827
ACUS01 KWNS 011249
SWODY1
SPC AC 011247
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0747 AM CDT TUE JUL 01 2025
VALID 011300Z - 021200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
MID-ATLANTIC REGION AND ACROSS WESTERN PORTIONS OF NEBRASKA AND
SOUTH DAKOTA...
..SUMMARY
SCATTERED STRONG TO SEVERE STORMS ARE POSSIBLE ACROSS PARTS OF THE
MID-ATLANTIC INTO THE NORTHEAST THIS AFTERNOON/EVENING. A FEW
SEVERE THUNDERSTORMS ARE POSSIBLE OVER WESTERN PARTS OF NEBRASKA AND
SOUTH DAKOTA.
..MID-ATLANTIC STATES INTO THE NORTHEAST AND SOUTHEAST
WATER-VAPOR IMAGERY THIS MORNING INDICATES AN UPPER TROUGH IS MOVING
EAST ACROSS THE GREAT LAKES/LOWER OH VALLEY AND OTHER MINOR
PERTURBATIONS ARE LOCATED OVER THE MID SOUTH. THE PRIMARY
DISTURBANCE WILL OVERSPREAD THE APPALACHIANS BY MID-LATE EVENING.
IN THE LOW LEVELS, A COLD FRONT ANALYZED OVER THE SOUTHERN GREAT
LAKES INTO THE LOWER OH VALLEY/MID SOUTH WILL GRADUALLY PROGRESS
EAST/SOUTHEAST DURING THE PERIOD.
12 UTC RAOB DATA FROM THE OH VALLEY AND MID SOUTH EASTWARD TO THE
MID-ATLANTIC REGION SHOWS A VERY MOIST TROPOSPHERE WITH LIMITED
700-500 MB LAPSE RATES (LESS THAN 5.5 DEG C/KM). NONETHELESS,
DIURNAL HEATING OF THE MOIST BOUNDARY LAYER WILL RESULT IN MODERATE
BUOYANCY FROM PORTIONS OF THE NORTHEAST SOUTHWESTWARD THROUGH THE
MID-ATLANTIC STATES AND INTO THE SOUTHEAST. MODELS CONTINUE TO
INDICATE MODEST SOUTHWESTERLY MID-LEVEL FLOW ACROSS THE MID-ATLANTIC
STATES WILL CONTRIBUTE TO ADEQUATE SHEAR, SUPPORTING SOME
ORGANIZATION OF STORMS INTO LINE SEGMENTS/CLUSTERS. SCATTERED
THUNDERSTORMS WILL INCREASE IN COVERAGE WITH TIME AND NUMEROUS
THUNDERSTORMS ARE EXPECTED BY MID-LATE AFTERNOON WHILE MOVING EAST
ACROSS PA/WV/VA/MD. STRONG TO SEVERE GUSTS (50-65 MPH) ARE POSSIBLE
WITH THE STRONGER DOWNDRAFTS. LESS ORGANIZED BUT SCATTERED TO
NUMEROUS STORMS ARE FORECAST FARTHER SOUTHWEST INTO PORTIONS OF THE
SOUTHERN APPALACHIANS WITH A RISK FOR DAMAGING GUSTS WITH THE
STRONGER STORMS. STRONG-SEVERE CONVECTION SHOULD SPREAD OFF THE
MIDDLE ATLANTIC COAST DURING THE EVENING.
..BLACK HILLS INTO THE CENTRAL HIGH PLAINS
A WEAK MID-LEVEL DISTURBANCE IS MOVING EAST ACROSS NORTHERN
WY/SOUTHERN MT TOWARDS THE SD/NE VICINITY LATER TODAY. A WEAK LEE
TROUGH WILL LIKELY SERVE AS A FOCUS FOR THUNDERSTORM DEVELOPMENT
THIS AFTERNOON FROM NEAR THE BLACK HILLS SOUTHWARD INTO NORTHEAST
CO. FORECAST SOUNDINGS SHOW AROUND 30-KT EFFECTIVE SHEAR IN THE
PRESENCE OF STEEP LAPSE RATES AND MODERATE MLCAPE (1000-2500 J/KG).
SOME OF THE RECENT MPAS GUIDANCE INDICATES A FEW STRONGER
THUNDERSTORMS WILL DEVELOP ACROSS WESTERN NE AND PERHAPS INTO
WESTERN SD. A COUPLE OF SUPERCELLS WITH AN ATTENDANT LARGE-HAIL
RISK ARE POSSIBLE, THEREBY PROMPTING AN INCREASE IN HAIL
PROBABILITIES THIS OUTLOOK UPDATE. SOME SEVERE RISK MAY LINGER INTO
THE MID-LATE EVENING COINCIDENT WITH A STRENGTHENING OF A SOUTHERLY
LLJ CENTERED OVER WEST-CENTRAL NE BEFORE THIS ACTIVITY DISSIPATES.
..SMITH/BROYLES.. 07/01/2025
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