WW 0425 Status Updates
STATUS REPORT ON WW 425
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 ESE CVS
TO 40 NW CDS TO 20 SSE HLC TO 15 SSW MCK.
REMAINING VALID PORTION OF WW MAY BE ALLOWED TO EXPIRE AT 01/03Z.
..KERR..07/01/26
ATTN...WFO...PUB...GLD...DDC...AMA...LUB...
STATUS REPORT FOR WS 425
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
KSC039-051-065-135-137-179-195-010300-
KS
. KANSAS COUNTIES INCLUDED ARE
DECATUR ELLIS GRAHAM
NESS NORTON SHERIDAN
TREGO
TXC011-017-045-069-079-129-153-189-219-279-303-369-437-010300-
TX
. TEXAS COUNTIES INCLUDED ARE
ARMSTRONG BAILEY BRISCOE
CASTRO COCHRAN DONLEY
FLOYD HALE HOCKLEY
LAMB LUBBOCK PARMER
SWISHER
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
Read more
MD 1404 CONCERNING SEVERE THUNDERSTORM WATCH 425... FOR PARTS OF WESTERN KANSAS
Mesoscale Discussion 1404
NWS Storm Prediction Center Norman OK
0545 PM CDT Tue Jun 30 2026
Areas affected...parts of western Kansas
Concerning...Severe Thunderstorm Watch 425...
Valid 302245Z - 010045Z
The severe weather threat for Severe Thunderstorm Watch 425
continues.
SUMMARY...Substantive further intensification of an organizing
cluster of storms appears possible into early evening, accompanied
by a continuing risk for severe hail, and increasing potential to
produce swaths of strong to severe wind gusts.
DISCUSSION...Based on mesoanalysis output, strongest continuing
destabilization the past few hours has been focused across western
Kansas, due to further boundary-layer heating and moisture
advection. This is focused within deepening surface troughing,
where veering from modest near-surface southeasterlies beneath 30-40
kt southwesterlies around 500 mb are contributing to sufficient
shear for organized convective development. Rapid Refresh suggests
at least some further strengthening of flow/shear are possible into
early evening, in the presence of moderate to large potential
instability.
Aided by forcing for ascent associated with lower/mid-tropospheric
warm advection north of the Raton Ridge vicinity of southeastern
Colorado, an organizing cluster of storms, including one evolving
meso-beta scale cyclonic circulation has evolved. Although
mid-levels remain warm, and the onset of boundary-layer cooling will
result in increasing inhibition for boundary-layer parcels, the
environment appears conducive to considerable further
intensification of the ongoing cluster as it propagates
north-northeastward into early evening.
..Kerr.. 06/30/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GID...DDC...GLD...AMA...PUB...
LAT...LON 38670195 39730129 39659888 38269977 37000097 36850164
37110206 38670195
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
Read more
MD 1405 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF THE MICHIGAN UPPER PENINSULA
Mesoscale Discussion 1405
NWS Storm Prediction Center Norman OK
0635 PM CDT Tue Jun 30 2026
Areas affected...portions of the Michigan Upper Peninsula
Concerning...Severe potential...Watch possible
Valid 302335Z - 010100Z
Probability of Watch Issuance...40 percent
SUMMARY...An isolated supercell that has recently developed across
the central portions of the Michigan Upper Peninsula will pose a
risk for all severe hazards.
DISCUSSION...An isolated, splitting supercell has recently developed
in Delta County, Michigan. While the left split will quickly move
into a less favorable air mass overlying Lake Superior, a narrow
corridor of severe potential will likely exist with the right split
across downstream portions of the Michigan Upper Peninsula. Large
hail and damaging wind gusts will be possible with this storm over
the next 1-2 hours, along with the potential for an isolated tornado
given enhanced 0-500 m SRH (approximately 100 m2/s2 per latest
objective analysis). Cooler temperatures and increased capping
farther east should tend to limit the longevity of this threat.
