FNUS73 KFSD 281436 FWSFSD SPOT FORECAST FOR DES MOINES SNA...MN DNR NATIONAL WEATHER SERVICE SIOUX FALLS SD 936 AM CDT TUE APR 28 2009 IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER SERVICE. .DISCUSSION...AS A SURFACE RIDGE OF HIGH PRESSURE MOVES EAST OF THIS AREA...THE SURFACE WINDS WILL TRANSITION FROM EAST TO SOUTHEAST. AS THE WINDS BECOME SOUTHEAST THIS AFTERNOON...WIND SPEEDS WILL INCREASE TO AROUND 15 MPH. SINCE DRY AIR WILL MIX DOWN FROM ALOFT...DEW POINTS WILL FALL SLIGHTLY AS TEMPERATURES WARM ALLOWING RELATIVE HUMIDITIES TO FALL INTO THE LOWER 30S THIS AFTERNOON. TONIGHT THROUGH WEDNESDAY NIGHT WILL THEN BE MARKED BY UNSETTLED WEATHER. A SERIES OF UPPER AIR DISTURBANCES WILL MOVE THROUGH THIS AREA IN A WAVY PATTERN. THESE DISTURBANCES WILL GIVE GOOD CHANCES FOR WETTING RAINS IN THE FORM OF SHOWERS AND THUNDERSTORMS...WITH WEDNESDAY LIKELY BEING A DAMP DAY MOST LOCATIONS. THE SURFACE COLD FRONT WILL MOVE THROUGH THIS FORECAST AREA WEDNESDAY NIGHT...WITH LINGERING LIGHT PRECIPITATION CHANCES ONLY IN SOUTHWEST MINNESOTA...NORTHWEST IOWA AND EXTREME SOUTHEAST SOUTH DAKOTA ON THURSDAY. FRIDAY COULD SEE A FEW LIGHT SHOWERS ALONG AND SOUTH OF I 90...BUT THOSE CHANCES ARE PRETTY QUESTIONABLE. LIGHT SHOWERS OR NO...THURSDAY AND FRIDAY WILL BE SEASONABLY COOL. .TODAY... MAX TEMPERATURE.....57-62. MIN HUMIDITY........35 PERCENT. TIME (CDT) 10A 11A 12P 1PM 2PM 3PM 4PM 5PM SKY.............CLR MCR MCR PC PC MCR MCR MCR WEATHER TYPE.... TEMP (F)........46 49 51 54 56 58 60 60 RH (%)..........63 54 50 43 40 37 35 35 DEWPOINT (F)....34 33 33 32 32 32 32 32 20 FT WIND DIR..ESE ESE ESE ESE ESE ESE ESE ESE 20 FT WIND SPD..13 13 13 13 14 15 15 15 20 FT WIND GUST.15 15 15 15 20 20 20 20 DISPERSAL INDEX.FR GD GD GD GD GD EX EX CHC OF PCPN (%).0 0 0 0 0 0 0 0 MIX HGT (KFT)...1.2 2.0 2.8 3.6 3.7 3.8 3.9 4.1 TRANSP WIND DIR.ESE ESE ESE ESE ESE ESE ESE ESE TRANSP WIND SPD.21 20 18 16 17 20 21 22 HAINES INDEX....3 3 2 2 2 2 2 2 .TONIGHT... MIN TEMPERATURE.....41-46. MAX HUMIDITY........76 PERCENT. TIME (CDT) 6 PM 8 PM 10 PM MIDNGT 2 AM 4 AM SKY.............MCLEAR PCLDY PCLDY MCLDY MCLDY MCLDY WEATHER COV..... SCTTRD SCTTRD WEATHER TYPE....NONE NONE NONE NONE TSTORM TSTORM TEMP (F)........59 56 51 49 47 46 RH (%)..........36 42 54 61 68 71 DEWPOINT (F)....32 33 35 36 37 37 20 FT WIND......ESE 14 ESE 12 ESE 10 SE 10 SE 10 SE 10 20 FT WIND GUST.20 15 15 15 15 15 DISPERSAL INDEX.EXCEL GOOD POOR POOR POOR POOR CHC OF PCPN (%).0 10 10 10 50 50 .WEDNESDAY... MAX TEMPERATURE.....53-58. MIN HUMIDITY........66 PERCENT. TIME (CDT) 6 AM 9 AM NOON 3 PM SKY.............MCLDY CLOUDY CLOUDY CLOUDY WEATHER COV.....SCTTRD SCTTRD SCTTRD LIKELY WEATHER TYPE....TSTORM TSTORM TSTORM TSTORM TEMP (F)........45 48 52 55 RH (%)..........76 74 69 66 DEWPOINT (F)....38 40 42 44 20 FT WIND......ESE 10G15 ESE 16G25 ESE 18G25 ESE 17G25 DISPERSAL INDEX.POOR FAIR GOOD GOOD CHC OF PCPN (%).50 50 50 60 $$ FORECASTER...BT REQUESTED BY...BRAD BOLDUAN TYPE OF REQUEST...PRESCRIBED .TAG 20090428.DESMO.01/FSD