SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1137 PM CST Wed Dec 17 2025
Valid 191200Z - 201200Z
...Synopsis...
Shortwave ridging aloft will break down through the day Friday and
another strong mid-level jet will move across the Rockies. In the
Plains, a broad and moderately deep surface trough will develop and
shift eastward. These features will combine to promote another
strong downslope wind regime in the immediate lee of the Rockies.
...Central/southern High Plains...
Strong downslope winds will occur in the I-25 corridor again on
Friday. Sustained winds of 20-30 mph, especially in Wyoming and
Colorado, are expected. Wind gusts of greater than 60 mph could
occur in the typically wind-prone gaps/foothills. Winds in New
Mexico will generally be 15-20 mph. As with the last downslope wind
event, RH will be uncertain during the afternoon. Higher confidence
in 15-20% exists in New Mexico. With northward extent, RH will
generally be higher, though pockets of 15-20% are at least possible.
Cloud cover near the terrain is partly driving this uncertainty.
Given the strength of winds and continued drying of fuels, elevated
to locally critical conditions are expected.
...Southern Plains...
Winds of 15-20 mph will develop by the afternoon as the surface
trough deepens. Dry return flow should foster 15-25% RH. Enhanced
winds within the lowest 2-3 km should also foster stronger wind
gusts, particularly during the afternoon/peak heating.
..Wendt.. 12/18/2025
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1137 PM CST Wed Dec 17 2025
Valid 191200Z - 201200Z
...Synopsis...
Shortwave ridging aloft will break down through the day Friday and
another strong mid-level jet will move across the Rockies. In the
Plains, a broad and moderately deep surface trough will develop and
shift eastward. These features will combine to promote another
strong downslope wind regime in the immediate lee of the Rockies.
...Central/southern High Plains...
Strong downslope winds will occur in the I-25 corridor again on
Friday. Sustained winds of 20-30 mph, especially in Wyoming and
Colorado, are expected. Wind gusts of greater than 60 mph could
occur in the typically wind-prone gaps/foothills. Winds in New
Mexico will generally be 15-20 mph. As with the last downslope wind
event, RH will be uncertain during the afternoon. Higher confidence
in 15-20% exists in New Mexico. With northward extent, RH will
generally be higher, though pockets of 15-20% are at least possible.
Cloud cover near the terrain is partly driving this uncertainty.
Given the strength of winds and continued drying of fuels, elevated
to locally critical conditions are expected.
...Southern Plains...
Winds of 15-20 mph will develop by the afternoon as the surface
trough deepens. Dry return flow should foster 15-25% RH. Enhanced
winds within the lowest 2-3 km should also foster stronger wind
gusts, particularly during the afternoon/peak heating.
..Wendt.. 12/18/2025
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1137 PM CST Wed Dec 17 2025
Valid 191200Z - 201200Z
...Synopsis...
Shortwave ridging aloft will break down through the day Friday and
another strong mid-level jet will move across the Rockies. In the
Plains, a broad and moderately deep surface trough will develop and
shift eastward. These features will combine to promote another
strong downslope wind regime in the immediate lee of the Rockies.
...Central/southern High Plains...
Strong downslope winds will occur in the I-25 corridor again on
Friday. Sustained winds of 20-30 mph, especially in Wyoming and
Colorado, are expected. Wind gusts of greater than 60 mph could
occur in the typically wind-prone gaps/foothills. Winds in New
Mexico will generally be 15-20 mph. As with the last downslope wind
event, RH will be uncertain during the afternoon. Higher confidence
in 15-20% exists in New Mexico. With northward extent, RH will
generally be higher, though pockets of 15-20% are at least possible.
Cloud cover near the terrain is partly driving this uncertainty.
Given the strength of winds and continued drying of fuels, elevated
to locally critical conditions are expected.
...Southern Plains...
