RSS Mesoscale Discussions from Storm Prediction Center
WW 503 SEVERE TSTM IA NE 110045Z - 110700Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 503
NWS Storm Prediction Center Norman OK
745 PM CDT Thu Jul 10 2025
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Southwest Iowa
Southeast Nebraska
* Effective this Thursday night and Friday morning from 745 PM
until 200 AM CDT.
* Primary threats include...
Scattered damaging winds likely with isolated significant gusts
to 75 mph possible
Isolated very large hail events to 2 inches in diameter possible
A tornado or two possible
SUMMARY...Clusters of thunderstorms over Nebraska will track
eastward for the next several hours across the watch area. Locally
damaging wind gusts are the primary concern, although a few of the
storms may also pose a risk of large hail or even a tornado.
The severe thunderstorm watch area is approximately along and 55
statute miles north and south of a line from 30 miles west of
Lincoln NE to 10 miles east of Des Moines IA. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU3).
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 501...WW 502...
AVIATION...A few severe thunderstorms with hail surface and aloft to
2 inches. Extreme turbulence and surface wind gusts to 65 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
27030.
...Hart
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WW 502 SEVERE TSTM CO KS NE 102030Z - 110300Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 502
NWS Storm Prediction Center Norman OK
230 PM MDT Thu Jul 10 2025
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Eastern Colorado
Western and Central Kansas
Southwest and South-Central Nebraska
* Effective this Thursday afternoon and evening from 230 PM until
900 PM MDT.
* Primary threats include...
Scattered damaging winds and isolated significant gusts to 75
mph likely
Scattered large hail and isolated very large hail events to 2
inches in diameter possible
SUMMARY...Thunderstorm coverage is expected to increase across a
wide area from the Colorado Front Range into western Kansas and
south-central Nebraska this afternoon, with storms continuing into
the evening. Some isolated hail is possible with these storms,
particularly along the Front Range, but the primary severe hazard is
expected to be strong wind gusts. Some wind gusts to 75 mph are
possible.
The severe thunderstorm watch area is approximately along and 130
statute miles east and west of a line from 25 miles northeast of
Imperial NE to 15 miles east southeast of Elkhart KS. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU2).
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 501...
AVIATION...A few severe thunderstorms with hail surface and aloft to
2 inches. Extreme turbulence and surface wind gusts to 65 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
25025.
...Mosier
Read more
WW 501 TORNADO IA NE SD 102010Z - 110300Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 501
NWS Storm Prediction Center Norman OK
310 PM CDT Thu Jul 10 2025
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
Far Western Iowa
Northeast Nebraska
Extreme Southeast South Dakota
* Effective this Thursday afternoon and evening from 310 PM until
1000 PM CDT.
* Primary threats include...
A couple tornadoes possible
Scattered damaging winds and isolated significant gusts to 80
mph likely
Scattered large hail and isolated very large hail events to 2
inches in diameter likely
SUMMARY...Thunderstorm development is anticipated within the very
unstable airmass across central/northeast NE this afternoon.
Environmental conditions support initial supercells capable of all
severe hazards, including large to very large hail and tornadoes.
Upscale growth is anticipated after the initial cellular mode, with
the resultant convective line progressing quickly eastward. Strong
wind gusts are possible within this line, including gusts over 75
mph.
The tornado watch area is approximately along and 75 statute miles
north and south of a line from 5 miles north northwest of Broken Bow
NE to 10 miles east of Denison IA. For a complete depiction of the
watch see the associated watch outline update (WOUS64 KWNS WOU1).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and 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.
&&
AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 2 inches. Extreme turbulence and surface wind
gusts to 70 knots. A few cumulonimbi with maximum tops to 500. Mean
storm motion vector 27035.
...Mosier
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WW 0503 Status Updates
STATUS FOR WATCH 0503 HAS NOT BEEN ISSUED YET
Read more
WW 0502 Status Updates
STATUS REPORT ON WW 502
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM RTN TO 35
WSW SPD TO 10 NW LAA TO 35 NE LIC TO 45 ESE FCL.
..THORNTON..07/11/25
ATTN...WFO...BOU...PUB...GLD...DDC...GID...LBF...
