193
FNUS73 KLSX 160809
FWSLSX

Spot Forecast for White River Trace Grassland RXB...Missouri Department of Conservation
National Weather Service Saint Louis MO
309 AM CDT Wed Apr 16 2025

Forecast is based on ignition time of 0800 CDT on April 16.
If conditions become unrepresentative, contact the
National Weather Service.

.DISCUSSION...
Light and variable winds this morning will become southerly by
mid morning, increasing in speed through mid afternoon. RH values
will reach their minimum around 30% during the early afternoon,
though surrounding areas are forecast to drop into the low to mid
20s. If the local area is a little warmer and/or a little drier
than currently expected, RH values could drop as low as 20%.

By 11 am the atmosphere will be mixing to 1200-2000 ft, and will
reach its maximum mixed height around 5,000 ft by 3-5 PM.

By 4 PM a 15-20% chance for showers and thunderstorms will move
into the area, though confidence in development is low at this
point.

.REST OF TODAY...

Sky/weather.........Mostly sunny (20-30 percent). Slight chance of
                    rain showers late in the afternoon.
Temperature.........43 at ignition...Max 72.
RH..................57 percent at ignition...Min 25 percent.
Wind (20 ft)........Winds south at 3 mph at ignition...otherwise
                    Light winds becoming south 5 to 9 mph in the
                    late morning and afternoon.
Eye level winds.....1-4 mph using an adjustment factor of 0.4.
Mixing height.......2100 ft AGL at ignition...otherwise max 4600 ft
                    AGL.
Transport winds.....South 8 to 17 mph increasing to around 20 mph
                    late in the afternoon.
Smoke dispersal.....Poor /420 m/s-m/ at ignition. Max...good /11990
                    m/s-m/.

TIME (CDT)      8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM 6PM 7PM
Sky (%).........2   2   6   6   22  35  33  41  50  46  54  54
Weather cov.....                            SCH SCH SCH SCH SCH
Weather type....                            RW  RW  RW  RW  RW
Tstm cov........                                            SCH
Temp............43  53  61  66  68  71  72  72  72  72  70  66
RH..............57  46  35  30  27  25  26  25  26  27  30  38
20 FT wind dir..S   S   S   S   S   S   S   S   S   S   S   S
20 FT wind spd..3   4   5   6   8   9   9   9   9   9   9   9
20 FT wind gust.9   9   8   11  12  13  14  15  14  16  17  20
Eye lvl wnd dir.S   S   S   S   S   S   S   S   S   S   S   S
Eye lvl wnd spd.1   2   2   3   4   4   4   4   4   4   4   4
Eye lvl wnd gst.4   4   4   5   6   6   6   7   6   7   8   9
Mix hgt (kft)...0.4 0.7 2.1 2.9 3.6 4.1 4.5 4.2 4.6 4.5 1.9 0.7
Transp wind dir.SW  S   S   S   S   S   S   S   S   S   S   S
Transp wind spd.8   8   9   12  15  15  16  16  17  20  17  15
Vrate kt-ft/1K..3   5   17  29  47  54  63  59  69  76  29  9
Ventrate Cat....PR  PR  PR  PR  FR  FR  GD  FR  GD  GD  PR  PR

.TONIGHT...

Sky/weather.........Mostly cloudy (60-70 percent). Slight chance of
                    showers and thunderstorms in the evening, then
                    chance of showers and thunderstorms overnight.
Temperature.........Min 52.
RH..................Max 77 percent.
Wind (20 ft)........South winds 9 to 10 mph with gusts to around 24
                    mph. Gusty and erratic winds expected near
                    thunderstorms.
Eye level winds.....4-10 mph, using an adjustment factor of 0.4.
Mixing height.......Min 500 ft AGL.
Transport winds.....South 15 to 20 mph.
Smoke dispersal.....Poor (1180 m/s-m).

.THURSDAY...

Sky/weather.........Partly sunny (50-60 percent) then becoming
                    sunny (15-25 percent). Rain showers likely and
                    chance of thunderstorms in the morning.
Temperature.........Max 78.
RH..................Min 47 percent.
Wind (20 ft)........South winds 10 to 18 mph. Gusts up to 33 mph
                    increasing to 38 mph in the afternoon. Gusty
                    and erratic winds expected near thunderstorms
                    early in the morning. Gusty and erratic winds
                    expected near thunderstorms late in the
                    morning.
Eye level winds.....4-7 mph, gusting 13-15 mph, using an adjustment
factor of 0.4.
Mixing height.......Max 4100 ft AGL.
Transport winds.....South 20 to 26 mph increasing to 31 to 39 mph
                    late in the morning.
Smoke dispersal.....Poor (1480 m/s-m) early in the morning
                    increasing to good max (12820 m/s-m) in the
                    afternoon increasing to good (14060 m/s-m)
                    early in the morning increasing to excellent
                    max (20440 m/s-m) in the afternoon in the
                    afternoon.

$$
Forecaster...Delia
Requested by...Matthew Peter
Type of request...PRESCRIBED
.TAG 2510569.0/LSX
.DELDT 04/16/25
.FormatterVersion 2.0.0