WW 11 SEVERE TSTM AR IL IN KY MO 042035Z - 050300Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 11
NWS Storm Prediction Center Norman OK
235 PM CST Wed Mar 4 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Northern Arkansas
Southern Illinois
Southwest Indiana
Western Kentucky
Southern Missouri
* Effective this Wednesday afternoon and evening from 235 PM
until 900 PM CST.
* 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...Storms are expected to further develop and intensify
regionally as additional destabilization occurs. This will include
clusters and a few supercells with hail and wind as the primary
hazards, although some tornado potential will exist.
The severe thunderstorm watch area is approximately along and 45
statute miles north and south of a line from 30 miles south
southwest of Harrison AR to 10 miles east northeast of Evansville
IN. 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.
&&
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 450. Mean storm motion vector
26030.
...Guyer
WW 0011 Status Updates
STATUS FOR WATCH 0011 HAS NOT BEEN ISSUED YET
MD 0132 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF THE OZARKS INTO THE LOWER OHIO VALLEY
Mesoscale Discussion 0132
NWS Storm Prediction Center Norman OK
0128 PM CST Wed Mar 04 2026
Areas affected...Portions of the Ozarks into the lower Ohio Valley
Concerning...Severe potential...Watch possible
Valid 041928Z - 042200Z
Probability of Watch Issuance...40 percent
SUMMARY...Portions of the Ozarks into the lower Ohio Valley are
being monitored for an increase in severe thunderstorm potential
this afternoon. Timing on any potential watch remains uncertain.
DISCUSSION...Along the southeastern periphery of a cold front
extending from south-central MO into eastern OK, clusters of
elevated/disorganized thunderstorms continue this afternoon. This
activity is being aided by DCVA preceding a midlevel trough
traversing the central Plains and weak low-level warm advection atop
the frontal surface/large-scale cold pool. Along the eastern edge of
this convection, modest diurnal heating (beneath anvil debris) and
lower/middle 60s dewpoints streaming northward amid steepened
midlevel lapse rates are contributing to around 1000-1500 J/kg
MLCAPE. There is some potential for the ongoing convection, as well
as new development along its fringes, to intensify as it impinges on
this increasing buoyancy.
Around 40 to 50 kt of effective shear, with some increasing
low-level hodograph curvature (around 150-200 m2/s2 effective SRH),
would favor organized clusters and supercell structures. However,
this is highly dependent on storms maintaining residence time in the
warm sector, and deep-layer flow/shear oriented parallel to the
composite outflow/front limits confidence in this scenario to an
extent. Nevertheless, any storms that can evolve into the warm
sector would pose a risk of damaging winds, large hail, and possibly
a tornado or two. Timing of any potential watch remains uncertain,
and convective/environmental trends are being monitored.
..Weinman/Guyer.. 03/04/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...IND...PAH...ILX...MEG...LSX...LZK...SGF...
LAT...LON 36049098 35709187 35559260 35619302 35969318 36319311
37079162 37799045 38288969 38538903 38618830 38408750
37908715 37468727 37108776 36758845 36049098
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
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1026 AM CST Wed Mar 04 2026
Valid 041630Z - 051200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTH
TEXAS/EASTERN OKLAHOMA TO OZARKS AND LOWER OHIO VALLEY...
...SUMMARY...
Isolated to scattered severe thunderstorms are expected through
tonight from north-central Texas and eastern Oklahoma to the Ozarks
and Lower Ohio Valley. Large hail, localized wind damage, and a
tornado or two are possible.
...Southern Plains to the Ozarks and Lower Ohio Valley...
Well in advance of an amplifying trough over the Great Basin, a
low-amplitude southern-stream shortwave trough over the
south-central High Plains will continue east-northeastward over the
Lower Missouri Valley through tonight. A base-embedded modestly
increasing belt of southwesterly mid-level flow (50+ kt) will
maximize from northeast Oklahoma/southeast Kansas across the Ozarks,
in general proximity to a weak surface low/frontal zone across the
region where deep-layer/low-level shear are expected to be
maximized.
South of the front, southerly low-level flow will support dewpoints
climbing into generally the low to mid 60s F. While cloud cover may
remain semi-prevalent across the warm sector, this increasing
moisture beneath steep mid-level lapse rates amid filtered daytime
heating should support MLCAPE values generally around 1000-1500 J/kg
in a narrow corridor along/ahead of the front. Locally greater
instability should develop across north-central into central Texas
where stronger daytime heating is expected, although
deep-layer/low-level shear will be notably weaker, while still
sufficient for relatively isolated severe storms.
