RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Tue Apr 28 10:02:02 UTC 2026.
MD 0590 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR NORTHWEST TEXAS INTO SOUTHWEST/SOUTHERN OKLAHOMA
Mesoscale Discussion 0590
NWS Storm Prediction Center Norman OK
0449 AM CDT Tue Apr 28 2026
Areas affected...northwest Texas into southwest/southern Oklahoma
Concerning...Severe potential...Watch possible
Valid 280949Z - 281245Z
Probability of Watch Issuance...60 percent
SUMMARY...Storms are expected to increase in coverage and intensity
through the morning hours, with isolated damaging hail possible. A
watch may be required.
DISCUSSION...Surface analysis shows a warm front moving northward
into northwest TX and across the Red River, with 68-70 F dewpoints
to the south. Both IR imagery and GPS water vapor sensors indicate a
rapid northward surge of moisture, with PWAT values increasing from
0.55 to over 1.20" in about 2 hours. Already, thunderstorms have
developed 1-2 hours ahead of schedule southeast of LBB, and a
gradual increase has been seen in storm intensity.
Southerly winds just off the surface will raise elevated instability
values north of the warm front over the next several hours. Some
forecast soundings indicate MUCAPE over 4000 J/kg, though effective
value will depend on moisture depth/quality in the elevated
slab/layer. Clearly, the environment will favor hail regardless,
with deep-layer effective shear over 60 kt, along with steep lapse
rates aloft and ample/increasing moisture.
Uncertainty exists as to how far north severe hail cells will
develop, but consensus is at least into southern OK. Significant
hail over 2.00" diameter is quite possible, perhaps larger should
sustained elevated supercells develop as depicted by some models. As
such, a watch will need to be considered this morning.
..Jewell/Gleason.. 04/28/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...FWD...OUN...SJT...LUB...
LAT...LON 33110118 33500114 34600015 35099890 35319756 35049663
34489661 34189678 33759729 33199918 33000083 33110118
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN
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SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1259 AM CDT Tue Apr 28 2026
Valid 281200Z - 291200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
NORTHERN TEXAS INTO THE LOWER MISSISSIPPI VALLEY...
...SUMMARY...
Multiple rounds of strong to severe thunderstorms are likely across
parts Texas into the lower Mississippi and Tennessee Valleys this
afternoon and evening. Very large hail, swaths of damaging wind, and
a few tornadoes are possible.
...Synopsis...
A series of mid-level troughs, embedded within a broader
low-amplitude mid-level flow regime, will traverse the central U.S.
today. A surface low and associated cold front will continue to
progress across the OH Valley toward the East Coast during the day.
However, the approach of another mid-level trough over the Ozark
Valley region will encourage either a weak surface low or surface
trough to develop over central TX. This will stall the southward
progression of the surface cold front given appreciable low-level
warm-air/moisture advection. Seasonally cold air aloft and
accompanying upper support from multiple embedded mid-level
perturbations will overspread the warm-air advection regime,
supporting several rounds of thunderstorms. Given strong vertical
wind shear over the warm sector, severe storms are likely,
especially over portions of the southern Plains toward the TN
Valley.
...Portions of northern TX into the TN Valley...
A complex severe weather scenario is expected across TX into the TN
Valley through the period, with multiple rounds of severe
thunderstorms likely. The first round of storms is currently
initiating over western TX, and may increase in coverage between
12-18Z across central OK into northern TX as a lead mid-level
impulse traverses a WAA regime. 7-8 C/km mid-level lapse rates amid
50+ kts of effective bulk shear will support elevated multicells
capable of producing severe hail. These storms will progress across
the MS Valley through the day. Some guidance indicates that these
storms may evolve into an MCS by afternoon, accompanied by a
damaging gust threat over the Gulf coast states.