Winds of 15-20 mph will develop by the afternoon as the surface
trough deepens. Dry return flow should foster 15-25% RH. Enhanced
winds within the lowest 2-3 km should also foster stronger wind
gusts, particularly during the afternoon/peak heating.
..Wendt.. 12/18/2025
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1135 PM CST Wed Dec 17 2025
Valid 181200Z - 191200Z
...CRITICAL FIRE WEATHER AREA FOR CENTRAL KANSAS INTO FAR NORTHERN
OKLAHOMA...
...Synopsis...
A cold front will push through the Plains into the Mississippi/Ohio
Valleys today. On the western flank of the upper-trough, behind the
cold front, strong northwesterly winds will persist through the
morning and into the early/mid afternoon within the central/southern
Plains. The cold air will lag behind the actual front.
...Central/southern Plains...
Winds of 20-30 mph (with higher gusts) are probable across Kansas
into northern Oklahoma. The strongest winds will occur in Kansas
where surface temperatures will remain cooler. Despite the cold
advection, clear skies and dry air will support RH in the 15-25%
range in Texas/Oklahoma. RH in Kansas will likely be above 25% in
most areas. However, the strong winds and drying fine fuels will
still support rapid fire spread in these marginally critical RH
conditions. Critical conditions are expected where the greatest
overlap of strong surface winds and at least marginally low RH.
Near-critical conditions are possible in parts of Oklahoma and
Texas, but marginal fuels and less intense surface winds preclude
expansion of highlights into these areas.
..Wendt.. 12/18/2025
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1135 PM CST Wed Dec 17 2025
Valid 181200Z - 191200Z
...CRITICAL FIRE WEATHER AREA FOR CENTRAL KANSAS INTO FAR NORTHERN
OKLAHOMA...
...Synopsis...
A cold front will push through the Plains into the Mississippi/Ohio
Valleys today. On the western flank of the upper-trough, behind the
cold front, strong northwesterly winds will persist through the
morning and into the early/mid afternoon within the central/southern
Plains. The cold air will lag behind the actual front.
...Central/southern Plains...
Winds of 20-30 mph (with higher gusts) are probable across Kansas
into northern Oklahoma. The strongest winds will occur in Kansas
where surface temperatures will remain cooler. Despite the cold
advection, clear skies and dry air will support RH in the 15-25%
range in Texas/Oklahoma. RH in Kansas will likely be above 25% in
most areas. However, the strong winds and drying fine fuels will
still support rapid fire spread in these marginally critical RH
conditions. Critical conditions are expected where the greatest
overlap of strong surface winds and at least marginally low RH.
Near-critical conditions are possible in parts of Oklahoma and
Texas, but marginal fuels and less intense surface winds preclude
expansion of highlights into these areas.
..Wendt.. 12/18/2025
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1135 PM CST Wed Dec 17 2025
Valid 181200Z - 191200Z
...CRITICAL FIRE WEATHER AREA FOR CENTRAL KANSAS INTO FAR NORTHERN
OKLAHOMA...
...Synopsis...
A cold front will push through the Plains into the Mississippi/Ohio
Valleys today. On the western flank of the upper-trough, behind the
cold front, strong northwesterly winds will persist through the
morning and into the early/mid afternoon within the central/southern
Plains. The cold air will lag behind the actual front.
...Central/southern Plains...
Winds of 20-30 mph (with higher gusts) are probable across Kansas
into northern Oklahoma. The strongest winds will occur in Kansas
where surface temperatures will remain cooler. Despite the cold
advection, clear skies and dry air will support RH in the 15-25%
range in Texas/Oklahoma. RH in Kansas will likely be above 25% in
most areas. However, the strong winds and drying fine fuels will
still support rapid fire spread in these marginally critical RH
conditions. Critical conditions are expected where the greatest
overlap of strong surface winds and at least marginally low RH.
Near-critical conditions are possible in parts of Oklahoma and
Texas, but marginal fuels and less intense surface winds preclude
expansion of highlights into these areas.
