantic. A zone of minimal rainfall has resulted
in lingering fuel dryness across northern NC into much of central
and eastern VA. Elevated fire weather highlights where added to the
aforementioned area where most likely alignment of dry and breezy
conditions and dry fuels exist.
...West Texas...
A 60-65 knot mid-level jet in advance of an upper trough will eject
into the Southern Plains today. A cold front will stall across the
northwest TX, inhibiting dry, downslope enhanced westerly flow from
aligning with the more receptive fuels across the eastern TX
Panhandle into southwestern KS. Breezy west winds of 15-25 mph amid
relative humidity of around 15% are still expected across much of
west TX. However, recent wetting rainfall in the region has
mitigated the overall fuelscape, limiting impact from an otherwise
elevated fire weather threat.
..Williams.. 05/05/2026
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1207 AM CDT Tue May 05 2026
Valid 061200Z - 071200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHEAST TX
TO THE LOWER MS AND TN VALLEYS...
...SUMMARY...
Scattered strong to severe thunderstorms are expected Wednesday
afternoon and evening across portions of Texas into the lower
Mississippi and Tennessee Valleys/southern Appalachians. Damaging
winds, large hail, and a couple of tornadoes will be possible.
...Synopsis...
A positive-tilt large-scale upper trough will extend from the Upper
Great Lakes to the Southwest early Wednesday. The southern extent of
the trough will develop east toward the southern High Plains to
northwest Mexico by Thursday morning. Strong mid/upper southwesterly
flow ahead of the trough will overspread much of the southern and
eastern U.S. At the surface, a cold front will extend from the upper
Ohio Valley to central TX during the morning. The front is expected
to develop south/southeast through the period, becoming oriented
from the southern Mid-Atlantic to South TX by Thursday morning.
Ahead of the front, rich Gulf moisture will be in place across TX
into the Lower MS and TN Valleys, decreasing with northeast extent
into parts of the southern Appalachians.
...Northern TN Valley and southern Appalachians...
Forecast guidance varies, but some showers/thunderstorms may be
ongoing Wednesday morning across parts of AR into northern parts of
the TN Valley within a warm advection regime on the nose a gradually
weakening low-level jet. This activity will likely play some role in
destabilization later in the day across parts of the TN Valley into
the southern Appalachians vicinity. Nevertheless, strong deep-layer
shear and a moist boundary layer will be sufficient for at least
some severe risk, including damaging wind gusts and perhaps hail.
Some tornado risk could also materialize given favorable low-level
shear and 0-1 km SRH increasing to greater than 250 m2/s2 during the
afternoon/evening. However, this is less certain given
aforementioned instability issues and later storm timing into the
southern Appalachians.
...TX to MS/AL...
Further south from northeast TX into MS/AL, strong destabilization
is forecast where deep boundary layer moisture and stronger daytime
heating occurs. MLCAPE in the 2000-3000 J/kg range appear possible
in particular across northern LA into MS. Midlevel southwesterly
flow is expected to increase by late afternoon into the evening as
early capping will be overcome as the surface front begins to
develop south/southeast. Convection along the cold front may quickly
transition to linear/bowing segments given deep shear parallel to
the surface boundary. However, low-level flow in latest model
guidance does not appear to be overly veered, especially near
northern LA into MS. Forecast hodographs indicate enlarged,
favorably curved hodographs across this area. If open warm sector
supercells develop, a risk for tornadoes (perhaps a couple strong
tornadoes) will be possible. Furthermore, steepening midlevel lapse
rates are evident in forecast soundings, along with
elongated/straight hodographs and 45+ kt effective shear magnitudes.
This indicates any semi-discrete supercells could pose a risk for
large to very large hail. With time during the evening/nighttime
hours, convection should generally congeal into a line or bowing MCS
and spread eastward across the TN Valley toward the southern
Appalachians, posing a risk for damaging gusts. Higher tornado and
hail probabilities were considered across parts of the Lower MS
Valley, however, given uncertainty in storm mode and coverage of
discrete supercells, will hold at level 2 (Slight) risk for now.
Across portions of central TX overnight, some guidance suggests
convection may develop within low-level warm advection as the
western extent of the surface cold front dives southward across the
Edward Plateau vicinity. If storms develop, they would likely be
elevated. Nevertheless, a hail risk could materialize within the
conditional scenario late in the forecast period.
