WW 205 SEVERE TSTM IA MN NE SD 152215Z - 160600Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 205
NWS Storm Prediction Center Norman OK
515 PM CDT Fri May 15 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Western into Central and Northern Iowa
Southern Minnesota
Eastern Nebraska
Far Southeast South Dakota
* Effective this Friday afternoon and Saturday morning from 515
PM until 100 AM CDT.
* Primary threats include...
Scattered damaging winds and isolated significant gusts to 80
mph likely
Scattered large hail and isolated very large hail events to 3.5
inches in diameter likely
A tornado or two possible
SUMMARY...Thunderstorms are forecast to develop and intensify early
this evening. Supercells capable of very large hail are expected
initially (diameters between 2.5 to 3.5 inches). A tornado or two
is possible later this evening. Upscale growth into one or two
bands or bowing segments is expected later this evening with severe
wind gusts becoming more prevalent. Peak gusts associated with the
thunderstorm bands will probably range 70-80 mph.
The severe thunderstorm watch area is approximately along and 95
statute miles north and south of a line from 60 miles southeast of
Rochester MN to 5 miles north of Columbus NE. 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 204...
AVIATION...A few severe thunderstorms with hail surface and aloft to
3.5 inches. Extreme turbulence and surface wind gusts to 70 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
27030.
...Smith
WW 204 SEVERE TSTM TX 152035Z - 160300Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 204
NWS Storm Prediction Center Norman OK
335 PM CDT Fri May 15 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
West and Southwest Texas
* Effective this Friday afternoon and evening from 335 PM until
1000 PM CDT.
* Primary threats include...
Scattered damaging winds likely with isolated significant gusts
to 75 mph possible
Isolated large hail events to 1 inch in diameter possible
SUMMARY...High-based thunderstorms will develop through late
afternoon with an increasing potential for severe-caliber wind
gusts/downbursts, and possibly some hail.
The severe thunderstorm watch area is approximately along and 60
statute miles east and west of a line from 40 miles north northeast
of Plainview TX to 65 miles southeast of Fort Stockton TX. 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.
&&
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 500. Mean storm motion vector
27025.
...Guyer
WW 0205 Status Updates
STATUS FOR WATCH 0205 HAS NOT BEEN ISSUED YET
WW 0204 Status Updates
STATUS REPORT ON WW 204
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..SQUITIERI..05/15/26
ATTN...WFO...MAF...LUB...SJT...
STATUS REPORT FOR WS 204
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
TXC003-017-033-045-069-075-079-101-103-105-107-115-125-135-151-
153-165-169-173-189-191-219-227-235-263-269-279-303-305-317-329-
335-345-369-371-383-415-431-433-437-443-445-461-501-152340-
TX
. TEXAS COUNTIES INCLUDED ARE
ANDREWS BAILEY BORDEN
BRISCOE CASTRO CHILDRESS
COCHRAN COTTLE CRANE
CROCKETT CROSBY DAWSON
DICKENS ECTOR FISHER
FLOYD GAINES GARZA
GLASSCOCK HALE HALL
HOCKLEY HOWARD IRION
KENT KING LAMB
LUBBOCK LYNN MARTIN
MIDLAND MITCHELL MOTLEY
PARMER PECOS REAGAN
SCURRY STERLING STONEWALL
SWISHER TERRELL TERRY
UPTON YOAKUM
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
MD 0727 CONCERNING SEVERE THUNDERSTORM WATCH 204... FOR PORTIONS OF WESTERN TEXAS
Mesoscale Discussion 0727
NWS Storm Prediction Center Norman OK
0601 PM CDT Fri May 15 2026
Areas affected...portions of western Texas
Concerning...Severe Thunderstorm Watch 204...
Valid 152301Z - 160030Z
The severe weather threat for Severe Thunderstorm Watch 204
continues.
SUMMARY...Severe gusts will remain a concern through the afternoon
and evening hours.
DISCUSSION...Clusters of high-based thunderstorms, with a history of
isolated measured severe (50+ kt) convective gusts, continues to
progress eastward across western TX, amid a deeply mixed, unstable
boundary layer. Congealing outflows have been noted via KLBB
reflectivity data across the TX Panhandle, where blowing dust with
zero visibility have also been reported. Scattered high-based cells
will continue to develop along this outflow, and with more robust CU
closer to the TX Rolling Plains over the next couple of hours. As
long as the deep and mixed boundary layer remains in place, any of
the stronger storm cores in this environment may support erratic
strong to severe gusts.