Regardless of the evolution of earlier storms, guidance consensus
depicts adequate clearing behind this initial wave over TX into the
Ozark Valley region. Strong surface heating will encourage surface
temperatures to reach 90 F in some locales, amid 70+ F surface
dewpoints. Given 8-9 C/km mid-level lapse rates, MLCAPE should reach
the 2500-4000 J/kg range by mid to late afternoon. By this time, the
primary mid-level trough will overspread the southern Plains,
promoting enough deep-layer ascent for another round of storms to
initiate. Given 50 kts of effective bulk shear and initially
straight hodographs, supercells are expected, accompanied by a
severe hail threat. The most intense supercells may develop over
northern TX and progress eastward, and will be capable of producing
severe hail as large as 3-4 inches in diameter. Given a lingering
low-level jet (supporting elongated hodographs with some low-level
curvature) over the Sabine River Valley, a few dominant/right-moving
supercells may produce a few tornadoes, though the tornado threat
will be conditional on adequate boundary-layer
mixing/destabilization. Later in the afternoon/early evening, severe
hail/isolated tornado producing supercells may merge into an MCS,
accompanied by a severe wind threat across the Lower MS Valley.
...Portions of central into southern TX...
Forcing for ascent will be weak across portions of central into
southwestern TX. Nonetheless, 8-9 C/km mid-level lapse rates will
overspread a well-mixed boundary layer. Tropospheric speed shear
exceeding 40 kts will yield elongated hodographs, so any storm that
can initiate, mature, and sustain itself should be supercellular in
nature, accompanied by a severe hail threat. Any instance of hail
with these storms may include stones exceeding 2 inches in diameter.
Since a second, low-amplitude mid-level impulse will overspread
western and central TX toward the end of the period, isolated
supercell initiation will be possible across portions of central
into southwestern TX late this afternoon into early (12Z) Wednesday
morning.
..Squitieri/Moore.. 04/28/2026
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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1227 AM CDT Tue Apr 28 2026
Valid 291200Z - 301200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS WEDNESDAY
AFTERNOON AND EVENING IN A CORRIDOR ACROSS SOUTHERN TEXAS THROUGH
THE NORTH CENTRAL GULF COAST...AND ACROSS THE ALLEGHENY PLATEAU INTO
MID ATLANTIC...
...SUMMARY...
Widely scattered strong to severe storms may impact a corridor from
south of the Texas Big Bend through the north central Gulf Coast
vicinity Wednesday afternoon into evening, with additional strong
storms posing at least some risk for severe weather across the
Allegheny Plateau into Mid Atlantic.
...Discussion...
Models still indicate that mid-level ridging will build inland
across the Canadian Rockies/Pacific Northwest through this period,
but it appears that attempts at a developing embedded high near the
Pacific Northwest coast will become suppressed by a short wave
impulse within the westerlies approaching the British Columbia
coast. Farther south, a mid-level low merging into a belt of
westerlies emanating from the subtropical eastern Pacific may
accelerate toward southern California/northern Baja coastal areas,
but models continue to substantively vary concerning this motion.
A downstream subtropical high, initially centered over southern
Mexico, may undergo at least some further southwestward suppression,
but it still may maintain considerable influence as far north as
southern Texas through Texas Gulf coast Wednesday through Wednesday
night. At the same time, in higher latitudes, large-scale troughing
encompassing much of north central and northeastern North America is
forecast to continue slowly digging toward the northern/mid Atlantic
Seaboard. A broad embedded cyclonic mid-level circulation may begin
to form near/north of the Great Lakes region.
The confluent mid-level regime across and east of the Rockies will
likely support southeastward development of cool surface ridging
across much of the Great Plains and Mississippi Valley, in the wake
of a southeastward advancing cold front. Models generally suggest
that a modest surface low evolving along this front may migrate
from the lower Ohio Valley northeastward through the lower Great
Lakes region, with a modest secondary surface low forming along a
developing warm front to the east of the Blue Ridge by late
Wednesday afternoon into evening, but there is notable spread within
the guidance concerning this evolution.
...Lower Rio Grande Valley into north central Gulf Coast...
Uncertainties abound concerning the convective potential for this
period. The continuing presence of mid-level ridging and warm
elevated mixed-layer air may be inhibitive to more than isolated
sustained thunderstorm development east of the Rio Grande River, to
the south of Del Rio, through much of Deep South Texas. Across the
upper Texas coastal plain through much of the Gulf Coast states,
conglomerate convective outflow from thunderstorm activity today
through tonight may slow destabilization ahead of the southward
advancing cold front, and there is spread concerning where this
outflow may end up by 12Z Wednesday.