..Leitman.. 05/05/2026
Read more
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1207 AM CDT Tue May 05 2026
Valid 061200Z - 071200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHEAST TX
TO THE LOWER MS AND TN VALLEYS...
...SUMMARY...
Scattered strong to severe thunderstorms are expected Wednesday
afternoon and evening across portions of Texas into the lower
Mississippi and Tennessee Valleys/southern Appalachians. Damaging
winds, large hail, and a couple of tornadoes will be possible.
...Synopsis...
A positive-tilt large-scale upper trough will extend from the Upper
Great Lakes to the Southwest early Wednesday. The southern extent of
the trough will develop east toward the southern High Plains to
northwest Mexico by Thursday morning. Strong mid/upper southwesterly
flow ahead of the trough will overspread much of the southern and
eastern U.S. At the surface, a cold front will extend from the upper
Ohio Valley to central TX during the morning. The front is expected
to develop south/southeast through the period, becoming oriented
from the southern Mid-Atlantic to South TX by Thursday morning.
Ahead of the front, rich Gulf moisture will be in place across TX
into the Lower MS and TN Valleys, decreasing with northeast extent
into parts of the southern Appalachians.
...Northern TN Valley and southern Appalachians...
Forecast guidance varies, but some showers/thunderstorms may be
ongoing Wednesday morning across parts of AR into northern parts of
the TN Valley within a warm advection regime on the nose a gradually
weakening low-level jet. This activity will likely play some role in
destabilization later in the day across parts of the TN Valley into
the southern Appalachians vicinity. Nevertheless, strong deep-layer
shear and a moist boundary layer will be sufficient for at least
some severe risk, including damaging wind gusts and perhaps hail.
Some tornado risk could also materialize given favorable low-level
shear and 0-1 km SRH increasing to greater than 250 m2/s2 during the
afternoon/evening. However, this is less certain given
aforementioned instability issues and later storm timing into the
southern Appalachians.
...TX to MS/AL...
Further south from northeast TX into MS/AL, strong destabilization
is forecast where deep boundary layer moisture and stronger daytime
heating occurs. MLCAPE in the 2000-3000 J/kg range appear possible
in particular across northern LA into MS. Midlevel southwesterly
flow is expected to increase by late afternoon into the evening as
early capping will be overcome as the surface front begins to
develop south/southeast. Convection along the cold front may quickly
transition to linear/bowing segments given deep shear parallel to
the surface boundary. However, low-level flow in latest model
guidance does not appear to be overly veered, especially near
northern LA into MS. Forecast hodographs indicate enlarged,
favorably curved hodographs across this area. If open warm sector
supercells develop, a risk for tornadoes (perhaps a couple strong
tornadoes) will be possible. Furthermore, steepening midlevel lapse
rates are evident in forecast soundings, along with
elongated/straight hodographs and 45+ kt effective shear magnitudes.
This indicates any semi-discrete supercells could pose a risk for
large to very large hail. With time during the evening/nighttime
hours, convection should generally congeal into a line or bowing MCS
and spread eastward across the TN Valley toward the southern
Appalachians, posing a risk for damaging gusts. Higher tornado and
hail probabilities were considered across parts of the Lower MS
Valley, however, given uncertainty in storm mode and coverage of
discrete supercells, will hold at level 2 (Slight) risk for now.
Across portions of central TX overnight, some guidance suggests
convection may develop within low-level warm advection as the
western extent of the surface cold front dives southward across the
Edward Plateau vicinity. If storms develop, they would likely be
elevated. Nevertheless, a hail risk could materialize within the
conditional scenario late in the forecast period.
..Leitman.. 05/05/2026
Read more
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1236 AM CDT Tue May 05 2026
Valid 051200Z - 061200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS CENTERED OVER
ARKANSAS AND EXTENDING FROM NORTHEAST TEXAS INTO WESTERN
TENNESSEE...
...SUMMARY...
Widely scattered severe storms are possible Tuesday afternoon into
Tuesday night from northeast Texas into western Tennessee, with the
main threat centered over Arkansas. The strongest storms will be
capable of large hail, damaging winds, and a few tornadoes. More
isolated, strong to severe storms are possible across parts of the
Northeast.
...Synopsis...
A vigorous, mid-level low over Ontario this evening is forecast to
evolve into an open wave while translating east into Quebec on
Tuesday. An accompanying belt of strong, mid/upper-level winds will
overspread the lower Great Lakes and northern New England in tandem
with modest height falls related to a vorticity maximum pivoting
through the base of the parent system. Elsewhere, a mid-level low
currently along the CA coast is expected to weaken while shifting
through the lower-CO Valley to the vicinity of the Four Corners
region. A belt of 50-70 kt winds at 500 mb are forecast downstream
from that feature, extending from the southern Plains into the Mid
South on Tuesday afternoon into evening.
