RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Wed Nov 19 21:53:01 UTC 2025.
No Mesoscale Discussions are in effect as of Wed Nov 19 21:53:02 UTC 2025.
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0201 PM CST Wed Nov 19 2025
Valid 192000Z - 201200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHWEST AND SOUTHERN PLAINS TO OZARKS...
...SUMMARY...
Isolated severe thunderstorms may occur across the southern Plains
into parts of the Ozarks, mainly late this afternoon into tonight.
Large hail should be the main threat, but occasional gusty winds and
perhaps a tornado may also occur.
...20Z Update...
The forecast remains on track and only minor adjustments were made
with this update. In parts of north TX, the latest visible satellite
imagery is showing initial signs of deepening boundary-layer cumulus
in the vicinity of an east/west-oriented quasi-stationary surface
boundary. Some high-resolution guidance depicts isolated
thunderstorm development in the general area during the late
afternoon/early evening time frame. Around 1000-1500 J/kg MLCAPE and
an elongated hodograph (around 40 kt of effective shear) would
conditionally support a supercell or two if storms can initiate.
However, weak/minimal forcing for ascent (both synoptic and
mesoscale) limits confidence in the initiation and sustenance of
storms during the afternoon hours. Given the conditionality, held
off on an upgrade to Slight Risk at this time, though a locally
favorable corridor for large hail is possible.
..Weinman.. 11/19/2025
.PREV DISCUSSION... /ISSUED 1030 AM CST Wed Nov 19 2025/
...Southern Plains to Ozarks...
A low-latitude mid/upper-level will move slowly eastward across the
lower Colorado River Valley/Southwest and northwest Mexico today
into tonight. Enhanced southwesterly mid-level flow will persist
across much of the southern Plains into the Ozarks and vicinity
through the period, although height falls will generally not reach
these locales until tonight. An increasingly moist low-level airmass
across south/central Texas this morning will advance slowly
northward in tandem with a surface warm front. Weak lee cyclogenesis
should occur this evening and overnight across west Texas as
large-scale ascent preceding the slow-moving upper trough eventually
overspreads the southern Plains. Nebulous forcing for much of the
day casts significant uncertainty on convective development across
the warm sector until later this evening and overnight.
But it appears probable that thunderstorms will gradually increase
in coverage this evening into early Thursday morning across the
southern Plains with the approach of the upper trough. Modest
low-level warm advection in the vicinity of the warm front and a
developing dryline across west Texas may also aid in convective
development this evening. Most guidance continues to show moderate
instability in place along/near these boundaries, with modestly
steepened mid-level lapse rates present. This favorable
thermodynamic environment, coupled with moderate to strong
deep-layer shear given the enhanced southwesterly flow aloft, should
promote organized updrafts.
Current expectations are for a mix of supercells and multicells to
develop and pose an isolated threat for mainly large hail. Where
convection can remain surface-based this evening, some threat for
occasional gusty winds and perhaps a tornado or two should also
exist, although the coverage and likelihood is uncertain. With time,
updraft interactions/mergers should result in a messy convective
mode, especially with elevated thunderstorms to the north of the
warm front. Still, at least some risk for severe hail may persist
for much of the overnight/early Thursday morning period with this
activity as it spreads east-northeastward across the southern Plains
and parts of the Ozarks. Additional development should occur late
tonight/early Thursday across eastern New Mexico into northwest
Texas with hail possible.
...Southeast Arizona/Southwest New Mexico...
Cool mid-level temperatures will be in place over the Southwest as
the upper trough progresses slowly eastward. Cooling aloft and cloud
breaks will allow for modest diurnal destabilization coincident with
strong deep-layer wind profiles. A few strong to locally severe
storms could occur with gusty winds and some hail.
Read more
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1123 AM CST Wed Nov 19 2025
Valid 201200Z - 211200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE SOUTHERN PLAINS...
...SUMMARY...
Isolated severe thunderstorms are possible across the southern
Plains tomorrow (Thursday). An instance or two of severe wind, hail,
or a brief tornado may occur.
...Synopsis...
The upper-air pattern across much of the western and central U.S.
tomorrow (Thursday) will be characterized by broad mid-level
troughing, with multiple embedded shortwave troughs rotating around
the broader scale cyclonic flow aloft. One upper trough will pivot
southeastward along the CA coastline with cooler temperatures aloft,
supporting isolated lightning flashes. A second mid-level shortwave
trough will eject into the Plains during the day, encouraging a
continued northward flux of rich low-level moisture amid a warm-air
advection regime. Strong forcing for ascent will promote an increase
in coverage of thunderstorms through the period across the southern
Plains as the mid-level trough overspreads the region. Despite
expected meager instability, strong vertical wind shear will
accompany the mid-level trough, which may support isolated strong to
potentially severe storms.
