WW 216 TORNADO IA MN 172310Z - 180600Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 216
NWS Storm Prediction Center Norman OK
610 PM CDT Sun May 17 2026
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
Northern Iowa
Southern Minnesota
* Effective this Sunday night and Monday morning from 610 PM
until 100 AM CDT.
* Primary threats include...
A few tornadoes and a couple intense tornadoes possible
Widespread 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...Scattered severe thunderstorms will move into the Watch
area from the west this evening. The stronger thunderstorms will
include supercells and intense thunderstorm clusters, which will
yield a risk for tornadoes (perhaps a strong tornado), large hail,
and scattered severe gusts. An organized band of severe
thunderstorms is eventually forecast to develop and move east across
the Watch later this evening. Severe gusts and a QLCS tornado are
possible with this activity.
The tornado watch area is approximately along and 70 statute miles
east and west of a line from 20 miles east northeast of Mankato MN
to 40 miles south southwest of Mason City IA. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU6).
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.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 213...WW 214...WW 215...
AVIATION...Tornadoes and 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 26030.
...Smith
WW 215 SEVERE TSTM CO KS NE 172155Z - 180200Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 215
NWS Storm Prediction Center Norman OK
455 PM CDT Sun May 17 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Eastern Colorado
Northwest Kansas
Southwest Nebraska
* Effective this Sunday afternoon and evening from 455 PM until
900 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
SUMMARY...A few severe thunderstorms are possible late this
afternoon and early evening within the Watch area. This activity
will likely progress eastward with the stronger storms capable of
severe gusts (60-70 mph) and large hail (1 to 2 inches in diameter).
The severe thunderstorm watch area is approximately along and 50
statute miles north and south of a line from 50 miles west northwest
of Burlington CO to 50 miles east northeast of Goodland KS. 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 213...WW 214...
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 400. Mean storm motion vector
27035.
...Smith
WW 214 TORNADO IA KS NE 172010Z - 180400Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 214
NWS Storm Prediction Center Norman OK
310 PM CDT Sun May 17 2026
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
Far Southwest Iowa
North-Central and Northeast Kansas
Southeast Nebraska
* Effective this Sunday afternoon and evening from 310 PM until
1100 PM CDT.
* Primary threats include...
A few tornadoes likely with a couple intense tornadoes possible
Scattered damaging winds likely with isolated significant gusts
to 75 mph possible
Scattered large hail likely with isolated very large hail events
to 3 inches in diameter possible
SUMMARY...The airmass ahead of the approaching cold front from
southeast Nebraska into north-central/northeast Kansas continues to
destabilize amid strong heating and low-level moisture advection.
Discrete thunderstorm development is possible in the warm sector
ahead of this cold front, with the environmental conditions
supportive of supercells capable of all hazards, including very
large hail to 3" in diameter and strong tornadoes. Thunderstorm
development is possible along the front as well, with large hail and
damaging gusts as the primary hazards with these storms.
The tornado watch area is approximately along and 95 statute miles
east and west of a line from 10 miles north northeast of Columbus NE
to 25 miles south of Concordia KS. For a complete depiction of the
watch see the associated watch outline update (WOUS64 KWNS WOU4).
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.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 213...
AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 3 inches. Extreme turbulence and surface wind
gusts to 65 knots. A few cumulonimbi with maximum tops to 550. Mean
storm motion vector 24035.
...Mosier
WW 213 TORNADO IA MN NE SD 171840Z - 180300Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 213
NWS Storm Prediction Center Norman OK
140 PM CDT Sun May 17 2026
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
Northwest Iowa
Far Southwest Minnesota
Northeast Nebraska
Southeast South Dakota
* Effective this Sunday afternoon and evening from 140 PM until
1000 PM CDT.
* Primary threats include...
