RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Wed Apr 29 09:02:02 UTC 2026.
No Mesoscale Discussions are in effect as of Wed Apr 29 09:02:02 UTC 2026.
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1153 PM CDT Tue Apr 28 2026
Valid 291200Z - 301200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF TEXAS AND THE GULF COAST STATES INTO SOUTHERN GEORGIA AND SOUTH
CAROLINAS...AND ACROSS THE CENTRAL APPALACHIANS/SOUTHERN
MID-ATLANTIC...
...SUMMARY...
Widely scattered strong to severe storms may impact a corridor from
south of the Texas Big Bend into the Gulf coast states and southern
Georgia/South Carolina Wednesday afternoon into evening. Additional
strong storms are expected across the central Appalachians and
southern Mid-Atlantic.
...Synopsis...
An upper trough will pivot across the Great Lakes and Midwest today.
Within southern stream flow, a weak shortwave impulse will migrate
through westerly flow aloft from Texas to the GA/SC coast. This will
result in enhanced westerly flow across the southern U.S. and the
Midwest to the Mid-Atlantic. At the surface, a cold front is
forecast to extend from northern IN southwestward into central TX
this morning. This front will develop southward across TX and
southeastward across the Lower MS Valley and Southeast through the
period. The northern extent of the front will shift east across the
Midwest to the Mid-Atlantic. This surface boundary will be a focus
for strong to severe thunderstorm development during the
afternoon/evening.
...TX to GA/SC Coast...
A moist airmass will be in place ahead of the surface front,
particularly across TX where dewpoints in the 70s are common.
Heating into the 80s and 90 of this very moist airmass will result
in a corridor of moderate to strong MLCAPE. The surface boundary
will be the main forcing mechanism for convection across TX and
storm coverage may remain isolated. Further east into the Lower MS
Valley/Southeast, a shortwave impulse will provide modest forcing
for ascent in addition to the southeast sagging cold front.
Isolated supercells across central TX will pose a risk for large
hail, with some potential for 2+ inch hail. Uncertainty concerning
storm coverage and capping across TX precludes an upgrade to Sight
risk at this time. Additional storms are expected to develop closer
to the Sabine Valley and Lower MS Valley this afternoon. Initial
thunderstorm clusters may congeal into one or more linear segment
and move across MS/AL/GA during the late afternoon into evening
hours. Hail and strong wind gusts will be possible with this
activity.
...Central Appalachians/Mid-Atlantic vicinity...
An upper shortwave trough emanating from the Great Lakes/Midwest
upper trough will overspread the region during the afternoon/evening
in tandem with the eastward advancing cold front. Modest boundary
layer moisture is forecast across the region, with dewpoints
generally in the 50s to near 60 F. Modest heating will result in
weak destabilization (generally 500-750 J/kg or less). Despite weak
instability, supercell wind profiles are evident in forecast
soundings. This should aid in at least transient organization of
stronger updrafts with a wind and hail risk. While instability and
moisture will be marginal, 0-1 SRH will approach 150 m2/s2 in
proximity to a weak surface low and a brief tornado could also
occur.
..Leitman/Moore.. 04/29/2026
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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1152 PM CDT Tue Apr 28 2026
Valid 301200Z - 011200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS LATE THURSDAY
AFTERNOON AND EVENING ACROSS PARTS OF THE RIO GRANDE NEAR THE TEXAS
BIG BEND...
...SUMMARY...
A couple of strong storms may impact the Rio Grande River vicinity
near the Texas Big Bend late Thursday afternoon and evening, perhaps
accompanied by at least some risk for severe hail.
...Discussion...
It still appears 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
likely will remain confluent across and east of the Rockies, as a
short wave perturbation emerges from the subtropical eastern
Pacific.
There appears a much better consensus within latest model output
concerning the inland progression of this perturbation, which is now
generally forecast to accelerate across northern Mexico and adjacent
portions of the U.S. Southwest, toward the Texas Big Bend vicinity
Thursday through Thursday night. Downstream short wave ridging is
forecast to gradually shift east of the southern Rockies, across the
southern Great Plains through Gulf Coast, while subtropical ridging
centered across southern Mexico undergoes further suppression.
