514
ACUS01 KWNS 160558
SWODY1
SPC AC 160556
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1256 AM CDT FRI OCT 16 2026
VALID 161200Z - 171200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
MID-ATLANTIC INTO SOUTHERN NEW ENGLAND...
..SUMMARY
THUNDERSTORMS WITH WIND-DAMAGE AND LOCALIZED BRIEF-TORNADO POTENTIAL
ARE EXPECTED ACROSS PARTS OF THE MID-ATLANTIC INTO SOUTHERN NEW
ENGLAND, MAINLY THIS AFTERNOON AND EARLY EVENING.
..MID-ATLANTIC INTO SOUTHERN NEW ENGLAND
A DEEP, POSITIVE-TILT MID/UPPER-LEVEL TROUGH IS FORECAST TO FURTHER
AMPLIFY AS IT SPREADS OVER THE EASTERN CONUS TODAY. A SURFACE LOW
INITIALLY NEAR THE LOWER GREAT LAKES WILL MOVE QUICKLY EASTWARD
TOWARD NORTHERN NEW ENGLAND BY EVENING. A TRAILING COLD FRONT WILL
SWEEP THROUGH THE MID-ATLANTIC AND NORTHEAST FROM THIS AFTERNOON
INTO TONIGHT.
IN THE WAKE OF EARLY-DAY CLOUDS AND PRECIPITATION, SEASONABLY RICH
LOW-LEVEL MOISTURE AND MODEST DIURNAL HEATING WILL RESULT IN
SUFFICIENT DESTABILIZATION FOR STORM DEVELOPMENT ALONG THE FRONT.
VERY WEAK LAPSE RATES ABOVE 500 MB WILL CONSTRAIN MLCAPE MAGNITUDES
TO THE 500-1000 J/KG RANGE, AND RESULT IN RATHER LOW-TOPPED
CONVECTION. HOWEVER, IN AREAS WHERE TEMPERATURES CAN RISE TO
NEAR/ABOVE 70 F, RELATIVELY ROBUST BUOYANCY NEAR/BELOW 500 MB
(CHARACTERIZED BY LIFTED INDICES IN THE -4 TO -6 C RANGE) WILL
DEVELOP PRIOR TO THE FRONTAL PASSAGE. THIS BUOYANCY WILL BE
SUFFICIENT FOR DEVELOPMENT OF OCCASIONALLY ORGANIZED STORM
STRUCTURES, IN THE PRESENCE OF STRENGTHENING DEEP-LAYER FLOW/SHEAR.
35-45 KT OF FLOW IN THE 1-2 KM AGL LAYER WILL SUPPORT POTENTIAL FOR
STRONG/DAMAGING GUSTS WITH ANY SUFFICIENTLY ROBUST CONVECTION.
GENERALLY FRONT-PARALLEL FLOW MAY RESULT IN A PRIMARILY LINEAR MODE
AS CONVECTIVE COVERAGE INCREASES, THOUGH 40+ KT OF EFFECTIVE SHEAR
WILL SUPPORT POTENTIAL FOR EMBEDDED LOW-TOPPED SUPERCELLS. A
LOCALIZED WIND-DAMAGE THREAT MAY DEVELOP EARLY THIS AFTERNOON FROM
WV/WESTERN PA INTO SOUTHERN NY, WITH INITIAL FRONTAL DEVELOPMENT.
THE WIND-DAMAGE THREAT IS EXPECTED TO INCREASE THROUGH THE AFTERNOON
AS STORMS SPREAD EASTWARD INTO A SOMEWHAT WARMER AND MORE UNSTABLE
ENVIRONMENT ACROSS EASTERN PA, NJ, AND VICINITY. RATHER STRONG
LOW-LEVEL SHEAR WILL ALSO SUPPORT SOME BRIEF-TORNADO POTENTIAL WITH
QLCS CIRCULATIONS AND/OR EMBEDDED SUPERCELL STRUCTURES.
SOME WIND-DAMAGE POTENTIAL COULD SPREAD INTO SOUTHERN NEW ENGLAND BY
THIS EVENING, THOUGH MARINE-INFLUENCED LOW-LEVEL STABILITY SHOULD
EVENTUALLY CONSTRAIN THE EASTWARD EXTENT OF THE THREAT.
..DEAN/CHALMERS.. 10/16/2026
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