Still, subtle short wave perturbations within moderate to strong
west-northwesterly mid/upper flow, near/north of the periphery of
the subtropical ridging, may provide support for thunderstorm
initiation with boundary-layer destabilization. Guidance suggests
that this may include at least pockets of moderate CAPE, sufficient
for isolated to widely scattered intense convection which could
evolve into supercells and/or small organized clusters with
potential to produce severe hail and wind.
...Allegheny Plateau into Mid Atlantic...
Given the spread among the latest model output concerning the
initial surface frontal low migrating through the Ohio Valley, and
the developing surface troughing/warm front to the east of the Blue
Ridge, substantial uncertainty remains concerning the convective
potential for this period. Remnant convective cloud cover and rain
overspreading the region early in the day may also impede
destabilization. However, with at least weak to moderate
boundary-layer destabilization, strengthening wind fields and
forcing for ascent associated with an approaching mid-level jet
could become conducive to organized severe storm development. This
may initiate west of the Allegheny Mountains, and include potential
for evolving supercell structures, before developing to the east of
the Blue Ridge by late Wednesday afternoon into evening.
..Kerr.. 04/28/2026
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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0227 AM CDT Tue Apr 28 2026
Valid 301200Z - 011200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Probabilities for severe storms Thursday through Thursday night
appear less than 5 percent.
...Discussion...
Models suggest that an elongated area of lower mid-level heights
will continue a slow east-southeastward progression across much of
the upper Mississippi Valley through northern Atlantic Seaboard,
with an embedded cyclonic circulation redeveloping southeastward
through the Great Lakes region. In its wake split westerlies will
remain broadly confluent across and east of the Rockies, as a short
wave perturbation emerges from the subtropical eastern Pacific.
Further suppression of subtropical ridging centered across southern
Mexico appears probable Thursday through Thursday night, but short
wave ridging may persist to the east of the southern Rockies,
downstream of the subtropical perturbation.
Model spread remains sizable concerning the evolution and motion of
the subtropical perturbation, as well as developments within a
branch of westerlies to the north, emanating from the mid-latitude
Pacific. However, to the east of the Rockies, cool surface ridging
is likely to be maintained across much of the Great Plains and
Mississippi Valley into Southeast. While the frontal zone on the
leading edge of this air mass advances away from much of the
Atlantic Seaboard, it is generally forecast to stall across northern
Florida through the northern Gulf or Gulf coast vicinity. More
uncertainty exists, due to model spread, whether it will make
further progress southward through the Texas Big Bend vicinity and
coastal plain, or redevelop northward a bit, north of the coastal
plain and Pecos Valley.
Forcing for ascent associated with lower/mid-tropospheric warm
advection, downstream of the approaching subtropical perturbation,
may contribute to a corridor of increasing thunderstorm development
above the stable surface-based air across parts of the Permian Basin
and Texas South Plains through much of central Texas by late
Thursday night. However, it remains unclear if elevated
destabilization will become supportive of a risk for severe hail,
before convection becomes increasingly widespread.
Otherwise, the front might provide a general focus for widely
scattered thunderstorm activity near the Gulf coast vicinity, while
destabilization beneath cool mid-level air across the Great Basin
into southern Rockies supports scattered, mostly diurnal
thunderstorm activity.
..Kerr.. 04/28/2026
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Day 4-8 Outlook
Day 4-8 Convective Outlook RESENT 1
NWS Storm Prediction Center Norman OK
0423 AM CDT Tue Apr 28 2026
Valid 011200Z - 061200Z
...DISCUSSION...
Medium-range guidance indicates that the evolving split flow may
maintain a broadly confluent mid-level regime across and east of the
Rockies through this period. While a broad area of lower mid-level
heights remains centered across the Ontario/Quebec and Upper Midwest
through Northeast, it appears that a more prominent blocking
ridge/high may evolve upstream near the British Columbia/Pacific
Northwest coast by late this coming weekend into early next week. A
developing low to its southeast may slowly progress inland across
California into the Southwest, with downstream mid-level ridging
building across the Rockies.
