Mesoscale Discussion 2454
NWS Storm Prediction Center Norman OK
0735 AM CST Fri Nov 13 2026

Areas affected...Coastal far northern California

Concerning...Severe potential...Watch unlikely 

Valid 131335Z - 131530Z

Probability of Watch Issuance...5 percent

SUMMARY...A few convectively enhanced wind gusts could occur this
morning along the far northern California coast.

DISCUSSION...As a frontal band approaches, several
semi-organized/modestly bowing linear segments of convection are
noted in the pre-dawn hours in radar imagery off the coast of far
northern California amidst broader stratiform precipitation. While
this low-topped convection may not be deep enough to produce
lightning, it is conceivable that some convective enhancement may
influence wind gust potential as these bands progress
east-northeastward toward coastal areas this morning. Regarding the
robustly strong low-level wind field near the coast, latest WSR-88D
VWP data from KBHX is sampling 50-60 kt south-southwesterly winds
within the lowest 1-2 km AGL.

..Guyer.. 11/13/2026

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

ATTN...WFO...EKA...

LAT...LON   39622490 41112492 41942394 41252372 39452361 39622490 

MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0649 AM CST Fri Nov 13 2026

Valid 131300Z - 141200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Organized severe thunderstorms are not expected across the U.S.
today or tonight.

...Southwest States including southern Arizona...
A southern-stream shortwave trough near the SoCal/northern Baja
coast will continue generally eastward along the international
border, while a more prominent upper trough amplifies a bit more
along the West Coast toward the Great Basin. Ahead of the southern
stream trough, isolated thunderstorm development will become more
probable by late morning into the afternoon across southern Arizona
as forcing for ascent overspreads a modestly moist/unstable boundary
layer.

A few stronger low-topped storms could develop/spread
north-northeastward into south-central/southeast Arizona by around
mid-afternoon. Some small hail and/or gusty winds are plausible, but
current thinking is that organized severe thunderstorm potential
will be curbed by a trend of weakening low/mid-tropospheric flow
into this afternoon (effective shear 25 kt or less), along with the
relatively cool thermal profiles and perceived limitations on
downdraft intensity. A bit later in the day, a somewhat stronger
combination of deep-layer winds and lapse rates/buoyancy could also
contribute to some stronger storm potential toward the Rio Grande
River valley of southern New Mexico and far west Texas, but overall
severe potential should remain low.

Across northern California, while lightning flash potential will
likely remain limited, some convective enhancement to the
inland-spreading precipitation may influence some stronger
near-coastal wind gusts. Additional low-topped convection is
expected as lapse rates steepen within the post-frontal environment
later today for near-coastal areas and possibly parts of the
interior valley.

..Guyer/Mead.. 11/13/2026

Day 4-8 Convective Outlook  
NWS Storm Prediction Center Norman OK
0400 AM CST Fri Nov 13 2026

Valid 161200Z - 211200Z

...DISCUSSION...
The upper trough across the TX Gulf Coast is forecast to continue
eastward and weaken as ridging intensifies over the central US. The
strong surface response to the building ridge (1030-1035 mb) will
favor cool, dry and stable offshore flow over much of the CONUS.
Thunderstorms will likely be confined to the near-shore coastal
waters of the Gulf through the remainder of the weekend and into
early next week.

...Mid to late week...
Ensemble guidance eventually shows the upper ridge yielding to
increasingly strong western US troughing sometime mid to late week.
Model solutions vary, with AINWP guidance considerably stronger and
faster than physics-based ensembles with ejecting the deep upper
trough and surface low D5/Tues - D7/Thur. Regardless, it appears
likely that stronger southwesterly flow aloft will move eastward
from the Desert Southwest into the southern Rockies and eventually
the central US, with increasing thunderstorm chances mid to late
week next week. The prominent high pressure over the Midwest will
likely delay substantial moisture return, casting significant
uncertainty on any severe potential. Predictability remains low
through much of the forecast period.