STATUS REPORT FOR WS 502
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
COC009-011-017-061-063-075-087-095-099-115-121-125-110140-
CO
. COLORADO COUNTIES INCLUDED ARE
BACA BENT CHEYENNE
KIOWA KIT CARSON LOGAN
MORGAN PHILLIPS PROWERS
SEDGWICK WASHINGTON YUMA
KSC023-025-033-039-047-051-055-057-063-065-067-069-071-075-081-
083-093-097-101-109-119-129-135-137-141-145-147-153-163-165-171-
175-179-181-183-187-189-193-195-199-203-110140-
KS
. KANSAS COUNTIES INCLUDED ARE
CHEYENNE CLARK COMANCHE
DECATUR EDWARDS ELLIS
FINNEY FORD GOVE
GRAHAM GRANT GRAY
GREELEY HAMILTON HASKELL
HODGEMAN KEARNY KIOWA
LANE LOGAN MEADE
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WW 0501 Status Updates
STATUS REPORT ON WW 501
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..SPC..07/11/25
ATTN...WFO...OAX...FSD...LBF...GID...
STATUS REPORT FOR WT 501
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
IAC085-133-149-193-110140-
IA
. IOWA COUNTIES INCLUDED ARE
HARRISON MONONA PLYMOUTH
WOODBURY
NEC003-011-021-023-027-037-039-041-043-051-053-055-071-077-089-
093-107-115-119-121-125-139-141-143-149-153-155-163-167-173-175-
177-179-183-110140-
NE
. NEBRASKA COUNTIES INCLUDED ARE
ANTELOPE BOONE BURT
BUTLER CEDAR COLFAX
CUMING CUSTER DAKOTA
DIXON DODGE DOUGLAS
GARFIELD GREELEY HOLT
HOWARD KNOX LOUP
MADISON MERRICK NANCE
PIERCE PLATTE POLK
ROCK SARPY SAUNDERS
SHERMAN STANTON THURSTON
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MD 1636 CONCERNING SEVERE THUNDERSTORM WATCH 502... FOR EASTERN COLORADO...WESTERN KANSAS...FAR SOUTHERN NEBRASKA
Mesoscale Discussion 1636
NWS Storm Prediction Center Norman OK
0656 PM CDT Thu Jul 10 2025
Areas affected...eastern Colorado...western Kansas...far southern
Nebraska
Concerning...Severe Thunderstorm Watch 502...
Valid 102356Z - 110200Z
The severe weather threat for Severe Thunderstorm Watch 502
continues.
SUMMARY...Instances of severe wind and hail remain possible in
WW502.
DISCUSSION...Several clusters of storms continue across far eastern
CO into western KS/NE. Storms are within a region of increasing
MLCIN. Above the inversion, elevated instability remains for storms
rooted above the surface. Storms are likely elevated and will mainly
pose a risk for large hail, though some more surface based storms
may produce occasional severe winds, primarily across northeastern
Colorado where MLCIN is weaker and deep layer shear around 40-50 kts
remains for organization.
..Thornton.. 07/10/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LBF...DDC...GLD...AMA...PUB...BOU...ABQ...
LAT...LON 37080418 37680334 38190314 38590314 39080304 39210309
39850389 40230430 40460454 40850423 40820262 40670221
40420172 39920089 39030059 37690109 37060166 36610212
36440277 36450350 36560387 37080418
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
Read more
MD 1635 CONCERNING TORNADO WATCH 501... FOR EASTERN NEBRASKA...WESTERN IOWA
Mesoscale Discussion 1635
NWS Storm Prediction Center Norman OK
0645 PM CDT Thu Jul 10 2025
Areas affected...Eastern Nebraska...Western Iowa
Concerning...Tornado Watch 501...
Valid 102345Z - 110145Z
The severe weather threat for Tornado Watch 501 continues.
SUMMARY...Severe threat continues across eastern Nebraska into
western Iowa.
DISCUSSION...Short-wave ridging that has been observed over the
lower MO Valley is shifting east as a secondary, notable short-wave
trough is advancing across central SD/western NE. Low-level warm
advection is focused into this region, just north of a boundary that
is draped from south of Grand Island-Omaha-north of Des Moines. This
warm-advection regime favors rotation, and a few slow-moving
supercells can be expected in advance of the short wave this
evening. While some supercell structures are possible, with time
convection may evolve into larger clusters, and possibly an MCS. LLJ
is forecast to strengthen across northeast KS into southwest IA
later this evening, and this should encourage more robust convection
to propagate into this portion of the MO Valley with time.