A few tornadoes likely with a couple intense tornadoes possible
Scattered damaging winds likely with isolated significant gusts
to 85 mph possible
Scattered large hail likely with isolated very large hail events
to 3 inches in diameter possible
SUMMARY...Thunderstorm coverage and intensity is expected to
increase this afternoon along and ahead of a cold front moving into
the Mid Missouri Valley. Strong buoyancy and shear will favor
supercells with any discrete development. These intense supercells
would be capable of all hazards, including very large hail (up to
3"+ in diameter) and strong tornadoes. More linear development is
expected along the front, with strong gusts and line-embedded
possible, particularly across eastern portions of the watch (i.e.
far northeast Nebraska, far southeast South Dakota, northwest Iowa
and southwest Minnesota).
The tornado watch area is approximately along and 70 statute miles
north and south of a line from 40 miles west northwest of Oneill NE
to 35 miles north of Storm Lake IA. For a complete depiction of the
watch see the associated watch outline update (WOUS64 KWNS WOU3).
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 3 inches. Extreme turbulence and surface wind
gusts to 75 knots. A few cumulonimbi with maximum tops to 500. Mean
storm motion vector 24035.
...Mosier
WW 0216 Status Updates
STATUS FOR WATCH 0216 HAS NOT BEEN ISSUED YET
WW 0215 Status Updates
STATUS REPORT ON WW 215
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 N LAA TO
15 SW ITR TO 35 NW ITR TO 35 SE AKO TO 45 ESE AKO TO 10 SSE MCK.
..JEWELL..05/17/26
ATTN...WFO...GLD...
STATUS REPORT FOR WS 215
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
COC017-063-125-180040-
CO
. COLORADO COUNTIES INCLUDED ARE
CHEYENNE KIT CARSON YUMA
KSC023-109-153-181-193-199-180040-
KS
. KANSAS COUNTIES INCLUDED ARE
CHEYENNE LOGAN RAWLINS
SHERMAN THOMAS WALLACE
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.
WW 0214 Status Updates
STATUS REPORT ON WW 214
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 NE RSL TO
30 WNW CNK TO 20 E HSI TO 45 WSW OFK.
..SQUITIERI..05/17/26
ATTN...WFO...OAX...TOP...GID...ICT...
STATUS REPORT FOR WT 214
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
IAC071-085-129-137-145-155-165-180040-
IA
. IOWA COUNTIES INCLUDED ARE
FREMONT HARRISON MILLS
MONTGOMERY PAGE POTTAWATTAMIE
SHELBY
KSC027-029-105-117-123-131-143-149-157-161-167-201-180040-
KS
. KANSAS COUNTIES INCLUDED ARE
CLAY CLOUD LINCOLN
MARSHALL MITCHELL NEMAHA
OTTAWA POTTAWATOMIE REPUBLIC
RILEY RUSSELL WASHINGTON
NEC011-023-025-035-037-053-055-059-067-081-095-097-109-121-125-
127-129-131-133-141-143-147-151-153-155-159-169-177-185-
180040-
WW 0213 Status Updates
STATUS REPORT ON WW 213
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 E BUB TO
30 ESE YKN TO 30 ENE FSD TO 45 NNW OTG.
..SQUITIERI..05/17/26
ATTN...WFO...FSD...OAX...LBF...
STATUS REPORT FOR WT 213
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
IAC021-035-041-059-093-119-133-141-143-149-167-193-180040-
IA
. IOWA COUNTIES INCLUDED ARE
BUENA VISTA CHEROKEE CLAY
DICKINSON IDA LYON
MONONA O'BRIEN OSCEOLA
PLYMOUTH SIOUX WOODBURY
MNC033-063-101-105-133-180040-
MN
. MINNESOTA COUNTIES INCLUDED ARE
COTTONWOOD JACKSON MURRAY
NOBLES ROCK
NEC003-021-039-043-051-119-139-167-173-179-180040-
NE
. NEBRASKA COUNTIES INCLUDED ARE
MD 0758 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR EXTREME EASTERN TEXAS PANHANDLE...NORTHWEST OKLAHOMA INTO SOUTH-CENTRAL KANSAS
Mesoscale Discussion 0758
NWS Storm Prediction Center Norman OK
0519 PM CDT Sun May 17 2026
Areas affected...extreme eastern Texas Panhandle...northwest
Oklahoma into south-central Kansas
Concerning...Severe potential...Watch likely
Valid 172219Z - 180045Z
Probability of Watch Issuance...80 percent
SUMMARY...At least isolated supercells are possible later this
afternoon and into the early evening. The conditional risk of very
large damaging hail is high, along with a risk of a couple
tornadoes. The area is being monitored for initial deep convection.
