306
FNUS73 KLSX 221913
FWSLSX
SPOT FORECAST FOR BRUSH FIRE...WASHINGTON COUNTY IL EMA
NATIONAL WEATHER SERVICE SAINT LOUIS MO
213 PM CDT WED OCT 22 2025
FORECAST IS BASED ON FORECAST START TIME OF 1400 CDT ON OCTOBER 22.
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE
NATIONAL WEATHER SERVICE.
DISCUSSION
MOSTLY SUNNY CONDITIONS ARE EXPECTED TODAY WITH HIGHS IN THE LOW
TO MID-60S. SUSTAINED NORTHWEST WINDS OF 10-15 MPH WILL OCCASIONALLY
GUST TO AS HIGH AS 25 MPH AT TIMES. RELATIVE HUMIDITY WILL GENERALLY
RANGE FROM 30-35% WITH MINIMUM RH VALUES IN THE UPPER 20S. SUNSHINE
AND DEEPER MIXING, WHICH IS AIDING IN HIGHER WINDS, WILL ALSO KEEP
MIXING HEIGHTS BETWEEN 4,500-5,000 THROUGH LATE THIS AFTERNOON.
FORTUNATELY, STRONGER WINDS WILL MAKE FOR GOOD VENTILATIONS RATES
THROUGH LATE EVENING. AS WE APPROACH SUNSET, TEMPERATURES WILL COOL
EFFICIENTLY, ALONG WITH THE DEVELOPMENT OF THE DIURNAL INVERSION.
INVERSION WILL LIMIT MIXING HEIGHTS TO AROUND 400 FEET OR LESS, ALONG
WITH POOR VENTILATION OF SUBSIDING WINDS.
REST OF TODAY
SKY/WEATHER.........SUNNY (0-5 PERCENT).
CWR.................0 PERCENT.
CHANCE OF THUNDER...0 PERCENT.
TEMPERATURE.........62 AT FORECAST START...MAX 64.
RH..................28 PERCENT AT FORECAST START...MIN 28 PERCENT.
EYE LEVEL WINDS.....WEST WINDS AT 4-5 MPH, OCCASIONALLY GUSTING NEAR
20 MPH. MULTIPLICATION FACTOR OF 0.4 USED.
WIND (20 FT)........WINDS WEST AT 11 MPH AT FORECAST
START...OTHERWISE WEST WINDS 10 TO 12 MPH.
GUSTS UP TO 23 MPH LATE IN THE AFTERNOON.
MIXING HEIGHT.......4100 FT AGL AT FORECAST START...OTHERWISE MAX
4700 FT AGL.
TRANSPORT WINDS.....WEST 20 TO 25 MPH.
SMOKE DISPERSAL.....GOOD /13610 M/S-M/ AT FORECAST START.
MAX...EXCELLENT /16250 M/S-M/.
TIME (CDT) 2 PM 4 PM 6 PM 8 PM 10 PM MIDNGT
SKY (%).........2 1 2 2 4 4
WEATHER COV.....
WEATHER TYPE....NONE NONE NONE NONE NONE NONE
TSTM COV........
CWR.............0 0 0 0 0 0
CHC OF THDR (%).0 0 0 0 0 0
TEMP............62 63 59 52 48 46
RH..............28 30 39 54 65 71
20 FT WIND......W 11 W 12 W 7 W 4 W 4 W 3
20 FT WIND GUST.18 19 13 10 8 7
EYE LEVEL WIND..W 5 W 6 W 3 W 2 W 2 W 1
EYE LVL WND GST.8 9 6 5 4 3
MIX HGT (KFT)...4.1 4.7 0.6 0.4 0.4 0.4
TRANSPORT WIND..W 24 W 24 W 12 W 10 NW 9 NW 9
VRATE KT-FT/1K..87 98 6 3 3 3
VENTRATE CAT....GOOD GOOD POOR POOR POOR POOR
TONIGHT
SKY/WEATHER.........CLEAR (0-10 PERCENT).
CWR.................0 PERCENT.
CHANCE OF THUNDER...0 PERCENT.
TEMPERATURE.........MIN 38.
RH..................MAX 85 PERCENT.
EYE LEVEL WINDS.....WEST WINDS OF 3-4 MPH, BECOMING LIGHT AND VARIABLE.
MULTIPLICATION FACTOR OF 0.4 USED.
WIND (20 FT)........WEST WINDS AROUND 7 MPH DECREASING TO AROUND 5
MPH EARLY IN THE EVENING, THEN BECOMING LIGHT
EARLY IN THE EVENING.
MIXING HEIGHT.......MIN 400 FT AGL.
TRANSPORT WINDS.....NORTHWEST 9 TO 12 MPH SHIFTING TO THE NORTH 8
TO 9 MPH OVERNIGHT.
SMOKE DISPERSAL.....POOR (410 M/S-M).
FORECASTER...MAPLES
REQUESTED BY...DARRAH SABO
TYPE OF REQUEST...WILDFIRE
.TAG 2524239.0/LSX
.DELDT 10/22/25
.FORMATTERVERSION 2.0.0
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