040
FNUS73 KLSX 221552
FWSLSX

Spot Forecast for 107 Prairie - MTSP...Department of Natural Resources
National Weather Service Saint Louis MO
952 AM CST Thu Jan 22 2026

Forecast is based on ignition time of 0900 CST on January 22.
If conditions become unrepresentative, contact the
National Weather Service.

.DISCUSSION...
Dry conditions and near average temperatures are expected today. Around
ignition time, winds will become westerly with RH also falling
below 60 percent, reaching the 30s percent this afternoon. Mixing
heights will be rising from 750 ft AGL at ignition time to between
3250 to 3750 ft AGL this afternoon, helping smoke dispersal improve
from poor this morning to good this afternoon.

Tonight a cold front will pass through the region, veering winds to
northerly and strengthening them. Steady northerly winds will continue
on Friday sustained 12 to 16 mph and ushering bitterly cold air into
the area. Widespread accumulating snow will arrive Saturday, lasting into
Sunday.

.REST OF TODAY...

Sky/weather.........Mostly cloudy (70-80 percent).
CWR.................0 percent.
Chance of thunder...0 percent.
Temperature.........24 at ignition...Max 37.
RH..................57 percent at ignition...Min 32 percent.
Eye level winds.....Winds winds 2 mph, using a 0.3 adjustment factor.
Wind (20 ft)........Winds winds 5 to 8 mph.
Mixing height.......900 ft AGL at ignition...otherwise max 3700 ft
                    AGL.
Transport winds.....West 10 to 17 mph decreasing to around 7 mph
                    late in the afternoon.
Smoke dispersal.....Poor /1480 m/s-m/ at ignition. Max...good /8170
                    m/s-m/.

TIME (CST)      9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM 6PM 7PM 8PM
Sky (%).........77  77  81  83  84  80  68  65  62  55  52  56
Weather cov.....
Weather type....
Tstm cov........
CWR.............0   0   0   0   0   0   0   0   0   0   0   0
Chc of thdr (%).0   0   0   0   0   0   0   0   0   0   0   0
Temp............24  28  32  35  36  37  37  37  35  33  30  29
RH..............57  46  39  35  33  32  34  35  40  45  51  53
20 FT wind dir..SW  W   W   W   W   W   W   W   W   W   NW  N
20 FT wind spd..7   7   7   7   8   8   8   6   5   4   4   6
20 FT wind gust.10  11  11  12  12  12  11  10  7   7   7   9
Eye lvl wnd dir.SW  W   W   W   W   W   W   W   W   W   NW  N
Eye lvl wnd spd.3   3   3   3   4   4   4   3   2   2   2   3
Eye lvl wnd gst.5   5   5   6   6   6   5   5   3   3   3   4
Mix hgt (kft)...0.9 2.0 2.8 3.5 3.6 3.7 3.6 3.1 1.0 0.4 0.4 0.5
Transp wind dir.W   W   W   W   W   W   W   W   W   NW  NW  NW
Transp wind spd.12  16  16  17  16  16  14  10  7   7   8   10
Vrate kt-ft/1K..9   29  40  52  50  51  44  28  6   3   3   4
Ventrate Cat....PR  PR  PR  FR  FR  FR  FR  PR  PR  PR  PR  PR

.TONIGHT...

Sky/weather.........Mostly cloudy (55-65 percent).
CWR.................0 percent.
Chance of thunder...0 percent.
Temperature.........Min 3.
RH..................Max 60 percent.
Eye level winds.....North winds 2 to 4 mph, using a 0.3 adjustment
                    factor.
Wind (20 ft)........North winds 5 to 14 mph.
Mixing height.......Min 400 ft AGL.
Transport winds.....Northwest 7 to 14 mph shifting to the north 17
                    to 23 mph in the late evening and overnight.
Smoke dispersal.....Fair (7510 m/s-m) early in the evening
                    decreasing to poor min (420 m/s-m) late in the
                    night.

.FRIDAY...

Sky/weather.........Mostly cloudy (75-85 percent).
CWR.................0 percent.
Chance of thunder...0 percent.
Temperature.........Max 7.
RH..................Min 28 percent.
Eye level winds.....North winds 2 to 4 mph with gusts up to 7 mph,
                    using a 0.3 adjustment factor.
Wind (20 ft)........North winds 8 to 12 mph with gusts up to 24 mph.
Mixing height.......Max 2900 ft AGL.
Transport winds.....North 16 to 24 mph.
Smoke dispersal.....Marginal (5880 m/s-m) early in the morning
                    increasing to good max (9100 m/s-m) in the
                    afternoon.

$$
Forecaster...Pfahler
Requested by...Assistant Superintendent
Type of request...PRESCRIBED
.TAG 2600886.0/LSX
.DELDT 01/22/26
.FormatterVersion 2.0.0