654
FNUS73 KLSX 091048
FWSLSX

Spot Forecast for Sioux Passage...St. Louis County Parks Forestry
National Weather Service Saint Louis MO
548 AM CDT Wed Apr 9 2025

Forecast is based on ignition time of 1100 CDT on April 09.
If conditions become unrepresentative, contact the
National Weather Service.

.DISCUSSION...

Cloud cover seen over the area currently will continue through
the day. Despite that, temperatures will rise to around 50 degrees
by ignition, topping out in the upper 60s this afternoon thanks
to southerly winds. These southerly winds are also increasing low-
level moisture compared to days past, leading to greater RH
through the day and the low potential for rainfall this morning.
The better chances for rainfall will remain north of the burn
site, but a brief shower can`t be ruled out between 7am and noon.
At ignition, winds will be southerly to slightly southeasterly,
becoming increasingly southwesterly through the afternoon ahead of
a cold front. This cold front is set to pass over the burn site at
approximately 9-10pm this evening, with winds shifting to out of
the west-northwest with its passage and weakening.

.REST OF TODAY...

Sky/weather.........Mostly cloudy (80-90 percent). Slight chance of
                    rain showers late in the morning.
Temperature.........48 at ignition...Max 67.
RH..................62 percent at ignition...Min 49 percent.
Wind (20 ft)........Winds south at 14 mph at ignition...otherwise
                    South winds 11 to 14 mph with gusts to around
                    28 mph.
Eye level winds.....Winds south at 6 mph at ignition...otherwise
                    South winds up to 6 mph with gusts to around
                    12 mph. Adjustment factor of 0.4 used.
Mixing height.......1500 ft AGL at ignition...otherwise max 2900 ft
                    AGL.
Transport winds.....South 22 to 26 mph.
Smoke dispersal.....Poor /4540 m/s-m/ at ignition. Max...good /9140
                    m/s-m/.

TIME (CDT)      11A 12P 1PM 2PM 3PM 4PM 5PM 6PM 7PM 8PM 9PM 10P
Sky (%).........88  91  89  85  90  88  83  86  75  66  77  66
Weather cov.....SCH SCH
Weather type....RW  RW
Tstm cov........
Temp............48  53  57  59  62  64  65  66  64  62  59  56
RH..............62  58  54  52  50  49  51  49  54  57  64  72
20 FT wind dir..S   S   S   S   S   S   S   S   S   SW  SW  W
20 FT wind spd..14  14  14  13  14  12  11  10  9   9   7   6
20 FT wind gust.25  27  28  26  24  21  19  18  19  20  16  14
Eye lvl wnd dir.S   S   S   S   S   S   S   S   S   SW  SW  W
Eye lvl wnd spd.6   6   6   6   6   6   5   5   4   4   3   3
Eye lvl wnd gst.12  12  13  12  11  10  9   8   9   9   7   6
Mix hgt (kft)...1.5 2.0 2.3 2.4 2.5 2.9 2.4 0.8 0.6 0.5 0.5 0.5
Transp wind dir.S   S   S   S   SW  S   SW  SW  SW  SW  SW  W
Transp wind spd.22  26  26  25  26  23  22  17  15  14  13  12
Vrate kt-ft/1K..29  46  52  53  57  58  46  13  8   6   6   5
Ventrate Cat....PR  FR  FR  FR  FR  FR  FR  PR  PR  PR  PR  PR

$$
Forecaster...Elmore
Requested by...Jason Pratte
Type of request...PRESCRIBED
.TAG 2509433.0/LSX
.DELDT 04/09/25
.FormatterVersion 2.0.0