Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS02 KWNS 230559
SWODY2
SPC AC 230557

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1257 AM CDT WED JUL 23 2014

VALID 241200Z - 251200Z

...THERE IS A SLGT RISK OF SVR TSTMS FOR PARTS OF THE WRN DAKOTAS
AND ERN MT...

...SUMMARY...
SEVERE STORMS ARE POSSIBLE OVER PARTS OF THE NORTHERN GREAT PLAINS
ON THURSDAY AFTERNOON AND EVENING. STRONG TO LOCALLY SEVERE STORMS
ARE ALSO POSSIBLE OVER PARTS OF THE SOUTHEAST.

...SYNOPSIS...
A VIGOROUS SHORTWAVE TROUGH OVER THE PACIFIC NW WILL IMPINGE ON THE
NRN PLAINS/CANADIAN PRAIRIES RIDGE AS IT REACHES THE LEE OF THE
CANADIAN SRN ROCKIES BY EARLY FRI. ALTHOUGH GUIDANCE CONTINUES TO
DIFFER ON SPEED...AN ATTENDANT SURFACE COLD FRONT WILL PUSH E/SE
ACROSS PARTS OF THE NRN PLAINS. FARTHER E...A BROAD MID-LEVEL TROUGH
WILL PERSIST ACROSS SE CANADA INTO THE ERN CONUS. A SURFACE COLD
FRONT SHOULD WEAKEN AS IT PROGRESSES INTO THE SOUTHEAST.

...NRN PLAINS...
A RELATIVELY NARROW PLUME OF LOWER TO MIDDLE 60S SURFACE DEW POINTS
IS ANTICIPATED TO BE CENTERED FROM CNTRL KS INTO WRN/CNTRL ND THU
AFTERNOON. WITH VERY STEEP TROPOSPHERIC LAPSE RATES...NEAR 9 DEG
C/KM FROM 700-500 MB...POTENTIAL BUOYANCY SHOULD BECOME MODERATE TO
STRONG WITHIN THIS CORRIDOR. GUIDANCE DIFFERS ON SPATIOTEMPORAL
DETAILS WITH WHERE TSTM INITIATION WILL OCCUR ALONG THE FRONT /ECMWF
REMAINING FARTHER W IN ERN MT/. FORCING FOR ASCENT THROUGH MID-LEVEL
HEIGHT FALLS AND CONVERGENCE ALONG THE FRONT SHOULD BE SUFFICIENT TO
OVERCOME INHIBITION AND YIELD AT LEAST ISOLATED STORMS BY LATE
AFTERNOON. DEEP-LAYER SHEAR WILL BE FAVORABLE FOR A COUPLE OF
SUPERCELLS WHICH MAY CONGEAL INTO A CLUSTER WITH SEVERE WIND/HAIL.
THE ERN EXTENT OF THE RISK THU EVENING SHOULD BE LIMITED BY
SUBSTANTIAL MLCIN.

...PARTS OF THE SOUTHEAST...
A BELT OF ENHANCED MID/UPPER-LEVEL W/SWLYS IS EXPECTED TO OVERLAP
THE REMAINING PRE-FRONTAL WARM SECTOR THROUGH THU EVENING. WITH
AROUND 30-35 KT FLOW AT 500 MB...SCATTERED STORMS ALONG THE FRONT
AND SEA BREEZE MAY BECOME SEMI-ORGANIZED WITH A THREAT FOR ISOLATED
DAMAGING WINDS. HOWEVER...MARGINAL MID-LEVEL LAPSE RATES AND WEAK
LOW-LEVEL WINDS SHOULD DISCOURAGE AN ORGANIZED SEVERE WIND RISK.

..GRAMS.. 07/23/2014




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