Day 4-8 Outlook

Day 4-8 Convective Outlook  
NWS Storm Prediction Center Norman OK
0314 AM CST Wed Dec 10 2025

Valid 131200Z - 181200Z

...DISCUSSION...
Based on the latest medium-range model output, a vigorous digging
short wave trough is likely to contribute to substantive mid-level
trough amplification once again across the Upper Midwest/Great Lakes
and Ohio Valley, into and across the Mid Atlantic Seaboard this
coming weekend.  It appears that this may provide support for
significant cyclogenesis along a frontal zone across the
northwestern Atlantic, while a strongly confluent mid-level regime
in its wake supports the southeastward development of a large cold
surface ridge across most areas east of the Rockies, including the
offshore Atlantic and Gulf Basin by early next week.

Thereafter, into the middle of next week, mid-level flow may trend a
bit more zonal, at least across the northern mid-latitudes of North
America.  However, there is notable spread evident within and among
the various model output concerning short waves emerging from the
upstream blocking pattern, before progressing inland within
splitting branches of westerlies across and east of the Rockies. 
After an initial suppression of Gulf boundary-layer moistening early
next week, a developing southerly return flow with moistening that
may lead to increasing convective potential appears possible across
and northeast of the northwestern Gulf coast/lower Mississippi
Valley vicinity.  The extent to which this could include a risk for
severe storms remains unclear, but currently still appears generally
low through at least this period.

No Mesoscale Discussions are in effect as of Wed Dec 10 09:17:02 UTC 2025.

No watches are valid as of Wed Dec 10 09:17:02 UTC 2025.

SPC 0830Z Day 3 Outlook

Day 3 Convective Outlook  
NWS Storm Prediction Center Norman OK
0126 AM CST Wed Dec 10 2025

Valid 121200Z - 131200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
The risk for thunderstorms appears negligible across much of the
U.S. Friday through Friday night, aside from some possible weak
thunderstorm activity near Texas coastal areas prior to daybreak
Saturday.

...Discussion...
Downstream of a blocking mid-level high, maintaining near/north of
the Aleutians, it appears that the evolving flow may include a short
wave ridge building inland across British Columbia and the Pacific
Northwest during this period.  As this occurs, digging short wave
troughs farther downstream may reinforce larger-scale mid-level
troughing across parts of the northern Great Plains through Great
Lakes vicinity.  However, in general, models indicate that the
persistent cyclonic regime to the east of the Rockies will continue
to lose amplitude, with the stronger mid-level height gradient
tending to recede northward through the middle Mississippi/Ohio
Valleys and Mid Atlantic.  In lower levels, a leading surge of
colder air to the lee of the Rockies may stall and weaken across the
Mid South through south central Great Plains vicinity by late Friday
night.

In lower latitudes, mid-level heights may rise on the northwestern
periphery of Atlantic subtropical ridging, as far north as southern
Florida, downstream of weak mid/upper trough progressing across the
northern Mexican Plateau through northwestern Gulf Basin.  Beneath
this regime, it appears that gradual Gulf boundary-layer moistening
will continue.  In the vicinity of a weak surface trough forecast to
develop near Texas coastal areas by late Friday night, it is
possible that destabilization and forcing for ascent may become
conducive to weak thunderstorm activity.

..Kerr.. 12/10/2025

SPC 0700Z Day 2 Outlook

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1101 PM CST Tue Dec 09 2025

Valid 111200Z - 121200Z

...NO THUNDERSTORM AREAS FORECAST...

...SUMMARY...
The risk for thunderstorms appears negligible across the U.S.
Thursday through Thursday night.

...Discussion...
Downstream of an increasingly prominent blocking high building near
and to the north of the Aleutians, mid-level developments across the
eastern Pacific into western North America are still forecast to
include a belt of strong flow veering to an increasing northwesterly
component across British Columbia and adjacent portions of the
Pacific Northwest, through portions of the Canadian Prairies and
northern U.S. Great Plains during this period.  One or two short
wave perturbations on the leading edge of this regime will begin to
reinforce broad downstream troughing across the Mississippi Valley
into western Atlantic.

Mid-level flow is likely to remain cyclonic as far south as the Gulf
Coast states, but heights across much of the South may tend to rise
in the wake of a significant lower/mid-tropospheric cyclone forecast
to migrate out of the Northeast through the Canadian Maritimes. 
While progressing farther offshore to the north, it still appears
that the primary trailing frontal zone may stall/retreat
northeastward across the southern Atlantic Coast through Tennessee
Valley vicinity, while advancing southward through the lower
Missouri Valley and central Great Plains vicinity by late Thursday
night.  At the same time, much colder air probably will continue to
gradually nose southward to the lee of the Canadian and northern
U.S. Rockies.

Models indicate that a remnant preceding front will become more
diffuse across the central through northwestern Gulf Basin, and a
gradual boundary-layer modification may continue across the
northwestern Gulf as a weak southerly return flow begins to develop.
Some boundary-layer moistening appears possible inland across Texas
coastal areas, but forecast soundings indicate that this will occur
beneath pronounced warm/dry layers in the lower/mid-troposphere,
precluding appreciable destabilization through this period.

..Kerr.. 12/10/2025

SPC 1200Z Day 1 Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1154 PM CST Tue Dec 09 2025

Valid 101200Z - 111200Z

...NO THUNDERSTORM AREAS FORECAST...

...SUMMARY...
The risk for thunderstorms appears low today.

...Synopsis...
The large-scale pattern will feature a ridge across the western
CONUS with a trough across the east. A surface low will deepen below
990mb as it moves from the southern Great Lakes to the Northeast
during the period. A cold front will extend southwest from this
surface low and bring a reinforcing cold/dry airmass to much of the
central and eastern CONUS.

Significant moisture (60F dewpoints) will be relegated to far south
Florida. However, even here, northerly flow should persist within
the post frontal airmass. This should keep any thunderstorm
potential well offshore. A brief period of southerly return flow
across the western Gulf may bring some near 60F dewpoints to the
Texas coast, but this should be short-lived as a reinforcing cold
front moves offshore this evening.  

Thunderstorms are not expected across the CONUS today.

..Bentley/Thornton.. 12/10/2025

SPC Day 2 Fire Weather Outlook

Day 2 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
1152 PM CST Tue Dec 09 2025

Valid 111200Z - 121200Z

...NO CRITICAL AREAS...

...Synopsis...
Fire weather concerns are expected to remain low on D2/Thursday. The
pattern will continue to favor high amplitude ridging in the west
and troughing in the east. Westerly flow across the northern Rockies
and surface troughing across the Plains will allow for some overlap
of downslope flow with dry conditions across the central and
southern High Plains. Fuels across these regions are not receptive
to large fire spread, which will help mitigate any fire weather
concerns.

..Thornton.. 12/10/2025

...Please see www.spc.noaa.gov/fire for graphic product...

SPC Day 1 Fire Weather Outlook

Day 1 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
1151 PM CST Tue Dec 09 2025

Valid 101200Z - 111200Z

...NO CRITICAL AREAS...

...Synopsis...
Fire-weather concerns are expected to remain low today across the
CONUS. The pattern will be defined by a longwave trough across the
east and a high amplitude ridge across the west. Between these two
features, generally northerly flow will over spread the Plains amid
surface high pressure. Some areas of dry/breezy conditions will be
possible across western and north-central Texas where daytime highs
are expected to be warm. Fire-weather concerns will be limited by
lack of receptive fuels for large wild-fire spread.

..Thornton.. 12/10/2025

...Please see www.spc.noaa.gov/fire for graphic product...