130
FNUS73 KLSX 251043
FWSLSX
SPOT FORECAST FOR FORBY UNIT...ST. LOUIS COUNTY PARKS FORESTRY
NATIONAL WEATHER SERVICE SAINT LOUIS MO
543 AM CDT WED MAR 25 2026
FORECAST IS BASED ON IGNITION TIME OF 1100 CDT ON MARCH 25.
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE
NATIONAL WEATHER SERVICE.
DISCUSSION
WELL ABOVE AVERAGE TEMPERATURES AND DRY CONDITIONS ARE EXPECTED
TODAY WITH SOME CLOUDS AND LIGHT SOUTHWESTERLY WINDS. FROM
IGNITION TIME INTO THE AFTERNOON, RH WILL GENERALLY BE BETWEEN
30 AND 45 PERCENT. MIXING HEIGHTS WILL ALSO BE RISING FROM AROUND
1500 FT AGL AT IGNITION TO BETWEEN 3000 AND 5000 FT AGL THIS
AFTERNOON, QUICKLY IMPROVING SMOKE DISPERSAL TO GOOD DESPITE THE
LIGHT WIND. A TEMPERATURE INVERSION WILL DEVELOP AROUND SUNSET,
OR 6 TO 7 PM THIS EVENING, ABRUPTLY DEGRADING SMOKE DISPERSAL.
REST OF TODAY
SKY/WEATHER.........MOSTLY SUNNY (30-40 PERCENT).
TEMPERATURE.........64 AT IGNITION...MAX 79.
RH..................45 PERCENT AT IGNITION...MIN 36 PERCENT.
EYE LEVEL WINDS.....WINDS SOUTHWEST AT 2 MPH. AN ADJUSTMENT FACTOR
OF 0.4 IS USED.
WIND (20 FT)........WINDS SOUTHWEST AT 4 TO 6 MPH.
MIXING HEIGHT.......1700 FT AGL AT IGNITION...OTHERWISE MAX 4600 FT
AGL.
TRANSPORT WINDS.....SOUTHWEST 12 TO 18 MPH.
SMOKE DISPERSAL.....POOR /2640 M/S-M/ AT IGNITION. MAX...GOOD
/11140 M/S-M/.
TIME (CDT) 11A 12P 1PM 2PM 3PM 4PM 5PM 6PM 7PM 8PM 9PM 10P
SKY (%).........26 29 33 37 41 44 45 44 40 34 27 22
WEATHER COV.....
WEATHER TYPE....
TSTM COV........
TEMP............64 70 73 76 78 79 79 79 76 73 71 70
RH..............45 42 40 37 38 36 38 39 46 49 55 57
20 FT WIND DIR..S S SW SW SW SW S S S S S S
20 FT WIND SPD..4 5 5 6 6 6 6 5 5 5 5 5
20 FT WIND GUST.11 12 13 14 14 15 14 13 12 13 14 15
EYE LVL WND DIR.S S SW SW SW SW S S S S S S
EYE LVL WND SPD.2 2 2 3 3 3 3 2 2 2 2 2
EYE LVL WND GST.5 6 6 6 6 7 6 6 6 6 6 7
MIX HGT (KFT)...1.7 2.4 3.4 4.0 4.6 4.6 4.4 1.2 0.4 0.4 0.5 0.6
TRANSP WIND DIR.SW SW SW SW SW SW SW S S S S S
TRANSP WIND SPD.12 12 14 16 16 17 18 15 13 14 14 16
VRATE KT-FT/1K..17 24 41 57 64 69 71 15 5 5 6 9
VENTRATE CAT....PR PR FR FR GD GD GD PR PR PR PR PR
FORECASTER...PFAHLER
REQUESTED BY...JASON PRATTE
TYPE OF REQUEST...PRESCRIBED
.TAG 2607739.0/LSX
.DELDT 03/25/26
.FORMATTERVERSION 2.0.0
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