Mesoscale Discussion 1985

Issued

Sep 25, 2012, 3:22 PM CDT (20:22 UTC)

Expired

Sep 25, 2012, 4:15 PM CDT

In force

53 min

Issued by

the Storm Prediction Center

Chance of a watch

40%

The Altus AFB radar (KFDR), 143 km from the middle of the area, began a volume at 20:21 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.

171 
ACUS11 KWNS 252022
SWOMCD
SPC MCD 252022 
KSZ000-OKZ000-TXZ000-252115-

MESOSCALE DISCUSSION 1985
NWS STORM PREDICTION CENTER NORMAN OK
0322 PM CDT TUE SEP 25 2012

AREAS AFFECTED...ERN TX PANHANDLE...WRN OK...S-CNTRL KS

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 252022Z - 252115Z

PROBABILITY OF WATCH ISSUANCE...40 PERCENT

SUMMARY...INCREASING TSTM DEVELOPMENT IS EXPECTED DURING THE NEXT
HOUR OR TWO ACROSS THE ERN TX PANHANDLE WITH EWD MOTION INTO WRN OK.
SEVERE HAIL/DAMAGING WINDS ARE POSSIBLE IN THE STRONGER STORMS.
CONVECTIVE TRENDS WILL BE MONITORED FOR A POSSIBLE WW...ESPECIALLY
OVER WRN OK AND S-CNTRL KS.

DISCUSSION...SURFACE ANALYSIS DEPICTS A SFC LOW CENTERED ACROSS FAR
SWRN KS WITH A DRYLINE EXTENDING SWD ACROSS THE TX PANHANDLE AND IN
THE TX SOUTH PLAINS. DEVELOPMENT OF THIS SURFACE LOW AS WELL AS THE
SHARPENING AND EWD PROGRESSION OF THE DRYLINE HAVE BEEN AIDED BY A
SPEED MAX...EVIDENT IN WATER VAPOR IMAGERY...MOVING ACROSS NRN NM.
VISIBLE SATELLITE IMAGERY SHOWS A DEEPENING CU FIELD ALONG THE
DRYLINE AND CONVECTIVE INITIATION HAS OCCURRED JUST E OF PPA. STEEP
MID-LEVEL LAPSE RATES /GREATER THAN 8 DEG C PER KM/ COMBINED WITH
AMPLE DAYTIME HEATING AND TEMPERATURES IN THE 90S WILL RESULT IN
MODERATE INSTABILITY...WITH MLCAPE AROUND 15OO J/KG ANTICIPATED
ACROSS MOST OF THE ERN TX PANHANDLE. THE BEST LOW-LEVEL
MOISTURE...AND THEREFORE THE BEST INSTABILITY...EXISTS FARTHER E
OVER WRN/CNTRL OK. 

EARLY ACTIVITY WILL LIKELY BE SHORT-LIVED AND UNORGANIZED...OWING
PRIMARILY TO THE WEAK BULK SHEAR. HOWEVER...LARGE
TEMPERATURES-DEWPOINT SPREADS WILL PROMOTE STRONG COLD POOL
GENERATION WITH RESULTANT UPDRAFT DEVELOPMENT CONTINUING ALONG THE
COLD POOL AS IT MOVES E. INCREASED INSTABILITY AND ENHANCED
MID-LEVEL FLOW ASSOCIATED WITH THE APPROACHING SPEED MAX AND LOW
LEVEL JET DEVELOPMENT WILL PROMOTE GRADUAL STRENGTHENING AND
ORGANIZATION AS THIS ACTIVITY MOVES INTO WRN OK LATER THIS AFTERNOON
AND EVENING. 

PRIMARY THREAT WITH THE INITIAL ACTIVITY IS EXPECTED TO BE
STRONG...A FEW POSSIBLY SEVERE...WIND GUSTS. HAIL CANNOT BE RULED
OUT BUT THE WEAK SHEAR AND MODEST INSTABILITY SHOULD LIMIT IT/S SIZE
AND OCCURRENCE. INCREASING SHEAR AND INSTABILITY WILL RESULT IN AN
INCREASING LIKELIHOOD FOR BOTH SEVERE HAIL/WIND AS THE ACTIVITY
MOVES INTO WRN OK. CONVECTIVE TRENDS WILL BE MONITORED FOR A
POSSIBLE WW.

..MOSIER/GUYER/MEAD.. 09/25/2012

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

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

LAT...LON   34060041 34270107 34890099 35480086 36480044 37010010
            37319967 37419908 37449824 37339790 36849772 36109820
            35729838 35309852 34989862 34699874 34459889 34249916
            34099959 34060041

Mesoscale Discussions in Oklahoma, 2012Mesoscale Discussions in Texas, 2012Mesoscale Discussions in Kansas, 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.