..Chalmers/Thompson.. 06/30/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...APX...MQT...
LAT...LON 46408696 46538675 46568632 46488573 46308557 46098559
45898576 45828632 45928694 46128709 46278707 46408696
MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
Read more
MD 1406 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PARTS OF NORTHEASTERN COLORADO...SOUTHEASTERN WYOMING...SOUTHWESTERN NEBRASKA
Mesoscale Discussion 1406
NWS Storm Prediction Center Norman OK
0714 PM CDT Tue Jun 30 2026
Areas affected...Parts of northeastern Colorado...southeastern
Wyoming...southwestern Nebraska
Concerning...Severe potential...Watch possible
Valid 010014Z - 010215Z
Probability of Watch Issuance...60 percent
SUMMARY...Intensifying thunderstorm development, including evolving
supercells posing a risk for large hail, locally damaging wind
gusts, and perhaps a tornado, through 8-10 PM MDT.
DISCUSSION...Low-level convergence has become focused north of the
Palmer Divide to the northeast of Denver, with a focused area of
lower/mid-tropospheric warm advection developing northward into the
Cheyenne Ridge. The stronger warm advection is forecast to slowly
shift across and east-northeast of the Cheyenne Ridge through
02-04Z, downstream of a notable short wave trough progressing
northeast of the Wasatch.
Large-scale ascent has been supporting increasing convective
development off the Front Range to the northeast of Denver, as
boundary layer moisture return on east-southeasterly near-surface
flow gradually contributes to destabilization across the adjacent
plains. Though inhibition beneath warm mid-levels will begin to
result in increasing inhibition for boundary-layer parcels, further
moistening will contribute to increasingly sizable potential
instability.
Within the stronger large-scale ascent, the environment is likely to
become conducive to intensifying thunderstorm development, in the
presence of strong shear. This may include supercells initially,
then an organizing and upscale growing cluster later this evening
and overnight.
..Kerr/Thompson.. 07/01/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LBF...GLD...BOU...CYS...
LAT...LON 41260356 41850093 40440193 39830310 41260356
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
Read more
WW 0423 Status Updates
STATUS REPORT ON WW 423
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 ESE ROC
TO 35 S UCA TO 35 NE MSV.
..CHALMERS..06/30/26
ATTN...WFO...ALY...BGM...BUF...BTV...
STATUS REPORT FOR WS 423
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
NYC007-017-023-025-107-109-010040-
NY
. NEW YORK COUNTIES INCLUDED ARE
BROOME CHENANGO CORTLAND
DELAWARE TIOGA TOMPKINS
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
Read more
WW 0424 Status Updates
STATUS REPORT ON WW 424
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 S MSP TO
25 WNW AUW TO 15 WNW RHI.
..CHALMERS..06/30/26
ATTN...WFO...ARX...MPX...GRB...
STATUS REPORT FOR WS 424
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MNC039-109-157-169-010040-
MN
. MINNESOTA COUNTIES INCLUDED ARE
DODGE OLMSTED WABASHA
WINONA
WIC009-019-029-053-061-067-069-073-075-078-083-087-091-097-115-
121-135-141-010040-
WI
. WISCONSIN COUNTIES INCLUDED ARE
BROWN CLARK DOOR
JACKSON KEWAUNEE LANGLADE
LINCOLN MARATHON MARINETTE
MENOMINEE OCONTO OUTAGAMIE
PEPIN PORTAGE SHAWANO
TREMPEALEAU WAUPACA WOOD
LMZ521-522-542-010040-
Read more
WW 424 SEVERE TSTM MN WI LM 302020Z - 010300Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 424
NWS Storm Prediction Center Norman OK
320 PM CDT Tue Jun 30 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Southeast Minnesota
Wisconsin
Lake Michigan
* Effective this Tuesday afternoon and evening from 320 PM until
1000 PM CDT.
* Primary threats include...
