000 
FXUS63 KUNR 310815
AFDRAP
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY 
NATIONAL WEATHER SERVICE RAPID CITY SD
215 AM MDT THU MAY 31 2001

CURRENT SURFACE MAP HAS WEAK HIGH PRESSURE OVER CENTRAL SOUTH 
DAKOTA...WITH COLD FRONT MOVING INTO EAST MONTANA. SOME LOW 
CLOUDS/FOG OVER EASTERN PART OF CWA...WITH MID CLOUDS COMING IN FROM 
THE WEST. 

COLD FRONT WILL CONTINUE INTO THE WESTERN PART OF THE CWA THIS 
MORNING...AND THROUGH EASTERN PART OF CWA THIS AFTERNOON. SUFFICIENT 
MOISTURE/INSTABILITY AHEAD OF THE FRONT THIS AFTERNOON IN THE 
EASTERN PART OF THE CWA...SO WILL ADD THUNDERSTORMS TO THE FORECAST. 
UPPER LOW CURRENTLY OVER CANADA WILL DROP THROUGH THE EASTERN 
DAKOTAS/MINNESOTA TONIGHT INTO FRIDAY. WITH STEEP LAPSE 
RATES...SHOULD SEE SOME SHOWERS EAST. STRONGER FRONT ALSO DROPS 
THROUGH THE CWA TONIGHT...AND WILL CUT BACK ON TEMPERATURES FOR 
FRIDAY. 

RIDGING OVER THE AREA ON SATURDAY...WITH NEXT TROF MOVING THROUGH 
SATURDAY NIGHT/SUNDAY. AVN/MRF DIFFER FROM LAST NIGHT. INSTEAD OF 
BRINGING AN ELONGATED AND FAST MOVING TROF THROUGH SUNDAY...THEY ARE 
CUTTING OFF A LOW OVER SOUTH DAKOTA FOR SUNDAY/MONDAY. RIDGE THEN 
FORECAST TO REBUILD FOR THE MIDDLE PART OF NEXT WEEK. 

.UNR...NONE.
KC