In the low levels, a cold front is expected to extend from southeast
Quebec through the OH and mid-MS Valleys to low pressure over OK
Tuesday morning. The northern extension of the boundary will move
into the lower Great Lakes and northern New England during the peak
of the diurnal heating cycle. The segment of the front across the
Ozarks and Ozark Plateau may be temporarily displaced to the south
Tuesday morning due to overnight thunderstorm activity. However by
afternoon, the front is expected to refocus in the vicinity of the
MO-AR border, ahead of a weakening surface low moving through
eastern OK into western AR. The western extension of the cold front
trailing the surface low is expected to advance southeast through
the Red River Valley.
...Northeast Texas into the southern Missouri and western
Tennessee...
As mentioned in the synopsis, a complex of thunderstorms may be
ongoing at the start of the forecast period across portions of MO
into northern AR. That activity is expected to shift east of the
area by late morning or early afternoon, with some lingering shower
and thunderstorm development occurring to the north of the front in
central MO. In the wake of the early-day convection, HREF cloud
forecasts indicate the potential for considerable high-level clouds
and pockets of thicker low-cloudiness, which could limit the
potential for stronger diabatic warming within the pre-frontal air
mass. Nonetheless, the presence of boundary-layer dewpoints in the
60s in conjunction with an elevated-mixed layer (EML) plume will
support a moderately unstable air mass by afternoon with MLCAPE of
1000-2000 J/kg.
Neutral to slight height rises are forecast in the mid levels during
the peak of the diurnal heating cycle with model forecast soundings
indicating considerable capping at the base of the EML. As such,
eventual storm coverage remains uncertain. The 00z high-resolution
models suggest that isolated to widely scattered thunderstorms will
become increasingly likely by late afternoon or early evening along
the frontal segment along the MO-AR border, immediately
east/northeast of the surface low. Additional, isolated storm
development also appears possible from the vicinity of the surface
low southwest along the cold front into northeast TX, mainly during
the evening hours.
The favorable overlap of moderate instability and strong deep-layer
shear will favor supercell storm modes, especially given the
anticipated weak forcing for ascent. Large hail will be the
predominant severe-weather hazard initially. A few tornadoes appear
possible across portions of northern AR, potentially into western TN
from late afternoon through the evening association with any
sustained supercells. Here, the presence of a 35-40 kt low-level jet
will yield effective SRH of 200-300 m2/s2 amidst a moist/low-LCL
environment. Storms may eventually grow upscale into clusters, at
which point damaging winds would become a growing concern.
...Lower Great Lakes into northern New England...
Moisture advection occurring along a southwesterly low-level jet
will allow dewpoints to rise into the 50s within the pre-frontal
warm sector on Tuesday. And while mid-level lapse rates are not
expected to be particularly steep, the moisture increase combined
with daytime heating and the resultant steepening of low-level lapse
rates will result in MLCAPE of 500 to perhaps 1000 J/kg. Increasing
height falls aloft and convergence/lift along the cold front are
expected to support surface-based storm development by early
afternoon within the destabilizing air mass across portions of
upstate NY. The storms will quickly overspread northern portions of
VT, NH, and ME during the afternoon into early evening.
The 00z high-resolution models indicate the potential for transient
supercell and bowing structures, which appears reasonable given the
presence of a relatively strong, deep-layer wind field. In that
scenario, isolated occurrences of damaging winds and perhaps some
marginally severe hail appear possible. The tornado threat will be
conditional on sufficient instability to support more sustained
supercell structures. A level 1/Marginal Risk will be maintained;
however, if it becomes apparent that stronger instability will
develop than is currently anticipated, an upgraded to level 2/Slight
Risk may become necessary.
..Mead/Lyons.. 05/05/2026
Read more
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1236 AM CDT Tue May 05 2026
Valid 051200Z - 061200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS CENTERED OVER
ARKANSAS AND EXTENDING FROM NORTHEAST TEXAS INTO WESTERN
TENNESSEE...
...SUMMARY...
Widely scattered severe storms are possible Tuesday afternoon into
Tuesday night from northeast Texas into western Tennessee, with the
main threat centered over Arkansas. The strongest storms will be
capable of large hail, damaging winds, and a few tornadoes. More
isolated, strong to severe storms are possible across parts of the
Northeast.