DISCUSSION...High based convection currently exists within the
low-level lapse rates plume west of the dryline from the TX
Panhandle into far southwest KS where temperatures have reached 100
F. Meanwhile, mid 90s F extend into much of northwest OK, where
little convective inhibition remains.
Low-level moisture is in the process of increasing from the
southeast. GPS PWAT values around 1.25" are moving across central
OK, while values near 1.60" are noted near the Red River. This
suggests higher-quality boundary layer moisture will eventually
spread northwestward into the strongly heated zone from the TX
Panhandle into northwest OK later this afternoon into the early
evening.
Modified 18Z OUN sounding indicates low to mid 90s F temperatures
are needed to remove inhibition. This will become more likely as the
moisture spreads northwestward. Steep midlevel lapse rates over 8.0
C/km along with about 40 kt deep-layer shear oriented west-east
across the dryline suggest supercells with very large hail potential
will be possible. A tornado, even strong, cannot be ruled out with
any longer tracked supercell.
..Jewell/Smith.. 05/17/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...ICT...OUN...DDC...AMA...
LAT...LON 35080050 37289965 37879947 38379918 38419879 38259828
37589777 37099758 36739758 36469772 36229829 35929900
35179961 34860000 34930048 35080050
MOST PROBABLE PEAK TORNADO INTENSITY...100-125 MPH
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...2.75-4.25 IN
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0302 PM CDT Sun May 17 2026
Valid 172000Z - 181200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL PLAINS AND MID MISSOURI VALLEY...
...SUMMARY...
Severe thunderstorms are expected this afternoon into tonight across
parts of the southern/central Plains to the Upper Midwest.
Supercells with very large hail and strong tornadoes are possible
initially this afternoon, before one or more bowing clusters leads
to a greater threat for severe/damaging winds this evening.
...20z Update portions of the northern MO Valley and Midwest...
Earlier elevated convection across southern SD has gradually
strengthened into a broader convective complex ahead of the cold
front this afternoon. Current expectations are for this cluster, and
additional supercells to evolve near the synoptic warm front near
the SD/NE/IA and MN borders this afternoon/evening. Strongly backed
low-level flow will support a tornado risk with a mixed convective
mode before upscale growth into an MCS/bowing cluster this evening.
Thereafter, a significant damaging wind threat with a few embedded
tornadoes may evolve along the warm frontal corridor across northern
IA and southern MN tonight. Damaging wind probabilities have been
increased ahead of this cluster.
Farther south, a CIG2 tornado area was considered across eastern NE
and west-central IA given the presence of STP 4-7 possibly
overlapping with discrete supercells. However, numerous storms are
expected ahead of the cold front with expected interactions casting
uncertainty on the longevity of the more discrete storms.
Regardless, a volatile thermodynamic and kinematic environment (RAP
ESRH 300-400 m2/s2) could support the threat for a higher-end
tornado this evening across southeastern NE and southwestern IA
should supercells remain more discrete.
...Southern OK and North TX...
Modest ascent from a subtropical jet over portions of TX could
support isolated thunderstorm development in the Red River Vicinity
to central TX this evening. A broadly unstable environment with 70s
F surface dewpoints of sufficient bulk shear for supercells could
support some hail or damaging wind risk with any convection able to
develop. Confidence in this scenario remains very low.
...Central High Plains...
