Severe Storm Outlook Narrative (AC)
Issued by NWS

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ACUS02 KWNS 220554
SWODY2
SPC AC 220552

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1252 AM CDT MON SEP 22 2014

VALID 231200Z - 241200Z

...NO SVR TSTM AREAS FORECAST...

...SUMMARY...
ISOLATED TO WIDELY SCATTERED THUNDERSTORMS WILL BE POSSIBLE ON
TUESDAY...PARTICULARLY ACROSS PARTS OF THE CENTRAL PLAINS...SOUTHERN
ROCKIES...AND COASTAL SOUTHEAST UNITED STATES. A FEW OF THE STORMS
ACROSS THE CENTRAL HIGH PLAINS COULD BE STRONG TO SEVERE.

...SYNOPSIS...
A SPLIT UPPER-FLOW PATTERN WILL UNDERGO A DEGREE OF AMPLIFICATION
TUESDAY AS RELATIVELY WEAK WESTERLIES PERSIST OVER MOST OF THE
CONUS. A REMNANT UPPER LOW/SHORTWAVE TROUGH OVER THE NORTH-CENTRAL
HIGH PLAINS EARLY TUESDAY WILL CONTINUE TO MOVE EAST-NORTHEASTWARD
AND WEAKEN OVER THE DAKOTAS/UPPER MIDWEST. ASSOCIATED WARM ADVECTION
WILL CONTRIBUTE TO THUNDERSTORMS ACROSS THE CENTRAL PLAINS/UPPER
MIDWEST BEGINNING EARLY IN THE PERIOD...WHILE OTHER POTENTIALLY
STRONG/SEVERE THUNDERSTORMS DEVELOP LATER IN THE DAY IN
VICINITY OF A CENTRAL PLAINS LEE TROUGH. THUNDERSTORMS WILL ALSO BE
POSSIBLE ALONG/SOUTH OF A REMNANT FRONTAL ZONE ACROSS FL AND SOUTH
TX.

...CENTRAL PLAINS...
AFOREMENTIONED UPPER LOW/SHORTWAVE TROUGH WILL GENERALLY SPREAD
EAST-NORTHEASTWARD AWAY FROM THE REGION DURING THE DAY...WITH
RELATIVELY WEAK CYCLONIC WESTERLIES WILL BE COINCIDENT WITH AN
EASTWARD-SHIFTING SURFACE TROUGH. WHILE OVERALL FORCING WILL BE
RELATIVELY WEAK...SUFFICIENT HEATING/CONVERGENCE NEAR THE LEE TROUGH
COULD CONTRIBUTE TO ISOLATED SURFACE-BASED THUNDERSTORM DEVELOPMENT
TUESDAY AFTERNOON/EARLY EVENING ACROSS WESTERN PORTIONS OF NEB/KS.
ON THE WESTERN FRINGE OF EARLY DAY CLOUD COVER/SCATTERED
PRECIPITATION...CURRENT THINKING IS THAT MLCAPE COULD REACH/EXCEED
1000 J/KG BY PEAK HEATING IN VICINITY OF THE TROUGH. ALTHOUGH WINDS
WILL STRONGLY VEER WITH HEIGHT...MODEST LOW/MID TROPOSPHERIC WIND
SPEEDS WILL TEND TO LIMIT EFFECTIVE SHEAR TO AROUND 30 KT. WITH SOME
SUSTAINED MULTICELLS/BRIEF SUPERCELLS POSSIBLE...LOW SEVERE
PROBABILITIES APPEAR WARRANTED...MAINLY RELATED TO AN
EPISODIC/MARGINAL SEVERE HAIL POTENTIAL BETWEEN TUESDAY
MID-AFTERNOON AND MID-EVENING.

..GUYER.. 09/22/2014



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