910
ACUS02 KWNS 211704
SWODY2
SPC AC 211702
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1102 AM CST WED JAN 21 2026
VALID 221200Z - 231200Z
..NO SEVERE THUNDERSTORM AREAS FORECAST
..SUMMARY
ASIDE FROM THE RISK FOR A FEW WEAK THUNDERSTORMS NEAR SOUTHEASTERN
FLORIDA COASTAL AREAS, POTENTIAL FOR THUNDERSTORM DEVELOPMENT
APPEARS LOW ACROSS THE U.S. THURSDAY THROUGH THURSDAY NIGHT.
..DISCUSSION
A VIGOROUS SHORT WAVE TROUGH EMANATING FROM THE CANADIAN ARCTIC
LATITUDES IS FORECAST TO DIG SOUTHEAST OF THE INTERNATIONAL BORDER,
ACROSS PARTS OF THE UPPER MIDWEST AND GREAT LAKES REGION, AND
CONTRIBUTE TO THE MAINTENANCE OF LARGER-SCALE MID-LEVEL TROUGHING
ACROSS THE NORTHERN U.S. GREAT PLAINS THROUGH NORTHERN AND MIDDLE
ATLANTIC SEABOARD. BENEATH AN INCREASINGLY CONFLUENT REGIME IN ITS
WAKE, MODELS CONTINUE TO INDICATE THAT A RATHER PROMINENT, COLD
SURFACE RIDGE WILL BUILD SOUTHEASTWARD ALONG AN AXIS ACROSS THE
MIDDLE/LOWER MISSOURI VALLEY INTO LOWER OHIO VALLEY BY LATE THURSDAY
NIGHT.
IT APPEARS THAT A PRECEDING SURFACE FRONTAL ZONE WILL STALL AND
PERHAPS STRENGTHEN ACROSS THE CAROLINAS THROUGH NORTHERN PORTIONS OF
THE GULF COAST STATES INTO SOUTHERN GREAT PLAINS. ANOTHER IS
EXPECTED TO SLOWLY WEAKEN ACROSS THE FLORIDA PENINSULA AND NORTHERN
GULF BASIN, AS MUCH OF THE SOUTHERN TIER OF THE U.S. CONTINUES TO
COME UNDER THE INCREASING INFLUENCE OF WESTERLIES EMANATING FROM THE
MID- TO SUBTROPICAL EASTERN PACIFIC.
DOWNSTREAM OF FAIRLY SHARP BUILDING MID-LEVEL RIDGING ACROSS THE
EASTERN MID-LATITUDE PACIFIC, MODELS HAVE COME IN BETTER AGREEMENT
CONCERNING A DIGGING MID-LEVEL TROUGH AND EMBEDDED LOW OFFSHORE OF
THE SOUTHERN CALIFORNIA/NORTHERN BAJA PACIFIC COAST. IT IS BECOMING
MORE CERTAIN THAT THE CYCLONIC CIRCULATION AND COLDER TEMPERATURES
ASSOCIATED WITH AN ELONGATING MID-LEVEL COLD CORE WILL GENERALLY
REMAIN OFFSHORE OF THE SOUTHERN CALIFORNIA, BEFORE TURNING INLAND
ACROSS NORTHERN BAJA AFTER 12Z FRIDAY.
..SOUTHERN CALIFORNIA
MODELS CONTINUE TO INDICATE COLDEST OFFSHORE MID-LEVEL TEMPERATURES
AT A SOMEWHAT MODEST -22 TO -24C AROUND 500 MB. HOWEVER, BASED ON
THE LATEST RAPID REFRESH AND NAM FORECAST SOUNDINGS, WEAK
DESTABILIZATION SUPPORTIVE OF SHORT-LIVED WEAK THUNDERSTORM
DEVELOPMENT MAY NOT BE ENTIRELY OUT OF THE QUESTION NEAR COASTAL
AREAS, PARTICULARLY WHERE FORCING FOR ASCENT IS AIDED BY OROGRAPHY
NEAR THE TRANSVERSE AND PERHAPS PENINSULAR RANGES. CERTAINTY DOES
NOT YET APPEAR HIGH ENOUGH FOR THE MINIMUM 10 PERCENT THRESHOLD, BUT
THIS WILL CONTINUE TO BE MONITORED.
..GULF COAST STATES
GIVEN THE GENERAL TENDENCY FOR WARMING MID-LEVELS, AND THE LACK OF
BOTH MORE SUBSTANTIVE FURTHER LOW-LEVEL MOISTENING OFF A SLOWLY
MODIFYING GULF BOUNDARY LAYER AND MID/UPPER SUPPORT FOR ASCENT, THE
RISK FOR THUNDERSTORM ACTIVITY STILL APPEARS MINIMAL THURSDAY
THROUGH THURSDAY NIGHT. THE PRIMARY EXCEPTION STILL APPEARS NEAR
SOUTHEASTERN FLORIDA COASTAL AREAS, IN RESPONSE TO INCREASING
BOUNDARY-LAYER DESTABILIZATION AND CONVERGENCE, NEAR DEVELOPING
SURFACE TROUGHING AND THE REMNANT SURFACE FRONT, PERHAPS AIDED BY
FORCING ASSOCIATED WITH WEAK PERTURBATIONS WITHIN THE SUBTROPICAL
WESTERLIES.
..KERR.. 01/21/2026
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