Air mass destabilization is ongoing in the post-frontal upslope flow
regime across the central High Plains. Supercells remain likely with
large hail, damaging gusts and a tornado or two. Eventually one or
more clusters may evolve and spread eastward with an increased risk
for damaging gusts tonight. Higher probabilities were shifted
southward slightly to better align with the observed cold frontal
position.
Else where the outlook remains unchanged, see the previous
discussion.
..Lyons.. 05/17/2026
.PREV DISCUSSION... /ISSUED 1129 AM CDT Sun May 17 2026/
...Synopsis...
12Z soundings across the central and southern Plains reveal steep
mid-level lapse rates (8.8 deg C per km at OUN, SGF, and TOP) atop
returning low-level moisture (100 mb mean mixing ratios of 15.4 and
13.1 g/kg at OUN and FWD, respectively). An MCV, from overnight
storms across the Plains, is progressing into northern IL/southern
MN. 12Z DVN sounding sampled a corridor of 50 kt at the base of this
MCV.
Morning surface analysis reveals an intricate surface pattern across
the High Plains/Plains, with multiple lows within the lee troughing
that extends from eastern MT through the central High Plains, a pair
of warm fronts, and a residual outflow boundary across NE. The
deepest surface low is over the far southern CO/KS border vicinity,
with a warm front extending east-northeastward, roughly along the 70
deg F isotherm. A dryline also extends southward from this low into
far west TX. Another low is in place farther north over western NE.
Another warm front, this one along a sharp gradient in low-level
moisture, extends northeastward from this low into far southeast SD
before arcing more eastward across far southern MN and continuing
across from southern WI into central Lower MI. The aforementioned
outflow also extends eastward from this low across central NE.
All of these boundaries will likely influence the severe potential
today, combining with an emerging upper trough and moderate to
strong instability, to support an expansive and complex scenario
today.
...Central Plains into the Upper Midwest...
Expectation is for the northern warm front mentioned in the synopsis
to continue northward throughout the day while as cold front sweeps
southeastward across SD and NE. Thunderstorm development is
anticipated as the cold front interacts with the returning low-level
moisture. Moderate to strong buoyancy (i.e. MLCAPE from 2000 to 3000
J/kg) will support robust thunderstorms from southeast SD through
south-central NE, potentially as far south as central KS. This
activity along the front will become linear quickly with damaging
gusts as the primary risk. Some cell-in-line structures could
support large to very large hail, particularity early in the
convective cycle.
Within this larger area of severe wind and hail potential, two areas
appear to have a greater tornado threat. One is from
northeast/east-central NE into far southeast SD. Here, the influence
of a residual outflow boundary could support more discrete
development ahead of the front. Any discrete development in the warm
sector would likely be supercellular and capable of all hazards,
including very large hail (over 2.5") and a strong tornado. The
other area is where the convective line interacts with the warm
front amid a strengthening low-level jet, likely far northern IA/far
southern MN. Here, increased low-level shear coupled with
augmentation from interaction with the front could result in
significant severe gusts as well as lined-embedded QLCS tornadoes.
...Central High Plains...
Thunderstorm development still appears likely across northeastern CO
this afternoon in a low-level upslope flow regime. This activity
will likely become supercellular and capable of producing large to
very large hail given the presence of steep mid-level lapse rates,
strong deep-layer shear, and moderate instability. Just how far
east/northeast (into central NE) thunderstorms remains strong is a
question of timing. Earlier storms could interact with the front as
it moves through NE, potential leading to persistence or
reintensification. However, later timing would take these storms
into central NE behind the cold front. Steep mid-level lapse rates
in place could still support these storms for a few hours, but the
overall intensity will likely gradually decrease.
...Southern WI into Lower MI...
An MCV is current progressing into northern IL/southern MN. Modest
buoyancy and moderate deep-layer shear will support isolated
elevated thunderstorms capable of small hail and locally strong wind
gusts through early afternoon. This MCV is expected to continue
northeastward into Lower MI, potentially interacting with a warm
front moving north across the region this afternoon. 12Z DVN
sounding sampled enhanced mid-level flow with this MCV, which could
result in enough shear to support organized convection along and
near the warm front later this afternoon/evening. Strong multicells
and an isolated supercell or two could occur, with an attendant risk
for damaging winds, hail, and perhaps a tornado.