Across most of the Slight Risk area, effective bulk shear of 35-50
kt will easily support organized convection regionally, although
convective mode may tend to be somewhat messy given broad ascent
within the modest low-level warm advection regime near the surface
front. Additionally, ongoing mostly elevated convection this morning
across northeast Oklahoma into southern Missouri and southern
Illinois may hamper stronger heating and limit destabilization
downstream, with outflow/existing convection contributing to modal
complexity later today.
Even with these potential limitations, a broad area of isolated to
scattered severe thunderstorm potential exists through tonight. An
isolated and/or occasional hail threat may persist with ongoing
elevated convection from southern Missouri into southern
Indiana/northern Kentucky. Surface-based thunderstorm development
should otherwise become more probable across the Ozarks into
mid/late afternoon closer to the surface front/surface low and
modifying outflow. A mix of supercells and clusters will pose a risk
for large hail. Damaging winds will also be possible where steepened
low-level lapse rates can develop with daytime heating. Although
low-level flow is not forecast to become overly strong, there should
be sufficient 0-1 km SRH to support some threat for a couple of
tornadoes with any sustained supercells/clusters, particularly
across southern Missouri and northern Arkansas.
..Guyer/Wendt.. 03/04/2026
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0112 PM CST Wed Mar 04 2026
Valid 042000Z - 051200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTH
TEXAS/EASTERN OKLAHOMA TO OZARKS AND LOWER OHIO VALLEY...
...SUMMARY...
Isolated to scattered severe thunderstorms are expected through
tonight from north-central Texas and eastern Oklahoma to the Ozarks
and Lower Ohio Valley. Large hail, localized wind damage, and a
tornado or two are possible.
...20z Update...
Only minor adjustments were made to remove the Marginal Risk across
a small portion of eastern KS/central MS/central IN where morning
convection has overturned the environment. Otherwise, the Slight
Risk across from north Texas to the Ozarks and Lower Ohio River
Valley continues. See previous discussion below for more
information.
..Thornton.. 03/04/2026
.PREV DISCUSSION... /ISSUED 1026 AM CST Wed Mar 04 2026/
...Southern Plains to the Ozarks and Lower Ohio Valley...
Well in advance of an amplifying trough over the Great Basin, a
low-amplitude southern-stream shortwave trough over the
south-central High Plains will continue east-northeastward over the
Lower Missouri Valley through tonight. A base-embedded modestly
increasing belt of southwesterly mid-level flow (50+ kt) will
maximize from northeast Oklahoma/southeast Kansas across the Ozarks,
in general proximity to a weak surface low/frontal zone across the
region where deep-layer/low-level shear are expected to be
maximized.
South of the front, southerly low-level flow will support dewpoints
climbing into generally the low to mid 60s F. While cloud cover may
remain semi-prevalent across the warm sector, this increasing
moisture beneath steep mid-level lapse rates amid filtered daytime
heating should support MLCAPE values generally around 1000-1500 J/kg
in a narrow corridor along/ahead of the front. Locally greater
instability should develop across north-central into central Texas
where stronger daytime heating is expected, although
deep-layer/low-level shear will be notably weaker, while still
sufficient for relatively isolated severe storms.
Across most of the Slight Risk area, effective bulk shear of 35-50
kt will easily support organized convection regionally, although
convective mode may tend to be somewhat messy given broad ascent
within the modest low-level warm advection regime near the surface
front. Additionally, ongoing mostly elevated convection this morning
across northeast Oklahoma into southern Missouri and southern
Illinois may hamper stronger heating and limit destabilization
downstream, with outflow/existing convection contributing to modal
complexity later today.
Even with these potential limitations, a broad area of isolated to
scattered severe thunderstorm potential exists through tonight. An
isolated and/or occasional hail threat may persist with ongoing
elevated convection from southern Missouri into southern
Indiana/northern Kentucky. Surface-based thunderstorm development
should otherwise become more probable across the Ozarks into
mid/late afternoon closer to the surface front/surface low and
modifying outflow. A mix of supercells and clusters will pose a risk
for large hail. Damaging winds will also be possible where steepened
low-level lapse rates can develop with daytime heating. Although
low-level flow is not forecast to become overly strong, there should
be sufficient 0-1 km SRH to support some threat for a couple of
tornadoes with any sustained supercells/clusters, particularly
across southern Missouri and northern Arkansas.
