RSS FeedsIssued by NWS Aberdeen, SD
000 FXUS63 KABR 100155 AFDABR AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ABERDEEN SD 755 PM CST TUE FEB 9 2010 .UPDATE... HAVE UPDATED FORECAST FOR TEMPERATURES TONIGHT. A NEW SNOWFIELD UNDER CLEAR SKIES IS COOLING A LITTLE FASTER THAN EXPECTED. HAVE DROPPED THE JAMES RIVER VALLEY INTO DOUBLE DIGITS BELOW ZERO. REST OF THE FORECAST PACKAGE LOOKS GOOD SO NO OTHER CHANGES WILL BE MADE AT THIS TIME. && .PREV DISCUSSION... .SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT SURFACE HIGH PRESSURE MOVES OVER THE EASTERN PART OF THE CWA TONIGHT. WITH CLEAR SKIES AND FRESH SNOW ON THE GROUND LOOK FOR SIGNIFICANT RADIATIONAL COOLING TONIGHT. WENT LOWER THAN GUIDANCE BY A FEW DEGREES BUT THE JAMES VALLEY COULD EASILY SEE -20 RATHER THAN THE FORECAST -12 ESPECIALLY SINCE DAYTIME HIGHS WERE ONLY IN THE SINGLE DIGITS. IF IT DOES BOTTOM OUT TONIGHT HIGHS WILL NEED TO BE RETHOUGHT FOR WEDNESDAY AS WELL BECAUSE IT WILL BE DIFFICULT TO REBOUND INTO THE TEENS WITH H85 TEMPS IN THE NEGATIVE SINGLE DIGITS. SOLAR RADIATION SEEMS TO BE HAVING LITTLE EFFECT AT THIS TIME OF THE YEAR. MOST OF THE SHORT TERM LOOKS TO BE HIGH AND DRY. HOWEVER A WEAK SHORTWAVE THAT HAS BEEN FAIRLY CONSISTENTLY PORTRAYED IN THE MODELS WILL DROP DOWN ON THURSDAY NIGHT. WE COULD SEE UP TO AN INCH FROM THIS SYSTEM WITH HIGHEST AMOUNTS EAST OF THE SISSETON HILLS. .LONG TERM...FRIDAY THROUGH TUESDAY DECENT AGREEMENT EXISTS BETWEEN EXTENDED GUIDANCE...WITH UPPER FLOW SPLIT TO START THE PERIOD...FOLLOWED BY THE DEEPENING OF THE EAST COAST UPPER TROUGH FOR THE WEEKEND. THAT UPPER TROUGH WILL BE THE DOMINANT FEATURE THROUGH THE FIRST HALF OF NEXT WEEK. CONCERNING PRECIPITATION CHANCES...A COMPACT SHORTWAVE ON NORTHWEST FLOW IS EXPECTED TO DIVE SOUTH OUT OF THE CANADIAN PRAIRIE PROVINCES. WILL SEE DECENT ISENTROPIC FORCING AHEAD...FOLLOWED BY A NORTH/SOUTH ORIENTED 100KT JET STREAK. THE JET STREAK AND A STRONG COLD ADVECTION REGIME TO FOLLOW ARE EXPECTED TO CREATE STRONG NORTHERLY WINDS. AS FOR TEMPERATURES...WILL SEE SOME MODERATION IN H85/925 AIRMASS AND WEAK WARM ADVECTION FRIDAY...BUT ONCE THE EAST COAST LOW DEEPENS...ARMASS TRAJECTORY SWITCHES TO NORTHEAST CANADA AND THE ARCTIC. AT THIS TIME...APPEARS NONE OF THE AIRMASSES GENERATED IN THIS REGIMENT ARE PARTICULARLY INTENSE...WHICH MEANS TEMPERATURES WILL REMAIN BELOW NORMAL BUT NOT EXCESSIVELY. && .AVIATION... A PERSISTENT LAYER OF MVFR CEILINGS IS HANGING IN AROUND KPIR. SATELLITE LOOP SUGGESTS THIS LAYER IS DISSIPATING AND SHOULD MOVE OFF OF THE KPIR AREA IN THE NEXT SEVERAL HOURS. AFTER THAT ALL STATIONS WILL SEE VFR CONDITIONS THROUGH TOMORROW. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ UPDATE...KEEFE SHORT TERM...CONNELLY LONG TERM...WISE AVIATION...KEEFE WEATHER.GOV/ABERDEEN
