427
ACUS02 KWNS 291730
SWODY2
SPC AC 291728
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1228 PM CDT WED MAR 29 2023
VALID 301200Z - 311200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE SOUTHERN/CENTRAL PLAINS AND THE UPPER MIDWEST...
..SUMMARY
ISOLATED STRONG TO SEVERE STORMS ARE POSSIBLE OVER PARTS OF THE
SOUTHERN AND CENTRAL PLAINS THURSDAY EVENING AND OVERNIGHT.
..SYNOPSIS
AMPLIFIED MID-LEVEL FLOW IS EXPECTED ACROSS MUCH OF THE CONUS AS AN
ACTIVE FLOW REGIME CONTINUES. AN ANOMALOUSLY DEEP UPPER-LEVEL
CYCLONE OVER THE WEST COAST IS FORECAST TO SHIFT EASTWARD ACROSS THE
SOUTHWEST AS IT TRANSITIONS TOWARD AN OPEN WAVE THROUGH THURSDAY. A
LEE CYCLONE OVER EASTERN CO SHOULD DEEPEN AS LIFT FROM THE TROUGH
AND AN 80-90 KT JET STREAK OVERSPREADS THE SOUTHERN/CENTRAL ROCKIES
AND HIGH PLAINS. TO THE EAST, SHORTWAVE RIDGING OVER THE SOUTHEAST
WILL SUPPORT BROAD SOUTHERLY RETURN FLOW ACROSS THE CENTER OF THE
COUNTRY. A WARM FRONT WILL RAPIDLY LIFT POLEWARD EXTENDING INTO
KS/NE BY THE END OF THE PERIOD. WEAK DESTABILIZATION AND STRONG
SHEAR NEAR AND SOUTH OF THE FRONT MAY SUPPORT ISOLATED SEVERE
THUNDERSTORMS AHEAD OF THE DEEPENING SURFACE CYCLONE ACROSS THE
CENTRAL AND SOUTHERN GREAT PLAINS THURSDAY EVENING INTO THE
OVERNIGHT HOURS.
..SOUTHERN PLAINS
AS THE UPPER TROUGH BEGINS TO EJECT EASTWARD OUT OF THE SOUTHWEST
OVER THE ROCKIES AND HIGH PLAINS, LARGE-SCALE ASCENT FROM THE
ADVANCING POLAR JET STREAK/TROUGH IS FORECAST TO GENERALLY LAG
BEHIND THE RETURNING WARM SECTOR FARTHER EAST. DESPITE RAPID
NORTHWARD ADVECTION OF UPPER 50S TO LOW 60S F SURFACE DEWPOINTS,
PERHAPS AS FAR NORTH AS KS/OK BY 00Z, CONSIDERABLE INHIBITION IS
EXPECTED DURING THE DAYLIGHT HOURS ACROSS MUCH OF THE SOUTHERN
PLAINS. THIS SHOULD GENERALLY SUPPRESS SURFACE BASED THUNDERSTORMS
UNTIL AFTER SUNSET, THOUGH A CONDITIONAL RISK FOR A SUPERCELL WILL
REMAIN POSSIBLE PRIMARILY ACROSS SOUTHWESTERN OK. A FEW ELEVATED
CELLS MAY DEVELOP WITH A SMALL SOUTHERN STREAM PERTURBATION PASSING
OVER PORTIONS OF EASTERN OK WITH A RISK FOR HAIL AND OR WIND.
GRADUALLY INCREASING FORCING FOR ASCENT AHEAD OF THE ADVANCING
PACIFIC FRONT/DRYLINE MAY ALLOW FOR ISOLATED THUNDERSTORMS TO
DEVELOP NEAR THE RED RIVER IN SOUTH-CENTRAL/SOUTHEASTERN OK AND
TRACK EAST NORTHEASTWARD OVERNIGHT. WHILE LIKELY SOMEWHAT STABLE IN
THE LOW LEVELS, INCREASING VERTICAL SHEAR SUPPORTIVE OF ORGANIZED
STORMS, INCLUDING SUPERCELLS, MAY PROMOTE A RISK FOR ISOLATED HAIL
AND DAMAGING GUSTS.
..CENTRAL PLAINS AND MIDWEST
FARTHER NORTH, LARGE-SCALE FORCING WILL ARRIVE EARLIER IN THE
DIURNAL CYCLE ACROSS PORTIONS OF EASTERN NE/SD INTO THE UPPER
MIDWEST, BUT THE LOW-LEVELS WILL REMAIN MOSTLY STABLE AT THE TIP OF
THE MOIST PLUME RAPIDLY ADVECTING NORTH. AS A RESULT, LIMITED
BUOYANCY (GENERALLY LESS THAN 500 J/KG OF MUCAPE) IS EXPECTED
DESPITE STEEPER MID-LEVEL LAPSE RATES BENEATH THE COLD CORE OF THE
TROUGH. ISOLATED ELEVATED THUNDERSTORMS MAY DEVELOP LATE IN THE
AFTERNOON FROM EASTERN NE INTO SOUTHERN SD CAPABLE OF SOME SEVERE
HAIL GIVEN FAVORABLE SHEAR PROFILES FOR SUPERCELLS.
AS THE MAIN TROUGH CONTINUES EASTWARD, LOW-LEVEL MASS RESPONSE FROM
THE DEEPENING SURFACE LOW SHOULD ALLOW FOR MORE WIDESPREAD
THUNDERSTORMS TO DEVELOP AFTER DARK. ELEVATED THUNDERSTORMS SHOULD
DEVELOP IN AN ARC NEAR THE CORE OF THE LOW-LEVEL JET FROM WESTERN
IA, TOWARD SOUTHWESTERN MN. SEVERE HAIL MAY DEVELOP NORTH OF THE
WARM FRONT THROUGH THE OVERNIGHT AND INTO EARLY FRIDAY MORNING.
ADDITIONAL ELEVATED THUNDERSTORMS ARE POSSIBLE FARTHER EAST OVER
PORTIONS OF NORTHERN AND CENTRAL IL, BUT CONFIDENCE IN SEVERE
POTENTIAL HERE IS LOWER OWING TO WEAKER FORCING AND MORE LIMITED
LAPSE RATES ALOFT.
..LYONS/JEWELL.. 03/29/2023
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page