Scattered large hail and isolated very large hail events to 2
inches in diameter possible
Scattered damaging wind gusts to 70 mph possible
A tornado or two possible
SUMMARY...Scattered strong to severe thunderstorms are expected to
intensify, generally near where storms moved through the region
earlier day. This renewed development may produce large hail and
damaging winds into this evening within a very moist and unstable
environment.
The severe thunderstorm watch area is approximately along and 45
statute miles north and south of a line from 40 miles north
northwest of Rochester MN to 45 miles northeast of Green Bay WI. For
a complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU4).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 423...
AVIATION...A few severe thunderstorms with hail surface and aloft to
2 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 600. Mean storm motion vector
24025.
...Guyer
Read more
WW 0425 Status Updates
STATUS REPORT ON WW 425
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..KERR..06/30/26
ATTN...WFO...PUB...GLD...DDC...AMA...LUB...
STATUS REPORT FOR WS 425
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
COC009-099-010040-
CO
. COLORADO COUNTIES INCLUDED ARE
BACA PROWERS
KSC023-039-051-055-057-063-065-067-069-071-075-081-083-093-101-
109-119-129-135-137-153-171-175-179-181-187-189-193-195-199-203-
010040-
KS
. KANSAS COUNTIES INCLUDED ARE
CHEYENNE DECATUR ELLIS
FINNEY FORD GOVE
GRAHAM GRANT GRAY
GREELEY HAMILTON HASKELL
HODGEMAN KEARNY LANE
LOGAN MEADE MORTON
NESS NORTON RAWLINS
SCOTT SEWARD SHERIDAN
SHERMAN STANTON STEVENS
THOMAS TREGO WALLACE
WICHITA
Read more
WW 425 SEVERE TSTM CO KS OK TX 302055Z - 010300Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 425
NWS Storm Prediction Center Norman OK
355 PM CDT Tue Jun 30 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Southeast Colorado
Western Kansas
Oklahoma Panhandle
Texas Panhandle and South Plains
* Effective this Tuesday afternoon and evening from 355 PM until
1000 PM CDT.
* Primary threats include...
Scattered damaging winds likely with isolated significant gusts
to 85 mph possible
Scattered large hail and isolated very large hail events to 2.5
inches in diameter possible
SUMMARY...Widely scattered severe thunderstorms are expected to
increase through early evening regionally, with these storms capable
of large hail and severe-caliber wind gusts. An organized cluster of
storms may evolve this evening particularly across western Kansas.
The severe thunderstorm watch area is approximately along and 60
statute miles east and west of a line from 60 miles northwest of
Hill City KS to 25 miles southwest of Plainview TX. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU5).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 423...WW 424...
AVIATION...A few severe thunderstorms with hail surface and aloft to
2.5 inches. Extreme turbulence and surface wind gusts to 75 knots. A
few cumulonimbi with maximum tops to 600. Mean storm motion vector
24025.
...Guyer
Read more
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0451 PM CDT Tue Jun 30 2026
Valid 021200Z - 081200Z
...Synopsis...
Persistent troughing, enhanced flow aloft, and an established dry
airmass will maintain fire weather threats across the Great Basin
and Southwest through the work-week. Meanwhile, a strong ridge of
high pressure will continue to build across the central-eastern
CONUS through the forecast period, promoting widespread above normal
temperatures with mostly dry conditions. On Day 4/Friday, the
upper-level trough is forecast to weaken and transition much of the
U.S. into more zonal flow, while extended guidance depicts ridging
will build across northern Mexico and into the Southwest on Day
5/Saturday. This pattern will favor very dry and locally breezy
conditions across the western U.S., while chances of accumulating
precipitation may alleviate broader fire weather concerns across the
Southeast and Mid-Atlantic.
...Days 3-4/Thursday-Friday...