...Synopsis...
A vigorous, mid-level low over Ontario this evening is forecast to
evolve into an open wave while translating east into Quebec on
Tuesday. An accompanying belt of strong, mid/upper-level winds will
overspread the lower Great Lakes and northern New England in tandem
with modest height falls related to a vorticity maximum pivoting
through the base of the parent system. Elsewhere, a mid-level low
currently along the CA coast is expected to weaken while shifting
through the lower-CO Valley to the vicinity of the Four Corners
region. A belt of 50-70 kt winds at 500 mb are forecast downstream
from that feature, extending from the southern Plains into the Mid
South on Tuesday afternoon into evening.
In the low levels, a cold front is expected to extend from southeast
Quebec through the OH and mid-MS Valleys to low pressure over OK
Tuesday morning. The northern extension of the boundary will move
into the lower Great Lakes and northern New England during the peak
of the diurnal heating cycle. The segment of the front across the
Ozarks and Ozark Plateau may be temporarily displaced to the south
Tuesday morning due to overnight thunderstorm activity. However by
afternoon, the front is expected to refocus in the vicinity of the
MO-AR border, ahead of a weakening surface low moving through
eastern OK into western AR. The western extension of the cold front
trailing the surface low is expected to advance southeast through
the Red River Valley.
...Northeast Texas into the southern Missouri and western
Tennessee...
As mentioned in the synopsis, a complex of thunderstorms may be
ongoing at the start of the forecast period across portions of MO
into northern AR. That activity is expected to shift east of the
area by late morning or early afternoon, with some lingering shower
and thunderstorm development occurring to the north of the front in
central MO. In the wake of the early-day convection, HREF cloud
forecasts indicate the potential for considerable high-level clouds
and pockets of thicker low-cloudiness, which could limit the
potential for stronger diabatic warming within the pre-frontal air
mass. Nonetheless, the presence of boundary-layer dewpoints in the
60s in conjunction with an elevated-mixed layer (EML) plume will
support a moderately unstable air mass by afternoon with MLCAPE of
1000-2000 J/kg.
Neutral to slight height rises are forecast in the mid levels during
the peak of the diurnal heating cycle with model forecast soundings
indicating considerable capping at the base of the EML. As such,
eventual storm coverage remains uncertain. The 00z high-resolution
models suggest that isolated to widely scattered thunderstorms will
become increasingly likely by late afternoon or early evening along
the frontal segment along the MO-AR border, immediately
east/northeast of the surface low. Additional, isolated storm
development also appears possible from the vicinity of the surface
low southwest along the cold front into northeast TX, mainly during
the evening hours.
The favorable overlap of moderate instability and strong deep-layer
shear will favor supercell storm modes, especially given the
anticipated weak forcing for ascent. Large hail will be the
predominant severe-weather hazard initially. A few tornadoes appear
possible across portions of northern AR, potentially into western TN
from late afternoon through the evening association with any
sustained supercells. Here, the presence of a 35-40 kt low-level jet
will yield effective SRH of 200-300 m2/s2 amidst a moist/low-LCL
environment. Storms may eventually grow upscale into clusters, at
which point damaging winds would become a growing concern.
...Lower Great Lakes into northern New England...
Moisture advection occurring along a southwesterly low-level jet
will allow dewpoints to rise into the 50s within the pre-frontal
warm sector on Tuesday. And while mid-level lapse rates are not
expected to be particularly steep, the moisture increase combined
with daytime heating and the resultant steepening of low-level lapse
rates will result in MLCAPE of 500 to perhaps 1000 J/kg. Increasing
height falls aloft and convergence/lift along the cold front are
expected to support surface-based storm development by early
afternoon within the destabilizing air mass across portions of
upstate NY. The storms will quickly overspread northern portions of
VT, NH, and ME during the afternoon into early evening.
The 00z high-resolution models indicate the potential for transient
supercell and bowing structures, which appears reasonable given the
presence of a relatively strong, deep-layer wind field. In that
scenario, isolated occurrences of damaging winds and perhaps some
marginally severe hail appear possible. The tornado threat will be
conditional on sufficient instability to support more sustained
supercell structures. A level 1/Marginal Risk will be maintained;
however, if it becomes apparent that stronger instability will
develop than is currently anticipated, an upgraded to level 2/Slight
Risk may become necessary.