In lower levels, to the east of the Rockies, cool surface ridging
will be maintained across much of the Great Plains and
Mississippi Valley into Southeast. Most guidance now indicates that
the frontal zone on the leading edge of this air mass will make
slow, but steady, southward progress into and across the Texas Big
Bend and Hill Country, immediate upper Texas/Louisiana coastal
vicinity, and northern Florida.
Forcing for ascent associated with lower/mid-tropospheric warm
advection, downstream of the approaching subtropical perturbation,
may contribute to multiple rounds of 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. Based on latest model output, including Rapid
Refresh and NAM forecast soundings, thermodynamic profiles seem
unlikely to support severe hail. One exception might develop within
moist upslope flow into a more strongly heated environment across
the higher terrain near and south of the Texas Big Bend. Beneath
moderate to strong mid-level flow, the initiation of a couple of
supercells appears possible. However, this activity is expected to
weaken as it acquires less unstable updraft inflow to the east of
the higher terrain.
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.. 04/29/2026
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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Wed Apr 29 2026
Valid 011200Z - 021200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FRIDAY AFTERNOON
INTO FRIDAY NIGHT ACROSS PARTS OF MIDDLE TEXAS COASTAL
AREAS...SOUTHEASTERN LOUISIANA...THE FLORIDA BIG BEND VICINITY AND
ADJACENT PORTIONS OF SOUTHWESTERN GEORGIA...
...SUMMARY...
Isolated severe thunderstorm development is possible across middle
Texas coastal areas, parts of southeastern Louisiana and the Florida
Big Bend region Friday afternoon through Friday night.
...Discussion...
Latest model output suggests that there will be substantive
amplification within the split westerlies emanating from the
mid-latitude Pacific during this period, with ridging building to
the west of 140W longitude into the higher latitudes of western
Canada, and on a larger-scale eastward across the Canadian Prairies
and northern U.S. Rockies. Within this ridging, a modest mid-level
trough and embedded low are forecast to slowly dig to the west of
the U.S. Pacific coast, while broad upper ridging gradually builds
across the subtropical eastern Pacific.
Downstream, a confluent mid-level regime will be maintained across
and east of the Rockies, enhanced across the Great Plains into
middle Mississippi Valley, in the wake of short wave troughing
forecast to dig to the southwest of an elongated area of lower
heights slowly shifting eastward through the Ontario/Quebec/Great
Lakes and Northeast vicinity.
A short wave perturbation reaching the Texas Big Bend vicinity by
12Z Friday is likely to undergo shearing as it progresses through
the confluence to the south of the digging trough. However, as a
reinforcing cool surge noses southward to the lee of the southern
Rockies, across and south/southeast of the Texas Big Bend, guidance
suggests a notable lingering impulse may support a developing wave
along a stalled frontal zone, across middle Texas coastal areas
through the eastern Gulf coast vicinity Friday afternoon through
Friday night.
...Middle Texas coastal plain through Florida Big Bend region...
Large-scale forcing for ascent aided by warm advection along and to
the cool side of the front may support a swath of mostly weak
thunderstorm activity across much of the Gulf into southern Atlantic
coast during this period. Among other model output, forecast
soundings from the NAM and RRFS indicate thermodynamic profiles with
little potential for severe hail and/or wind. One exception may be
across middle Texas coastal areas, where loaded gun type soundings,
probably based above a stable surface-based layer, may become
conducive to supercell development in the presence of strong shear,
as mid-level forcing for ascent overspreads the region by late
afternoon.
Late Friday evening across southeastern-most parishes of Louisiana,
through the Florida Big Bend region by 12Z Saturday, forecast
soundings suggest modest boundary-layer destabilization is possible
in a pre-frontal corridor coincident with strengthening deep-layer
shear and enlarging, clockwise-curved low-level hodographs. It is
possible that this will become supportive of supercells, accompanied
by the risk for a tornado or two, in addition to large hail and
localized damaging wind gusts.
..Kerr.. 04/29/2026
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Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CDT Wed Apr 29 2026
Valid 021200Z - 071200Z
...DISCUSSION...
Latest medium-range guidance, in particular the ECENS and GEFS,
generally maintains forecast trends of prior runs concerning the
evolution of the large-scale features within the prevailing split
flow through this weekend into early next week. It appears that at
least a transient blocking high may evolve within amplified ridging
offshore of the British Columbia and adjacent Pacific Northwest
coast. To its south-southeast a notable mid-level low is forecast
to evolve within initial troughing slowly digging toward the U.S.