..Squitieri.. 05/15/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...SJT...LUB...MAF...
LAT...LON 30460305 34240296 34600265 34690163 34530070 34140039
33410034 32050060 31040089 30490149 30200206 30230265
30460305
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MD 0726 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR WESTERN AND CENTRAL WISCONSIN INTO THE WESTERN UP OF MICHIGAN
Mesoscale Discussion 0726
NWS Storm Prediction Center Norman OK
0541 PM CDT Fri May 15 2026
Areas affected...western and central Wisconsin into the western UP
of Michigan
Concerning...Severe potential...Watch possible
Valid 152241Z - 160045Z
Probability of Watch Issuance...40 percent
SUMMARY...The threat for large hail and/or strong to severe wind
gusts is expected to increase this evening. Greatest storm coverage
and attendant severe-weather risk is expected across southwest
Wisconsin, with decreasing severe-weather potential with
northeastward extent into the western UP of Michigan. Convective
trends are being monitored for a possible watch.
DISCUSSION...Early-evening visible satellite shows a growing cumulus
field from west-central into north-central WI, ahead of a weak cold
front moving into the northwest part of the state. The
boundary-layer remains relatively dry with dewpoints largely in the
40s. However, the presence of steep low/mid-level lapse rates is
resulting in a marginally unstable air mass across west-central into
southwest WI with MUCAPE of 500-1000 J/kg.
Latest short-term model guidance is suggestive that isolated to
widely scattered thunderstorms may emerge from the deepening cumulus
field west through north of La Crosse within the next hour or two
with additional, more isolated storm development possible across the
WI North Woods into the western UP of MI, along and ahead of the
front. Despite the loss of diurnal insolation, increasing
boundary-layer moisture content along a strengthening low-level jet
is expected to support additional air mass destabilization this
evening amid a kinematic environment featuring vertically veering
wind profiles with strengthening deep-layer shear with northward
extent across the discussion area. As such, the potential exists for
some storm organization with an associated risk for large hail
and/or locally strong to severe wind gusts. Convective trends are
being monitored for a possible Severe Thunderstorm Watch.
..Mead/Smith.. 05/15/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MQT...GRB...MKX...DLH...ARX...MPX...
LAT...LON 44709199 45809138 46319017 46428936 46508838 46098790
45298848 42948944 42669002 42759077 43659102 44159158
44709199
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
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0258 PM CDT Fri May 15 2026
Valid 152000Z - 161200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF IOWA...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER
MIDWEST AND CENTRAL/SOUTHERN PLAINS....
...SUMMARY...
Severe thunderstorms capable of producing severe/damaging winds and
large to very large hail are likely late this afternoon and evening
centered across much of Iowa. Isolated to scattered severe hail and
damaging winds are possible over a broader area from parts of the
southern High Plains to the Upper Midwest.
...20z Update Central Plains...
Several areas of thunderstorm development are expected this
afternoon and evening across the central Plains and Midwest.
Moderate instability beneath 40+ kt of mid-level flow will promote a
mixed mode of supercells and eventually linear clusters. Hail (some
2+ inches) along with damaging gusts appear likely with the more
robust supercells initially along the cold front across NE/northern
KS, and farther north along the warm front into southern MN.
Eventual upscale growth into one or more linear clusters should
favor an increase in the threat for damaging gust and a couple
tornadoes over parts of IA, IL and southern WI this evening.
...Eastern NM/CO and the TX/OK Panhandles...
Initial high-based shower and thunderstorm development is underway
coincident with very strong heating and the arrival of a weak
upper-level shortwave trough atop the well-mixed air mass west of
the dryline. With mixing depths of 4-5 km below modest buoyancy,
strong to severe gusts are possible with these showers and
thunderstorms across the southern High Plains. Wind probabilities
were shifted slightly west. See MCDs #723 and #724 for short term
information.
..Lyons.. 05/15/2026
.PREV DISCUSSION... /ISSUED 1129 AM CDT Fri May 15 2026/
...Central Plains into the Upper Midwest including Iowa...
