390
ACUS02 KWNS 150525
SWODY2
SPC AC 150523
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1223 AM CDT THU OCT 15 2026
VALID 161200Z - 171200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF
THE MID-ATLANTIC...
..SUMMARY
SCATTERED SEVERE STORMS CAPABLE OF DAMAGING WIND GUSTS AND PERHAPS A
BRIEF TORNADO OR TWO ARE POSSIBLE IN PARTS OF THE MID-ATLANTIC
FRIDAY AFTERNOON AND EVENING.
..SYNOPSIS
THE MODELS CONTINUE TO SLOW THE PROGRESSION OF AN INTENSE MIDLEVEL
TROUGH, WHICH WILL TRACK THROUGH THE MISSISSIPPI VALLEY AND GREAT
LAKES TOWARD THE APPALACHIANS BY EARLY SATURDAY. AN ATTENDING BELT
OF STRONG, SOUTHWESTERLY MID/UPPER-LEVEL FLOW (E.G., 70-90 KT AT 500
MB) WILL PRECEDE THE TROUGH, THE EASTERN EDGE OF WHICH WILL
OVERSPREAD THE MID-ATLANTIC ON SATURDAY. IN THE LOW LEVELS, A
SURFACE CYCLONE WILL DEVELOP FROM THE LOWER GREAT LAKES INTO THE
GULF OF ST. LAWRENCE, WHILE A TRAILING COLD FRONT ADVANCES FROM THE
LOWER GREAT LAKES/UPPER-OHIO VALLEY REGIONS FRIDAY MORNING TO OFF
THE MID-ATLANTIC COAST BY FRIDAY NIGHT.
..MID-ATLANTIC
SHOWERS AND THUNDERSTORMS MAY BE ONGOING AT 12Z FRIDAY FROM NORTHERN
PA AND NY INTO NEW ENGLAND, WITH LINGERING CLOUDS AND DECREASING
BOUNDARY-LAYER MOISTURE WITH NORTHWARD EXTENT LIMITING AIR MASS
DESTABILIZATION IN THE VICINITY OF THE SURFACE LOW. FARTHER SOUTH
AHEAD OF THE COLD FRONT, GREATER DIABATIC HEATING WILL COMBINE WITH
DEWPOINTS IN THE 60S TO AROUND 70 F TO YIELD MLCAPE APPROACHING
500-750 J/KG BY MID AFTERNOON. OVERALL CAPE DEPTH AND MAGNITUDE WILL
BE LIMITED BY WARM TEMPERATURES ALOFT ON THE ANTICYCLONIC SIDE OF
THE UPPER-LEVEL JET STREAK.
RENEWED THUNDERSTORM DEVELOPMENT IS ANTICIPATED BY LATE MORNING OR
EARLY AFTERNOON ALONG THE FRONT OVER EASTERN OH AND WV INTO WESTERN
PARTS OF PA AND NY. AN INCREASE IN STORM COVERAGE AND INTENSITY IS
EXPECTED THROUGH THE REMAINDER OF THE AFTERNOON AS THE FRONT
ENCOUNTERS A MORE UNSTABLE AIR MASS WITH EASTWARD EXTENT. VERTICAL
SHEAR WILL BE STRONG WITH EFFECTIVE BULK SHEAR MAGNITUDES OF 45-55
KT, SUGGESTING THE POTENTIAL FOR EMBEDDED SUPERCELLS AND/OR BOWING
STRUCTURES WITHIN THE LINE. DAMAGING WIND GUSTS WILL BE THE PRIMARY
HAZARD, THOUGH A BRIEF TORNADO OR TWO APPEAR POSSIBLE IN THE
DELAWARE RIVER VALLEY AND DELMARVA, WHERE LOCALLY STRONGER LOW-LEVEL
SHEAR IS FORECAST DURING THE LATE AFTERNOON INTO EARLY EVENING.
AN UPGRADE TO LEVEL-2/SLIGHT RISK HAS BEEN INCLUDED WITH THIS
FORECAST UPDATE TO HIGHLIGHT THE AREA WHERE THE MOST FAVORABLE
OVERLAP OF INSTABILITY AND VERTICAL SHEAR IS FORECAST FROM MID
AFTERNOON INTO EARLY EVENING.
..MEAD.. 10/15/2026
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