271 
FXUS63 KUNR 260936
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
335 AM MDT TUE OCT 26 2004

.DISCUSSION...CURRENT SURFACE ANALYSIS HAS HIGH PRESSURE OVER THE 
GREAT LAKES AREA WITH A WEAK TROUGH IN THE LEE OF THE CENTRAL 
ROCKIES. WINDS ARE PREDOMINATELY OUT OF THE SOUTH TO SOUTHEAST AND 
LIGHT. TEMPERATURES HAVE REMAINED FAIRLY MILD OVERNIGHT...IN THE 30S 
AND 40S.

FORECAST AREA REMAINS UNDER BACKSIDE OF UPPER RIDGE WITH FAST 
SOUTHWEST FLOW ALOFT. A WEAK SHORTWAVE CURRENTLY IN UTAH WILL CROSS 
WESTERN PORTIONS OF THE FORECAST AREA THIS MORNING...SO WILL 
INTRODUCE SOME LOW POPS ACROSS NE WY AND NW SD. TEMPS WILL BE A 
LITTLE WARMER TODAY...AS SOUTHERLY FLOW CONTINUES. WITH MOIST 
SOUTHERLY FLOW CONTINUING INTO TONIGHT...PATCHY FOG MAY DEVELOP 
ACROSS SOUTHERN PORTIONS OF SOUTH DAKOTA EARLY WEDNESDAY MORNING. 

ANOTHER WEAK IMPULSE MOVES THROUGH THE AREA ON WEDNESDAY. ENOUGH 
MOISTURE AND INSTABILITY AROUND TO WARRANT A CHANCE OF A SHOWER OR 
THUNDERSTORM OVER THE BLACK HILLS AREA. THURSDAY WILL SEE A CHANCE 
OF SHOWERS AND THUNDERSTORMS AGAIN...AS WEST COAST TROUGH CONTINUES 
TO EJECT WEAK SHORTWAVES INTO THE NORTHERN PLAINS.

SIGNIFICANT STORM SYSTEM PROGGED FOR THURSDAY NIGHT AND FRIDAY IS 
STILL ON TRACK FOR THIS AREA. TEMPS STILL LOOK WARM ENOUGH FOR THIS 
SYSTEM TO PRODUCE MAINLY RAIN. STILL COULD SEE SOME SNOW ACROSS 
NORTHEAST WYOMING AND THE HIGHER ELEVATIONS OF THE BLACK HILLS 
FRIDAY AFTERNOON AND EVENING. SYSTEM PULLS OUT OF THE AREA ON 
SATURDAY MORNING.

A STRONG COLD FRONT LOOKS LIKE IT WILL MAKE ITS WAY THROUGH THE AREA 
ON SATURDAY NIGHT...GIVING THE WESTERN PORTIONS OF THE FORECAST AREA 
ANOTHER QUICK SHOT OF SNOW. TEMPS LOOK LIKE THEY WILL BE SHARPLY 
COOLER FOR SUNDAY INTO THE BEGINNING OF NEXT WEEK.

&&

.AVIATION...SCT SHWRS OVR FAR NW SD AND WRN ND AT 08Z SHLD MOVE NE 
AND OUT OF THE AREA BY 12Z. THESE SHOWERS MAY PRODUCE LOCAL MVFR 
CONDS DUE TO CLOUDS THRU 12Z. THERE WILL BE ISOLATED AREAS OF IFR 
CONDS DUE TO FOG AND LOW CLDS...MAINLY ACRS NE WY AND NWRN SD THRU 
12Z.

BEYOND 12Z...SW FLOW WILL CONTINUE ACROSS THE REGION TODAY AND 
TONIGHT. VFR CONDS ARE EXPECTED THROUGH THE FORECAST PERIOD WITH 
CLOUDS MAINLY IN THE 10000 TO 15000 FT RANGE.

&&

.UNR...WATCHES/WARNINGS/ADVISORIES...
.SD...NONE.
.WY...NONE.

$$
 
RUDGE/LJC