Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1127 PM CST Sun Dec 14 2025

Valid 151200Z - 161200Z

...NO THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Thunderstorm probabilities are low today.

...Pacific Northwest...

100+kt 500mb speed max is forecast to translate inland along the
WA/OR coast around 16/00z. Low-amplitude short-wave trough will
induce strong height falls near the international border ahead of
this feature, coincident with a notable surface front that will
surge inland after 21z. While profiles will cool and steepen at
midlevels, forecast soundings are not particularly buoyant either
side of the trough, and the prospect for deep convection capable of
generating lightning appears low. While the thunderstorm potential
appears low, weak midlevel convection is possible and a flash or two
can not be ruled out. This, however, does not warrant a categorical
risk for thunderstorms during the day1 period.

..Darrow/Wendt.. 12/15/2025

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1259 AM CST Mon Dec 15 2025

Valid 161200Z - 171200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Isolated thunderstorms may occur over parts of the Pacific Northwest
on Tuesday/Tuesday evening, with isolated thunderstorms also
possible over the Texas Coastal Plain early Wednesday morning.

...Pacific Northwest...
A strong mid-level jet streak will approach the Pacific Northwest
coast Tuesday evening. At the surface, a strong cold front will move
onshore and bring the potential for some stronger thunderstorms.
Weak instability is forecast to develop ahead of the surface cold
front off the OR/WA coast Tuesday afternoon/evening. A stronger line
of convection is expected to develop along the front as it
approaches the coast Tuesday evening. Given the very strong wind
field (nearly 100 knots at 500mb), some stronger wind gusts may
develop within the convective line. Forecast instability is quite
weak (100 to 200 J/kg MLCAPE) which casts some doubt on the
efficiency for the stronger mid-level flow to mix to the surface.
This is the primary factor precluding a 5% wind area at this time.
Instability will wane quickly inland and therefore, any stronger
wind gusts will likely be confined to areas along the coast. 

...Texas Coastal Plain...
A weak mid-level shortwave trough will move across Texas during the
day on Tuesday. Mid-level forcing will be weak, but a modest
low-level jet will develop across East Texas and persist through the
day. This will bring some return moisture to the Texas Coastal
Plain. Eventually, likely after 06Z, the combination of moistening
low-levels and slightly cooling temperatures aloft will result in
sufficient destabilization for a few isolated thunderstorms within
the zone of isentropic ascent across East Texas.

..Bentley.. 12/15/2025

Day 3 Convective Outlook  
NWS Storm Prediction Center Norman OK
0215 AM CST Mon Dec 15 2025

Valid 171200Z - 181200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
A few isolated thunderstorms are possible in the Texas Coastal Plain
Wednesday morning. Scattered thunderstorms are possible early
Thursday morning from the Ozarks to the Lower Ohio River Valley.

...Synopsis...
A strong mid-level jet streak and associated shortwave trough over
the Pacific Northwest on Wednesday morning will move quickly across
the Rockies and amplify as it enters the Plains late Wednesday into
early Thursday morning. A very strong surface low, associated with
this fast-moving trough, will move from British Columbia Wednesday
morning to the Upper Midwest by early Thursday morning. 

A few thunderstorms may persist early Wednesday within a region of
weak isentropic ascent across East Texas. However, as the low-level
jet veers/weakens, this threat is expected to wane. High pressure
will continue to dominate much of the daytime period across the
eastern CONUS which should limit any thunderstorm potential.
However, by Wednesday night, thunderstorm potential is expected to
increase from the Texas Coastal Plain to the Lower Ohio River
Valley. As the mid-level trough amplifies across the Plains, a
low-level jet will rapidly strengthen from East Texas to the Ozarks.
This will advect low-level moisture northward during the evening.
After 06Z, weak to potentially moderate elevated instability is
expected within a broad region of weak isentropic ascent from
Arkansas to southern Illinois. Effective shear (based on an elevated
parcel) is expected to remain very weak early Thursday morning as
the primary mid-level jet streak is not forecast to emerge over the
warm sector until later Thursday morning. Therefore, no severe
weather is anticipated on Day 3/Wednesday.

..Bentley.. 12/15/2025