RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Sun Apr 19 22:23:01 UTC 2026.
No Mesoscale Discussions are in effect as of Sun Apr 19 22:23:01 UTC 2026.
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0255 PM CDT Sun Apr 19 2026
Valid 192000Z - 201200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Severe thunderstorms are not forecast today.
...20Z Update...
The TSTM area was removed in eastern NC, where the cold front and
related thunderstorm potential has shifted offshore. The TSTM area
was also trimmed behind a band of eastward-moving thunderstorms
departing the New England coast, and no lightning is expected behind
this activity. Farther south in parts of central FL, isolated
thunderstorms are evolving along the sea breeze focused over the
Treasure Coast. While storm coverage and intensity are expected to
remain isolated/marginal, a warm/unstable PBL and around 35 kt of
midlevel flow could support a strong storm or two capable of locally
strong gusts, though this activity is expected to remain sub-severe.
..Weinman.. 04/19/2026
.PREV DISCUSSION... /ISSUED 1059 AM CDT Sun Apr 19 2026/
...Synopsis...
A shortwave trough currently approaching Baja California will
provide increasing large-scale forcing for ascent over Mexico and
south/west TX today. This will lead to scattered thunderstorms
through the period.
Other isolated afternoon thunderstorms are expected ahead of a
frontal band affecting New England and eastern NC, beneath cold air
aloft in the Lower Great Lakes region, and over south FL. In all of
these areas, weak instability and/or limited vertical shear will
preclude a risk of organized severe storms.
Read more
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0236 PM CDT Sun Apr 19 2026
Valid 211200Z - 221200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Thunderstorms will be possible across the western CONUS, the
south-central CONUS, and the southern Great Lakes on Tuesday.
Potential for severe weather appears low.
...Synopsis...
Upper ridging will be the primary feature across much of the CONUS
from the eastern Great Basin into Plains on Tuesday. Moderate
northwesterly flow aloft will remain across the Upper Midwest and
portions of the Ohio Valley in the wake of a stronger upper trough.
Along the West Coast, an upper trough is expected to slowly move
ashore in central California into the western Great Basin. At the
surface, continued presence of high pressure in the Southeast and
off the Atlantic coast will drive moisture return into a
stalled/remnant cold front in central Plains and Lower Great Lakes
vicinity.
...Lower Great Lakes...
Modest moisture return ahead of the boundary is expected to promote
isolated to widely scattered thunderstorms. This may not occur until
early/mid evening, however. Temperatures will be quite cold aloft
(perhaps near -20 C at 500 mb), but moisture could be quite limited
(potentially in the 40s F). The NAM is again the most aggressive
with moisture return as compared to other guidance. Should
sufficient moisture return occur, shear will be sufficient for
marginally organized convection capable of strong gusts and hail.
Uncertainty is high given how dry the airmass is preceding this
moisture return and convection near the Gulf Coast on preceding days
will potentially slow northward progress.
...Central Valley California...
Ahead of the upper low, southeasterly winds may develop within the
Valley. While destabilization will not be overly strong, pockets of
heating could lead to modest MLCAPE values by the afternoon. Shear
will be a limiting factor for overall severe potential, but a
stronger storm or two is possible.
...Central Texas...
Convection will be ongoing early Tuesday morning. Modest deep-layer
shear and elevated buoyancy could promote a couple stronger storms
capable of small hail. However, storms should generally become less
organized with time as upper-level ridging builds in through the
day.
..Wendt.. 04/19/2026
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0155 PM CDT Sun Apr 19 2026
Valid 201200Z - 211200Z
...Afternoon Update...
Only minor changes were made to expand and confine the Elevated fire
weather highlights based on recent high resolution guidance. Across
the Piedmont, partly cloudy skies may increase RH values and inhibit
deeper mixing across some parts of the region on Monday afternoon.
However, poor overnight humidity recoveries and westerly winds of
10-15 mph in terrain influenced areas will continue to support an
Elevated fire weather threat. In the Southeast, northeasterly winds
of up to 15 mph (gusts up to 20 mph) are expected where
exceptionally dry fuels exist. Despite winds decreasing slightly
throughout the day, areas where very low RH of 15-20 percent and
gustier winds overlap may promote locally critical fire weather
conditions. Farther west, portions of eastern WY may experience
localized critical fire weather conditions where sporadic gusts of
up to 35 mph are possible in the lee of the Laramie Mountains.
However, lack of mid-level support and the narrow duration of strong
winds overlapping low RH precludes the introduction of critical
highlights at this time.
Increasing mid-level moisture with afternoon heating and resultant
instability may support isolated thunderstorms across south-central
NM into eastern AZ. PWATs of 0.5-0.75" with a prominent dry
sub-cloud layer should limit precipitation, allowing for the threat
of dry thunderstorms to evolve. While widespread ERCs are below the
90th percentile in this region, recent fire activity depicts
receptivity where pockets of drier fuels exist.