..Mead/Lyons.. 05/05/2026
Read more
MD 0640 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR SOUTH-CENTRAL ILLINOIS AND SOUTHERN INDIANA
Mesoscale Discussion 0640
NWS Storm Prediction Center Norman OK
0629 PM CDT Mon May 04 2026
Areas affected...South-central Illinois and Southern Indiana
Concerning...Severe potential...Watch possible
Valid 042329Z - 050200Z
Probability of Watch Issuance...40 percent
SUMMARY...An isolated severe threat for large hail is expected to
continue for a few hours across south-central Illinois, and may
affect southern Indiana. The for weather watch issuance is
uncertain.
DISCUSSION...A couple cells have recently develop to the northeast
of the St. Louis metro. The activity is located along the eastern
edge of a pocket of moderate instability, where the RAP has MLCAPE
around 1000 J/kg. The storms are being supported by an area of
low-level convergence and by large-scale ascent associated with a
subtle shortwave trough, evident on water vapor imagery. The WSR-88D
VWP near St Louis has effective shear in the 30 to 40 knot range,
and the RAP shows very steep mid-level lapse rates exceeding 7.5
C/km. This should be favorable for large hail with supercells that
form. However, a capping inversion is evident over much of
southeastern Illinois and southern Indiana. Also, RAP suggests that
instability is very weak in this same area. For this reason, the
storms are expected to remain elevated, and the eastern extent of
the severe threat is uncertain.
..Broyles/Hart.. 05/04/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LMK...IND...PAH...ILX...LSX...
LAT...LON 38058802 38218956 38489008 38859021 39299012 39638974
39798899 39748736 39618654 39338617 38828613 38318631
38088688 38058802
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
Read more
SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0752 PM CDT Mon May 04 2026
Valid 050100Z - 051200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN
KANSAS INTO NORTHERN INDIANA AND NORTHWEST OHIO...
...SUMMARY...
Widely scattered severe thunderstorms capable of large hail and
damaging wind gusts are possible from eastern Kansas into the
portions of the Ohio Valley this evening into tonight. A
conditional threat for severe storms with large to very large hail
extends into portions of southern Plains through the remainder of
the evening.
...Mid-Mississippi and Ohio Valleys....
Widely scattered, strong to severe storms are ongoing this evening
along and ahead of a progressive cold front from southern lower MI
into northern IL and far southeast IA with visible satellite
indicating additional storm attempts into portions of northern MO. A
separate area of thunderstorms is ongoing within the open warm
sector east of St. Louis where hail up two inches in diameter has
been reported. In the absence of more substantial boundary-layer
moisture content, 00z observed soundings revealed the presence of
steep low/mid-level lapse rates are largely contributing to MLCAPE
of around 1000 J/kg. Meanwhile, the accompanying kinematic
environment features a vertically veering wind profile with around
40 kt of effective bulk shear magnitudes and modestly strong
low-level shear (effective SRH of 150-200 m2/s2).
Current thinking is that ongoing storms will remain capable of
isolated occurrences of large hail and locally damaging wind gusts
for the next few hours as increasing moisture content along a
nocturnal low-level jet offsets cooling in the boundary layer. The
threat should tend to diminish overnight as the boundary layer
gradually stabilizes.
For additional information on near-term details, see MCDs 640 and
641.
...Eastern Kansas into western Missouri...
Isolated to widely scattered thunderstorms have persisted this
evening across portions of western into central KS, aided by a weak
mid-level impulse moving through the central High Plains. A number
of high-resolution models suggest that activity will intensify later
this evening into tonight as it drifts east of the I-35 corridor and
encounters an increasingly unstable air mass in place across eastern
KS into western MO. A strengthening low-level jet will enhance
moisture transport into the growing complex of storms with large
hail being the primary hazard initially. With time, the models
suggest upscale growth into one or more forward-propagating clusters
with an increased risk for damaging wind gusts.
..Mead.. 05/05/2026
Read more
SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0752 PM CDT Mon May 04 2026
Valid 050100Z - 051200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN
KANSAS INTO NORTHERN INDIANA AND NORTHWEST OHIO...
...SUMMARY...
Widely scattered severe thunderstorms capable of large hail and
damaging wind gusts are possible from eastern Kansas into the
portions of the Ohio Valley this evening into tonight. A
conditional threat for severe storms with large to very large hail
extends into portions of southern Plains through the remainder of
the evening.
...Mid-Mississippi and Ohio Valleys....