There is considerable model spread concerning embedded short wave
developments, but it appears that potential for stronger convection
will remain generally low for the time of year and confined to parts
of the southern tier of the U.S., perhaps including parts of the San
Joaquin Valley, as well as along a lingering frontal zone near or
just south of the Gulf into southern Atlantic coastal plain. Due to
a combination of low predictability and low severe weather
potential, severe weather probabilities are being maintained at less
than 15 percent through this period.
Read more
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1229 AM CDT Tue Apr 28 2026
Valid 281200Z - 291200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN NEW MEXICO AND
WESTERN TEXAS...
...Synopsis...
As a low pressure system off the West Coast slowly approaches Baja
CA, a mid/upper shortwave trough over the Southwest will traverse
the High Plains encouraging strong westerly mid-level flow. Fire
weather conditions will continue for portions of western NM into the
southern Plains as a result of downslope warming and boundary layer
mixing. A deepening surface low will pass over the Great Lakes
region into southern Ontario, assisting in the breakdown of upper
ridging along the Eastern Seaboard. Increasing low-level southerly
flow ahead of an incoming trough and associated cold front will
allow for fire weather concerns to emerge in Upstate NY and western
VT amid a very dry airmass.
...Southern Plains...
Critical fire weather conditions are expected to continue this
afternoon where a dry airmass and strong winds overlap a region of
receptive fuels. Widespread west to southwest winds of 15-20 mph
coupled with RH falling to 10-20 percent atop a dry fuelscape will
increase fire spread potential for any new and/or ongoing wildfires.
More intense wind belts of 20-25 mph aligning with RH reductions
close to 10 percent yield Critical fire weather conditions across
east-central and southeastern NM into adjacent portions of TX.
...Upstate New York and Western Vermont...
As surface pressure gradients tighten surrounding a surface low
positioned over central/eastern Ontario, southerly winds are
expected to reach 10-15 mph with localized/terrain enhanced 20 mph
corridors likely. Mid-upper level cloud cover will increase this
morning through the afternoon hours, potentially limiting deeper
mixing. However, RH of 25-35 percent (locally near 20 percent) are
still expected by early afternoon. These dry and breezy conditions
will align amid dry fuels to promote an Elevated fire weather threat
across upstate NY and western VT.
..Elizalde-Garcia.. 04/28/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1231 AM CDT Tue Apr 28 2026
Valid 291200Z - 301200Z
...Synopsis...
A mid/upper level shortwave trough will traverse the Midwest into
the Ohio Valley as an attendant surface low approaches the
Mid-Atlantic. A trailing cold front will progress east of the
Appalachians extending into the Southeast by Wednesday afternoon.
Dry westerly flow south of the advancing cold front is expected to
increase fire weather concerns for portions of southern GA and
northern FL where fuels remain dry. Enhanced mid-level westerly flow
ahead of an approaching Pacific trough will bolster a continued
downslope regime across the Southwest. With preceding days of
fire-effective weather conditions and receptive fuels, fire weather
concerns will persist over central NM to far eastern AZ on
Wednesday.
...Southwest...
Persistent westerly mid-level flow and developing lee-surface
troughing will promote dry and breezy conditions across eastern AZ
into central NM. While winds are fairly marginal compared to
previous days, widespread westerly winds of 15-20 mph and RH of less
than 15 percent amid dry fuels will support Elevated fire weather
conditions on Wednesday afternoon.
...Southern Georgia and northern Florida...
Beneath the upper level trough, a deepening surface low over the
Mid-Atlantic will enhance southwest to westerly surface winds across
much of the Southeast. An Elevated fire weather threat exists where
delayed Gulf moisture return amid an existing dry boundary layer is
expected to support minimum RH reductions of 25-35 percent (locally
less than 25 percent) across portions of southern GA into northern
FL by Wednesday afternoon. However, precipitation appears likely
along a southward progressing cold front through central GA. Fire
weather highlights may be adjusted in future outlooks as forecast
guidance aligns in the location/extent of the cold front and
rainfall amounts.
..Elizalde-Garcia.. 04/28/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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