No watches are valid as of Tue Jan 20 17:52:02 UTC 2026.No Mesoscale Discussions are in effect as of Tue Jan 20 17:52:02 UTC 2026.SPC 1630Z Day 1 Outlook

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0953 AM CST Tue Jan 20 2026
Valid 201630Z - 211200Z
...NO THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Thunderstorms are not forecast across the U.S. today or tonight.
...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.
..Guyer/Lyons.. 01/20/2026
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
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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