268 
ACUS02 KWNS 111658
SWODY2
SPC AC 111656

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1056 AM CST Thu Dec 11 2025

Valid 121200Z - 131200Z

...NO THUNDERSTORM AREAS FORECAST...

...SUMMARY...
The risk for thunderstorms appears negligible across much of the
U.S. Friday through Friday night.

...Synopsis...

An upper ridge will persist near the Pacific coast while broad upper
troughing continues across the eastern U.S. Stronger flow aloft will
be displaced from the only appreciable, albeit modest, moisture
along the Texas coastal plain. A surface low over the OH/TN Valleys
will shift east toward the Mid-Atlantic late in the period, allowing
a weak cold front to develop south toward the western and central
Gulf coasts. Some thunderstorm activity could develop late in the
period over the western Gulf waters as a weak shortwave impulse
moves across northeast Mexico. However, thunderstorm activity is
expected to remain offshore, precluding 10 percent general thunder
probabilities.

..Leitman.. 12/11/2025

$$


File: /home/ldm/var/data/BY_SOURCE/KWNS/ACUS02/20251211T1658.txt



927 
ACUS02 KWNS 110530
SWODY2
SPC AC 110529

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1129 PM CST Wed Dec 10 2025

Valid 121200Z - 131200Z

...NO THUNDERSTORM AREAS FORECAST...

...SUMMARY...
The risk for thunderstorms appears negligible across much of the
U.S. Friday through Friday night.

...Discussion...
Downstream of a blocking mid-level high, maintaining near/north of
the Aleutians, it still appears that the evolving flow may include a
shortwave 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 may gradually
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 scattered deepening convective development prior to 12Z
Saturday.

...Texas coastal areas...
Latest guidance, including available forecast soundings from various
models, still suggests that the environment may become increasing
conducive to convection capable of producing lightning near lower
through middle coastal areas late Friday night.  Highest
probabilities for the initiation of at least a couple of weak
thunderstorms may be around 12Z Saturday, just east of the coastal
waters.  At least for now, thunderstorm probabilities will be
maintained at less than 10 percent, but, depending on trends in
later model runs, it is possible than minimum threshold thunderstorm
probabilities may still need to be reintroduced.

..Kerr.. 12/11/2025

$$


File: /home/ldm/var/data/BY_SOURCE/KWNS/ACUS02/20251211T0530.txt