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
1135 AM CST Wed Mar 04 2026
Valid 051200Z - 061200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM NORTHWEST
TEXAS TO SOUTHERN KANSAS...
CORRECTED FOR HEADLINE
...SUMMARY...
Scattered severe storms may develop on Thursday evening and persist
into early morning Friday from northwest Texas to southern Kansas. A
few tornadoes, damaging winds, and large hail could occur.
...Synopsis...
A low-amplitude shortwave trough will quickly progress from the
Mid-MS Valley to the Northeast. A broad positive-tilt upper trough
will shift more slowly eastward across the West, reaching the
northern High Plains to Four Corners by early Friday. Downstream lee
cyclogenesis will occur over eastern CO through Thursday afternoon.
A warm front will arc southeast and eventually east from this
cyclone. A separate front will be oriented to the northeast and
north, accelerating southeast over the northern Great Plains
Thursday night. The dryline should only mix slightly east of eastern
NM into far western parts of TX.
...Southern to central Great Plains...
Deepening lee cyclogenesis over eastern CO through the day will
yield increasing low-level moisture return beneath a pronounced EML
from TX to KS. Initial severe-storm concern will develop in the late
afternoon to early evening in the TX Panhandle/northwest TX vicinity
and adjacent western OK. Guidance differs markedly with the degree
of thunderstorm development along the surface warm front as it
advances north. The HRRR/RRFS and MPAS runs are much more aggressive
compared to the NAM-Nest and NSSL-ARW cores with sustained storms.
Differential insolation/boundary-layer heating across the front and
weak mid-level height falls may be adequate for storms ahead of the
effective front/dryline intersection in the western TX Panhandle.
Should sustained development occur, a strengthening nocturnal
low-level jet will maintain an influx of low 60s surface dew points
and surface-based instability into Thursday night.
The initial setup would favor discrete supercells capable of large
hail and at least a couple tornadoes amid a supercell wind profile
and steep mid-level lapse rates. It is plausible that a
longer-track/strong supercell or two could become established to the
northeast through the evening into the early overnight in parts of
western to north-central OK. However, upscale growth into a linear
cluster with embedded supercells seems more probable into the
overnight, capable of producing all hazards. But with some weakening
of near-surface lapse rates anticipated, confidence is low on the
degree of significant severe potential with northeastward extent.
Elevated thunderstorms appear likely to develop farther north in the
southwest/central NE vicinity and in a broader swath across the
Mid-MO Valley overnight. Isolated severe hail and strong gusts could
briefly accompany the more robust storms.
..Grams.. 03/04/2026
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0126 PM CST Wed Mar 04 2026
Valid 061200Z - 071200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN
KS/OK TO WESTERN MO...
...SUMMARY...
Scattered severe thunderstorms are expected from late afternoon
Friday through Friday night from portions of the central/southern
Great Plains to the Midwest. The most probable corridor for
tornadoes, damaging winds, and large hail is across eastern portions
of Kansas and Oklahoma to western Missouri.
...Synopsis...
Broad upper trough over the West should split into two distinct
impulses by Friday night. Leading shortwave trough should eject from
the Four Corners across the central Great Plains to the Upper
Mississippi Valley, while a backside cutoff low evolves over the
Lower CO Valley. Lead cyclone should track from western KS vicinity
across IA to the central Great Lakes. The dryline should mix towards
central OK/TX through late afternoon. A surface cold front will
accelerate southeastward across the central/southern Great Plains on
the backside of the lead cyclone.
...Central/southern Great Plains into the Midwest...
Most appreciable change this outlook has been to flatten the
previously tight gradient to severe probabilities over the Great
Plains. The splitting of the broad western trough and positive-tilt
of the leading shortwave impulse suggests that surface features on
Friday afternoon should lag westward compared to the typically
overmixed GFS. Initial storm development should occur across central
KS near the triple-point mesolow by mid to late afternoon. Expanding
convective coverage is anticipated to the northeast into IA/MO and
south into at least northern OK. Available D3 CAM guidance is much
less robust than parameterized models with the degree of convective
development through early evening towards the Red River and
southward into central TX. With near-neutral mid-level height falls,
it is plausible that convection south of the latitudinally compact
mid-level jetlet will remain isolated. This lowers confidence in the
southern extent of highlighted level 3-ENH risk across most of OK.