Pacific coast, with the low bottoming out offshore of the central/
southern California coast by early next week.
Downstream, it appears that a broad area of lower mid-level heights
will be maintained, with lowest heights perhaps reforming
west-northwestward from southwestern Quebec toward southern Hudson
Bay/northwestern Ontario, contributing to the maintenance of a
confluent regime across and east of the Rockies.
Shorter wavelength developments within this pattern remain more
uncertain, particularly by the early to middle portion of next week,
when it appears that the offshore low will begin to progress inland
across California and the southern Sierra Nevada. Depending on the
timing of the inland progressing mid-level cold core with respect to
diurnal heating, this could be accompanied by relatively minor
severe weather potential across parts of the San Joaquin Valley next
Monday or Tuesday.
Downstream, southerly moist return flow into at least the southern
through central Great Plains, associated with deepening lee surface
troughing, may contribute to destabilization beneath building
mid-level ridging across and east of the southern Rockies. This
might be accompanied by increasing potential for at least widely
scattered strong to severe thunderstorm development on Tuesday.
Guidance suggests potential for more widespread organized severe
thunderstorm development could increase by Wednesday, but much will
depend on short wave developments which become rather uncertain by
this time.
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0104 AM CDT Wed Apr 29 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 this 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 this
afternoon.
...Southwest...
Upper-level cloud cover is currently increasing across much of the
Southwest and southern Plains early this morning owing to a
subtropical jet advecting moisture aloft. This will likely inhibit
RH recoveries west of the NM central mountain chain, preconditioning
an already dry fuel environment. A 50-60 kt mid-level jet at the
base of an embedded, low-amplitude shortwave within broader
west-southwest flow will evolve across the Southwest and southern
Plains today, promoting continued dry and breezy conditions.
Westerly winds of 15-20 mph and RH of less than 15 percent amid dry
fuels will support an Elevated fire weather threat for portions of
eastern AZ into central NM/West TX and the San Luis Valley. Locally
critical fire weather conditions may emerge mainly in the leeward
slopes of the more prominent mountain ranges in southern NM with
sustained winds of 20-25 mph amid 10 percent RH.
...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 as minimal Gulf moisture influence will
overlap a dry and drought stressed landscape. West winds of around
10 mph and RH of 25-35 percent (locally less than 25 percent) are
expected to promote an Elevated fire weather threat across portions
of southern GA into northern FL this afternoon. Early morning
thunderstorms are currently moving across central AL into far
western GA, but are expected to diminish as they approach the
Elevated risk area. However, if precipitation persists farther
southeast than anticipated, fire weather highlights will be adjusted
in the 17z outlook.
..Elizalde-Garcia.. 04/29/2026
...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
0105 AM CDT Wed Apr 29 2026
Valid 301200Z - 011200Z
...Synopsis...
A mid/upper-level Pacific low will move onshore the Baja Peninsula
and transition into an eastward projecting shortwave as a westerly
50-70 kt jet emerges downstream across central TX into the Southeast
on Thursday. Ample Pacific moisture transport will encourage
widespread wetting rains and a reduced fire weather threat across
much of the central and southern High Plains. Broad upper troughing
is forecast to take residence across the Northeast as a closed
upper-level low persists over southern Ontario. A southward
progressing weak cold front will eventually stall over southern GA
and northern FL on Thursday afternoon, bringing increased
precipitation chances to where extensive drought and receptive fuels
remain. However, ahead of the front, high pressure will promote a
warm and dry airmass over Central FL where fire weather concerns
reemerge amid a very dry fuelscape.
...Florida Peninsula...
Ahead of a stalled frontal boundary near the FL-GA line, surface
high pressure will maintain warm and dry conditions for much of the
FL Peninsula on Thursday afternoon. An Elevated fire weather threat
is expected where westerly winds of up to 10 mph will partially
overlap a region of 30-35 percent RH amid receptive fuels and a
drought-ridden environment. Near the frontal boundary, increasing
mid-level moisture along with afternoon heating and resultant
instability may support isolated showers and thunderstorms.
Lightning ignitions are possible in areas that do not see sufficient
rainfall, and resultant gusty/erratic outflow winds from
thunderstorms could further exacerbate any new/ongoing fires.
..Elizalde-Garcia.. 04/29/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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