RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Sat Apr 18 09:55:01 UTC 2026.
No Mesoscale Discussions are in effect as of Sat Apr 18 09:55:02 UTC 2026.
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1239 AM CDT Sat Apr 18 2026
Valid 191200Z - 201200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Severe thunderstorms are not expected on Sunday.
...Synopsis...
A strong mid-level trough will move slowly east from the Great Lakes
to the Northeast on Sunday. At the surface, a large area of high
pressure will extend from the Plains to the Midwest and Southeast.
This will help advance the cold front (and richer moisture) into the
Atlantic and the Gulf.
The prevalence of high pressure and a continental, dry airmass
across most of the country will lead to minimal thunderstorm chances
on Sunday. A few isolated thunderstorms could develop along the
front from eastern Georgia to eastern North Carolina before the
front moves offshore. Scattered thunderstorms are possible along the
eastern shore of the Florida Peninsula, but given the weak
instability, strong to severe concern remains minimal.
Finally, thunderstorms that form over the higher terrain in northern
Mexico on Sunday may move into parts of South Texas and the Edwards
Plateau before weakening in the increasingly hostile post-frontal
environment.
..Bentley.. 04/18/2026
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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0208 AM CDT Sat Apr 18 2026
Valid 201200Z - 211200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Severe storms are not expected on Monday.
...Discussion...
High pressure and a dry airmass will limit thunderstorm potential
across most of the CONUS on Monday. The only exceptions will be
across South Florida and parts of the Southwest into West Texas.
Across South Florida, mid 60s dewpoints are forecast to persist on
Monday which may allow for sufficient instability for scattered
storm development. Weak instability should limit any severe weather
threat with this activity.
Additional isolated storms are possible across parts of the
Southwest into portions of West Texas as moisture return may lead to
some weak instability. No severe storms are expected from this
activity.
..Bentley.. 04/18/2026
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Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0240 AM CDT Sat Apr 18 2026
Valid 211200Z - 261200Z
...DISCUSSION...
Initially dry conditions will keep the severe weather threat low on
D4/Tuesday. As a mid-level trough traverses the Rockies on Monday,
lee troughing will strengthen on D5/Wednesday. This will bring
substantial moisture return across the Plains. Given the early stage
moisture return, more than an isolated severe weather threat appears
unlikely on D5.
A more substantial severe weather threat is anticipated on Day
6/Thursday. The evolution of the mid-level trough still remains
unclear, but an overall pattern featuring broad troughing across the
southern/central Plains, moderate to strong instability, and a sharp
dryline, could support at least isolated supercells Thursday
afternoon/evening. Have added a 15% area from western/central
Oklahoma into southern/eastern Kansas where the severe weather
threat seems likely regardless of how exactly the mid-level pattern
evolves.
The uncertainties discussed for Day 6 become greater on Day 7 and
beyond. Persistent troughing across the Plains and considerable
instability suggest that severe weather is likely on Friday (and
likely into the weekend). However, the progression of the mid-level
trough and the associated surface features need to become more clear
before a 15% area can be defined for these days.
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0118 AM CDT Sat Apr 18 2026
Valid 181200Z - 191200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN AND CENTRAL
NEBRASKA...
...Synopsis...
An amplified upper trough will move towards the upper Great Lakes
and Ohio Valley as temporary upper ridging builds over the West. In
the wake of the upper trough, a post-frontal dry airmass and
northwesterly flow will promote widespread fire weather conditions
across portions of the central and southern Plains. Enhanced
southwest winds ahead of an eastward progressing cold front will
pose an Elevated fire weather threat across parts of the Southeast
and Mid-Atlantic.
...Central/southern Plains...
Within a post-frontal environment, northwesterly winds of 15-20 mph
and RH of 15-25 percent over dry fuels will pose an Elevated fire
weather threat for portions of the central and southern Plains this
afternoon. A confined region of northwesterly winds of up to 25 mph
and gusts over 30 mph are expected in central/western Nebraska.
Despite model guidance indicating daytime RH to remain above 15
percent within this region, strong winds atop recently receptive
fuels and expected 90th-95th percentile ERCs will promote Critical
fire weather concerns.
...Southeast/Mid-Atlantic...
Increasing southwest flow ahead of an advancing cold front coupled
with the lack of appreciable moisture return from the Gulf and
resultant low RH will promote an Elevated fire weather threat across
much of the Southeast into the Mid-Atlantic. At peak heating,
widespread RH of 20-30 percent will combine with southwesterly winds
of 10-15 mph atop receptive fuels. Thunderstorms are expected to
form along/ahead of the approaching cold front in the
southern/central Appalachians late afternoon into the overnight
hours. With relatively minimal precipitation (less than 0.25")
expected on eastern slopes of the Appalachians towards the Piedmont
Plateau, the potential exists for lightning ignitions. Given a
continuous environment of above normal temperatures and
exceptionally dry fuels, there is a concern for increased spread
potential of any existing and new ignitions.
..Elizalde-Garcia/Moore.. 04/18/2026
...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
0120 AM CDT Sat Apr 18 2026
Valid 191200Z - 201200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN PLAINS...
...Synopsis...
Upper ridging across the West will slide eastward over the
Continental Divide as an amplified large-scale trough will traverse
the eastern U.S. on Sunday. Broad northwest flow will prevail over
the High Plains as surface high pressure shifts east and lee surface
troughing enhances fire weather concerns over the southern Plains.
Beneath the aforementioned trough, an associated cold front will
advance off the Eastern Seaboard as a dry and breezy post-frontal
airmass will pose an elevated fire weather threat across much of the
Piedmont and Southeast.
...Central/southern Plains...
Dry return flow and lee surface troughing will result in continued
Elevated and Critical fire weather conditions on Sunday. A
combination of south-southwesterly sustained winds of up to 25 mph
(gusts up to 35 mph) and very low RH of 10-15 percent (single digits
locally) will pose a Critical fire weather threat over portions of
southwestern Kansas, southeastern Colorado, northeastern New Mexico,
and the OK/TX Panhandles. Poor overnight humidity recoveries and
mainly clear skies during the afternoon will further exacerbate the
fire environment amid 90th-97th percentile ERCs. High/mid-level
clouds will increase during the afternoon across West TX and eastern
NM, however, sustained surface winds from 10-20 mph with 10-15
percent RH atop dry fuels maintain an Elevated fire weather threat.
...Southeast/Mid-Atlantic...
In a post-frontal environment, dry and breezy northerly flow will
develop east of the Appalachians into the Southeast on Sunday.
North-northwest sustained winds of 10-15 mph and widespread low RH
of 15-30 percent atop exceptionally dry fuels will promote Elevated
fire weather conditions from the Mid-Atlantic to the Florida
Panhandle. Elevated highlights may be adjusted in future outlooks
depending on the anticipated rainfall on Day 1/Saturday into Day
2/Sunday morning.
..Elizalde-Garcia/Moore.. 04/18/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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