...South-Central KS into the eastern TX Panhandle and western OK...
Some guidance continues to show at least isolated high-based
convection developing by late afternoon across parts of
north-central KS southward into the eastern TX Panhandle/western OK.
Any thunderstorms which can be sustained would likely be
supercellular and capable of all severe hazards, including large to
very large hail and tornadoes. Increasing low-level shear after 00Z
supports a conditional risk for a strong tornado.
-- No changes to these areas from the earlier 13Z Outlook --
...Southeast...
On the western periphery of a surface high centered over the western
Atlantic, diurnally maximized thunderstorm development should focus
from the southern Appalachians across GA and the interior/western FL
Peninsula. Even though deep-layer shear will remain weak, a
favorable thermodynamic environment with steepened low-level lapse
rates should support strong to pulse-severe type convection capable
of producing isolated wind damage/downbursts and perhaps marginally
severe hail.
...Central and North Texas/ArkLaTex/Lower Mississippi Valley...
A fairly robust cap is expected to remain across the southern extent
of the warm sector today, with minimal/nebulous large-scale ascent
over the southern Plains. Still, some guidance suggests elevated
thunderstorms may develop through peak afternoon heating across
parts of northeast TX into the ArkLaTex/lower MS Valley in
persistent low-level warm advection regime. If this occurs, then
isolated severe hail and damaging winds would be possible given the
strong MUCAPE forecast.
...Mid-Atlantic...
Mid-level ridging should build over the Mid-Atlantic through the
afternoon, which should tend to suppress most convection. However, a
weak mid-level perturbation noted in water vapor imagery this
morning over OH may support isolated convective development this
afternoon across parts of MD/PA and vicinity. The overall
environment does not appear overly favorable for organized severe
thunderstorms, but gusty winds could occur with any of the stronger
cores that may develop.
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0211 PM CDT Sun May 17 2026
Valid 191200Z - 201200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE GREAT
LAKES TO THE SOUTHERN PLAINS...
...SUMMARY...
Widely scattered severe thunderstorms will be possible along a cold
front extending from the Great Lakes into the Ohio Valley and the
southern Plains.
...Great Lakes and vicinity...
An ejecting midlevel trough over the upper MS Valley early in the
period will begin to phase with the northern stream while moving
eastward over the Great Lakes. An associated surface cyclone will
move across southern ON/QC, as a trailing cold front progresses
southeastward across the OH/middle MS Valleys and into the southern
Plains. Convection will likely be ongoing at the start of the
period along the cold front from northwest TX and OK to the middle
MS Valley and the vicinity of Lake MI. The stronger low-midlevel
flow will be confined to the area closer to the Great Lakes, where
some diurnal destabilization could allow an uptick in threat for
wind damage and isolated large hail.
...Lower OH Valley into the southern Plains...
Farther southwest, flow aloft will be weaker and convection will be
tied to the slowing front and/or convective outflows from D2
convection persisting into D3. Moderate to strong buoyancy (greater
to the west into TX) is expected just ahead of the front, which
combined with the relatively weak wind profiles, will favor
multicell clusters and line segments capable of producing occasional
wind damage and isolated large hail through the afternoon. There
will be some potential for an isolated supercell or two to move off
the Serranias del Burro into TX where large CAPE will coincide with
the cyclonic side of the subtropical jet and at least marginally
sufficient vertical shear. Otherwise, the pattern will transition
overnight to a weak warm advection regime atop the cool air mass,
where elevated storms could produce large hail from northwest TX
into southern OK.
..Thompson.. 05/17/2026
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0226 PM CDT Sun May 17 2026
Valid 181200Z - 191200Z
...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EXTREME
EASTERN NEW MEXICO...EXTREME SOUTHEASTERN COLORADO...FAR
SOUTHWESTERN KANSAS...AND MUCH OF THE TEXAS AND OKLAHOMA
PANHANDLES...
