129
ACUS02 KWNS 050557
SWODY2
SPC AC 050555
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1255 AM CDT SAT JUL 05 2025
VALID 061200Z - 071200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE CENTRAL HIGH PLAINS...
..SUMMARY
STORMS MAY PRODUCE SEVERE WIND AND HAIL ALONG THE CENTRAL HIGH
PLAINS TOMORROW (SUNDAY). A FEW INSTANCES OF 2+ INCH DIAMETER HAIL
AND 75+ MPH WIND GUSTS ARE POSSIBLE.
..SYNOPSIS
MAINLY ZONAL UPPER FLOW WILL BECOME ESTABLISHED OVER THE NORTHERN
CONUS, WITH MULTIPLE EMBEDDED IMPULSES POISED TO TRAVERSE THE ZONAL
FLOW THROUGH THE DAY TOMORROW (SUNDAY). THE BEST CHANCE FOR STRONG
STORMS WILL BE ASSOCIATED WITH MID-LEVEL IMPULSES IMPINGING ON THE
HIGH PLAINS AND NEW ENGLAND SUNDAY AFTERNOON. AMPLE MOISTURE AND
ASSOCIATED INSTABILITY WILL PRECEDE THE IMPULSES, THAT COMBINED WITH
ADEQUATE VERTICAL WIND SHEAR, WILL SUPPORT STORM ORGANIZATION, SOME
OF WHICH COULD BE SEVERE.
..MAINE
A BELT OF 50 KT WESTERLY 500 MB FLOW WILL OVERSPREAD SOUTHEAST
QUEBEC INTO MAINE SUNDAY AFTERNOON WITH THE OVERHEAD PASSAGE OF A
MID-LEVEL IMPULSE. SURFACE LEE TROUGHING OVER MAINE WILL SERVE AS AN
IMPETUS FOR THUNDERSTORM INITIATION DURING THE AFTERNOON, WHEN
SURFACE TEMPERATURES/DEWPOINTS IN THE LOW 80S/UPPER 60S F WILL BOOST
MLCAPE TO OVER 1000 J/KG. MODESTLY CURVED, SIZEABLE LOW-LEVEL
HODOGRAPHS SUGGEST THAT MULTICELLS AND SUPERCELLS WILL BE THE MAIN
STORM MODE, POSSIBLY ACCOMPANIED BY DAMAGING GUSTS.
..CENTRAL AND SOUTHERN HIGH PLAINS
LOW-LEVEL UPSLOPE FLOW WILL ENCOURAGE THE NORTHWESTWARD ADVECTION OF
60S F SURFACE DEWPOINTS INTO THE HIGHER TERRAIN OF THE HIGH PLAINS
SUNDAY AFTERNOON, BENEATH 8-9 C/KM 700-500 MB LAPSE RATES. MODERATE
TO STRONG INSTABILITY WILL MANIFEST, WITH OVER 3000 J/KG MLCAPE
POSSIBLE. STORMS WILL INITIATE OVER THE HIGHER TERRAIN, AMID
STRAIGHT HODOGRAPHS, CONTRIBUTING TO SPLITTING SUPERCELL POTENTIAL.
BY EVENING, THE SOUTHEASTERLY SURFACE FLOW WILL BE OVERSPREAD BY A
STRENGTHENING SOUTHERLY LOW-LEVEL JET, WITH FLOW QUICKLY VEERING TO
WESTERLY IN THE 700-500 MB LAYER. THIS DIRECTIONAL SHEAR WILL
SUPPORT CURVED LOW-LEVEL HODOGRAPHS WITH CONTINUED SUPERCELL
POTENTIAL, BEFORE STORMS MERGE INTO AN MCS BY EVENING. WHILE IN THE
SUPERCELL PHASE, A FEW INSTANCES OF SEVERE HAIL (PERHAPS AN INSTANCE
OR TWO OF 2+ INCH DIAMETER HAIL) ARE POSSIBLE, ALONG WITH SEVERE
GUSTS AND PERHAPS A TORNADO. BY THE TIME STORMS MERGE INTO AN MCS,
SEVERE GUSTS WILL BECOME THE PRIMARY THREAT, AND A FEW GUSTS
EXCEEDING 75 MPH WILL BE POSSIBLE. HIGHER SEVERE PROBABILITIES MAY
BE NEEDED IF CONFIDENCE INCREASES IN A LONGER-LIVED, SEVERE-WIND
PRODUCING MCS DEVELOPING.
FARTHER SOUTH INTO THE SOUTHERN HIGH PLAINS, STORM COVERAGE SHOULD
BE RELATIVELY LESS, WITH MULTICELLS BECOMING OUTFLOW DOMINANT MORE
QUICKLY GIVEN WEAKER VERTICAL WIND SHEAR COMPARED TO THE CENTRAL
HIGH PLAINS. NONETHELESS, AN INSTANCE OR TWO OF HAIL IS POSSIBLE,
ALONG WITH SEVERE GUSTS, ESPECIALLY WITH MULTICELLULAR COLD-POOL
MERGERS.
..COASTAL CAROLINAS
A TROPICAL STORM IS FORECAST TO MAKE LANDFALL ALONG THE CAROLINA
COASTLINE AT THE START OF THE DAY 2 PERIOD/12Z SUNDAY (PLEASE SEE
THE NATIONAL HURRICANE CENTER'S ADVISORIES FOR MORE INFORMATION ON
THE PROGRESSION OF TROPICAL DEPRESSION 3). A DEEPLY MOIST
TROPOSPHERE WILL ACCOMPANY THE LAND-FALLING TC, WITH MLCAPE
APPROACHING THE 750-1000 J/KG RANGE. NONETHELESS, THE VERTICAL WIND
FIELDS ASSOCIATED WITH THIS LAND-FALLING TROPICAL STORM ARE EXPECTED
TO QUICKLY WEAKEN, ALONG WITH VERTICAL WIND SHEAR. AS SUCH, WHILE
THE RISK FOR A BRIEF TORNADO IS TECHNICALLY NON-ZERO, CONFIDENCE IN
ANY ROBUST TORNADO COVERAGE IS TOO LOW FOR THE INTRODUCTION OF 2
PERCENT OR GREATER TORNADO PROBABILITIES AT THIS TIME.
..SQUITIERI.. 07/05/2025
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page