Severe Storm Outlook Narrative (AC)
Issued by NWS

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000
ACUS01 KWNS 172007
SWODY1
SPC AC 172005

DAY 1 CONVECTIVE OUTLOOK RESENT 1
NWS STORM PREDICTION CENTER NORMAN OK
0305 PM CDT WED SEP 17 2014

VALID 172000Z - 181200Z

...NO SVR TSTM AREAS FORECAST...

...SUMMARY...
ISOLATED SEVERE STORMS WILL BE POSSIBLE OVER PARTS OF THE CENTRAL
GREAT PLAINS AND OZARK PLATEAU TODAY AND TONIGHT. A FEW STRONG
STORMS ARE LIKELY OVER PORTIONS OF SOUTH CAROLINA...SOUTHEASTERN
GEORGIA...THE MOJAVE DESERT...AND PERHAPS OVER FAR SOUTHERN ARIZONA.

...SERN GA...SC...
STRONG HEATING HAS LED TO A VERY UNSTABLE AIR MASS ALTHOUGH A LOT OF
MIDLEVEL DRY AIR EXISTS ACROSS THE REGION WITH RELATIVELY POOR
MIDLEVEL LAPSE RATES. HOWEVER...SURFACE CONVERGENCE NEAR A WEAK
FRONT ACROSS CNTRL SC AND AFOREMENTIONED HEATING ARE HELPING TO
FOCUS DEVELOPMENT AND MAXIMIZE UPDRAFT STRENGTH. FURTHER...NWLY FLOW
ALOFT APPEARS TO BE JUST STRONG ENOUGH TO SUPPORT A MORE CELLULAR
STORM MODE...WITH AROUND 25 KT 500 MB FLOW AND AN UPPER-LEVEL JET
MAX NOSING INTO THE REGION LATER TODAY. LOCAL RADAR SHOWS MIDLEVEL
ROTATION IN SOME OF THESE SMALL CELLS. THEREFORE...ISOLATED
MARGINALLY SEVERE HAIL WILL BE POSSIBLE...WITH LOCALIZED WET
MICROBURSTS AS WELL.

...SRN MO...NRN AR...FAR ERN OK...
ISOLATED CELLS CONTINUE TO PROPAGATE SWD WITH TIME ACROSS SRN MO AND
NRN AR IN ASSOCIATION WITH AN ONGOING DISTURBANCE WHICH CONTINUES TO
PUSH SEWD. A PLUME OF HIGHER THETA-E AIR CURRENTLY EXTENDS FROM ERN
OK INTO NWRN AR...AND THIS SHOULD SUPPORT FURTHER DEVELOPMENT AS THE
OUTFLOW BOUNDARY CONTINUES TO DRIFT SWWD. HOWEVER...THIS BOUNDARY
DOES APPEAR TO BE UNDERCUTTING THE ACTIVITY...AND IS ONLY MOVING AT
AROUND 35 KT SUGGESTING ONLY MARGINAL WINDS. HAIL CORES WILL
CONTINUE TO BE THE MAIN THREAT.

..JEWELL.. 09/17/2014

.PREV DISCUSSION... /ISSUED 1132 AM CDT WED SEP 17 2014/

...SYNOPSIS...
LITTLE CHANGE IS EXPECTED IN THE LARGE-SCALE PATTERN...WITH A BROAD
TROUGH OVER THE ERN CONUS...A RIDGE OVER THE ROCKIES...AND ANOTHER
TROUGH NEAR THE PAC COAST.  AN ASSOCIATED SLOW-MOVING FRONTAL ZONE
WILL PERSIST FROM THE SE ATLANTIC COAST AND GULF COAST STATES NWWD
INTO THE CENTRAL PLAINS AND NRN HIGH PLAINS THROUGH THE
PERIOD...WHILE THE REMNANT CIRCULATION WITH TC ODILE DRIFTS NEWD
INTO SRN AZ.

...SW MO/SE KS/ERN OK/WRN AR THIS AFTERNOON...
CLUSTERS OF SLIGHTLY ELEVATED THUNDERSTORMS ARE ONGOING FROM SW MO
INTO N CENTRAL AR IN A ZONE OF LOW-LEVEL WAA RELATED TO A SUBTLE
MID-UPPER SPEED MAX TRANSLATING SEWD OVER MO.  DAYTIME
HEATING/DESTABILIZATION IMMEDIATELY SW OF THE ONGOING STORMS SHOULD
LEAD TO A TENDENCY FOR THE CONVECTION TO DEVELOP SWWD DURING THE
AFTERNOON AS THE OUTFLOW-REINFORCED FRONT INTERACTS WITH THE WARM
SECTOR...AS CONVECTIVE INHIBITION WEAKENS AND MLCAPE INCREASES TO
2000-2500 J/KG.  EFFECTIVE BULK SHEAR AROUND 30 KT WILL BE
SUFFICIENT FOR SOME STORM CLUSTER ORGANIZATION...AND PERHAPS
MARGINAL SUPERCELL STRUCTURES.  ISOLATED LARGE HAIL AND DAMAGING
WINDS WILL BE POSSIBLE WITH THE STRONGEST STORMS AS THE CLUSTER
DEVELOPS SWD/SWWD THROUGH THE AFTERNOON.



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