Across eastern KS, northern OK, and western Missouri, initial
supercells will probably grow upscale into a broader QLCS during the
evening, with semi-discrete activity favored along the southern
flank. Strengthening 850-700 mb southwesterlies suggest damaging
wind and QLCS tornado potential could persist across the Mid-MS
Valley towards the Lake MI vicinity overnight in a weak MLCAPE/high
shear environment. Available CAM guidance does indicate a general
alignment of QLCS with the deep-layer shear vector, suggesting of a
sporadic severe threat mainly where embedded bowing segments/surges
can develop.
Farther south, storm development will become increasingly probable
as the accelerating cold front overtakes and merges with the front
on Friday night. Outside of frontal convergence and low-level warm
advection atop the undercutting front in western TX, large-scale
ascent should remain nebulous. Large hail may accompany initial
updrafts, with severe wind/tornado potential nocturnally limited.
..Grams.. 03/04/2026
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0151 PM CST Wed Mar 04 2026
Valid 051200Z - 061200Z
...CRITICAL FIRE WEATHER AREA FOR EASTERN/CENTRAL NEW
MEXICO...SOUTHEAST COLORADO...AND THE EXTREME WESTERN OKLAHOMA
PANHANDLE...
The latest forecast guidance has slightly slowed the area of maximum
winds associated with the upper level trough transiting the
central/southern Rockies on Day 2/Thursday. Additionally, in part
due to the timing and curvature of the jet maximum, there is some
uncertainty as to how far east the dryline will progress later in
the day. Meanwhile, the aforementioned elevated to critical
conditions will be ongoing for several hours across a good portion
of central to northeastern New Mexico from noon to sunset local
time. A subtle westward movement was necessitated over the southern
extent of Critical area due to this trend in the latest guidance.
Additionally, the Elevated was expanded over portions of the Trans
Pecos to account for forecast guidance trending toward slightly
lower relative humidity in that area. With additional information on
fuels conditions, also added in portions of eastern central Colorado
and extreme southeastern Arizona.
Consideration was given to a potential dry thunderstorm threat
primarily in the vicinity of the Texas and Oklahoma Panhandles.
Limiting factors precluding any areas include the uncertainty of the
dryline placement and progression, the expected cloud cover over the
region, and the propensity for increasing coverage of strong storms.
..Stearns/Nauslar.. 03/04/2026
.PREV DISCUSSION... /ISSUED 0202 AM CST Wed Mar 04 2026/
...Synopsis...
A deepening upper-level trough will track southeastward over the
Intermountain West and Four Corners D2/Thursday, with an associated
lee surface cyclone developing on the central High Plains through
the day. The surface cyclone will shift southeastward through the
period, with a sharpening, trailing dryline across the
southern/central High Plains. Strong sustained southwesterly surface
winds and very low RH behind this dryline will support widespread
elevated to critical fire weather conditions across the
southern/central High Plains.
...Portions of eastern New Mexico and southeastern Colorado...
Dry, southwesterly downslope flow will increase on D2/Thursday
behind a sharpening dryline across the central/southern High Plains.
Critical fire weather conditions are expected across eastern New
Mexico into southeastern Colorado where the best overlap of stronger
sustained surface winds (20-25 mph), low relative humidities
(5-15%), and receptive fuels is expected. Stronger 700 mb winds
coupled with a deep, well-mixed boundary layer will also support
sporadic wind gusts of 35-45 mph along this corridor. Elsewhere
across the central/southern High Plains, sustained southwesterly
surface winds of 15-20 mph and minimum RH of 15-20% will support
elevated fire weather concerns across much of New Mexico, southeast
Colorado, far west Texas, the Oklahoma Panhandle, and southwestern
Kansas. The eastern extent of elevated/critical fire weather
conditions will depend on the dryline location, while the western
extent is limited by less receptive fuels.
The dryline will be a focus for D2/Thursday late afternoon and
evening thunderstorm development, with the potential for a narrow
corridor of dry thunderstorms from the Caprock into the
Texas/Oklahoma Panhandles and southwest Kansas. Given lingering
uncertainty regarding dryline placement/movement and the potential
for precipitation from developing convection, isolated dry
thunderstorm highlights have been withheld at this time.
...Please see www.spc.noaa.gov/fire for graphic product...
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