Severe Thunderstorm Warning 311, NWS Dodge City, KS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERCIVE DODGE CITY KS
322 PM CDT WED AUG 12 1998

...FCST CHALLENGE IS HOW CONVECTION DEVELOPS THIS AFTERNOON AND
INTERACTS WITH COMPLEX UPPER TROUGH...

MODELS HAVING PROBLEMS WITH VORT MAX OVER SOUTH DAKOTA AND
CONVECTIVELY INDUCED VORT MAX NEAR AMA PER SATELLITE.  THESE SYSTEMS
WILL MERGE OVER OKLAHOMA NEXT 24-36 HOURS.  CONVECTION NEAR GAG
HAS BECOME WIDESPREAD WHICH SHOULD LIMIT SOMEWHAT POTENTIAL FOR
CONVECTION AS IT DEVELOPS NORTH OF GLD BY LATE AFTERNOON BY
ROBBING MOISTURE AS VORT MOVES SOUTH ALONG OLD FRONTAL BOUNDARY.
ALL MODELS HANDLE PRECIPITATION POORLY WITH NGM/ETA SHOWING WAY TOO
MUCH PRECIP OVER CWA TODAY AND NOT ENOUGH TO THE SOUTH OVER
OKLAHOMA FROM LEFTOVER CONVECTIVE SYSTEM LAST NIGHT.  AVN LEANS
OTHER WAY WITH MOST PRECIP TONIGHT OVER NW KS AND MOVING SOUTH INTO
OKLAHOMA.  SHORT FUSE COMPOSITE...SATELLITE AND UEX 88D SUPPORTS SE
SOLUTION TO A CERTAIN EXTENT AT 20Z.  AGAIN..THE ONLY FLY
IS WHAT HAPPENS NEXT FEW HOURS WITH CONVECTION IN OKLAHOMA AND
CENTRAL KANSAS IF DECREASES THEN INCREASES CHANCE OF TSRA WITH MAIN
VORT LOBE AS IT MOVES SOUTH INTO KS FROM NE.

POPS WILL DEFINITELY GO HIGHER THAN FWC AND CLOSE TO AVN FAN POPS.
BEST CHANCE SHOULD BE EASTERN 2/3 CWA.  LOWS WILL GO NEAR FWC
GUIDANCE SINCE BY LATE EXPECT MOST CONVECTION TO BE WELL SE OF CWA.
XPCT LOW CLOUDS AND SOME POSSIBLE FOG LATE TONIGHT WITH NE UPSLOPE
WINDS AND POST CONVECTIVE SUBSIDENCE TO AID LOW CLOUDS.

PRD 2 ON THURSDAY WILL GO WITH SOME CLOUDS AND MAYBE LOW POPS IN AM
BECOMING MOSTLY SUNNY BY PM WITH TIMING DEPENDING ON LOCATION IN CWA
AS CLEARING WILL BE FROM NW TO SE. TEMPS ON FWC AGAIN TOO HIGH AND
WITH MID AND UPPER LEVEL TEMPS STAYING THE SAME SEE LOW TO MID 80S
ALL CWA OR 1 TO 2 CATEGORIES BELOW FWC OR ABOUT ONE CATEGORY ABOVE
FAN.  IF CLOUDS HOLD IN LONGER SOME AREAS MAY NOT EVEN SEE 80 BUT
DEPENDS ON HOW CLOUDS PRECIP EVOLVES.

PRD 3 CLEARING TO CONTINUE AS NORTH WINDS SFC AND ALOFT WILL DRY OUT
AND FWC SHOULD HANDLE TEMPS WELL.  POSSIBLE PATCHY FOG BUT WILL
LEAVE FOR LATER PERIODS TO CONSIDER AS TOO MUCH UNCERTAINTY ATTM.

PRD 4 SLOW WARMING TREND AND FAN/FWC ARE BOTH CLOSE AND WILL GO WITH
THOSE SOLUTIONS AS PROGGED HEIGHTS AND THICKNESS SUPPORTS TEMPS WITH
FULL SUN WHICH SHOULD BE THE CASE.

.EXTENDED FORECAST...EXTENDED RANGE MODELS ARE IN REASONABLE
AGREEMENT IN DROPPING THE STRONG VORTICITY MAXIMUM EVIDENT ON
SATELLITE IMAGERY AND MORNING ANALYSES OVER NORTHEASTERN
NEBRASKA/SOUTHEASTERN SOUTH DAKOTA SOUTHWARD OVER THE CENTRAL PLAINS
IN THE SHORT TERM...THEN CLOSING THE SYSTEM OFF OVER OKLAHOMA BY
FRIDAY.  THE CLOSED LOW THEN WALLOWS OVER EASTERN TEXAS FOR DAYS
WHILE RIDGING ALOFT BUILDS OVER THE CENTRAL PLAINS.  SOME SUBSIDENCE
UNDER THE UPPER LEVEL RIDGE SHOULD RESULT IN A DIMINUTION OF
CONVECTION OVER THE WEEKEND...BUT CONFIDENCE IS NOT GREAT THAT THERE
WILL BE SUFFICIENT SUBSIDENCE TO STABILIZE THE ATMOSPHERE ENOUGH TO
PRECLUDE DEVELOPMENT OF A FEW THUNDERSTORMS.  FURTHERMORE...THE
STRONG SHORT WAVE MOVING ACROSS NORTHERN BRITISH COLUMBIA THIS
AFTERNOON LIKELY WILL DROP SOUTHEASTWARD INTO THE LONG WAVE TROUGH
OVER THE MIDWEST SATURDAY...AND A WEAK COLD FRONT MAY ADVANCE AS FAR
SOUTH AS KANSAS SATURDAY AFTERNOON AND SATURDAY NIGHT.  WEAK
CONVERGENCE ALONG THIS BOUNDARY SHOULD BE SUFFICIENT TO SUPPORT A
FEW THUNDERSTORMS FROM SATURDAY AFTERNOON THROUGH SUNDAY.  AT THIS
POINT...MONDAY STILL LOOKS FAIRLY QUIET.  TEMPERATURES WILL BE SLOW
TO WARM AND LIKELY WILL HOLD AROUND SEASONAL NORMALS EVEN UNDER THE
UPPER LEVEL RIDGE SINCE MUCH OF THE INSOLATION WILL BE CONSUMED BY
THE UNSEASONABLY ACTIVE VEGETATION.

.DDC...NONE.

PRELIMINARY GUIDANCE FOR COORDINATION ONLY. OFFICIAL FORECASTS ARE
CONTAINED WITHIN THE DODGE CITY ZONE FORECAST.

DDC 063/083 061/088 065 42-
GCK 061/084 059/087 064 31-
EHA 060/085 057/089 063 2--
LBL 061/085 060/089 064 2--
HYS 060/082 058/087 064 42-
P28 065/083 062/089 067 741

NICHOLS/RUTHI