Widely scattered, strong to severe storms are ongoing this evening
along and ahead of a progressive cold front from southern lower MI
into northern IL and far southeast IA with visible satellite
indicating additional storm attempts into portions of northern MO. A
separate area of thunderstorms is ongoing within the open warm
sector east of St. Louis where hail up two inches in diameter has
been reported. In the absence of more substantial boundary-layer
moisture content, 00z observed soundings revealed the presence of
steep low/mid-level lapse rates are largely contributing to MLCAPE
of around 1000 J/kg. Meanwhile, the accompanying kinematic
environment features a vertically veering wind profile with around
40 kt of effective bulk shear magnitudes and modestly strong
low-level shear (effective SRH of 150-200 m2/s2).
Current thinking is that ongoing storms will remain capable of
isolated occurrences of large hail and locally damaging wind gusts
for the next few hours as increasing moisture content along a
nocturnal low-level jet offsets cooling in the boundary layer. The
threat should tend to diminish overnight as the boundary layer
gradually stabilizes.
For additional information on near-term details, see MCDs 640 and
641.
...Eastern Kansas into western Missouri...
Isolated to widely scattered thunderstorms have persisted this
evening across portions of western into central KS, aided by a weak
mid-level impulse moving through the central High Plains. A number
of high-resolution models suggest that activity will intensify later
this evening into tonight as it drifts east of the I-35 corridor and
encounters an increasingly unstable air mass in place across eastern
KS into western MO. A strengthening low-level jet will enhance
moisture transport into the growing complex of storms with large
hail being the primary hazard initially. With time, the models
suggest upscale growth into one or more forward-propagating clusters
with an increased risk for damaging wind gusts.
..Mead.. 05/05/2026
Read more
MD 0639 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF WESTERN AND CENTRAL OKLAHOMA AND INTO WESTERN NORTH TEXAS.
Mesoscale Discussion 0639
NWS Storm Prediction Center Norman OK
0450 PM CDT Mon May 04 2026
Areas affected...portions of western and central Oklahoma and into
western North Texas.
Concerning...Severe potential...Watch possible
Valid 042150Z - 042315Z
Probability of Watch Issuance...40 percent
SUMMARY...Isolated supercells are possible this afternoon and
evening with a risk for hail (some 2+ inch) and damaging winds. The
need for a watch is unclear, but will be closely monitored.
DISCUSSION...As of 2145 UTC, visible imagery showed high-based
cumulus towers deepening along the dryline across portions of
western OK and western North TX. Ample heating, despite some cirrus
has allowed temperatures to warm into the low to mid 90s F resulting
in moderate destabilization (MUCAPE 1000-1500 J/kg). Ascent from an
approaching shortwave trough and continued heating along the dryline
should remove remaining inhibition, allowing isolated storm
development over the next few hours across western OK and western
North TX.
Despite the somewhat limited buoyancy and marginal surface dewpoints
(mid-50s to near 60 F), veering and strengthening flow with height
beneath 100-kt westerly 200-mb flow will support supercells as the
primary storm mode. Isolated large to very large hail will be the
main risk with the stronger storms. Relatively high LCLs around 2000
m and the steep lapse rates in the low levels would also likely
support strong downdrafts capable of severe gusts with any
established storms.
The primary uncertainty remains the coverage and intensity of any
storms that develop. High LFC heights (3-4 km) and strong dry air
entrainment suggest storms will be slow to evolve and strengthen.
However, the environment is supportive of a conditional significant
hail risk given the supercell storm mode. Given this, isolated
storms are expected, suggesting a WW is unlikely. However, should
sufficient coverage of supercells develop, a WW could be needed.
Convective trends will be monitored closely into this evening.
..Lyons/Hart.. 05/04/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...TSA...FWD...OUN...SJT...LUB...
LAT...LON 35099934 36009878 36619786 36529624 36009576 35319571
34819588 34149635 33859689 33629733 33389841 33379938
33379978 33470009 33630031 33930029 34369996 35099934
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
Read more
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0430 PM CDT Mon May 04 2026
Valid 061200Z - 121200Z
...Synopsis...
An expansive positively-tilted upper trough will extend across the
Southwest to the Great Lakes region with an embedded shortwave over
the Rockies on Day 3/Wednesday. Concurrently, a broad upper-level
low over eastern Canada will encourage unsettled weather across the
Northeast with a cold front transporting plentiful moisture to
portions of the Mid-Atlantic and Southeast through Day 5/Friday.
