114
FNUS73 KLSX 250941
FWSLSX
SPOT FORECAST FOR HERMANS HILLTOP BURN UNIT...DNR
NATIONAL WEATHER SERVICE SAINT LOUIS MO
441 AM CDT WED MAR 25 2026
FORECAST IS BASED ON IGNITION TIME OF 1000 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
1250 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).
CWR.................1 PERCENT.
CHANCE OF THUNDER...3 PERCENT.
TEMPERATURE.........47 AT IGNITION...MAX 79.
RH..................56 PERCENT AT IGNITION...MIN 35 PERCENT.
EYE LEVEL WINDS.....SOUTHWEST WINDS 2 MPH. AN ADJUSTMENT FACTOR OF
0.3 IS USED.
WIND (20 FT)........SOUTHWEST WINDS 5 TO 6 MPH.
MIXING HEIGHT.......400 FT AGL AT IGNITION...OTHERWISE MAX 4700 FT
AGL.
TRANSPORT WINDS.....SOUTHWEST 9 TO 18 MPH.
SMOKE DISPERSAL.....POOR /500 M/S-M/ AT IGNITION. MAX...GOOD /11160
M/S-M/.
TIME (CDT) 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM 6PM 7PM
SKY (%).........35 29 26 26 30 34 38 40 42 42 41 37
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 10
TEMP............47 53 60 66 70 74 76 79 79 79 79 76
RH..............56 52 44 42 44 38 37 35 36 38 39 46
20 FT WIND DIR..S S S S S SW SW SW SW SW S S
20 FT WIND SPD..2 2 3 4 4 5 5 5 6 5 5 5
20 FT WIND GUST.8 9 10 12 12 13 14 14 15 14 14 13
EYE LVL WND DIR.S S S S S SW SW SW SW SW S S
EYE LVL WND SPD.1 1 1 2 2 2 2 2 3 2 2 2
EYE LVL WND GST.4 4 5 6 6 6 6 6 7 6 6 6
MIX HGT (KFT)...0.4 0.6 1.2 1.9 2.7 3.6 4.3 4.6 4.7 4.4 1.6 0.5
TRANSP WIND DIR.S S SW SW SW SW SW SW SW SW S S
TRANSP WIND SPD.9 9 13 12 12 14 16 16 17 18 16 14
VRATE KT-FT/1K..3 5 13 19 27 44 60 65 71 71 22 6
VENTRATE CAT....PR PR PR PR PR FR FR GD GD GD PR PR
TONIGHT
SKY/WEATHER.........MOSTLY CLEAR (15-25 PERCENT).
CWR.................3 PERCENT.
CHANCE OF THUNDER...5 PERCENT.
TEMPERATURE.........MIN 64.
RH..................MAX 75 PERCENT.
EYE LEVEL WINDS.....SOUTHWEST WINDS 2 MPH. GUSTS UP TO 6 MPH
OVERNIGHT. AN ADJUSTMENT FACTOR OF 0.3 IS
USED.
WIND (20 FT)........SOUTHWEST WINDS 5 TO 6 MPH. GUSTS UP TO 21 MPH
OVERNIGHT.
MIXING HEIGHT.......MIN 400 FT AGL.
TRANSPORT WINDS.....SOUTHWEST 14 TO 17 MPH SHIFTING TO THE WEST
AROUND 17 MPH EARLY IN THE MORNING.
SMOKE DISPERSAL.....POOR (850 M/S-M).
THURSDAY
SKY/WEATHER.........SUNNY (15-25 PERCENT).
CWR.................2 PERCENT.
CHANCE OF THUNDER...7 PERCENT.
TEMPERATURE.........MAX 91.
RH..................MIN 35 PERCENT.
EYE LEVEL WINDS.....SOUTHWEST WINDS 2 MPH WITH GUSTS TO AROUND 6 MPH.
AN ADJUSTMENT FACTOR OF 0.3 IS USED.
WIND (20 FT)........SOUTHWEST WINDS 5 TO 8 MPH WITH GUSTS TO AROUND
21 MPH.
MIXING HEIGHT.......MAX 5200 FT AGL.
TRANSPORT WINDS.....SOUTHWEST 16 TO 22 MPH INCREASING TO 24 TO 31
MPH IN THE LATE MORNING AND AFTERNOON.
SMOKE DISPERSAL.....POOR (1790 M/S-M) EARLY IN THE MORNING
INCREASING TO EXCELLENT MAX (15370 M/S-M) IN
THE AFTERNOON INCREASING TO GOOD (14490 M/S-M)
EARLY IN THE MORNING INCREASING TO EXCELLENT
MAX (22150 M/S-M) IN THE AFTERNOON LATE IN THE
AFTERNOON.
FORECASTER...PFAHLER
REQUESTED BY...ERIK OTTO
TYPE OF REQUEST...PRESCRIBED
.TAG 2607665.0/LSX
.DELDT 03/25/26
.FORMATTERVERSION 2.0.0
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