999 
FXUS63 KTOP 172102
AFDTOP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
300 PM CST WED MAR 17 1999

...TEMPERATURES THE MAIN FORECAST CONCERN THROUGH THURSDAY...THEN 
THE CHANCES FOR RAIN ON FRIDAY...

TRACK RECORD OF MODELS IN HANDLING SOUTHWEST LOW THE PAST SEVERAL 
DAYS LESS THAN STELLAR.  AVN HAS BEEN MOST CONSISTENT WITH NORTHERN 
TRACK OF LOW.  MEANWHILE NGM/ETA HAVE FLIP/FLOPPED WITH THEIR 
POSITIONS FARTHER SOUTH FROM ONE RUN TO THE NEXT...AND ALL OF THE 
MODELS HAVE BEEN TOO FAST. PER NCEP DISCUSSION...IT APPEARS THE LOW 
MUST EVENTUALLY LIFT OUT TO THE NORTHEAST. THUS, AT THIS POINT WILL 
GO MORE WITH THE AVN MODEL AS IT IS FARTHER NORTH BUT STILL THE 
SLOWEST OF THE MODELS. 

IN THE SHORT TERM...HIGH PRESSURE RIDGE BUILDING INTO CENTRAL PLAINS 
SHOULD KEEP SKIES CLEAR OVER CWA TONIGHT.  SURFACE PLOT SUGGESTING 
DEWPOINTS WILL BE IN THE 20-25 DEGREE RANGE OVERNIGHT SO FAIRLY COLD 
TEMPERATURES POSSIBLE. HOWEVER...BOUNDARY LAYER WINDS ALSO INDICATED 
TO HOLD IN 15-20 MPH RANGE WHICH SHOULD PROVIDE ENOUGH MIXING TO 
KEEP TEMPERATURES FROM FALLING INTO THE LOWER 20S WITH MOST LOWS 
LIKELY TO BE IN THE UPPER 20S TO AROUND 30.  

FOR THURSDAY...MODELS ARE SUGGESTING WILL STILL SEE QUITE A BIT OF 
SUNSHINE OVER CWA ALTHOUGH MAY SEE AN INCREASE IN HIGH CLOUDS DURING 
THE AFTERNOON. HOWEVER...IF TEMPERATURES START OUT IN THE UPPER 20S 
TO AROUND 30, THE FWC/NGM TEMPERATURES LOOK A LITTLE TOO WARM WHILE 
THE FAN/AVN NUMBERS LOOK TOO COOL. A COMPROMISE BETWEEN THE TWO 
LOOKS BEST WITH HIGHS MAINLY IN THE 50 TO 55 DEGREE RANGE. 

WILL GO WITH 20 PERCENT POPS EAST CENTRAL ZONES LATE THURSDAY NIGHT 
AS UPPER LOW WILL HOPEFULLY FINALLY BE GETTING CLOSE ENOUGH FOR 
CHANCE OF RAIN BY THAT TIME...AND THEN WENT WITH 30-50 PERCENT POPS 
FROM NORTH TO SOUTH ACROSS CWA ON FRIDAY. WITH CLOUDS AND POSSIBLE 
RAIN ON FRIDAY...WILL GO WITH COOLER FAN NUMBERS. 

.TOP...NONE.

PB