Broader fire weather concerns may temporarily be dampened for much
of the eastern U.S. for the duration of the forecast period, given a
widespread transition to green up and expected appreciable
precipitation. An upper ridge will build across the Pacific
Northwest mid-week, resulting in above normal temperatures and dry
conditions to prevail for much of the western U.S. through the
weekend.
On Day 3/Wednesday, the upper trough will migrate atop the southern
Plains and West TX as an area of surface convergence develops east
of the Front Range. This feature is expected to send a cold front
through the TX Panhandle, while downslope westerly winds and a dry
airmass persists over West TX. Recent plentiful rainfall and
marginal fuels precludes the introduction of probabilities.
Beneath an upper ridge and northwesterly flow aloft, above normal
temperatures and a dry airmass will remain over much of the western
CONUS with sporadic areas of breezy conditions. Localized fire
weather concerns may emerge where terrain-induced winds and dry
fuels align. Farther east, persistent upper-level troughing over the
northern Plains and Upper Midwest will shunt most moisture chances
south of the area. Mostly dry and occasionally breezy conditions
will prevail, promoting localized fire weather concerns where fuels
remain dry and the green up transition has not yet occurred.
..Elizalde-Garcia.. 05/04/2026
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0430 PM CDT Mon May 04 2026
Valid 061200Z - 121200Z
...Synopsis...
An expansive positively-tilted upper trough will extend across the
Southwest to the Great Lakes region with an embedded shortwave over
the Rockies on Day 3/Wednesday. Concurrently, a broad upper-level
low over eastern Canada will encourage unsettled weather across the
Northeast with a cold front transporting plentiful moisture to
portions of the Mid-Atlantic and Southeast through Day 5/Friday.
Broader fire weather concerns may temporarily be dampened for much
of the eastern U.S. for the duration of the forecast period, given a
widespread transition to green up and expected appreciable
precipitation. An upper ridge will build across the Pacific
Northwest mid-week, resulting in above normal temperatures and dry
conditions to prevail for much of the western U.S. through the
weekend.
On Day 3/Wednesday, the upper trough will migrate atop the southern
Plains and West TX as an area of surface convergence develops east
of the Front Range. This feature is expected to send a cold front
through the TX Panhandle, while downslope westerly winds and a dry
airmass persists over West TX. Recent plentiful rainfall and
marginal fuels precludes the introduction of probabilities.
Beneath an upper ridge and northwesterly flow aloft, above normal
temperatures and a dry airmass will remain over much of the western
CONUS with sporadic areas of breezy conditions. Localized fire
weather concerns may emerge where terrain-induced winds and dry
fuels align. Farther east, persistent upper-level troughing over the
northern Plains and Upper Midwest will shunt most moisture chances
south of the area. Mostly dry and occasionally breezy conditions
will prevail, promoting localized fire weather concerns where fuels
remain dry and the green up transition has not yet occurred.
..Elizalde-Garcia.. 05/04/2026
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
MD 0638 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF THE MIDWEST AND SOUTHERN GREAT LAKES
Mesoscale Discussion 0638
NWS Storm Prediction Center Norman OK
0342 PM CDT Mon May 04 2026
Areas affected...portions of the Midwest and southern Great Lakes
Concerning...Severe potential...Watch possible
Valid 042042Z - 042245Z
Probability of Watch Issuance...40 percent
SUMMARY...Widely scattered to scattered thunderstorm development is
expected late this afternoon, with potential for severe/damaging
wind gusts and large hail. Watch issuance is possible for a portion
of the discussion area.
DISCUSSION...Prevailing southwesterly flow has yielded modest
moisture return across portions of the Midwest into the southern
Great Lakes region, with dewpoints climbing into the 40s/low-50s.
While a surface cold front remains displaced to the northwest,
expectation is for widely scattered to scattered strong to severe
thunderstorms to develop within the warm conveyor this afternoon as
convective temperatures are reached and remaining inhibition is
removed. A 700-mb speed max associated with an approaching shortwave
trough will help to promote 30-40 kts of effective bulk shear across
the region, with MLCAPE forecast in the 500-1250 J/kg range. This
will be sufficient to support storm organization into
multicells/clusters and perhaps transient supercell structures;
although, the lack stronger flow aloft and limited hodograph
elongation is likely to limit supercell intensity/persistence.