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHWEST AND
SOUTHERN HIGH PLAINS...
The threat of dangerous fire weather conditions is expected to
continue again tomorrow (Monday) over the southern High Plains.
Slight adjustments were made to the outlook areas over the Southwest
and southern High Plains. The Extremely Critical was expanded very
slightly eastward to include additional portions of southwest KS and
much of the remainder of the OK/TX Panhandles. These changes were
again made to tighten the risk gradient near the anticipated
position of the dryline. Although not expected to be a factor
affecting the current northern extent of the drawn risk areas, the
impending cold front passage will impact any suppression efforts
across northern portions of the highlighted area late on Day
2/Monday. The latest forecast guidance suggests that this front will
reach southwest KS around 00Z. The Elevated area was also expanded
to include much of the remainder of the state of NM and slightly
more of south-central CO.
Over California, much of the Sacramento Valley was again added to an
Elevated risk area for Day 2/Monday. Forecast guidance indicates
that north/northeasterly winds sustained at 15-25 mph will overlap
10-20% RH across northern portions of the Central Valley from just
after noon local time through sunset.
..Stearns.. 05/17/2026
.PREV DISCUSSION... /ISSUED 0203 AM CDT Sun May 17 2026/
...Synopsis...
***Dangerous fire weather conditions are expected for parts of the
southern High Plains tomorrow (Monday)***
A pronounced mid-level trough will advance to the central CONUS,
encouraging the deepening of a surface low along the Kansas and
Oklahoma borders, resulting in another day of volatile fire weather
conditions behind a dryline and ahead of a surface cold front over
the southern High Plains. The combination of downslope and gradient
flow in the post-dryline environment will support widespread 20-30
mph sustained southwesterly surface winds amid 5-10 percent RH,
necessitating Critical highlights from New Mexico to the Texas
Panhandle and southwest Kansas areas. Extremely Critical highlights
have also been added across portions of the Texas and Oklahoma
Panhandles into far southwestern Kansas. Here guidance consensus is
strongest in sustained southwesterly surface winds exceeding 30 mph
amid single-digit RH. Given loaded fuels with ERCs exceeding the
95th percentile, any new or rejuvenated fire ignitions may spread at
a life threateningly rapid pace.
By evening, a surface cold front will sweep across the southern High
Plains, approaching from the north. As such, west-southwesterly
surface winds will quickly shift to northerly around 6-9 PM local
time, which may result in a rapid, dangerous change in direction of
forward movement to any ongoing wildfire fronts.
...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
0439 PM CDT Sun May 17 2026
Valid 191200Z - 251200Z
A progressive mid-level synoptic pattern is expected to persist
across the central CONUS through mid-week. The primary mid-level
trough driving current fire weather concerns (on Day 1/Sunday and
Day 2/Monday) will eject northeastward into the Plains, driving a
cold front with precipitation through the central US. Behind the
front will overspread a combination of below normal temperatures and
fairly widespread precipitation across much of the central and
eastern portions of the CONUS as the synoptic flow begins to
stabilize through the end of the work week. This will briefly dampen
the fire weather threat across much of the country on Tuesday and
likely continuing through next weekend. This could support
additional green up in some locations, particularly across the
northern CONUS, that have thus far been struggling to grow
fire-slowing vegetation. However, much longer duration precipitation
and cool conditions would be needed to appreciably improve heavy
dead fuel moisture and resultant ERCs.
...Southwest...
On Day 3/Tuesday and Day 4/Wednesday, lingering moderately strong
mid-level flow overhead as the trough begins to lift northeast will
contribute to additional chances, albeit less certain, for critical
wind/RH over portions of the Southwest. While the footprint may be
slightly different from one day to the other, daytime southwest
winds sustained at 10-20 mph will combine with minimum RHs of
10-20%. Thus, 40% probabilities of critical conditions remain in the
forecast over portions of AZ and NM.
..Stearns.. 05/17/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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