231 FXUS63 KFSD 021654 AFDFSD AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SIOUX FALLS SD 1054 AM CST SUN MAR 2 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 326 AM CST SUN MAR 2 2014 WITH SNOW OUT OF THE PICTURE...THE OBVIOUS FEATURE FOR TODAY IS THE RECORD COLD. ARCTIC AIR AND SNOW COVER PRETTY MUCH GUARANTEES SOME DAILY RECORD LOW MAXIMUMS WITH ACTUAL HIGHS AT OR A LITTLE BELOW ZERO. ENOUGH WIND WILL REMAIN TO KEEP THE WIND CHILL WARNING AND ADVISORY THROUGH THIS MORNING AND THE ADVISORY EAST OF THE JAMES RIVER THROUGH THE DAY. WILL KEEP THESE HIGHLIGHTS AS WE HAVE HAD THEM...USING THE DISCRETION THAT WHILE WIND CHILLS WILL TECHNICALLY STAY AT ADVISORY LEVELS INTO TONIGHT...AT LEAST IN THE EAST...WINDS WILL GET QUITE LIGHT...BUT THIS CAN BE REVISITED DURING THE DAY. PATCHY MID CLOUDS MOVING OVER THE AREA SHOULD GENERALLY DECREASE...THOUGH SOME MORE MAY MOVE OVER THE SOUTHWEST CORNER OF THE AREA LATER. FOR TONIGHT...TEMPERATURES WILL DROP TO QUITE COLD LEVELS AGAIN...10 TO 20 BELOW...WITH THOSE LIGHT WINDS...ALTHOUGH SOME LEVELING OFF AND A LITTLE WARMING SHOULD TAKE PLACE WEST LATE TONIGHT AS WEAK LOW LEVEL WARM ADVECTION STARTS. ALSO...CLOUDS ARE EXPECTED TO INCREASE AGAIN FROM THE WEST LATE TONIGHT...THOUGH NO PRECIPITATION SHOULD THREATEN WITH LITTLE OR NO LIFT AND DRY AIR BELOW THE MID LEVELS. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 326 AM CST SUN MAR 2 2014 BIGGEST CHALLENGE FOR MONDAY IS HOW MUCH WE CAN WARM WITH FRESH SNOW COVER. GFS AND ECMWF SHOW FAIR AMOUNT OF WARMING INTO OUR WESTERN CWA DURING THE AFTERNOON AND QUESTION IS HOW MUCH OF THAT WILL TRANSLATE TO THE SURFACE. GIVEN THE FRESH SNOW...NOT ONLY IN PLACE BUT UPSTREAM...ALONG WITH SOUTHEASTERLY LOW LEVEL FLOW BENEATH THE INVERSION...OPTED TO STICK CLOSER TO COOLER GUIDANCE VALUES. THIS GIVES UPPER SINGLE DIGITS IN OUR EAST AND UPPER TEENS IN THE FAR SOUTHWEST...BUT POTENTIAL IS THERE FOR READINGS ABOUT 5-7 DEGREES WARMER IF BOUNDARY LAYER MIXING IS DEEPER THAN ANTICIPATED. MONDAY NIGHT WAVE LOOKS TO TRACK A LITTLE FARTHER NORTHEAST THAN EARLIER RUNS...SO HAVE TRIMMED BACK POPS THERE TO JUST A SLIGHT CHANCE IN OUR FAR NORTHEAST. BIGGER CHANGE IN PRECIPITATION CHANCE IS FOR TUESDAY/TUESDAY NIGHT PERIOD THOUGH. 