850 
FXUS63 KFSD 040731
AFDFSD

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA 
NATIONAL WEATHER SERVICE SIOUX FALLS SD
230 AM CDT MON OCT 4 1999

MAIN CONCERN THIS FORECAST IS TEMPERATURES.  LATEST SURFACE ANALYSIS 
SHOWS HIGH PRESSURE FROM SERN MN TO ERN NE/KS...WITH LIGHT SLY FLOW 
OVER MOST OF CWA.  HIGH SAGS SEWD TODAY...WHILE MODELS AGREE IN 
BRINGING WEAK COOL FRONT/TROUGH INTO CENTRAL SD BY THIS EVENING... 
AND ACROSS CWA BY MIDDAY TUESDAY.  TIME SECTIONS FROM ETA/NGM 
SHOWING VERY DRY ATMOSPHERE THROUGH FORECAST PERIOD...SO DO NOT 
EXPECT MUCH IN THE WAY OF CLOUD COVER...MAYBE SOME MID/HIGH CLOUDS 
WITH PASSING TROUGH/ASSOCIATED 300MB JET STREAK LATER TONIGHT INTO 
TUESDAY...MAINLY OVER NORTHERN CWA.  

SLY TO SWLY SFC FLO PREVAILS OVER CWA TODAY...WITH SWLY-WLY 850MB 
FLO PROVIDING A SIGNIFICANT WARMUP WITH 850MB TEMPS FORECAST TO WARM 
6-8 DEG C THROUGH THE DAY.  DECENT MIXING SHOULD HELP MOST AREAS 
REACH THE 60S TODAY...WITH POTENTIAL FOR SWRN COUNTIES TO TOP 70.  
WILL GO FAIRLY CLOSE TO FWC GUIDANCE...WHICH IS ALSO CONSISTENT WITH 
GOING FORECAST.  WITH WARMUP COMES SLIGHT INCREASE IN DEWPOINTS... 
WHICH ALONG WITH WINDS STAYING UP SOME OVERNIGHT...WILL ALLOW LOWS 
TO REMAIN ABOVE FREEZING...UPPER 30S TO LOWER 40S EXPECTED MOST 
AREAS.  AFOREMENTIONED TROUGH BRINGS SLIGHT COOLING TO 850MB TEMPS 
FOR NORTHERN CWA ON TUESDAY...WITH WARMEST AIR FOUND ACROSS THE 
SOUTH AROUND KSUX.  THINK GUIDANCE MAY BE A TOUCH TOO WARM FOR 
TUESDAY AND WILL ADJUST ACCORDINGLY. 

.FSD...NONE.
 HAMEN