..Darrow.. 07/10/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...DMX...FSD...OAX...GID...LBF...
LAT...LON 40409966 42579967 43069519 40889519 40409966
MOST PROBABLE PEAK TORNADO INTENSITY...85-115 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
Read more
MD 1634 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR EASTERN IA INTO NORTHERN ILLINOIS
Mesoscale Discussion 1634
NWS Storm Prediction Center Norman OK
0613 PM CDT Thu Jul 10 2025
Areas affected...Eastern IA into northern Illinois
Concerning...Severe potential...Watch unlikely
Valid 102313Z - 110115Z
Probability of Watch Issuance...20 percent
SUMMARY...Isolated hail/wind, and perhaps a brief tornado, are
possible across eastern Iowa into northern Illinois this evening.
Watch is not currently anticipated.
DISCUSSION...Low-amplitude short-wave trough is evident in
water-vapor imagery, very near the MS River, from southeast MN into
northwestern IL. Large-scale ascent ahead of this feature appears to
be aiding convection across northern IL, just north of a warm front
that is draped from south of Chicago to north of Dubuque IA.
Low-level warm advection is likely contributing to a few small,
slow-moving clusters north of the wind shift. Radar data suggests
this activity may be generating locally severe hail, and gusty
winds. Wind profiles are not that strong ahead of the short wave,
but veering profiles do suggest some rotation is possible.
Farther west across eastern IA, scattered thunderstorms have
developed just behind the trough within a more buoyant and stronger
sheared environment. At times a few updrafts have exhibited
supercell characteristics, but updrafts have struggled to organize
at times, possibly due to the passage of the short wave. Unless this
activity becomes more organized current thinking is the primary
concerns will be isolated hail/wind, and perhaps a brief tornado.
..Darrow/Hart.. 07/10/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LOT...ILX...MKX...DVN...ARX...DMX...
LAT...LON 42599148 42288778 41328786 41039052 40769277 42599148
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
Read more
SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0740 PM CDT Thu Jul 10 2025
Valid 110100Z - 111200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING INTO
TONIGHT ACROSS PARTS OF WESTERN/CENTRAL KANSAS....EASTERN
NEBRASKA...MUCH OF IOWA...PARTS OF NWRN ILLINOIS...
...SUMMARY...
Scattered strong to severe thunderstorm development remains possible
this evening across parts of the central Great Plains into Upper
Midwest. This could still include a slowly organizing cluster of
storms with potential for strong to severe surface gusts across the
eastern Nebraska into Iowa vicinity.
...01Z Update...
A belt of 20-30+ kt southerly/westerly lower/mid-tropospheric flow
across parts of the central Great Plains into portions of the Upper
Midwest may continue to enhance convective development, at least a
bit, this evening into the overnight hours. In mid-levels, this
includes flow augmented by convectively generated cyclonic
circulations, but, in lower-levels, this includes a
south-southwesterly low-level jet associated with weak mid-level
troughing digging east-southeast of the Wyoming/Colorado Rockies.
The low-level jet appears to be focusing a corridor of stronger warm
advection across parts of south central through eastern Nebraska,
where convective development may still consolidate and grow upscale
this evening. Perhaps aided by forcing associated with the synoptic
perturbation, or another evolving MCV, it might not be out of the
question that activity may slowly organize and acquire increasing
inflow of seasonably moist boundary-layer air characterized by
sizable CAPE as it tends to propagate eastward overnight. If this
occurs, there appears potential for sufficient intensification to
support an increasing risk for strong to severe surface gusts.
..Kerr.. 07/11/2025
Read more
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0259 PM CDT Thu Jul 10 2025
Valid 102000Z - 111200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PARTS OF
THE MID-MISSOURI VALLEY...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN
COLORADO INTO THE CENTRAL PLAINS AND PORTIONS OF IOWA...
...SUMMARY...
Severe thunderstorms capable of large hail, damaging winds, and
perhaps a couple of tornadoes are possible late this afternoon into
tonight across parts of the central Great Plains to the Midwest,
particularly across the Middle Missouri Valley. Additional severe
storms are expected across parts of the Northeast and Southeast.
