-MKC AC 010552

CONVECTIVE OUTLOOK...REF AFOS NMCGPH94O.

VALID 011200Z - 021200Z

REF WW NUMBER 544...VALID TIL 0700Z

THERE IS A HIGH RISK OF SVR TSTMS THIS AFTN AND TNGT ACRS PARTS OF NERN NEB...SERN SD...MOST OF IA...SRN SXNS OF MN...AND SWRN WI. THE HIGH RISK AREA IS TO THE RIGHT OF A LINE FROM 20 SSE DSM OMA 25 E OLU 15 W OFK 30 SSW MHE 20 E HON 15 NNE ATY 30 SE AXN 20 N EAU 25 SW CWA 20 W JVL 25 WNW MLI 20 SSE DSM.

SURROUNDING THE HIGH RISK AREA...THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 10 S FNB HSI 35 ESE MHN 55 W VTN 25 ENE RAP 30 W Y22 30 W BIS 25 WNW JMS FAR DLH 20 W MQT 15 E ESC 15 S TVC 25 ESE AZO 35 NW LAF 30 ESE IRK 10 S FNB.

GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM PSX HOU 40 N BPT 35 NE SHV 10 NE FYV 25 ESE CNU EMP 20 NE RSL 30 SE IML 25 SE BFF 25 S 4DG 25 NW BPI 15 E BYI 45 NW OWY 30 NW BNO 35 E BLI...CONT... 15 E MSS 25 SSW MSV WAL.

...SEVERE THUNDERSTORM FORECAST DISCUSSION...
PARAMETERS APPEAR TO BE COMING TOGETHER FOR A SIGNIFICANT SVR WX EPISODE THIS AFTN AND THRU THE NGT. RATHER STG UPR LVL LOW PRESSURE CENTER CURRENTLY LOCATED OVR THE NRN INTRMTRGN WL CONT TO MOV EWD ACRS THE NRN RCKYS AND INTO THE PLNS DURG THE DY1 PD. ASSOCD SFC LOW/CDFNT WL MOV RAPIDLY EWD FM THE NRN PLNS TO THE WRN GRTLKS RGN BY 02/12Z.

...NRN PLNS INTO THE WRN GRTLKS...
BY THE BEGINNING OF THIS PD...AN AREA OF LOW PRESSURE WL DVLP IN XTRM NERN WY/WRN SD. AS THE STG UPR LVL FORCING CONTS TO MOV RAPIDLY EWD...THE SFC LOW WL CONT TO DEEPEN AS IT MOVS INTO THE NRN PLNS/UPR MS VLY. AS THE LOW DEEPENS...INCRG SLY LOW LVL FLOW WL REINFORCE THE PLENTIFUL MSTR ALREADY IN PLACE THRUT MUCH OF THE PLNS RGN/MS VLY. WITH STG AFTN HEATING EXPCD THIS AFTN...VRY STG INSTBY SHOULD BCM ESTABLISHED...PARTICULARLY ACRS THE HIGH RISK AREA WITH SFC BASED CAPE VALUES TO 4500 J/KG BY LATE AFTN. A SEASONALLY STG WLY MID LVL JET WL MOV OUT OF THE PLNS AND ACRS THE OTLK AREA...AND THE RESULT WL BE TREMENDOUS SPEED AND DIRECTIONAL SHEAR.

AN AREA OF TSTMS CURRENTLY IN SD WL LIKELY CONT TO MOV ACRS THE STATE AND INTO THE OTLK AREA ERY THIS MRNG. GIVEN THE STRENGTH OF THE LOW LVL WNDS...AMS RECOVERY SHOULD TAKE PLACE DURG THE LATE MRNG AND INTO THE ERY AFTN. STG CNVGNC ALG/AHD OF THE FNT SHOULD AID TSTM DVLPMT DURG THE LATE MRNG/ERY AFTN HRS. AS THE ACTVTY MOVS INTO THE STGR INSTBY AND SHEAR...EXPC TSTMS SHOULD RAPIDLY BCM SVR. PRIND ACTVTY SHOULD BEGIN AS ISOLD/WDLY SCT SUPERCELLS OVR SD/NEB. CELLS SHOULD BCM MORE NMRS AS THEY APCH THE HIGH RISK AREA AS FORCING CONTS TO WEAKEN THE CAP...BEFORE EVOLVING INTO A SQLN. VRY LRG HAIL...DMGG WNDS...AND TORNADOES ARE LIKELY WITH THIS ACTVTY. WITH THE INCRG LOW AND MID LVL WNDS...THE LN SHOULD ACLT EWD ACRS THE NRN/MID MS VLY INTO THE GRTLKS RGN. AT THIS POINT...DMGG WNDS SHOULD BCM THE PREDOMINANT THREAT DURG THE OVERNIGHT HRS.

A PUBLIC SVR WX OTLK /AFOS HEADER PWOMKC/ WL BE ISSUED BY 10Z.

...GENERAL THUNDERSTORM FORECAST DISCUSSION...

...NWRN U.S...
NXT IN A SERIES OF SHRTWV TROFS WL MOV INLAND AND ACRS PARTS OF THE NWRN U.S. THIS FCST PD. MID LVL TEMPS /H5 VALUES TO ARND -20 DEG C/WL BEGIN TO SPREAD INLAND DURG THE AFTN HRS. AS THIS OCRS AND STG SFC HEATING COMMENCES...LAPSE RATES WL STEEPEN ACRS MUCH OF THE AREA. WATER VAPOR IMAGERY SHOWS PLENTIFUL MID LVL MSTR OVR THIS RGN. GIVEN THE STEEP LAPSE RATES AND AVBL MSTR...EXPC SCT TSTMS WL DVLP DURG THE AFTN HRS...PARTICULARLY IN THE HIER TERRAIN.

...SERN U.S...
SEASONALLY MOIST AND UNSTBL AMS IS LIKELY TO PERSIST ACRS MUCH OF THE SERN U.S. THRUT THE DY1 PD. PERSISTENT WK SFC TROFS WL CONT OVR THE CAROLINAS INTO THE SRN APLCNS. EXPC SFC HEATING...THESE WK SFC TROFS...AND SEA BREEZE CIRCULATIONS SHOULD BE SUF FOR WDLY SCT/SCT
AFTN TSTMS. THE LACK OF STG UPR LVL SUPPORT SHOULD PRECLUDE ORGANIZED SVR ACTVTY.

..REHBEIN.. 07/01/97