Enhanced southwesterly flow associated with persistent upper-level
troughing will sustain fire weather concerns across the Southwest,
Great Basin, and CO Rockies through the week with minimal to no
overnight humidity recoveries expected. As such, broad 40% Critical
probabilities have been maintained. Targeted 70% Critical
probabilities were introduced across far eastern UT into the
southern CO/northern NM mountains where terrain-induced gusty winds
and less than 15% RH will overlap extremely dry fuels. Isolated dry
thunderstorm potential on Day 1/Tuesday could result in lightning
holdovers across north-central NM and south-central CO, which may
emerge as a result of consecutive days of hot, dry, and breezy
conditions.
High pressure will build in from the eastern CONUS this weekend,
with ensemble guidance depicting the ridge to amplify and strengthen
across the central U.S. sometime next week. This may encourage
southerly flow aloft to commence, conceivably bringing our first
chances at monsoonal moisture across the Desert Southwest. Trends
will be monitored for dry thunderstorm potential as predictability
increases and guidance resolves the evolution of the overall
synoptic pattern. Nevertheless, until sufficient moisture arrives, a
critically dry, long-lasting airmass and hot daytime temperatures
will reinforce localized fire weather concerns throughout the
Intermountain West.
..Elizalde-Garcia.. 06/30/2026
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0257 PM CDT Tue Jun 30 2026
Valid 302000Z - 011200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF WESTERN KANSAS...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHERN
HIGH PLAINS TO THE GREAT LAKES AND PARTS OF NEW ENGLAND...
...SUMMARY...
Scattered severe thunderstorms are still expected across parts of
the central High Plains, with severe wind gusts (60 to 85 mph) being
the primary hazard during the late afternoon and evening. Other
severe thunderstorms are still expected across the Great Lakes and
Northeast, as well as broader parts of the central Plains to middle
Missouri Valley.
...20Z Update...
The most noteworthy change made to the Day 1 Outlook for the 20Z
update was to join the two Slight Risk areas, driven by wind
probabilities, across the Plains to the Great Lakes. Furthermore,
the CIG1 area was expanded northeast into the Upper MS Valley.
Guidance consensus has consistently depicted a persistent region of
likely cold-pool-driven convection propagating around the upper
ridge periphery, from the central Plains this evening, toward the
Great Lakes through 12Z tomorrow morning. Uncertainty remains
regarding the overall morphology and evolution of this convection,
hence the constraining of severe wind probabilities to Category
2/Slight risk. However, overnight storms will traverse an elongated
axis of strong buoyancy, characterized by 8-9 C/km 700-500 mb lapse
rates atop 70+ F surface dewpoints (per 18Z OAX and GRB observed
soundings), along with forecast 30-40 kts of effective bulk shear.
As such, if more organized storm modes (particularly bow echoes) can
develop tonight, a couple of 75+ mph gusts could occur.
Otherwise, the previous forecast remains on track, with mainly minor
changes made to thunder and severe probabilities to reflect the
consensus among the latest observations and numerical guidance.
..Squitieri.. 06/30/2026
.PREV DISCUSSION... /ISSUED 1150 AM CDT Tue Jun 30 2026/
...Southern/Central Plains...
Scattered thunderstorms are forecast later this afternoon over the
High Plains on the western rim of richer low-level moisture and
strong insolation. Model guidance shows considerable erosion of the
capping layer by mid-afternoon with MLCAPE ranging from 1500 J/kg
over the Texas South Plains to 3500 J/kg over western Kansas.
Initially higher-based convection will gradually move east into
richer moisture and promote larger thunderstorm cores and increased
potential for storm clusters to develop. Large hail will be possible
with any initial supercell activity (i.e., most probable from the
northern Texas Panhandle into Kansas; 25-40 kt effective shear).
However, very steep surface to 300-mb lapse rates will favor strong
evaporative cooling with the more intense cores. Ample deep-layer
shear will exist for organized storms, but veering/backing of flow
with height will aid in storm outflow aggregating as linear clusters
become the primary storm mode with time. These organized but linear
clusters will likely be efficient in promoting severe wind gusts
(60-85 mph) during the early evening, coincident with a
strengthening LLJ and WAA before this threat wanes by late evening.
