055
FNUS73 KLSX 101401
FWSLSX

Spot Forecast for Beaver Dam State Park...Illinois Department of Natural Resources
National Weather Service Saint Louis MO
901 AM CDT Tue Mar 10 2026

Forecast is based on ignition time of 1000 CDT on March 10.
If conditions become unrepresentative, contact the
National Weather Service.

.DISCUSSION...
Southerly winds will continue today. This will produce near
record warmth, and increasing moisture. As such, dewpoints will
not mix out much this afternoon with minimum relative humidity
values around 50 percent forecast. Mixing heights this morning
will start around 1000 ft as low level stratus and fog remains
near the burn site. This afternoon, even with full sun, mixing
heights will only top out around 3500 to 4200 ft as strong
southerly winds helps to increase an inversion around 850 mb.

Strong southerly winds combined with these mixing heights will
produce good to excellent ventilation rates. Most of the afternoon
today will likely be dry with showers and thunderstorms starting
early this afternoon, mainly across northeast Missouri into west
central Illinois. More widespread rain and thunderstorms are
expected overnight into Wednesday. Locally heavy rainfall is
possible with the storms overnight. Dry weather is expected
Thursday through Saturday. Temperatures will be cooler on Thursday,
but will warm up above normal again Friday into Saturday.


.REST OF TODAY...

Sky/weather.........Sunny (15-25 percent).
CWR.................5 percent.
Temperature.........70 at ignition...Max 82.
RH..................75 percent at ignition...Min 50 percent.
Eye level winds.....Winds south at 3 mph at ignition... otherwise
                    South winds around 5 mph with gusts to around 8 mph.
                    Adjustment factor of 0.3 used.
Wind (20 ft)........Winds south at 10 mph at ignition...otherwise
                    South winds 15 to 20 mph with gusts to around
                    25 mph.
Mixing height.......1000 ft AGL at ignition...otherwise max 4000 ft
                    AGL.
Transport winds.....Southwest 25 to 30 mph.
Smoke dispersal.....Marginal /4760 m/s-m/ at ignition.
                    Max...excellent /16140 m/s-m/.

TIME (CDT)      10 AM  NOON   2 PM   4 PM   6 PM   8 PM
Sky (%).........28     11     34     0      29     39
Weather cov.....
Weather type....NONE   NONE   NONE   NONE   NONE   NONE
Tstm cov........
CWR.............0      0      0      0      80     80
Temp............70     75     80     82     80     73
RH..............76     66     58     51     54     71
20 ft wind......S 11   S 13   S 16   S 17   S 16   S 15
20 ft wind gust.21     20     22     24     25     25
Eye level wind..S 5    S 6    S 7    S 8    S 7    S 7
Eye lvl wnd gst.10     9      10     11     12     12
Mix hgt (kft)...1.0    2.0    3.5    4.0    3.2    2.1
Transport wind..SW 20  SW 22  S 25   S 29   S 30   S 25
Vrate kt-ft/1K..30     58     81     102    83     47
Ventrate Cat....POOR   FAIR   GOOD   VYGD   GOOD   FAIR

.TONIGHT...

Sky/weather.........Partly cloudy (35-45 percent) then becoming
                    mostly cloudy (65-75 percent). Slight chance of
                    showers and thunderstorms in the evening, then
                    showers with thunderstorms likely overnight.
CWR.................85 percent.
Temperature.........Min 49.
RH..................Max 95 percent.
Eye level winds.....Southwest winds around 8 mph. Gusts up to 11 mph.
                    Adjustment factor of 0.3 used.
Wind (20 ft)........Southwest winds 15 to 20 mph. Gusts up to 35 mph.
                    Gusty and erratic winds expected near thunderstorms
                    in the late evening and overnight.
Mixing height.......Min 1500 ft AGL.
Transport winds.....Southwest 20 to 30 mph shifting to the west
                    around 15 mph early in the morning.
Smoke dispersal.....Good (13070 m/s-m) early in the evening
                    decreasing to marginal min (5470 m/s-m) late in
                    the night.

.WEDNESDAY...

Sky/weather.........Cloudy (85-95 percent) then becoming partly
                    sunny (65-75 percent). Showers with
                    thunderstorms likely in the morning, then
                    showers likely in the afternoon.
CWR.................100 percent.
Temperature.........Max 61.
RH..................Min 60 percent.
Eye level winds.....Southwest winds around 4 mph shifting to the
                    northwest 5 mph in the late morning and
                    afternoon. Gusts up to 10 mph. Adjustment factor
                    of 0.3 used.
Wind (20 ft)........Southwest winds around 12 mph shifting to the
                    northwest 16 to 18 mph in the late morning and
                    afternoon. Gusts up to 30 mph. Gusty and
                    erratic winds expected near thunderstorms early
                    in the morning.
Mixing height.......Max 4200 ft AGL.
Transport winds.....West 15 to 20 mph increasing to northwest 30 to
                    35 mph in the late morning and afternoon.
Smoke dispersal.....Fair (7340 m/s-m) early in the morning
                    increasing to excellent max (18350 m/s-m) in
                    the afternoon.

$$
Forecaster...Pfahler/ BAH
Requested by...Emma Launer
Type of request...PRESCRIBED
.TAG 2605272.0/LSX
.DELDT 03/10/26
.FormatterVersion 2.0.0