A cyclonically influenced moderately strong belt of westerlies will
exist over the northern Plains to Upper Midwest and upper Great
Lakes. The primary surface low will remain in northern Ontario, with
a trailing cold front extending southward into the Upper Midwest and
northern/central Plains. A secondary surface low will exist across
southwest Kansas and northwest Oklahoma around peak afternoon
heating, with a dryline extending south-southwestward from this low
across much of the southern High Plains.
Continued expectations are for robust thunderstorm development along
the cold front/surface trough from eastern Nebraska into Iowa to be
delayed until late afternoon or early evening (around 22-00Z), as
large-scale ascent will remain weak until a low-amplitude shortwave
trough embedded within the westerly mid-level flow eventually
overspreads the surface warm sector. Continued low-level warm/moist
advection through the day and diurnal heating will contribute to the
development of moderate to locally strong instability (2500+ J/kg
MLCAPE) across this region by early evening. While low-level winds
are forecast to remain fairly modest, enhanced mid/upper-level flow
will support sufficient (35-50 kt) deep-layer shear for updraft
organization.
Initial supercells should pose a threat for large to isolated very
large hail (2+ inches in diameter), before likely quick upscale
growth this evening across Iowa with an increasing potential for
scattered severe/damaging winds. Some of these gusts could exceed 75
mph on a localized basis given the expectation for an organized
cluster and ample instability. A tornado or two could also occur
this evening as low-level shear gradually increases with a
strengthening low-level jet.
...Southern High Plains...
While clouds linger at midday, particularly with southward extent
across west/southwest Texas, robust daytime heating will yield a
very well-mixed/deep boundary layer near/south of the secondary
surface low over southwest Kansas/northwest Oklahoma. Mid-level
temperatures will remain cool enough to support at least weak
instability, even with modest low-level moisture/surface dewpoints.
A weak mid-level shortwave trough moving from the southern Rockies
into the southern High Plains will enhance large-scale ascent late
in the day. This should support the development of high-based
thunderstorms, with occasional strong to severe wind gusts expected.
Latest short-term guidance suggests a more probable zone of
thunderstorm-related gust potential may focus across the Texas South
Plains and Low Rolling Plains. Isolated gusts of 70+ mph may occur
given the very deeply mixed boundary layer extending up to around
500 mb. Cells that develop in west/southwest Texas may also contain
some hail, with elongated hodographs in mid/upper levels.
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0229 PM CDT Fri May 15 2026
Valid 171200Z - 181200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM CENTRAL
NEBRASKA TO SOUTHWEST MINNESOTA...
...SUMMARY...
Severe storms are expected Sunday afternoon into Sunday night from
portions of the central Plains into the Upper Midwest. Supercells
with very large hail and tornadoes are possible, before upscale
storm growth leads to an increase in the wind damage threat.
...Synopsis...
The primary midlevel trough over the northern Great Basin Sunday
morning will progress to the Four Corners by Monday morning. A
subtle, lead shortwave trough (now over northern CA) will eject
northeastward during the day from NM to western KS/central NE, and
it will reach MN by early Monday. A weak reflection of the initial
lee cyclone will likewise move north-northeastward across NE to MN,
along a pre-existing baroclinic zone. The boundary layer will
consist mostly of roughly mid 60s dewpoints east of the dryline and
south of the warm front Sunday, while the fully modified (maritime
tropical) air mass will return to TX through Sunday night.
...NE to MN...
The elevated remnants of overnight convection across NE/IA, and an
associated MCV, should move northeastward toward the upper MS Valley
and weaken. In the wake of the early convection, surface heating in
cloud breaks will contribute to destabilization and storm
development will become probable by Sunday afternoon/evening along
the stalled front in NE, in advance of the weak surface cyclone and
subtle/ejecting midlevel trough. Mesoscale details are fairly
uncertain this far in advance. Still, the forecast environment
appears favorable for initial supercells with very large hail and
tornadoes, and some increase in the threat for damaging winds as
convection grows upscale along the front and spreads northeastward
into southeast SD, northwest IA and southwest MN through Sunday
night.
...Western KS to TX Panhandle dryline...
A relatively warm elevated mixed layer and no obvious forcing for
ascent both suggest that storm initiation will rely on sufficiently
deep mixing along the dryline, and that storm formation is very much
in question. If a storm or two forms late afternoon/evening before
the dryline retreats overnight, there be a conditional threat for
supercells with large hail.
