759 FXUS63 KFSD 230831 AFDFSD AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SIOUX FALLS SD 331 AM CDT MON JUN 23 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 329 AM CDT MON JUN 23 2014 QUIET WEATHER EXPECTED THROUGH TONIGHT WITH FORECAST AREA BETWEEN UPPER TROUGH TO OUR NORTHEAST...AND WEAK LOW LEVEL RIDGE AXIS JUST SOUTHWEST OF THE CWA. A FEW MODELS SHOW SOME VERY LIGHT QPF IN THE MID-LATE AFTERNOON AS A SUBTLE WAVE SLIDES THROUGH WEST-NORTHWEST FLOW ALOFT. CANNOT COMPLETELY RULE OUT A STRAY SHOWER OR STORM AS THE WAVE SLIGHTLY STEEPENS MID LEVEL LAPSE RATES ENOUGH TO GENERATE SOME WEAK INSTABILITY. BUT WITH LITTLE SUPPORT FROM HIGH-RES MODELS HAVE CHOSEN TO LEAVE THE FORECAST DRY FOR NOW. SHOULD SEE FAVORABLE MIXING IN RELATIVELY UNIDIRECTIONAL WEST-NORTHWEST FLOW...SO HAVE CONTINUED TO SIDE WITH WARMER GUIDANCE HIGHS A DEGREE OR TWO EITHER SIDE OF 80...WITH AFTERNOON DEW POINTS MIXING DOWN TO NEAR 50 WEST OF THE JAMES RIVER WHERE RAINFALL HAS BEEN MUCH MORE SPARSE OVER THE PAST WEEK OR SO. EASTERN AREAS SHOULD ALSO SEE DEW POINTS DROP OFF A BIT IN THE AFTERNOON...THOUGH WILL HOLD IN MID-UPPER 50S THERE GIVEN RECENT HEAVY RAINS. SHOULD BE A FAIRLY COMFORTABLE NIGHT FOR LATE JUNE...WITH LOWS IN THE MID 50S TO NEAR 60. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 329 AM CDT MON JUN 23 2014 THE MAJORITY OF TUESDAY IS EXPECTED TO BE DRY ACROSS THE AREA. HOWEVER...WE'LL STILL HAVE SLIGHT TO LOW CHANCE POPS ACROSS THE AREA BY THE AFTERNOON HOURS. THE CWA WILL BE TEMPORARILY CAUGHT IN NORTHWESTERLY FLOW ALOFT DUE TO AN UPPER DISTURBANCE DROPPING SOUTHEAST OUT OF CANADA. THIS SYSTEM WILL KEEP RICH LOW-LEVEL MOISTURE WELL SOUTHWEST OF THE AREA DURING THE DAYTIME HOURS. HIGHEST PROBABILITY OF A FEW THUNDERSTORMS WILL BE FOUND IN THE FAR NORTH AND NORTHEAST CWA WHERE BETTER SYNOPTIC LIFT WILL BE FOUND ALONG A NARROW AXIS OF 500-1000 J/KG. AREAS OF THE EXTREME WESTERN ZONES COULD SEE A FEW SPOTTY SHOWERS OR ISOLATED THUNDERSTORMS ALONG LEADING EDGE OF HIGHER THETA-E AIR. AS THE AFOREMENTIONED TROUGH SHIFTS EASTWARD INTO THE GREAT LAKES...LOW LEVEL FLOW WILL TURN SOUTHWESTERLY ALLOWING RICH LOW LEVEL MOISTURE TO STREAM NORTHEAST INTO THE REGION. NOCTURNAL LLJ MAY BE STRONG ENOUGH TO PRODUCE CONVECTION ALONG THE RETREATING THETA-E AXIS TUESDAY NIGHT...WITH HIGHEST CHANCES FOR CONVECTION ALONG AND SOUTH OF THE MO RIVER. UNSETTLED CONDITIONS ARE ANTICIPATED WEDNESDAY AND THURSDAY AS MINOR SHORTWAVES MOVE THROUGH THE AREA. SEVERE WEATHER CHANCES APPEAR LOW IN THE MIDDLE OF THE WEEK...BUT BRIEF PERIOD OF INCREASED MID-LEVEL FLOW ON WEDNESDAY AFTERNOON/NIGHT COMBINED WITH 1500-2000 J/KG CAPE COULD LEAD TO A FEW STRONGER STORMS IN THE AFTERNOON/EVENING. MEDIUM RANGE MODELS CONTINUE TO SUGGEST UPPER TROUGHING WILL DEEPEN ACROSS THE WESTERN CONUS HEADING INTO NEXT WEEKEND. THE SLIGHTLY MORE MERIDIONAL FLOW WILL BEGIN TO PUSH TEMPERATURES ABOVE NORMAL...BUT ALSO INDUCE HIGHER LEVELS OF SHEAR AND INSTABILITY BY FRIDAY AND SATURDAY. WILL NEED TO CONTINUE TO MONITOR THE END OF THE WEEK (FRIDAY AND SATURDAY) FOR THE POTENTIAL OF SEVERE STORMS AND INCREASED CHANCES OF HEAVY RAIN IN THE LOCAL AREA. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 658 PM CDT SUN JUN 22 2014 VFR THROUGH THE PERIOD. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ SHORT TERM...JH LONG TERM...DUX AVIATION...08