02/00Z RUNS OF BOTH GFS AND ECMWF HAVE TRENDED FASTER WITH THE STRONGER WAVE TRACKING ACROSS THE REGION...RESULTING IN LIGHT SNOW ZIPPING THROUGH DURING THE DAY ON TUESDAY...FOLLOWED BY DRYING CONDITIONS TUESDAY NIGHT. MOISTURE AND LIFT ALSO FOCUSED A LITTLE FARTHER NORTHEAST THAN WITH PREVIOUS TUESDAY NIGHT WAVE...SO HAVE HIGHEST POPS NORTHEAST OF KMHE-KSLB LINE WITH JUST SLIGHT CHANCE INTO THE MISSOURI VALLEY. STILL LOOKS LIKE RELATIVELY LIGHT AMOUNTS...AROUND AN INCH OR LESS FROM EAST CENTRAL SD INTO SOUTHWEST MN. TEMPS JUST SLIGHTLY WARMER THAN MONDAY...WITH HIGHS GENERALLY MID TEENS TO LOWER 20S. LONGER RANGE WEDNESDAY THROUGH SATURDAY STILL PLAGUED BY LACK OF MODEL CONSENSUS REGARDING TIMING/STRENGTH OF MID-UPPER LEVEL WAVES IN FAST WEST-NORTHWEST FLOW. FAIR AGREEMENT IN KEEPING DRY WEATHER IN OUR AREA THROUGH WEDNESDAY AS SHARPER WAVE SLIDES THROUGH WESTERN NEBRASKA AND KEEPS PRECIP CHANCE FOCUSED SOUTHWEST OF US. WEDNESDAY NIGHT AND THURSDAY SEES A STRONGER TROUGH MOVING ACROSS THE CANADIAN PRAIRIES...WITH SOME QUESTION HOW FAR SOUTH INTO THE NORTHERN PLAINS ANY WEAKER ENERGY WILL TRACK. OPTING TO LEAVE THESE PERIODS ON THE DRIER SIDE AS WELL...WITH JUST SOME SMALL POPS IN OUR FAR NORTH. LOOKS A LITTLE BETTER FOR SOME ENERGY SLIDING FARTHER SOUTH INTO OUR AREA THURSDAY NIGHT OR FRIDAY...THOUGH STILL SOME TIMING DIFFERENCES SO WILL KEEP POPS ON THE LOW SIDE IN 20-30 PERCENT RANGE...FOLLOWED WITH DRYING BY SATURDAY. AS FAR AS TEMPERATURES...THURSDAY CONTINUES TO LOOK LIKE WARMEST DAY...THOUGH DIFFERENCES IN TIMING NOTED ABOVE LEAD TO COOLER GFS THAN PREVIOUS RUNS/CONSENSUS. WILL STICK WITH WARMER TREND OF HIGHS IN 30S/40S FOR NOW...BUT THIS REMAINS A PERIOD OF UNCERTAINTY. FRIDAY/SATURDAY STILL LOOK GOOD WITH COOLER HIGHS IN THE 20S AND 30S...THOUGH STILL RELATIVELY MILD COMPARED TO THE START OF THE WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1053 AM CST SUN MAR 2 2014 VFR CONDITIONS EXPECTED THROUGH THE PERIOD. LIGHT NORTHERLY WINDS TODAY WILL TRANSITION TO LIGHT SOUTHERLY TOMORROW WITH INCREASING HIGH CLOUDS. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...WIND CHILL ADVISORY UNTIL 6 PM CST THIS EVENING FOR SDZ061-062- 066-067-070-071. WIND CHILL ADVISORY UNTIL NOON CST TODAY FOR SDZ050-057>060- 063>065-068-069. WIND CHILL WARNING UNTIL NOON CST TODAY FOR SDZ038>040-052>056. WIND CHILL ADVISORY UNTIL 6 PM CST THIS EVENING FOR SDZ039-040- 055-056. MN...WIND CHILL ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ098. WIND CHILL WARNING UNTIL NOON CST TODAY FOR MNZ071-072-080-081- 089-090-097. WIND CHILL ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ071-072- 080-081-089-090-097. IA...WIND CHILL ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ001-012- 020-031. WIND CHILL WARNING UNTIL NOON CST TODAY FOR IAZ002-003-013-014- 021-022-032. WIND CHILL ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ002-003- 013-014-021-022-032. NE...WIND CHILL ADVISORY UNTIL 6 PM CST THIS EVENING FOR NEZ013-014. && $$ SHORT TERM... LONG TERM...JH AVIATION...CHENARD