..Thompson.. 05/15/2026
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0221 PM CDT Fri May 15 2026
Valid 161200Z - 171200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NEW MEXICO
INTO THE TEXAS PANHANDLE...
The Isolated Dry Thunder, Critical, and Elevated areas were expanded
very slightly to the south and east to accommodate the latest
forecast guidance, which indicates a slight eastward trend in the
placement of the dryline Day 2/Saturday afternoon. Additional minor
adjustments may be necessary as the dryline evolves. However, the
potential for lightning-ignited wildfires with multiple consecutive
days of dry and windy conditions before, during, and after will only
exacerbate the overall fire environment threat throughout this
period.
Over the central/northern Plains, while localized elevated wind/RH
will be possible over portions of western South Dakota on Day
2/Saturday, green up is expected to preclude any highlights in that
area. Amid southwest flow aloft and southeast winds at the surface
(eventually working to advect higher humidity into the region), the
areas of lowest RHs happen to coincide with some of the most green
vegetation. Additionally, some of this area is anticipated to
receive wetting precipitation with cloud cover also limiting solar
radiation and afternoon heating.
..Stearns.. 05/15/2026
.PREV DISCUSSION... /ISSUED 0201 AM CDT Fri May 15 2026/
...Synopsis...
A mid-level trough will amplify while traversing the Rockies,
resulting in a deepening surface low across the central Plains.
Similar to Day 1, another round of dry downslope flow is expected
behind a sharpening dryline across the southern High Plains. The
latest guidance consensus depicts widespread 20-25 mph sustained
southwesterly surface winds amid 15-20 percent RH across much of the
lower Colorado River Basin into the southern High Plains, hence the
introduction of broad Elevated highlights. Critical highlights have
been introduced across southeastern New Mexico into the Texas
Panhandle, where guidance consensus shows the aforementioned
meteorological surface conditions overspreading loaded fuels that
are most receptive to wildfire spread. Initial discrete thunderstorm
development across the Oklahoma and Texas Panhandles may initially
be high based as storms develop over a mixed boundary layer
immediately along the dryline. Given dry fuel beds,
lightning-induced fire ignitions are possible where storms first
develop, warranting the introduction of isolated dry thunderstorm
highlights.
...Please see www.spc.noaa.gov/fire for graphic product...
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0451 PM CDT Fri May 15 2026
Valid 171200Z - 231200Z
Quasi-zonal flow will prevail across a large portion of the eastern
US beginning Day 3/Sunday. Concurrently, a pronounced mid-level
trough is forecast to dig through the Intermountain West and lift
northeast across the Plains through the week. This evolution will
establish a prolonged period of Critical fire weather potential
across parts of the Southwest and southern High Plains. Medium-range
forecast guidance indicates the synoptic pattern will deamplify by
late next week, introducing lower confidence in fire weather threats
as a cooler airmass settles over much of the CONUS. By the following
weekend, surface temperatures begin to rebound back above normal
over the far western CONUS.
...Southwest/Southern Plains...
From Day 3/Sunday through Day 4/Monday, the previously mentioned
robust mid-level trough will drive a multi-day stretch of what will
likely become Elevated to Critical fire weather conditions spanning
the Southwest into the adjacent southern Plains. Warm temperatures
and dry antecedent conditions, driven by recent upper-level ridging,
support cured fuels and have primed the region for ignitions.
West-southwesterly surface winds are progged to sustain at 20-30
mph, overlapping with minimum relative humidity values falling into
the single digits to low teens for prolonged afternoon periods.
Forecast guidance continues to highlight poor overnight moisture
recovery, with RH values largely remaining below 30% through the
entire Day 2/Saturday through Day 4/Monday period. This will extend
active burn windows well into the overnight hours. By Day 5/Tuesday,
lingering stronger-than-typical daytime winds will contribute to
another day of potential fire weather concerns over the region,
albeit less intense than on Day 3/Sunday and Day 4/Monday.
...California...
On Day 4/Monday, tightening surface gradient flow supported by the
jet stream overhead behind the deepening Great Basin trough will
produce strong and dry northerly surface winds (sustained at 15-20
mph) across the CA Central Valley. When paired with afternoon
humidity dropping into the teens, receptive fine fuels, and an
unseasonably warm/dry airmass over the preceding days, the threat
for rapid fire spread remains evident. Therefore, 40% probabilities
have been retained to highlight this fire weather risk.
..Stearns.. 05/15/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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