See the previous discussion for more information.
..Elizalde-Garcia.. 04/19/2026
.PREV DISCUSSION... /ISSUED 0204 AM CDT Sun Apr 19 2026/
...Synopsis...
Areas of elevated fire weather conditions are expected across parts
of the High Plains and the Southeast on Monday. Upper-level ridging
will gradually shift east from the Rockies into the Plains through
the day. While surface high pressure shifts east over the Southeast
states, a lee trough will deepen along the northern High Plains,
resulting in areas of breezy conditions over dry fuels.
...High Plains...
A deepening lee trough along the northern High Plains will support
strengthening west/southwest winds to the west of the trough axis
across eastern WY into western NE. Further south, a tightening
pressure gradient in proximity to a lingering surface high over
eastern TX will promote strengthening winds across the OK/TX
Panhandle region. Within both regimes, ensemble guidance suggests
sustained winds between 15-20 mph are likely. RH minimums in the
teens are likely across WY into NE where downslope wind will depress
moisture content within an antecedent dry air mass. Further south,
the northern fringe of returning moisture will begin nosing into
western TX. This may limit RH reductions to some degree, but RH
minimums will likely fall into at least the low 20s given model
guidance tendency to display a moist bias at the surface within the
early stages of moisture return.
...Southeast...
A dry air mass will reside across much of the Southeast where fuels
will likely remain dry owing to limited rainfall forecast over the
next 24-48 hours for much of the region. In general, gradient winds
will weaken through the day as surface high pressure builds across
the region. However, areas of breezy conditions will likely persist
in the lee of the southern Appalachians and along the northeastern
Gulf coast. Sustained winds near 15 mph within a dry air mass (RH
minimums in the teens to twenties) will likely support another day
of elevated fire weather conditions.
...New Mexico to eastern Arizona...
Low to mid-level moisture return is anticipated across southern TX
and into central NM through Monday afternoon. Although forcing for
ascent will be modest under an upper-level ridge, a combination of
localized orographic ascent and deeply mixed boundary-layers with
minimal inhibition will support isolated thunderstorm development.
Storm motions around 10 knots will likely support pockets of wetting
precipitation, but PWAT values between 0.6 to 0.7 inches will likely
support dry lightning strikes outside of the heavier precipitation
cores. With regional ERCs near the 75th to 80th percentile,
lightning ignitions appear possible.
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0444 PM CDT Sun Apr 19 2026
Valid 211200Z - 271200Z
...Synopsis...
A large scale upper trough will move onshore the West Coast as
ridging slides over the eastern CONUS on Day 3/Tuesday.
Precipitation will be possible for parts of the Mid-Atlantic and
northern Appalachians with an associated shortwave trough on Day
4/Wednesday. However, much of the Piedmont into the Southeast will
remain fairly dry through the week as surface high pressure builds
across the region through Day 6/Friday. As the aforementioned trough
and associated mid-level flow progress eastward into the northern
Plains mid-week, fire weather concerns are expected to reemerge
across portions of the Southwest and High Plains. Through the end of
the forecast period, persistent western troughing will likely
maintain continued fire weather concerns where dry fuels exist.
...Day 3-5/Tuesday-Thursday...
...Florida, Mid-Atlantic, and Southeast...
A fire weather threat will continue for portions of Florida on Day
3/Tuesday as surface high pressure settles into the Deep South.
Breezy easterly winds of up to 10 mph (gusts up to 15 mph) and RH
values between 15-30 percent amid 90-99th percentile ERCs support
40% Critical probabilities. On Day 4/Wednesday, a shortwave impulse
will bring precipitation chances across portions of the Mid-Atlantic
along a weak cold front. Ahead of the front, strong mid-level flow
aloft will support dry and breezy downslope conditions where
97th-99th percentile ERCs have been observed across the Carolinas.
40% Critical probabilities have been introduced to account for this
threat.
...Central and Southern Plains...
A deepening surface low across the northern High Plains ahead of the
approaching upper-level trough and associated southwest flow aloft
will bring a more expansive fire weather threat to much of the High
Plains and portions of the Southwest mid-week where fuels remain
receptive. 70% critical probabilities have been maintained for Day
4/Wednesday where a mid-level jet aligns with tightening surface
pressure gradients associated with the deepening lee trough.
Downslope enhanced drying and stronger west/southwest winds will
continue across much of the Southwest and Southern Plains on Day
5/Thursday as the mid-level trough ejects into the Plains. Broad 40%
critical probabilities were maintained for the Southwest and
Southern Plains.
..Elizalde-Garcia.. 04/19/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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