RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Tue Jan 20 20:58:02 UTC 2026.
No Mesoscale Discussions are in effect as of Tue Jan 20 20:58:02 UTC 2026.
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0144 PM CST Tue Jan 20 2026
Valid 202000Z - 211200Z
...NO THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Thunderstorms are not forecast across the U.S. today or tonight.
...20Z Update...
No changes are needed to the ongoing forecast.
..Wendt.. 01/20/2026
.PREV DISCUSSION... /ISSUED 0953 AM CST Tue Jan 20 2026/
...Discussion...
A prominent longwave trough will remain entrenched from the Rockies
to the western Atlantic, with a general prevalence of cold/dry
continental trajectories and surface high pressure over the eastern
third of the CONUS. Airmass modification will occur with a modest
increase in low-level moisture toward coastal Texas tonight.
However, instability is expected to remain too limited to support
thunderstorms through tonight.
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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1045 AM CST Tue Jan 20 2026
Valid 211200Z - 221200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Widely scattered weak thunderstorm activity is possible Wednesday
into Wednesday evening across parts of southeastern Texas into the
lower Mississippi Valley.
...Discussion...
While an initially prominent mid-level ridge, centered offshore of
the Pacific Northwest/British Columbia coast into Alaska, will
undergo more notable weakening through this period, models indicate
that large-scale downstream troughing will generally be maintained
across much of interior and eastern North America. It appears that
this will be reinforced by a strong short wave trough emerging from
the Canadian Arctic latitudes, before digging around the western
periphery of Hudson Bay, toward the central international border
area. This is forecast to be accompanied by modest cyclogenesis
across and northeast of the Great Lakes, and a more notable
reinforcing cold intrusion into the Ohio and Missouri Valleys, in
the wake of a preceding one reaching the Mid Atlantic, northern Gulf
Coast states and Texas Gulf coastal plain by 12Z Wednesday
At the same time, it still appears that much of the southern tier of
the U.S. will continue to come under the increasing influence of
westerlies emanating from the southern mid- to subtropical latitudes
of the eastern Pacific. Within this regime, a notable developing
mid-level low is forecast to slowly dig toward the southern
California/northern Baja coast, downstream of a building short wave
ridge over the mid-latitude eastern Pacific. While forecast
soundings suggest that this may be preceded by an inland spreading
band of weak convection, associated with mid/high-level moisture
return from the lower latitude eastern Pacific, the modest and
relatively compact mid-level cold core of the low is forecast to
remain offshore through this period. This will minimize the risk
for boundary-layer destabilization, and any appreciable potential
for convection capable of producing lightning, across and inland of
coastal areas.
Downstream, lower/mid-tropospheric moisture return is likely to
continue across parts of southern/eastern Texas into the lower
Mississippi Valley Wednesday through Wednesday night. Although, in
lower levels, this will be off a still modifying western Gulf
boundary layer, it appears that elevated inland moistening, beneath
the southern periphery of colder mid-level air slowly retreating to
somewhat higher latitudes, will contribute to weak elevated
destabilization. Forecast soundings continue to suggest that this
may become sufficient to support convection capable of producing
lightning, mainly in a corridor from southeast Texas
east-northeastward through the lower Mississippi Valley, aided by
forcing for ascent associated with one or two short wave
perturbations within the lingering cyclonic flow.
..Kerr.. 01/20/2026
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SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0102 PM CST Tue Jan 20 2026
Valid 221200Z - 231200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Aside from the risk for a couple of thunderstorms near southern
Florida Atlantic coastal areas, potential for thunderstorms appears
minimal across much of the U.S. Thursday through Thursday night.
...Discussion...
Models indicate that a significant short wave trough emanating from
the Arctic latitudes will continue digging across and southeast of
the central Canadian/U.S. border through this period, reinforcing
broad, cold mid-level troughing across the northern U.S. Great
Plains through middle and northern Atlantic Seaboard. In lower
latitudes, flow is forecast to remain broadly cyclonic as far south
as the northern Gulf Basin, but with a continued slow/subtle warming
in mid-levels across much of the Gulf Coast states, downstream of a
slowly digging mid-level low offshore of the southern
California/northern Baja coast. It appears that the modest and
compact mid-level cold core of this low will remain offshore through
at least this period, as a sharp upstream ridge builds a bit further
northward through the mid-latitude eastern Pacific.