..Wendt.. 12/18/2025
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0621 PM CST Wed Dec 17 2025
Valid 180100Z - 181200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Isolated thunderstorms are possible along portions of the TX/LA Gulf
coasts tonight.
...01z Update...
Weak, southern-stream short-wave trough is advancing off the south
TX coast early this evening. A few thunderstorms linger near the
center of a weak midlevel circulation around the Corpus Christi
region; however, the most concentrated deep convection is now
focused offshore and should continue to be shunted east ahead of the
short wave.
Isolated thunderstorms may eventually develop ahead of this feature
downstream across southeast LA later tonight, but negligible
buoyancy currently exists on the 00z sounding from LIX. By the end
of the period, adequate destabilization should materialize across
this region such that lightning is possible with deep convection,
primarily after 08-09z.
..Darrow.. 12/18/2025
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SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0621 PM CST Wed Dec 17 2025
Valid 180100Z - 181200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Isolated thunderstorms are possible along portions of the TX/LA Gulf
coasts tonight.
...01z Update...
Weak, southern-stream short-wave trough is advancing off the south
TX coast early this evening. A few thunderstorms linger near the
center of a weak midlevel circulation around the Corpus Christi
region; however, the most concentrated deep convection is now
focused offshore and should continue to be shunted east ahead of the
short wave.
Isolated thunderstorms may eventually develop ahead of this feature
downstream across southeast LA later tonight, but negligible
buoyancy currently exists on the 00z sounding from LIX. By the end
of the period, adequate destabilization should materialize across
this region such that lightning is possible with deep convection,
primarily after 08-09z.
..Darrow.. 12/18/2025
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SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0348 PM CST Wed Dec 17 2025
Valid 191200Z - 251200Z
Fire weather concerns are expected to persist through the remainder
of the work week and into the weekend across the southern Plains and
central/southern High Plains. A largely zonal upper-level flow
regime is expected to persist through early next week before broad
scale ridging becomes established over the south-central CONUS. This
synoptic regime will favor lee troughing followed by frontal
passages across the Plains with rain/snow chances for most regions,
except for the Southwest/southern Plains where dry conditions will
persist for the next several days. Long-range ensembles do show the
potential for widespread precipitation late in the forecast period
(D6/Mon to D8/Wed) for parts of the Southwest, but steady fuel
drying is anticipated for the southern Plains/High Plains through
next week.
...D3/Friday - High Plains/southern Plains...
Dry conditions will prevail across the southern Plains early
D3/Friday in the wake of Thursday's frontal passage. A surface high
shifting eastward into the lower MS Valley will promote
southwesterly winds across much of TX, OK, and KS. Coincidentally,
an upper-disturbance moving across the northern Rockies will promote
lee troughing along the High Plains, which will induce another
downslope flow regime along the central Rockies and augment the
pressure gradient over the Plains. 15-25 mph winds are anticipated
within the dry return flow regime with RH reductions into the 15-25%
range probable from the Permian Basin into western OK. In the lee of
the Rockies, confidence in RH reductions is limited, but a strong
wind signal coupled with drying fine fuels should promote at least a
wind-driven fire weather concern.
...D4/Saturday - southern High Plains...
A cold front associated with a northern Plains/Great Lakes surface
low will gradually push into the southern Plains through the day
Saturday. While confidence in how far south this front will progress
by peak heating remains uncertain, the general consensus among
guidance is that 15-20 mph westerly pre-frontal winds will support
adequate downslope warming/drying for areas of elevated to critical
fire weather conditions.
..Moore.. 12/17/2025
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1125 AM CST Wed Dec 17 2025
Valid 181200Z - 191200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Severe potential will be limited on Thursday, but isolated strong
wind gusts are possible across portions of the Lower Ohio and
Tennessee Valleys.
...Synopsis...
