Severe Thunderstorm Warning 171, NWS Wichita, KS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WICHITA KS
225 AM CDT THU JUL 27 2000

FCST CHALLENGE REMAINS AREAL COVERAGE OF PRECIP THIS AM...THEN
LOCATION AND MOVEMENT OF NEXT COMPLEX TONIGHT...INTO FRIDAY...WITH
CORRESPONDING PRECIP CHANCES AND TEMPS THE FOCUS.

AFTER LOOKING AT SAT PICS AND UPPER AIR/SFC MAPS WILL LEAN TOWARD
USING AN AVN/ETA BLEND FOR GUIDANCE THIS TIME AROUND.

FIRST COMPLEX DIVING SOUTH AND DECAYING AS IT OUTRUNS THE THETAE
RIDGE WHILE THE OUTFLOW HAS SURGED SOUTH AND WEST...AND SHOULD MOVE
TO NEAR ICT TO SLN IN THE NEXT FEW HOURS. MEANWHILE...STRONG
TEMPERATURE ADVECTION IN THE 850-750 MB LAYER IS SUSTAINING THE
CURRENT ACTIVITY ACROSS CENTRAL KS. EXPECT THE COMBINATION OF STRONG
WAA THROUGH 12Z ALONG WITH SOME ENHANCEMENT FROM OUTFLOW TO SUSTAIN
SCATTERED STORMS THROUGH MID MORNING BEFORE THE TEMPERATURE
ADVECTION DECREASES AND ATMOSPHERE BEGINS TO RECOVER. LATEST SURFACE
MAP DEPICTS DIFFUSE BOUNDARY ACROSS SOUTHERN NEBRASKA WITH HIGHEST
DEWPOINTS/SFC THETAE RIDGE EXTENDING FROM NEAR HASTINGS INTO
NORTHERN OK. WILL WORD SCATTERED MORNING STORMS CENTRAL AND SOUTH
CENTRAL WITH BECOMING PTSUNNY WORDING BY AFTERNOON WITH A 20 POP
CENTRAL NEARER TO THE FRONT. FOR SE KS WILL CARRY GENERIC 30
POPS ALL DAY WITH SLIGHTLY COOLER MID LEVEL TEMPS AND SOME
INDICATION OF WEAK UPPER DIV LINGERING. FOR MAX TEMPS WILL GO AROUND
90 CENTRAL AND SOUTH CENTRAL WITH UPPER 80S SE.

MAIN SHOW TO OCCUR TONIGHT AS STRETCHED AXIS OF VORTICITY RIDES
THROUGH THE RIDGE ACROSS THE REGION. BEST MOISTURE POOLING FROM
SFC-850 FCST TO OCCUR ALONG AND NORTHEAST OF THE BOUNDARY ACROSS NE
KS WHERE STRONGEST TEMPERATURE ADVECTION AND THETAE ADVECTION ARE
ALSO FORECAST TO OCCUR. UPPER DIV ALSO FORECAST TO INCREASE WHICH
WILL SUPPORT STORMS THAT FEED OFF OF LOWER FORCING FROM 35-40KT LLJ.
CORFIDI VECTORS INDICATE A SE MOVEMENT OF MAIN CONVECTIVE ELEMENT
ACROSS TOPEKA/S CWA WITH SOME BACKBUILDING INTO A INCREASINGLY VEERED
LLJ LIKELY AFTER MIDNIGHT. AS A RESULT...WILL CONTINUE TO CARRY 50
POPS FOR CENTRAL KS DESPITE BEING SOUTH OF BOUNDARY AND SOUTHWEST OF
TEMP/MOISTURE ADVECTION. WILL CARRY HIGHEST POPS SE...

BY FRIDAY...ALL WILL DEPEND ON AREAL EXTENT AND INTENSITY OF
OVERNIGHT CONVECTION WHICH WILL CONTROL THE SFC BOUNDARY POSITION AND
HENCE WIND DIRECTIONS. AT THIS TIME WILL HEDGE SLIGHTLY COOLER THEN
GUIDANCE WITH 80 TO 85 RANGE FEELING THAT ANY EFFECTIVE BOUNDARY WILL
PUSH SOUTH...WITH EARLY MORNING LINGERING PRECIP/LOW CLOUDS TO LIMIT
MORNING TEMPS...WITH NE WINDS AND WEAK CAA TO LIMIT AFTERNOON
HEATING FOR CENTRAL. SFC BOUNDARY POSITION MAY BE SOMEWHERE NEAR OK
BORDER ACROSS SE KS.  AT THE SAME TIME...AVN SHOWS WAVE NOW ACROSS
THE NORTHERN ROCKIES WILL DIVE SOUTH AND MAY ENHANCE MESOSCALE LIFT
NEAR FRONT BY FRIDAY AFTERNOON.  THUS WILL CARRY GENERIC 40 POPS
SOUTHERN TIER OF CWA.

OVERALL PRECIP THREAT SHOULD BEGIN TO WANE FRIDAY NIGHT INTO
SATURDAY AS UPPER TROUGH AXIS SHARPENS AND ALLOWS COOLER AND DRIER
AIR TO CONTINUE TO INVADE THE STATE. ALTHOUGH SOME EARLY PRECIP IS
POSSIBLE FAR SOUTH...FEEL THAT THE WEEKEND COULD TURN OUT GREAT WITH
AREA NORTH OF SHARP UPPER TROUGH AXIS WITH MAIN WESTERLY FLOW WELL
NORTH AND SFC BOUNDARY/DEEP MOISTURE SOUTH OF KS. THUS WILL REMOVE
POPS FOR SUN WITH EARLY WORDING FOR SAT.  OTHERWISE NO CHANGES
BEYOND THIS WEEKEND.

OMITT

.ICT...NONE.