Weaker deep-layer shear farther south in the southern High Plains
will likely limit both storm organization and overall coverage of
the wind risk.
Later into this evening, confidence has increased in mainly
nocturnal development in a post-frontal environment, that will
probably have its genesis by early evening in the vicinity of
northeast Colorado/southwest Nebraska. These storms will likely
increase/expand northeastward tonight with large hail and damaging
wind potential, which could actually increase and become somewhat
more prominent overnight across northern Nebraska/southeast South
Dakota and neighboring Siouxland as storms cluster and as the warm
front quickly shifts northward regionally.
...Upper Midwest/Great Lakes...
A few strong storms could occur early this afternoon across northern
Michigan, but primary concern is the potential for redevelopment
later today, potentially focused along a zone of modifying
outflow/differential heating, with robust instability to the south.
Although the degree of mid-level capping is a key uncertainty, where
storms do redevelop, ample tropospheric flow will support organized
storms, including supercells capable primarily of a hail/wind risk
and perhaps a tornado. Storms will likely become more probable and
increase this evening with at least some hail and wind potential
continuing tonight.
...Northeast States...
A cluster of storms over southeast Ontario at midday will likely
continue to progress southeastward over Lake Ontario toward northern
New York today. See Mesoscale Discussion 1396 for additional
details. These storms coincide with a 30-40 kt belt of northwesterly
mid-level flow that resides on the immediate periphery of a
gradually building upper-level ridge and associated elevated mixed
layer. Residual cloud cover, via overnight/pre-dawn decayed
convection, casts a bit of uncertainty regarding boundary layer
destabilization over portions of this region, especially with
northeastward extent. Nonetheless, increasing storm
coverage/intensity is expected this afternoon including
clusters/bowing segments and possibly a few supercells.
...Southeast...
Located to the south of an upper high centered over the Tennessee
Valley, a very moist air mass is present across much of the region.
Strong heating will yield moderate buoyancy by early afternoon.
Forecast soundings depict around 20-kt effective shear which will
aid in minor multicellular organization. Localized 50-60 mph gusts
capable of isolated wind damage will accompany the stronger storms.
Read more
MD 1393 CONCERNING SEVERE THUNDERSTORM WATCH 421... FOR SOUTHERN MN INTO NORTHERN IA
Mesoscale Discussion 1393
NWS Storm Prediction Center Norman OK
0404 AM CDT Tue Jun 30 2026
Areas affected...Southern MN into northern IA
Concerning...Severe Thunderstorm Watch 421...
Valid 300904Z - 301030Z
The severe weather threat for Severe Thunderstorm Watch 421
continues.
SUMMARY...At least localized severe gusts remain possible through
dawn.
DISCUSSION...Convection associated with a storm cluster over
south-central MN has recently weakened, with CINH tending to weaken
storms along the southern part of the cluster, and more stable
conditions to the north of a frontal boundary constraining
development within the northern part of the cluster. However, strong
to severe gusts continue to be observed, most recently a 52 kt gust
at KJYG in Watonwan County, MN.
Downstream of this cluster, a more favorable environment remains in
place into southeast MN and southwest WI, with MUCAPE of near/above
4000 J/kg and weaker CINH per recent objective mesoanalyses. Even if
the ongoing cluster continues to weaken, some redevelopment and
possible reorganization cannot be ruled out as the primary gust
front/cold pool move into this environment. Some intensification of
trailing convection across northwest IA also remains possible as it
moves east-northeastward through the early morning.
..Dean.. 06/30/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...ARX...MPX...DMX...FSD...
LAT...LON 44209496 44209496 44859439 45089397 45109341 44989286
44919259 44659227 44129194 43599197 43359231 43309288
43179465 43509497 43809498 43999496 44209496
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
Read more
Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0338 AM CDT Tue Jun 30 2026
Valid 031200Z - 081200Z
...DISCUSSION...
