Severe Storm Outlook Narrative (AC)
Issued by NWS

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000
ACUS02 KWNS 270559
SWODY2
SPC AC 270558

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1258 AM CDT WED JUL 27 2016

VALID 281200Z - 291200Z

...THERE IS A SLGT RISK OF SVR TSTMS FOR PARTS OF SERN WY...WRN
NEB...NERN CO...WRN KS...

...THERE IS A SLGT RISK OF SVR TSTMS FOR PARTS OF SERN VA AND NERN
NC...

...THERE IS A MRGL RISK OF SVR TSTMS FOR THE CNTRL AND NRN PLAINS...

...THERE IS A MRGL RISK OF SVR TSTMS FOR THE MID-ATLANTIC REGION
INTO THE SRN/CNTRL APPALACHIANS...

...SUMMARY...
ISOLATED TO SCATTERED SEVERE THUNDERSTORMS WILL BE POSSIBLE ACROSS
PARTS OF THE CENTRAL PLAINS AND MID-ATLANTIC REGION. OTHER STRONG
STORMS ARE POSSIBLE OVER THE NORTHERN HIGH PLAINS...AND THE SOUTHERN
AND CENTRAL APPALACHIANS.

...SYNOPSIS...
BELT OF MODERATE WLY FLOW WILL EXTEND FROM THE PAC NW EWD ACROSS THE
NRN/CNTRL PLAINS TO THE MID-ATLANTIC REGION...ALONG THE NRN
PERIPHERY OF A PAIR OF MIDLEVEL ANTICYCLONES CENTERED OVER THE GREAT
BASIN AND OFF CAROLINA COAST. A SHORTWAVE IMPULSE INITIALLY OVER THE
NRN ROCKIES WILL MOVE SEWD ACROSS THE NRN/CNTRL HIGH PLAINS DURING
THE AFTERNOON. A SECOND IMPULSE WILL MOVE ACROSS THE MID-SOUTH INTO
THE CNTRL APPALACHIANS. A WEAK SFC FRONT WILL EXTEND FROM SRN NEW
ENGLAND ACROSS THE OH VALLEY...WHILE A SEPARATE COLD FRONT WILL MOVE
SWD ACROSS THE DAKOTAS INTO THE CNTRL PLAINS.

...NRN/CNTRL PLAINS...
A SHORTWAVE IMPULSE IS FORECAST TO MOVE OUT OF THE NRN ROCKIES AND
OVER THE NRN/CNTRL PLAINS DURING THE AFTERNOON...AND CONVECTION MAY
BE ONGOING ACROSS PARTS OF ERN MT/WY AND THE WRN DAKOTAS AT THE
START OF THE PERIOD. A CORRIDOR OF MID-50S TO LOW-60S F DEWPOINTS
SHOULD BECOME ESTABLISHED FROM CNTRL KS ACROSS THE HIGH PLAINS
WITHIN AN UPSLOPE REGIME. NWRN SEGMENT OF COLD FRONT IS EXPECTED TO
STALL OVER WRN ND OR ERN MT...WHILE REMAINDER OF THE FRONT SLOWLY
ADVANCES SWD ACROSS SD INTO NRN NEB. THIS FRONT IS EXPECTED TO
DELINEATE THE ERN PORTION OF THE MOST UNSTABLE AIR MASS...AND EARLY
CONVECTION ACROSS THE NRN HIGH PLAINS MAY PERSIST AND INTENSIFY
WHILE MOVING SEWD INTO WRN SD AND ERN WY DURING THE LATE MORNING AND
AFTERNOON.

THE MOST UNSTABLE AIR MASS WILL BE IN PLACE E OF THE FRONT RANGE
ACROSS SERN WY INTO NERN CO AND SWRN NEB...WHERE STRONG HEATING
SHOULD ENCOURAGE TSTM INITIATION DURING THE AFTERNOON. MODERATE TO
STRONG DEEP-LAYER SHEAR COMBINED WITH STEEP TROPOSPHERIC LAPSE RATES
SHOULD SUPPORT A FEW SUPERCELLS INITIALLY...WITH LARGE HAIL...DMGG
WINDS...AND A TORNADO ALL POSSIBLE. STRENGTHENING OF THE NOCTURNAL
LLJ FROM THE TX PANHANDLE INTO WRN KS MAY EVENTUALLY SUPPORT UPSCALE
GROWTH INTO A SEWD MOVING MCS THU EVENING...PERHAPS REACHING S-CNTRL
KS AND NRN OK BY THE END OF THE D2 PERIOD.

...SRN/CNTRL APPALACHIANS AND THE MID-ATLANTIC REGION...
A MOIST AIR MASS WILL BE IN PLACE /PW VALUES OVER 2 INCHES/ AS
30-40 KT OF SWLY MIDLEVEL FLOW OVERSPREADS THE REGION. WEAK SFC LOW
IS FORECAST TO DEVELOP ACROSS NC...WITH A BOUNDARY EXTENDING NWD
ACROSS CNTRL VA...WHILE STALLED SYNOPTIC FRONT IS POSITIONED NEAR
THE MD/PA BORDER. A SERIES OF WEAK IMPULSES IS EXPECTED TO EJECT
NEWD DURING THE DAY...AHEAD OF PRIMARY SHORTWAVE TROUGH WHICH WILL
CROSS THE APPALACHIANS LATE EVENING AND OVERNIGHT. CONVECTION SHOULD
BECOME WIDESPREAD ACROSS THE SRN/CNTRL APPALACHIANS EARLY IN THE
PERIOD...WHILE ADDITIONAL TSTM DEVELOPMENT IS POSSIBLE INTO THE VA
TIDEWATER AND NRN NC...WHERE RELATIVELY HIGHER CONFIDENCE EXISTS IN
MORE SUBSTANTIAL DIURNAL DESTABILIZATION OCCURRING. MODERATELY
STRONG DEEP-LAYER SHEAR COUPLED WITH THE MOIST/UNSTABLE AIR MASS
SHOULD SUPPORT AT LEAST ISOLATED STRONG TO SVR CONVECTION WITH THE
POTENTIAL FOR DMGG WIND GUSTS AND HAIL. LESS CONFIDENCE EXISTS IN
THE DEGREE OF DESTABILIZATION THAT WILL OCCUR FARTHER W/N ACROSS VA
AND NRN NC...BUT THIS AREA WILL BE MONITORED FOR POSSIBLE SLIGHT
RISK EXPANSION IN FUTURE OUTLOOKS.

..ROGERS.. 07/27/2016

$$



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