Dry mid-level air and well-mixed boundary layers (as sampled by
regional ACARS profiles and the 18z DVN observed sounding) will
support a risk for severe/damaging wind gusts. Large hail will also
be possible given modestly steep mid-level lapse rates (>7 C/km per
latest mesoanalysis). While a strengthening of 850 mb flow and some
accompanying increase in low-level hodograph curvature is expected
this evening (especially across northern Indiana and northwest Ohio
within the 21-00z time frame), the tornado threat remains uncertain
owing to the expectation for boundary layer moisture quality to
remain more limited across the region.
Thus, given the potential for these hazards, a Severe Thunderstorm
Watch is possible for a portion of the discussion area, particularly
from northeastern Illinois into northwestern Ohio where the
potential coverage of severe hazards appears greater.
..Chalmers/Smith.. 05/04/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...CLE...ILN...DTX...IWX...GRR...IND...LOT...ILX...
MKX...DVN...
LAT...LON 40518958 40679037 41009087 41529106 42019081 42459004
42658882 42808808 42928668 42858577 42578475 42178393
41858341 41368312 40998314 40728341 40518462 40438591
40448725 40458834 40478912 40518958
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
Read more
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0233 PM CDT Mon May 04 2026
Valid 042000Z - 051200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE MIDWEST INTO THE OHIO VALLEY...
...SUMMARY...
Scattered severe thunderstorms capable of large hail and damaging
wind gusts are possible across portions of the Midwest this
afternoon into tonight. A conditional threat for severe storms with
large to very large hail extends into portions of the
central/southern Plains.
...20Z Update...
The previous forecast remains largely on track. Only minor changes
were made to the thunder and severe probabilities to reflect the
latest trends in observations and high resolution model guidance.
..Squitieri.. 05/04/2026
.PREV DISCUSSION... /ISSUED 1130 AM CDT Mon May 04 2026/
...IL into the southern Great Lakes...
A mid-level vorticity maximum over the lower MO Valley is forecast
to move east across IL through the late afternoon and into IN-OH
tonight. An associated speed maximum at 700 mb will intensify and
overspread IL (40-50 kt) east into the southern Great Lakes while a
pronounced strengthening of 850-mb flow (50 kt) occurs during the
21-03z period. Cold mid-level temperatures (-18 deg C at 500 mb)
will act to offset initially meager moisture. Model guidance varies
considerably regarding moisture quality with ample spread amongst
different model cores/PBL schemes. However, it seems a narrow
corridor of lower to mid 50s surface dewpoints will extend
east-northeast from the lower MO Valley into the southern Great
Lakes by mid to late afternoon. Forecast soundings show weak to
moderate buoyancy (500-1250 J/kg MLCAPE). Morning model guidance
shows widely scattered to scattered storms developing within the
warm conveyor during peak heating as convective inhibition erodes.
Have expanded the Slight Risk farther east into this region to
account for a hail/wind risk with the stronger storms. Uncertainty
remains regarding quality of boundary-layer moisture across the
northern third of IN into northwest OH where hodographs become
enlarged later this afternoon into the early evening. Will
re-evaluate the tornado risk for the 20 UTC outlook if in fact
moisture quality seems sufficient for a focused, short-duration
tornado risk across the aforementioned corridor.
...Eastern KS into the Mid MS Valley...
Thunderstorm development is anticipated during the afternoon along a
cold forecast to extend through southern WI and
eastern/southern IA. Thunderstorms along the front will initially be
displaced north of the better shear and buoyancy, so somewhat
transient updraft structures and/or frontal undercutting will likely
limit storm severity. Even so, high cloud bases and a deeply mixed
boundary layer could result in a few strong gusts. Later in the
evening, more storm development appears likely on the front as it
moves into eastern KS and northern/central MO. Here, stronger shear
and buoyancy should support more robust updrafts and a relatively
higher probability for severe storms. Large to very large hail is
the primary risk.
...Central Kansas into Oklahoma and northern Texas...
A dryline will extend from central KS south-southwestward into
northwest TX by mid afternoon as a surface low evolves near the TX
Panhandle/OK/KS border region. Strong diurnal heating will likely
erode most convective inhibition by the early evening, while steep
lapse rates contribute to moderate buoyancy along the dryline.
Isolated thunderstorms are possible on the dryline from central KS
into northwest TX during the 22-02 UTC period. Veering and
strengthening flow with height beneath 100-kt westerly 200-mb flow
will support supercells. Isolated large to very large hail will be
the primary risk with the stronger storms, although severe gusts are
also possible.
Read more
