000 
FXUS63 KFSD 272000
AFDFSD

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA  
NATIONAL WEATHER SERVICE SIOUX FALLS SD
300 PM CDT TUE MAY 27 2003

MAIN CONCERNS FOR THIS PACKAGE WILL BE CHANCE FOR THUNDER TONIGHT 
AND AGAIN ON THURSDAY...OTHERWISE MAINLY TEMPS.

WEAK CONVERGENCE OCCURRING OVER CENTRAL SOUTH DAKOTA...WITH BETTER 
CONVERGENCE OVER ND AND NE SD AND ALSO OVER THE PANHANDLE OF NE. 
ALSO NOTED VIA THE WATER VAPOR THAT THE BETTER UPPER LEVEL SUPPORT 
IN THESE SAME GENERAL AREAS.

WITH INCOMING BOUNDARY AND NICE POOLING OF DEW POINTS...A MILD NIGHT 
EXPECTED WITH PRETTY MUCH EVERYONE IN THE 50S. WOULDNT BE SURPRISED 
IF A 60 OR 61 OCCURRED OVER NORTHWEST IOWA. WILL CONTINUE LOW POPS 
FOR EVERYONE AS WEAK AXIS OF INSTABILITY PASSES. LAPSE RATES 6.5 C 
OR LESS...SFC LIS 0 TO -2...SHEAR LOW AND PRETTY MUCH NO CAPE SO 
EXPECT MAINLY ISOLATED THUNDER.

FOR WEDNESDAY...AS WAVE PASSES...WILL SWING WINDS AROUND TO THE 
NORTH BUT CLOUDS WILL CLEAR AND EVEN THOUGH COOLER TEMPS COMING IN 
FROM THE NORTH...GOOD MIXING WILL ALLOW FOR NICE WARMING...ALTHOUGH 
BREEZY. 

WEAK HIGH PRESSURE MOVES QUICKLY ACROSS CWA WEDNESDAY NIGHT...WITH 
RETURN FLOW SETTING UP ON THURSDAY. PLAN ON HAVING WARMEST TEMPS 
THIS DAY...RANGING FROM NEAR 90 CENTRAL SD TO LOW 80S SOUTHWEST MN. 
ALSO LOOKING AT ANOTHER WAVE PASSING THROUGH WITH MORE FAVORABLE 
PARAMETERS FOR SVR WX...BUT +11 AT 700MB AND A CIN OF 120-160 JKG 
COULD PROVE TO BE A LIMITING FACTOR...SO WILL ONLY HAVE LOW POPS.

IN THE LATTER PERIODS...LOOKING AT A FAIRLY CONSISTENT MODEL OUTPUT 
BETWEEN THE ECMWF/CANADIAN/MRF INTO THE WEEKEND. WHILE NOT INITIALLY 
BUYING INTO THE VERY COLD AIR DROPPING DOWN ON THE AVN LATE FRIDAY 
INTO SATURDAY...WILL TREND BELOW GUIDANCE DURING THIS TIME FRAME. 
OTHERWISE...NOT A LOT HAPPENING SUNDAY AND MONDAY WITH NORMAL TO 
ABOVE NORMAL TEMPERATURES EXPECTED. HAVE ADDED A CHANCE FOR TSRA ON 
TUESDAY TO CONFORM WITH SURROUNDING OFFICES AS MRF HAS FRONT MOVING 
THROUGH LATE MONDAY INTO TUESDAY.

.FSD...NONE

$$

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