Beneath this regime, it appears that the primary frontal zone may
remain quasi-stationary across the Carolinas through northern
portions of the eastern Gulf Coast states. However, some further
southward advancement is possible across the Ark-La-Miss and central
Texas by late Thursday night, as a prominent cold surface ridge
continues to build along an axis across the Canadian Prairies
through middle and lower Missouri Valley.
Some further low-level moistening is possible to the south of this
front, off a slowly modifying Gulf and southwestern Atlantic
boundary layer. However, beneath slowly warming mid-levels, with
weak mid/upper support for convective development, the risk for
thunderstorms appears limited Thursday through Thursday night.
...Southern Florida...
A consensus of latest available model output, ranging from ECENS and
GEFS convective precipitation forecasts to NAM/Rapid Refresh
forecast soundings and NAM/RRFS convection allowing guidance,
suggests that at least minimum threshold thunderstorm probabilities
may become focused during this period in the vicinity of weak
surface troughing developing near southern Florida Atlantic coastal
areas. This appears possible in response to increasing
boundary-layer destabilization and convergence, perhaps aided by
forcing associated with weak perturbations within the subtropical
westerlies.
..Kerr.. 01/20/2026
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1059 AM CST Tue Jan 20 2026
Valid 201700Z - 211200Z
Broad northwesterly flow aloft ahead of an approaching mid-level
short wave will persist over the Southern Rockies. A deepening
surface low currently across the northern High Plains is still
expected to drop southward into southeastern CO by late afternoon.
Resultant downslope flow in the lee of the Rockies is supporting
current RH values below 10 percent across south-central CO. The dry
conditions and receptive fuels will combine with west winds of 15-20
mph to bring a elevated fire weather conditions to locations in the
lee of the Sangre de Cristo Mountains in southern CO through this
afternoon. A broader east-northwest wind field of 15-20 mph across
northeastern CO, southwestern NE, and northwest KS along with RH
reductions in the 15-20 percent range amid receptive fuels will
support an elevated fire weather threat today. Veering winds
associated with an advancing cold front will move into northeast CO
and vicinity by late afternoon, allowing for colder temperatures and
rising RH within northerly flow to diminish fire weather concerns
this evening.
..Williams.. 01/20/2026
.PREV DISCUSSION... /ISSUED 0145 AM CST Tue Jan 20 2026/
...Synopsis...
A low-amplitude shortwave trough and accompanying speed maximum will
cross the central Rockies during the afternoon, while an attendant
surface low tracks south-southeastward along the northern/central
High Plains. Related downslope flow will yield 10-15 percent RH
across much of the central High Plains, where around 20 mph
sustained northwesterly surface winds (with higher gusts) are
expected. These dry/windy conditions will favor elevated to locally
critical fire-weather conditions over northeastern CO, southwestern
NE, and northwest KS. A separate corridor of elevated fire-weather
conditions is expected in the lee of the Sangre de Cristo Mountains
in southern CO, with locally critical conditions possible within the
gap flow areas. Between these two corridors, recent snowfall should
limit fire-weather concerns.
Elsewhere, modestly breezy northeasterly surface winds are expected
amid a dry antecedent air mass across parts of the western and
central FL Peninsula, where locally elevated fire-weather conditions
are possible.
...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
0148 PM CST Tue Jan 20 2026
Valid 211200Z - 221200Z
...NO CRITICAL AREAS...
...Central High Plains...
Broad northwesterly flow over the southern Rockies and lee surface
trough development across the central High Plains is expected
Wednesday. This will support localized dry and breezy downslope
westerly winds along the foothills and adjacent high plains of CO
Front Range and Sangre De Cristo Mountains into north-central NM.
Elevated fire weather conditions are likely to be limited to favored
terrain gaps where sustained winds of around 15 mph with higher
gusts align with RH in the 15-20% range and receptive fuels.
Farther north, another cold front moves into the Central Plains
Wednesday, bringing gusty northwest winds of 15-20 mph to far
northeastern CO and western NE. Increasing cloud cover, cooler
temperatures and RH reductions between 20-25% should limit overall
fire weather threat. Nonetheless, the breezy winds along with fuels
that remain quite receptive could bring a localized and brief
elevated fire weather threat to southeast WY, far northeastern CO
and southwestern NE Wednesday.
..Williams.. 01/20/2026
.PREV DISCUSSION... /ISSUED 0145 AM CST Tue Jan 20 2026/
...Synopsis...
Fire-weather concerns are minimal on Wednesday, as a cold air mass
begins to infiltrate the central U.S.
...Please see www.spc.noaa.gov/fire for graphic product...
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