Upper-level flow is expected to become more zonal across the CONUS
this Friday. The upper ridge within the East will lose amplitude and
develop westward and amplify once again into early next week. The
exact structure of the upper ridge does vary within model guidance.
At the surface, a mostly stationary boundary will continue to be
modified/reinforced by convection occurring along/near it on
preceding days. As the upper ridge builds in the West, this boundary
will likely get pushed farther south within the areas east of the
Mississippi by the developing surface high in the Upper
Midwest/Great Lakes. Moisture will then be transported farther
north/west in the Plains/High Plains beginning sometime this
weekend. The general theme for the extended forecast will be where
subtle shortwaves/MCVs will propagate and spur convection along the
boundary.
For Friday, another MCS is possible along the surface boundary
similar to D3/Thursday. Uncertainty in how Thursday's convection
will impact the location of the boundary and most favorable
environment reduces confidence on where the greatest severe threat
will be. Into the weekend and early next week, some severe threat is
possible in parts of the eastern CONUS in association with MCV from
convection in the Plains/Midwest. Additional severe storms could
occur as northwesterly flow aloft develops in the High Plains. There
are still enough differences in the upper-level pattern between
medium range guidance that predictability of any higher threat
corridors is low.
Read more
Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0338 AM CDT Tue Jun 30 2026
Valid 031200Z - 081200Z
...DISCUSSION...
Upper-level flow is expected to become more zonal across the CONUS
this Friday. The upper ridge within the East will lose amplitude and
develop westward and amplify once again into early next week. The
exact structure of the upper ridge does vary within model guidance.
At the surface, a mostly stationary boundary will continue to be
modified/reinforced by convection occurring along/near it on
preceding days. As the upper ridge builds in the West, this boundary
will likely get pushed farther south within the areas east of the
Mississippi by the developing surface high in the Upper
Midwest/Great Lakes. Moisture will then be transported farther
north/west in the Plains/High Plains beginning sometime this
weekend. The general theme for the extended forecast will be where
subtle shortwaves/MCVs will propagate and spur convection along the
boundary.
For Friday, another MCS is possible along the surface boundary
similar to D3/Thursday. Uncertainty in how Thursday's convection
will impact the location of the boundary and most favorable
environment reduces confidence on where the greatest severe threat
will be. Into the weekend and early next week, some severe threat is
possible in parts of the eastern CONUS in association with MCV from
convection in the Plains/Midwest. Additional severe storms could
occur as northwesterly flow aloft develops in the High Plains. There
are still enough differences in the upper-level pattern between
medium range guidance that predictability of any higher threat
corridors is low.
Read more
WW 421 SEVERE TSTM IA MN WI 300800Z - 301500Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 421
NWS Storm Prediction Center Norman OK
300 AM CDT Tue Jun 30 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Northern Iowa
Southern and Southeast Minnesota
Western and West-Central Wisconsin
* Effective this Tuesday morning from 300 AM until 1000 AM CDT.
* Primary threats include...
Scattered damaging winds and isolated significant gusts to 75
mph possible
Isolated large hail events to 1 inch in diameter possible
SUMMARY...A cluster of severe thunderstorms will move into the Watch
area tonight and likely move east-northeast across the Watch area
through the early to mid morning. The linear cluster will pose a
risk for scattered severe gusts (60 to 75 mph).
The severe thunderstorm watch area is approximately along and 55
statute miles north and south of a line from 20 miles west northwest
of Fairmont MN to 50 miles east of Eau Claire WI. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU1).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 420...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1 inch. Extreme turbulence and surface wind gusts to 65 knots. A few
cumulonimbi with maximum tops to 550. Mean storm motion vector
24045.
...Smith
Read more
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0234 AM CDT Tue Jun 30 2026
Valid 021200Z - 031200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE BLACK
HILLS VICINITY INTO PARTS OF THE MIDWEST...
