FNUS73 KABR 151236 FWSABR Spot Forecast for Dismal Swamp...FWS National Weather Service Aberdeen SD 736 AM CDT Wed Apr 15 2026 Forecast is based on ignition time of 1000 CDT on April 15. If conditions become unrepresentative...contact the National Weather Service. .DISCUSSION... A Dense Fog Advisory is in effect until 9 AM CDT this morning, and pockets of dense fog are expected to dissipate over the next couple of hours this morning. Warmer and drier air moves in this afternoon, with highs reaching the low 70s (roughly 15 degrees above normal for mid-April) and afternoon humidity dropping to between 30 and 35 percent. Southerly winds remain light this afternoon, around 5 miles per hour gusting to 10 miles per hour. Gusty conditions return on Thursday, with southerly winds increasing to 25 to 30 miles per hour by the afternoon. Another warm day (highs in the upper 70s to perhaps touching 80 degrees) will enable minimum afternoon humidity dropping to between 25 and 30 percent. The wind and humidity combination leads to elevated fire weather concerns Thursday afternoon, and the Grassland Fire Danger Index will reach the High category. Winds will shift Thursday night, turning briefly to the east before solidifying in a northerly direction early Friday morning. Once this shift occurs, wind speeds will increase once again, reaching 15 to 20 miles per hour sustained and gusting to 30 miles per hour by Friday afternoon. .REST OF TODAY... Sky/weather.........Partly sunny (20-30 percent) then becoming mostly sunny (10-20 percent). CWR.................0 percent. Chance of pcpn......0 percent. Chance of lightning.1 percent. Max temperature.....Around 73. Min humidity........34 percent. Wind (20 ft)........South winds 5 to 7 mph. Mixing height.......1100-8800 ft agl. Transport winds.....Southwest 8 to 12 mph increasing to 13 to 14 mph late in the afternoon. Smoke dispersal.....Poor (7900 knot-ft) early in the morning increasing to very good (101700 knot-ft) in the afternoon. TIME (CDT) 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........26 5 2 6 21 18 24 15 Weather cov..... Weather type.... Tstm cov........ Chc of pcpn (%).0 0 0 0 0 0 0 0 Chc of ltng (%).0 0 0 0 0 0 0 0 Temp............48 59 64 67 68 70 71 71 RH..............75 57 46 43 42 36 34 34 20 FT wind dir..S S S S S S S S 20 FT wind spd..6 5 6 6 6 7 7 6 20 FT wind gust.8 10 12 12 12 12 12 12 Mix hgt (kft)...1.1 1.8 2.2 3.4 5.7 7.7 8.5 8.8 Smoke Dispersal.PR PR PR PR FR GD VGD GD .TONIGHT... Sky/weather.........Mostly clear (5-15 percent). CWR.................0 percent. Chance of pcpn......0 percent. Chance of lightning.0 percent. Min temperature.....Around 46. Max humidity........83 percent. Wind (20 ft)........Southeast winds 6 to 8 mph. Mixing height.......400-8400 ft agl. Transport winds.....Southwest 9 to 12 mph shifting to the south 9 to 16 mph early in the evening. Smoke dispersal.....Good (83700 knot-ft) early in the evening decreasing to poor (4000 knot-ft) late in the night. TIME (CDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM Sky (%).........13 5 15 15 8 7 7 7 5 7 5 8 Weather cov..... Weather type.... Tstm cov........ Chc of pcpn (%).0 0 0 0 0 0 0 0 0 0 0 0 Chc of ltng (%).0 0 0 0 0 0 0 0 0 0 0 0 Temp............71 69 64 61 59 57 55 53 51 49 48 48 RH..............34 36 43 48 53 57 61 64 68 74 77 77 20 FT wind dir..S S SE SE SE SE SE S S S S S 20 FT wind spd..6 6 6 6 6 7 7 8 8 8 8 8 20 FT wind gust.12 10 10 12 13 13 14 15 14 14 14 15 Mix hgt (kft)...8.4 4.9 1.2 0.5 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Smoke Dispersal.GD PR PR PR PR PR PR PR PR PR PR PR .THURSDAY... Sky/weather.........Mostly sunny (5-15 percent). CWR.................1 percent. Chance of pcpn......0 percent. Chance of lightning.2 percent. Max temperature.....Around 79. Min humidity........27 percent. Wind (20 ft)........South winds 8 to 17 mph increasing to 17 to 20 mph in the afternoon. Mixing height.......300-8300 ft agl. Transport winds.....South 14 to 22 mph increasing to southwest 24 to 33 mph in the late morning and afternoon. Smoke dispersal.....Poor (4100 knot-ft) early in the morning increasing to good (98700 knot-ft) in the afternoon increasing to excellent (152300 knot-ft) late in the afternoon. TIME (CDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........9 15 8 6 3 3 4 4 3 3 2 6 Weather cov..... Weather type.... Tstm cov........ Chc of pcpn (%).0 0 0 0 0 0 0 0 0 0 0 0 Chc of ltng (%).0 0 0 0 0 0 0 0 0 0 0 0 Temp............47 46 49 54 60 65 70 74 77 78 79 79 RH..............76 83 77 66 53 45 36 32 29 28 27 27 20 FT wind dir..S S S S S S S S S S S S 20 FT wind spd..8 9 10 13 15 17 18 20 20 20 18 17 20 FT wind gust.15 16 17 20 22 24 25 26 28 28 26 24 Mix hgt (kft)...0.3 0.3 0.5 0.8 1.4 2.5 3.5 4.5 6.2 7.8 8.3 6.6 Smoke Dispersal.PR PR PR PR PR FR GD GD EXL EXL EXL EXL $$ Forecaster...BC Requested by...Millette Type of request...PRESCRIBED .TAG 2610397.0/ABR .DELDT 04/15/26 .FormatterVersion 2.0.0 .EMAIL phil_millette@fws.gov