Mesoscale Discussion 1946

Issued

Sep 12, 2012, 2:59 PM CDT (19:59 UTC)

Expired

Sep 12, 2012, 5:00 PM CDT

In force

2 hr

Issued by

the Storm Prediction Center

Chance of a watch

5%

The Vance AFB radar (KVNX), 144 km from the middle of the area, began a volume at 19:58 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

567 
ACUS11 KWNS 121959
SWOMCD
SPC MCD 121959 
KSZ000-OKZ000-TXZ000-122200-

MESOSCALE DISCUSSION 1946
NWS STORM PREDICTION CENTER NORMAN OK
0259 PM CDT WED SEP 12 2012

AREAS AFFECTED...S-CNTRL KS...NWRN OK...ERN PARTS OF THE TX
PANHANDLE/TX SOUTH PLAINS

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 121959Z - 122200Z

PROBABILITY OF WATCH ISSUANCE...5 PERCENT

SUMMARY...THE POTENTIAL FOR VERY ISOLATED SVR MICROBURSTS WILL EXIST
THROUGH LATE AFTERNOON...AND THE ISSUANCE OF A WW IS NOT NEEDED.

DISCUSSION...ASCENT ASSOCIATED WITH A SHARP FRONT LYING FROM S-CNTRL
KS INTO THE TX PANHANDLE IS BEING AUGMENTED BY DIFFERENTIAL HEATING
OVER THE ERN FLANK OF AN ACCAS FIELD IN ERN PARTS OF THE TX
PANHANDLE/SOUTH PLAINS. CUMULUS DEVELOPMENT WITHIN THIS ZONE OF
ASCENT HAS BEEN RELATIVELY LACKING THUS FAR -- OWING TO INHIBITION
ASSOCIATED WITH THE EML AND RETURN OF AN ONLY PARTIALLY MODIFIED
MOIST AIR MASS. HOWEVER...ADDITIONAL INSOLATION MAY AID IN
CONVECTIVE DEVELOPMENT WITHIN THE NEXT COUPLE OF HOURS AMIDST
200-400 J/KG OF MLCAPE PER MODIFIED 12Z RAOBS. AN ISOLATED STORM OR
TWO COULD ALSO EVOLVE FROM ONGOING SHALLOW CUMULUS DEVELOPMENT NOTED
EAST OF THE FRONT AND ACCOMPANYING MESO-LOW FROM NWRN OK INTO
S-CNTRL KS...WHERE DEEP BOUNDARY-LAYER CIRCULATIONS EXIST. DCAPE OF
1000-1400 J/KG AND SFC TEMPERATURE-DEWPOINT SPREADS OVER 35F WOULD
CONDITIONALLY SUPPORT INTENSE MICROBURSTS YIELDING A VERY ISOLATED
SVR WIND THREAT. THE DURATION OF ANY SVR THREAT SHOULD BE CURTAILED
BY THE UNDERCUTTING FRONT...WHILE LACKING INSTABILITY/DEEP SHEAR
SHOULD LIMIT UPDRAFT STRENGTH.

..COHEN/PETERS.. 09/12/2012

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...ICT...OUN...DDC...LUB...AMA...

LAT...LON   35719995 34860004 33679991 33660020 34070041 34790065
            36010088 36550033 36970001 37919947 38159841 37919784
            37509782 36989817 36599855 36229903 35719995

Mesoscale Discussions in Kansas, 2012Mesoscale Discussions in Texas, 2012Mesoscale Discussions in Oklahoma, 2012Every mesoscale discussion in 2012

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.