462
ACUS02 KWNS 100503
SWODY2
SPC AC 100502
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1202 AM CDT SAT MAY 10 2025
VALID 111200Z - 121200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY INTO
SUNDAY NIGHT ACROSS PARTS OF CNTRL AND NRN FL...SRN SC...SRN
GA......SRN/WRN AL...CNTRL/ERN MS...CNTRL/ERN MT...WRN ND...
..SUMMARY
WIDELY SCATTERED STRONG THUNDERSTORMS MAY IMPACT THE EASTERN GULF
COAST STATES ON SUNDAY, POSING AT LEAST SOME RISK FOR SEVERE HAIL
AND LOCALLY STRONG SURFACE GUSTS. ADDITIONAL THUNDERSTORMS MAY BE
ACCOMPANIED BY SOME RISK FOR SEVERE HAIL AND STRONG TO SEVERE WIND
GUSTS ACROSS PARTS OF CENTRAL AND EASTERN MONTANA INTO WESTERN NORTH
DAKOTA LATE SUNDAY AFTERNOON AND EVENING.
..SYNOPSIS
MODELS CONTINUE TO INDICATE LITTLE CHANGE TO THE GENERAL LARGE-SCALE
PATTERN THROUGH THIS PERIOD, WITH MUCH OF NORTH AMERICA REMAINING
UNDER THE INFLUENCE OF AMPLIFIED, SPLIT WESTERLIES - STRONGER ACROSS
THE NORTHERN MID-LATITUDES THAN ACROSS THE SOUTHERN MID- AND
SUBTROPICAL LATITUDES. WITHIN THIS REGIME, SIGNIFICANT MID-LEVEL
TROUGHING, WITH AT LEAST A COUPLE OF SMALLER-SCALE EMBEDDED
PERTURBATIONS, IS FORECAST TO BEGIN DIGGING INLAND OF THE NORTHERN
U.S. PACIFIC COAST. AS THIS OCCURS, BROAD DOWNSTREAM RIDGING WILL
CONTINUE SLOWLY EASTWARD ACROSS THE INTERIOR OF NORTH AMERICA, WITH
THE LEADING EDGE LIKELY AS FAR EAST AS THE ST. LAWRENCE VALLEY AND
NORTHEAST BY LATE SUNDAY NIGHT. TO THE SOUTH OF THIS RIDGE, THE
CENTER OF A BROAD, INITIALLY QUASI-STATIONARY MID-LEVEL LOW MAY
BEGIN A VERY SLOW ACCELERATION BACK TO THE NORTHEAST, ACROSS THE
LOWER MISSISSIPPI VALLEY, IN RESPONSE TO THE TROUGHING DIGGING INTO
THE NORTHWEST.
IN LOWER LEVELS, IT APPEARS THAT ONE INITIAL WEAK LOW ACROSS THE
CANADIAN PRAIRIES WILL WEAKEN FURTHER, AS SURFACE TROUGHING
DEEPENS UPSTREAM, TO THE LEE OF THE CANADIAN AND NORTHERN U.S.
ROCKIES. AT THE SAME TIME, COOL SURFACE RIDGING, INITIALLY CENTERED
ACROSS THE LOWER GREAT LAKES VICINITY, IS LIKELY TO REDEVELOP
SOUTHEASTWARD OFF THE NORTHERN MID ATLANTIC COAST. NEAR THE
SOUTHWESTERN PERIPHERY OF THIS RIDGE, A BROAD AREA OF LOWER SURFACE
PRESSURE MAY CONTINUE DEVELOPING INLAND OF THE NORTH CENTRAL GULF
COAST, PERHAPS ACCOMPANIED BY SOME FURTHER BOUNDARY-LAYER MOISTENING
INLAND ACROSS PARTS OF THE EASTERN GULF STATES. SEASONABLY HIGH
MOISTURE CONTENT, THOUGH, MAY REMAIN CONFINED TO A NARROW PLUME
SOUTHEAST THROUGH SOUTH OF THE MID-LEVEL LOW, FROM SOUTH CAROLINA
AND GEORGIA COASTAL AREAS ACROSS THE FLORIDA PENINSULA INTO THE
LOWER LATITUDES.
..LOWER MISSISSIPPI VALLEY/EASTERN GULF COAST STATES
BENEATH THE MODEST, DIFLUENT SOUTHWESTERLY FLOW, DOWNSTREAM OF THE
MID/UPPER LOW, MODEL FORECAST SOUNDINGS CONTINUE TO SUGGEST THAT
THERMODYNAMIC PROFILES COULD BECOME CONDUCIVE TO WIDELY SCATTERED
STRONG THUNDERSTORMS WITH POTENTIAL TO PRODUCE SEVERE HAIL AND
LOCALLY STRONG SURFACE GUSTS BY SUNDAY AFTERNOON. JUST EAST OF THE
BROAD, WEAK SURFACE LOW CENTERED OVER THE LOWER MISSISSIPPI VALLEY,
A BELT OF MODEST SOUTHERLY 850 MB FLOW MAY CONTRIBUTE TO LOW-LEVEL
HODOGRAPHS WHICH MAY BECOME MARGINALLY CONDUCIVE TO A TORNADO OR
TWO.
..NORTH ROCKIES INTO ADJACENT GREAT PLAINS
DOWNSTREAM OF THE LARGE-SCALE MID/UPPER TROUGHING DIGGING INTO THE
NORTHWEST, IT APPEARS THAT FORCING FOR ASCENT IN THE PRESENCE OF
WEAK DESTABILIZATION WILL BECOME SUFFICIENT FOR AT LEAST SCATTERED
THUNDERSTORM DEVELOPMENT. IT APPEARS THAT THERMODYNAMIC PROFILES,
IN THE PRESENCE OF STRONG DEEP-LAYER SHEAR, MAY BECOME CONDUCIVE TO
STORMS WITH AT LEAST SOME POTENTIAL TO PRODUCE SEVERE HAIL ACROSS
THE HIGHER TERRAIN OF CENTRAL MONTANA.
AS CONVECTION PROPAGATES NORTHEASTWARD OFF THE HIGHER TERRAIN OF
CENTRAL AND SOUTHERN MONTANA, ACROSS A MORE STRONGLY HEATED AND
DEEPLY MIXED BOUNDARY LAYER, DOWNDRAFTS ENHANCED BY EVAPORATIVE
COOLING/MELTING AND DOWNWARD MIXING OF STRONGER FLOW FROM ALOFT
PROBABLY WILL CONTRIBUTE TO A FEW STRONG TO SEVERE SURFACE GUSTS.
THE LATEST NAM CONTINUES TO SUGGEST POTENTIAL FOR ONE OR TWO
CLUSTERS WITH CONSOLIDATING DOWNDRAFTS AND OUTFLOW, THOUGH NOW
GENERALLY ACROSS PARTS OF CENTRAL/EASTERN MONTANA AND, PERHAPS, INTO
WESTERN NORTH DAKOTA BY LATE SUNDAY EVENING.
..KERR.. 05/10/2025
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page