A strong upper trough will move across Midwest on Thursday with low
pressure moving across the Great Lakes. A cold front will extend
south from this low with wind shift moving across the OH and TN
Valleys during the day and into the evening. Minimal destabilization
is forecast ahead of the front as clouds and early day precipitation
hamper heating. Mostly elevated instability is forecast, though
shear profiles will be strong. Despite a marginal/cool boundary
layer across the warm sector, deeper ascent along the cold front
could support shallow moist convection capable of augmenting gusts
with the frontal passage.
Elsewhere, moisture and instability will increase overnight well off
the NC Coast, but supercells developing over the water may
eventually skirt the Outer Banks of NC toward the end of the period.
At this time it appears the instability gradient will remain
offshore.
..Jewell.. 12/17/2025
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1058 AM CST Wed Dec 17 2025
Valid 171700Z - 181200Z
The previous forecast remains on track with only minor expansions
made across southeast CO/southwest KS to reflect latest high-res
guidance. 16 UTC surface observations show winds beginning to
increase along the northern CO Front Range, but the strongest winds
are expected later this afternoon (mainly between 20-00 UTC) as the
mid-level jet begins to impinge on the northern Rockies. It remains
unclear exactly how severe RH reductions will be in the lee of the
immediate front range where peak winds are expected. While some
guidance shows RH minimums near 20%, morning solutions don't appear
to be accurately capturing recent satellite trends with more
widespread cloud cover noted in GOES imagery than depicted in recent
HRRR/RRFS runs. This continues to limit confidence in the potential
for widespread critical fire weather conditions, though localized
critical conditions may emerge if sufficient clearing can occur.
Regardless, the strong winds coupled with slowly increasing ERC
values (near the 70th percentile) should still support a wind-driven
fire weather risk. See the previous discussion below for additional
details.
..Moore.. 12/17/2025
.PREV DISCUSSION... /ISSUED 1150 PM CST Tue Dec 16 2025/
...Synopsis...
A potent upper trough will move through the Northwest and reach the
Plains by Thursday morning. At the surface, a cyclone will deepen in
the northern Plains with a trough extending into the
central/southern Plains.
...Central/southern High Plains...
Strong mid-level winds will be nearly perpendicular to the Rockies.
This, coupled with a strong cross-Divide pressure gradient, will
foster strong sustained winds and stronger gusts in the immediate
lee of the terrain. Sustained 20-30 mph winds will be probable in
the terrain-favored areas. A period of wind gusts to 60-70 mph are
expected in the lower foothills. Farther east and south, 15-20 mph
will become more common. RH will be above elevated criteria in many
places, but 15-25% will be possible from Wyoming into Colorado.
Farther south, RH will more likely be around 15-20%. With fuels
having continued to dry, the strong surface winds will still lead to
elevated to locally critical fire weather.
...Piedmont...
Dry and modestly breezy conditions appear possible within the region
during the afternoon. RH could fall as low as 20-25%, but there is
variability within guidance. Winds will generally be light at around
10 mph. Locally elevated conditions are possible, but the
duration/spatial extent is too limited and uncertain for highlights.
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1022 AM CST Wed Dec 17 2025
Valid 171630Z - 181200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTHERN IDAHO AND NORTHERN UTAH...
...SUMMARY...
While strong to locally severe winds may occur with low-topped
convection through early afternoon across parts of southern Idaho
and northern Utah, the overall threat for organized severe
thunderstorms appears low.
...Interior Northwest and Northern Great Basin/Rockies...
A powerful mid-level shortwave trough and associated sub-980 mb
surface low will move quickly eastward today across the interior
Northwest/northern Rockies and adjacent western Canada. A strong
surface cold front will likewise translate east-southeastward over
the northern Intermountain/Great Basin region late this morning into
the afternoon. Widespread cloud cover remains prevalent ahead of the
front across southern ID into northern UT and vicinity, with cool
surface temperatures and very limited low-level moisture also
present. MUCAPE is expected to remain only barely sufficient to
support convection. But, given the enhanced flow at low levels noted
on recent VWPs from KCBX/KSFX, it is not entirely out of the
question that convectively augmented gusts may exceed the already
strong background gradient winds on a localized basis. The Marginal
Risk has therefore been maintained for parts of southern ID/northern
UT and vicinity, even though the overall threat for organized severe
thunderstorms will remain low.