...20Z Update...
In the wake of MCV moving into western Wisconsin, a belt of stronger
shear is evident where modest northwesterly flow aloft is positioned
over surface southeasterly winds in central/eastern Iowa.
Furthermore, temperatures have risen into the upper 80s/low 90s F.
Given the potential for widely scattered to scattered storms to
develop on the southwestern flank of the MCV, the Slight risk has
been expanded into more of eastern Iowa. The remainder of the
outlook is unchanged. See the previous discussion for additional
details.
..Wendt.. 07/10/2025
.PREV DISCUSSION... /ISSUED 1133 AM CDT Thu Jul 10 2025/
...Central High Plains through the Central Plains into IA...
Recent surface analysis places a low near the NE/CO border, with a
moist airmass ahead of it over the central Plains. Satellite imagery
also shows a shortwave trough moving through the Great Basin towards
the central High Plains. Both of these features are expected to move
eastward throughout the day, with the surface low contributing to
eventual convective initiation over far southeast SD/northeast NE
and northwest IA this afternoon. The shortwave is expected to result
in numerous thunderstorms over the high terrain, with these storms
then moving eastward into the central High Plains.
The thunderstorms that develop near the surface low will encounter a
strongly unstable and moderately sheared environment supportive of
initial supercells capable of all severe hazards, including very
large hail and tornadoes. This activity should quickly grow upscale,
with the resulting convective line pushing southeastward into more
of northeast NE and western IA. Given ample buoyancy downstream,
some significant wind gusts are possible as this line moves
eastward/southeastward.
Farther west, the thunderstorms moving into the central High Plains
will initially be high-based and capable of strong wind gusts as
they move into the very deeply mixed airmass downstream. Some
amalgamation along cold pools is possible here over time, with the
resulting convective line likely moving eastward across
south-central NE and central KS. Damaging gusts will be possible as
this line moves eastward.
...Mid MS Valley...
A well-defined MCV is currently moving across southern MN, with the
expectation that it will continue gradually eastward throughout the
day. Daytime heating along the southern/southeastern periphery of
this vorticity max will likely result in airmass destabilization and
moderate buoyancy from eastern IA into southern WI and northern IL
this afternoon. Mesoscale ascent attendant to the MCV will interact
with this airmass, likely resulting in thunderstorm development. Low
to mid-level flow enhanced by the MCV will result in moderate
vertical shear and the potential for a few supercells. Given the
mesoscale nature of this scenario, overall storm coverage, including
the supercell coverage, is uncertain. Any supercells that do develop
could result in a threat for all severe hazards, including large
hail and a brief tornado. Conditionality of the overall scenario
merits only low severe probabilities for now, but higher
probabilities maybe needed for the 20Z if trends merit.
...New England and Upper Ohio Valley...
A shortwave trough currently is moving through the base of the
larger cyclone over central/eastern ON. This shortwave is forecast
to continue eastward throughout the day, resulting in broad ascent
from the Upper OH Valley into New England. Scattered thunderstorm
development is probable during peak afternoon heating, as this wave
interacts with moderate buoyancy and vertical shear. A predominantly
multicellular mode is anticipated, with damaging winds and isolated
hail as the primary risks. A corridor of slightly better low-level
moisture is expected over the Champlain Valley vicinity, which could
result in both greater storm coverage and stronger, more long-lived
updrafts. As a result, there is a small area where higher severe
coverage is possible.
...Southeast/Southern Atlantic Seaboard...
A very moist airmass is in place across the Southeast and southern
Atlantic Seaboard. Recent surface analysis reveals dewpoints in the
low to mid 70s areawide. 12Z soundings at FFC, JAX, and CHS sampled
PW values of 1.91", 1.97", and 2.14", respectively. This ample
low-level moisture will help support airmass destabilization and
moderate to strong buoyancy as temperatures increase into the upper
80s and low 90s this afternoon. Subtle ascent along the southern
periphery of broad upper troughing will interact with this unstable
and buoyant airmass to support scattered strong to severe
thunderstorms this afternoon through early/mid-evening.
Vertical shear across the region will be very weak, resulting in an
outflow-dominant storm mode, with new development then occurring
along these outflows. Water-loaded downbursts will be the primary
hazard as these clusters gradually move southeastward over time.
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