481
FNUS73 KDMX 021239
FWSDMX

Spot Forecast for Rathbun Lake Prescribed Fire...U.S. Army Corps of Engineers
National Weather Service Des Moines IA
739 AM CDT Wed Sep 2 2026

Forecast is based on ignition time of 0800 CDT on September 02.
If conditions become unrepresentative...contact the National Weather
Service.

An initial observation at ignition and a mid burn observation are required.

Please relay them to the National Weather Service for each prescribed burn.

...HEAT ADVISORY IN EFFECT UNTIL 7 PM CDT THURSDAY...

.DISCUSSION...

Sunny, warm, and humid today with a high around 95 and relative
humidity this afternoon remaining above 45%. This morning wind
will be variable and a few erratic gusts to 20 mph are possible
as outflow wind from thunderstorms in northern Iowa stretches
south. Otherwise, wind will be from the southwest at 10-15 mph
gusts 15-20 mph.


.REST OF TODAY...

Sky/weather.........Sunny (10-20 percent).
Max temperature.....Around 94.
Min humidity........46 percent.
Wind (20 ft)........Southwest winds 8 to 12 mph.
Mixing height.......5700 ft AGL.
Transport winds.....Southwest 12 to 20 mph.
Smoke dispersal.....Poor (5100 knot-ft) early in the morning
                    increasing to good (90800 knot-ft) in the
                    afternoon.
GFDI................0.

TIME (CDT)      8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........23  15  6   8   19  14  10  19  9   12
Weather cov.....
Weather type....
Tstm cov........
Temp............76  80  84  86  89  91  92  93  93  93
RH..............76  69  63  59  54  50  49  46  46  46
20 FT wind dir..SW  SW  SW  SW  SW  SW  SW  SW  SW  SW
20 FT wind spd..8   10  12  12  12  12  12  12  10  9
20 FT wind gust.13  20  20  20  20  20  20  20  18  16
Mix hgt (kft)...0.5 0.6 1.2 1.7 2.6 3.5 4.4 5.2 5.7 4.4
Transp wind dir.SW  SW  SW  SW  SW  SW  SW  SW  SW  SW
Transp wind spd.12  13  15  17  18  18  20  20  18  16
GFDI............0   0   0   0   0   0   0   0   0   0
Smoke Dispersal.5   7   16  26  41  56  74  88  91  62
Smoke Cat.......PR  PR  PR  PR  FR  FR  GD  GD  GD  GD

.TONIGHT...

Sky/weather.........Mostly clear (15-25 percent).
Min temperature.....Around 76.
Max humidity........69 percent.
Wind (20 ft)........South winds 6 to 8 mph.
Mixing height.......400 ft AGL.
Transport winds.....South 12 to 15 mph.
Smoke dispersal.....Poor (4500 knot-ft).
GFDI................0.

TIME (CDT)      6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........19  19  28  10  7   10  11  18  13  8   11  8
Weather cov.....
Weather type....
Tstm cov........
Temp............92  90  88  86  84  83  82  82  82  81  79  79
RH..............49  52  55  57  61  63  63  63  63  65  69  69
20 FT wind dir..SW  S   S   S   S   S   S   S   S   S   S   S
20 FT wind spd..7   6   8   8   8   8   7   7   7   7   7   7
20 FT wind gust.15  15  16  16  16  16  15  16  15  15  15  15
Mix hgt (kft)...2.0 0.8 0.5 0.5 0.5 0.4 0.5 0.5 0.5 0.5 0.5 0.5
Transp wind dir.S   S   S   S   S   S   S   S   S   S   SW  SW
Transp wind spd.13  12  12  12  12  13  13  14  14  15  15  15
GFDI............0   0   0   0   0   0   0   0   0   0   0   0
Smoke Dispersal.22  8   5   5   5   5   5   6   6   6   6   6
Smoke Cat.......PR  PR  PR  PR  PR  PR  PR  PR  PR  PR  PR  PR

.THURSDAY...

Sky/weather.........Sunny (10-20 percent).
Max temperature.....Around 92.
Min humidity........54 percent.
Wind (20 ft)........Southwest winds 7 to 10 mph.
Mixing height.......7000 ft AGL.
Transport winds.....Southwest 14 to 16 mph.
Smoke dispersal.....Poor (5400 knot-ft) early in the morning
                    increasing to good (97700 knot-ft) in the
                    afternoon.
GFDI................0.

TIME (CDT)      6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........10  7   5   7   14  4   18  11  9   13  26  17
Weather cov.....
Weather type....
Tstm cov........
Temp............78  76  79  80  82  85  88  89  90  90  91  90
RH..............71  76  72  72  69  63  57  56  54  54  54  56
20 FT wind dir..S   S   SW  SW  SW  SW  SW  SW  SW  S   S   S
20 FT wind spd..7   7   7   8   9   9   9   10  10  10  9   9
20 FT wind gust.15  15  16  16  17  17  17  17  17  17  16  16
Mix hgt (kft)...0.5 0.4 0.6 1.3 1.8 2.7 3.7 4.8 6.7 7.0 5.9 6.3
Transp wind dir.SW  SW  SW  SW  SW  SW  SW  SW  SW  SW  S   S
Transp wind spd.14  14  14  15  15  15  15  15  16  16  14  14
GFDI............0   0   0   0   0   0   0   0   0   0   0   0
Smoke Dispersal.6   5   7   17  24  35  48  63  93  98  71  76
Smoke Cat.......PR  PR  PR  PR  PR  PR  FR  GD  GD  GD  GD  GD

$$
Forecaster...Hagenhoff
Requested by...Scott Frieden
Type of request...PRESCRIBED
.TAG 2621086.0/DMX
.DELDT 09/02/26
.FormatterVersion 2.0.0
.EMAIL scott.a.frieden@usace.army.mil