..Gleason/Weinman.. 12/17/2025
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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0655 AM CST Wed Dec 17 2025
Valid 171300Z - 181200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHWEST AND NORTHERN INTERMOUNTAIN REGION...
...SUMMARY...
Sporadic severe wind gusts may accompany low-topped convection
across parts of the Northwest and northern Intermountain region this
morning into midday.
...Northwest/Northern Intermountain region...
A progressive/vigorous shortwave trough will continue to modestly
amplify and otherwise race east-southeastward from the
Washington/British Columbia border vicinity this morning to the
northern Plains tonight. Intense deep-tropospheric flow (highlighted
by 55-85 kt at 700 mb) will accompany this wave, yielding widespread
high winds across much of the Northwest to the northern Great
Plains.
Low-topped convection, occasionally capable of lightning and
semi-organized line segments, will continue in association with the
east/southeastward-advancing cold front, with convection potentially
expanding by late morning towards the Snake River Plain/Yellowstone
vicinity and potentially other parts of the northeast Great Basin by
afternoon. Surface-based instability will be very limited, but some
convectively enhanced wind gusts may occur.
..Guyer/Lyons.. 12/17/2025
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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0655 AM CST Wed Dec 17 2025
Valid 171300Z - 181200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHWEST AND NORTHERN INTERMOUNTAIN REGION...
...SUMMARY...
Sporadic severe wind gusts may accompany low-topped convection
across parts of the Northwest and northern Intermountain region this
morning into midday.
...Northwest/Northern Intermountain region...
A progressive/vigorous shortwave trough will continue to modestly
amplify and otherwise race east-southeastward from the
Washington/British Columbia border vicinity this morning to the
northern Plains tonight. Intense deep-tropospheric flow (highlighted
by 55-85 kt at 700 mb) will accompany this wave, yielding widespread
high winds across much of the Northwest to the northern Great
Plains.
Low-topped convection, occasionally capable of lightning and
semi-organized line segments, will continue in association with the
east/southeastward-advancing cold front, with convection potentially
expanding by late morning towards the Snake River Plain/Yellowstone
vicinity and potentially other parts of the northeast Great Basin by
afternoon. Surface-based instability will be very limited, but some
convectively enhanced wind gusts may occur.
..Guyer/Lyons.. 12/17/2025
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Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0357 AM CST Wed Dec 17 2025
Valid 201200Z - 251200Z
...DISCUSSION...
Southerly low-level flow will return to the southern Plains on
D4/Saturday. This will bring 60sF dewpoints to east Texas and much
of Louisiana with weak destabilization anticipated. A few storms may
be possible across Louisiana on Saturday night, but shear will be
weak. Minimal vertical shear combined with limited forcing and only
weak instability will preclude any severe weather threat.
Isolated thunderstorm activity is possible from D5/Sunday through
the first half of next week from East Texas and Louisiana into the
Ozarks and into the Midwest as slight enhancements of the low-level
jet promote isentropic ascent. Through this period, low to mid 60s
dewpoints will progressively advance farther inland. However,
instability should remain weak as mid-level heights build and
mid-level temperatures warm. Therefore, despite the inland moisture
early next week, severe weather potential remains low due to weak
instability, weak forcing, and building heights aloft.
Read more
Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0357 AM CST Wed Dec 17 2025
Valid 201200Z - 251200Z
...DISCUSSION...
Southerly low-level flow will return to the southern Plains on
D4/Saturday. This will bring 60sF dewpoints to east Texas and much
of Louisiana with weak destabilization anticipated. A few storms may
be possible across Louisiana on Saturday night, but shear will be
weak. Minimal vertical shear combined with limited forcing and only
weak instability will preclude any severe weather threat.