...SUMMARY...
Strong to severe storms will be possible from the northern Plains
into the Midwest and Great Lakes regions on Thursday. Isolated
strong to severe storms may also occur in the Tennessee
Valley/Southeast as well as parts of the Northeast.
...Synopsis...
Upper ridging will continue in the East with broad cyclonic flow in
the West. Embedded shortwave troughs will likely impact the northern
Plains. Another shortwave trough embedded within northwesterly flow
aloft will move into parts of the Northeast. A stalled surface
boundary will be present from the northern High Plains into the
Upper Midwest with a lee trough/weak surface low developing in the
High Plains.
...Black Hills into Iowa/Minnesota...
A subtle shortwave trough is evident in model guidance. This feature
will move into Wyoming/Montana and eventually the western Dakotas.
Convection appears likely to develop within the higher terrain (Big
Horns/Black Hills) and move into an airmass with increasingly rich
low-level moisture to the east. Convection should be able to
organize along the surface boundary with around 40 kt of effective
shear parallel to the boundary itself. Additional convection is also
possible along the stationary front as low-level warm advection
increases. Though there is some variability in where any eventual
MCS will propagate, there is enough confidence to include a 15%
severe probability area that encompasses the envelope of potential
tracks. The environment would support significant hail with
supercells and significant winds with an organized MCS.
...Northeast...
Ahead of a cold front attendant from a surface low in Quebec,
convection will be possible during the afternoon. The timing of the
convection, and thus the available buoyancy, is not entirely
certain. Damaging wind gusts and large hail would be possible.
...Tennessee Valley into Southeast...
A subtle easterly wave rotating around the upper anticyclone will
promote afternoon convection within a very moist and unstable
airmass. Given the mid-level lapse rates will fairly steep, storms
will likely be capable of damaging downburst winds despite weak
shear.
..Wendt.. 06/30/2026
Read more
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0234 AM CDT Tue Jun 30 2026
Valid 021200Z - 031200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE BLACK
HILLS VICINITY INTO PARTS OF THE MIDWEST...
...SUMMARY...
Strong to severe storms will be possible from the northern Plains
into the Midwest and Great Lakes regions on Thursday. Isolated
strong to severe storms may also occur in the Tennessee
Valley/Southeast as well as parts of the Northeast.
...Synopsis...
Upper ridging will continue in the East with broad cyclonic flow in
the West. Embedded shortwave troughs will likely impact the northern
Plains. Another shortwave trough embedded within northwesterly flow
aloft will move into parts of the Northeast. A stalled surface
boundary will be present from the northern High Plains into the
Upper Midwest with a lee trough/weak surface low developing in the
High Plains.
...Black Hills into Iowa/Minnesota...
A subtle shortwave trough is evident in model guidance. This feature
will move into Wyoming/Montana and eventually the western Dakotas.
Convection appears likely to develop within the higher terrain (Big
Horns/Black Hills) and move into an airmass with increasingly rich
low-level moisture to the east. Convection should be able to
organize along the surface boundary with around 40 kt of effective
shear parallel to the boundary itself. Additional convection is also
possible along the stationary front as low-level warm advection
increases. Though there is some variability in where any eventual
MCS will propagate, there is enough confidence to include a 15%
severe probability area that encompasses the envelope of potential
tracks. The environment would support significant hail with
supercells and significant winds with an organized MCS.
...Northeast...
Ahead of a cold front attendant from a surface low in Quebec,
convection will be possible during the afternoon. The timing of the
convection, and thus the available buoyancy, is not entirely
certain. Damaging wind gusts and large hail would be possible.
...Tennessee Valley into Southeast...
A subtle easterly wave rotating around the upper anticyclone will
promote afternoon convection within a very moist and unstable
airmass. Given the mid-level lapse rates will fairly steep, storms
will likely be capable of damaging downburst winds despite weak
shear.
..Wendt.. 06/30/2026
Read more