...Southern Plains...
The aforementioned broad upper troughing will support a relatively
prolonged low-level warm-air/moisture advection regime, where
low-level confluence will support widespread showers and at least
scattered thunderstorms at the start of the period (12Z Thursday),
from central TX to central OK. Given expected widespread cloudiness
and mediocre mid-level lapse rates, buoyancy should be quite weak
initially. However, with daytime heating, some boundary-layer mixing
(albeit modest), should help boost MLCAPE to several hundred J/kg.
While deep-layer vertical flow/shear should remain largely
unidirectional, some of the latest guidance suggests that slightly
stronger flow aloft will overspread the warm sector compared to
earlier guidance members. As such, considerable size/elongation of
the hodographs will result in 40-50 kts of effective bulk shear,
with some backing of the low-level winds possible closer to the
surface low in northern TX into OK. While this shear profile would
support severe potential, the presence of widespread clouds,
training thunderstorms, and poor tropospheric lapse rates (and
resultant buoyancy) should limit severe potential.
The current thinking is that a few stronger thunderstorms will form
within a confluence axis just ahead of the aforementioned training
thunderstorms in central OK to central TX by mid to late afternoon.
Given favorable vertical wind shear, multicells and supercells will
be possible initially, before unidirectional flow encourages the
development of a loosely organized line of storms. Discrete storms
will have the best potential for producing an instance or two of
marginally severe wind or hail. A brief tornado is also possible
with the storms that are closer to the surface low over northern TX
to central/eastern OK. Since most of the available buoyancy will
likely be driven by boundary-layer heating, the severe threat is
expected to wane after dark.
..Squitieri.. 11/19/2025
Read more
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0112 PM CST Wed Nov 19 2025
Valid 211200Z - 221200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Scattered thunderstorms are expected from the Texas coast into the
Tennessee Valley and central/southern Appalachians on Friday. Severe
thunderstorms are not expected.
...Synopsis...
A low-amplitude mid-level trough will overspread the TN Valley as an
upper-low becomes established over CA on Day 3/Friday. Cooler
temperatures aloft associated with the CA low will support a few
lightning flashes, mainly offshore. Across the TN Valley, the
passage of the low-amplitude mid-level trough will encourage the
eastward translation of a weak surface low along the OH River toward
the Appalachians through the Friday period. A broad fetch of
low-level moisture will advect northward toward the OH River has a
cold front slowly approaches from the Ozarks (draped southwestward
into eastern TX). The warm sector south of the warm front along the
OH River, and ahead of the cold front east of the Ozarks, should be
adequately buoyant to support isolated to scattered thunderstorm
development through the day Friday into Friday evening.
Nonetheless, the aforementioned mid-level trough should further
de-amplify through Friday, with forcing for ascent expected to
weaken as low-level flow heavily veers with time. Furthermore, the
mainly unidirectional vertical wind shear will become increasingly
displaced from the richer low-level moisture and associated
buoyancy, limiting severe potential across the OH Valley and points
south/west.
..Squitieri.. 11/19/2025
Read more
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0109 PM CST Wed Nov 19 2025
Valid 201200Z - 211200Z
...NO CRITICAL AREAS...
No changes are needed to the D2 Fire Weather Outlook. See previous
discussion below for more information.
..Thornton.. 11/19/2025
.PREV DISCUSSION... /ISSUED 0109 AM CST Wed Nov 19 2025/
...Synopsis...
Critical fire weather conditions are not expected Thursday across
the country. Latest short/medium-range guidance shows strong
agreement in widespread rainfall across the southern Plains as an
upper trough gradually shifts east. Some increase in westerly
downslope flow is expected across parts of far West Texas with
sustained winds between 15-20 mph possible. Despite ongoing drought,
moist conditions upstream coupled with rainfall chances over the
next 24 hours should modulate RH reductions and fuel status. Further
east, dry conditions may persist across portions of the Southeast;
however, surface high pressure will limit wind speeds and the
overall fire weather concern.
...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
0250 PM CST Wed Nov 19 2025
Valid 211200Z - 271200Z
Fire weather concerns will remain low during the D3-8 (Friday -
Wednesday) outlook period.
Status of fuels will largely be mitigated by widespread rainfall
forecast across much of the West, Southern Plains, portions of the
Southeast, and the Mid-Atlantic from multiple cool/moist trough
passages across the southern US. The exceptions will be portions of
western Texas and Georgia into the Carolinas, where little to no
rainfall is forecast and pockets of dry fuels will remain. Wind
across these regions should remain below critical thresholds which
will mitigate fire weather concerns.
..Thornton.. 11/19/2025
...Please see www.spc.noaa.gov/fire for graphic product...
Read more
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