Isolated thunderstorm activity is possible from D5/Sunday through
the first half of next week from East Texas and Louisiana into the
Ozarks and into the Midwest as slight enhancements of the low-level
jet promote isentropic ascent. Through this period, low to mid 60s
dewpoints will progressively advance farther inland. However,
instability should remain weak as mid-level heights build and
mid-level temperatures warm. Therefore, despite the inland moisture
early next week, severe weather potential remains low due to weak
instability, weak forcing, and building heights aloft.
Read more
SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0221 AM CST Wed Dec 17 2025
Valid 191200Z - 201200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Thunderstorms are expected along the East Coast Friday morning and
in the Pacific Northwest Friday afternoon through Friday night.
...Discussion...
A strong cold front will be moving quickly eastward Friday morning
with a shallow convective band along the front. A few stronger
storms are possible as the front interacts with slightly greater
moisture/instability near the coast. However, it is unclear whether
storms will intensify before they move offshore. The best potential
for a few stronger cells with some gusty winds will be across
southeast Virginia and eastern North Carolina.
In the wake of this cold front, cool/dry conditions associated with
a surface high will bring dry conditions to much of the eastern
CONUS. A few isolated thunderstorms will be possible in the Pacific
Northwest as temperatures cool aloft.
..Bentley.. 12/17/2025
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SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1251 AM CST Wed Dec 17 2025
Valid 181200Z - 191200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS CENTERED OVER
KENTUCKY AND TENNESSEE...
...SUMMARY...
Isolated damaging wind gusts are possible across portions of the
Lower Ohio and Tennessee Valleys on Thursday.
...Synopsis...
A strong mid-level jet streak will round the base of the mid-level
trough across the central Plains early Thursday and emerge across
the Ohio Valley by Thursday afternoon/evening. This trough will
continue east and take on a more neutral to perhaps negative tilt by
early Friday across the East Coast. A strong (sub 990mb) surface low
will move from the Upper Midwest to southern Quebec with a trailing
cold front sweeping from the Midwest to the East Coast.
...OH/TN Valleys...
The cold front is expected to interact with the richer low-level
moisture early in the period across Illinois and Missouri with a
shallow line of thunderstorms expected to develop. In addition, some
weak elevated instability may develop ahead of this front as cooling
mid-level temperatures result in sufficient elevated instability for
storms. Low-level instability ahead of the front is expected to
remain quite weak (100 to 200 J/kg). A strong frontal circulation
should overcome the weak instability and produce sufficient lift for
lightning. Any updrafts deep enough to produce lightning, and with
minimal inhibition (seemingly around 55F surface dewpoint) may also
have at least some isolated damaging wind threat given the 60 to 70
knot low-level jet around 1km.
Greater instability is expected south of the TN/MS/AL border where
upper 50s to low 60s dewpoints are forecast. However, despite the
more favorable thermodynamics, the upper-level forcing will be
weaker. Therefore, it is unclear whether the line of storms will
continue that far south, and additional convection ahead of the
front will likely struggle given the weak lapse rates/minimal
heating.
...Eastern Virginia into North Carolina...
Strong storms and potential supercells are expected over the warm
Gulf Stream waters Thursday evening. Some guidance indicates surface
based instability may advect inland across far eastern North
Carolina which would allow some of these stronger storms to move
inland. Current expectation is for stronger storms and 60+F
dewpoints to remain mostly offshore, so no marginal risk will be
added.
Late in the period, as the cold front crosses the Appalachians,
some increase in storm strength is anticipated as mid 50s dewpoints
east of the Appalachians provide weak instability to fuel the
storms. If more aggressive inland moisture advection occurs, similar
to the scenario mentioned above, some marginal damaging wind threat
could materialize given the strong wind field.
..Bentley.. 12/17/2025
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