040  
FNUS73 KLSX 221552  
FWSLSX  
 
SPOT FORECAST FOR 107 PRAIRIE - MTSP...DEPARTMENT OF NATURAL RESOURCES  
NATIONAL WEATHER SERVICE SAINT LOUIS MO  
952 AM CST THU JAN 22 2026  
 
FORECAST IS BASED ON IGNITION TIME OF 0900 CST ON JANUARY 22.  
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE  
NATIONAL WEATHER SERVICE.  
   
DISCUSSION
 
 
DRY CONDITIONS AND NEAR AVERAGE TEMPERATURES ARE EXPECTED TODAY. AROUND  
IGNITION TIME, WINDS WILL BECOME WESTERLY WITH RH ALSO FALLING  
BELOW 60 PERCENT, REACHING THE 30S PERCENT THIS AFTERNOON. MIXING  
HEIGHTS WILL BE RISING FROM 750 FT AGL AT IGNITION TIME TO BETWEEN  
3250 TO 3750 FT AGL THIS AFTERNOON, HELPING SMOKE DISPERSAL IMPROVE  
FROM POOR THIS MORNING TO GOOD THIS AFTERNOON.  
 
TONIGHT A COLD FRONT WILL PASS THROUGH THE REGION, VEERING WINDS TO  
NORTHERLY AND STRENGTHENING THEM. STEADY NORTHERLY WINDS WILL CONTINUE  
ON FRIDAY SUSTAINED 12 TO 16 MPH AND USHERING BITTERLY COLD AIR INTO  
THE AREA. WIDESPREAD ACCUMULATING SNOW WILL ARRIVE SATURDAY, LASTING INTO  
SUNDAY.  
   
REST OF TODAY
 
 
SKY/WEATHER.........MOSTLY CLOUDY (70-80 PERCENT).  
CWR.................0 PERCENT.  
CHANCE OF THUNDER...0 PERCENT.  
TEMPERATURE.........24 AT IGNITION...MAX 37.  
RH..................57 PERCENT AT IGNITION...MIN 32 PERCENT.  
EYE LEVEL WINDS.....WINDS WINDS 2 MPH, USING A 0.3 ADJUSTMENT FACTOR.  
WIND (20 FT)........WINDS WINDS 5 TO 8 MPH.  
MIXING HEIGHT.......900 FT AGL AT IGNITION...OTHERWISE MAX 3700 FT  
AGL.  
TRANSPORT WINDS.....WEST 10 TO 17 MPH DECREASING TO AROUND 7 MPH  
LATE IN THE AFTERNOON.  
SMOKE DISPERSAL.....POOR /1480 M/S-M/ AT IGNITION. MAX...GOOD /8170  
M/S-M/.  
 
TIME (CST) 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM 6PM 7PM 8PM  
SKY (%).........77 77 81 83 84 80 68 65 62 55 52 56  
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 0  
TEMP............24 28 32 35 36 37 37 37 35 33 30 29  
RH..............57 46 39 35 33 32 34 35 40 45 51 53  
20 FT WIND DIR..SW W W W W W W W W W NW N  
20 FT WIND SPD..7 7 7 7 8 8 8 6 5 4 4 6  
20 FT WIND GUST.10 11 11 12 12 12 11 10 7 7 7 9  
EYE LVL WND DIR.SW W W W W W W W W W NW N  
EYE LVL WND SPD.3 3 3 3 4 4 4 3 2 2 2 3  
EYE LVL WND GST.5 5 5 6 6 6 5 5 3 3 3 4  
MIX HGT (KFT)...0.9 2.0 2.8 3.5 3.6 3.7 3.6 3.1 1.0 0.4 0.4 0.5  
TRANSP WIND DIR.W W W W W W W W W NW NW NW  
TRANSP WIND SPD.12 16 16 17 16 16 14 10 7 7 8 10  
VRATE KT-FT/1K..9 29 40 52 50 51 44 28 6 3 3 4  
VENTRATE CAT....PR PR PR FR FR FR FR PR PR PR PR PR  
   
TONIGHT
 
 
SKY/WEATHER.........MOSTLY CLOUDY (55-65 PERCENT).  
CWR.................0 PERCENT.  
CHANCE OF THUNDER...0 PERCENT.  
TEMPERATURE.........MIN 3.  
RH..................MAX 60 PERCENT.  
EYE LEVEL WINDS.....NORTH WINDS 2 TO 4 MPH, USING A 0.3 ADJUSTMENT  
FACTOR.  
WIND (20 FT)........NORTH WINDS 5 TO 14 MPH.  
MIXING HEIGHT.......MIN 400 FT AGL.  
TRANSPORT WINDS.....NORTHWEST 7 TO 14 MPH SHIFTING TO THE NORTH 17  
TO 23 MPH IN THE LATE EVENING AND OVERNIGHT.  
SMOKE DISPERSAL.....FAIR (7510 M/S-M) EARLY IN THE EVENING  
DECREASING TO POOR MIN (420 M/S-M) LATE IN THE  
NIGHT.  
   
FRIDAY
 
 
SKY/WEATHER.........MOSTLY CLOUDY (75-85 PERCENT).  
CWR.................0 PERCENT.  
CHANCE OF THUNDER...0 PERCENT.  
TEMPERATURE.........MAX 7.  
RH..................MIN 28 PERCENT.  
EYE LEVEL WINDS.....NORTH WINDS 2 TO 4 MPH WITH GUSTS UP TO 7 MPH,  
USING A 0.3 ADJUSTMENT FACTOR.  
WIND (20 FT)........NORTH WINDS 8 TO 12 MPH WITH GUSTS UP TO 24 MPH.  
MIXING HEIGHT.......MAX 2900 FT AGL.  
TRANSPORT WINDS.....NORTH 16 TO 24 MPH.  
SMOKE DISPERSAL.....MARGINAL (5880 M/S-M) EARLY IN THE MORNING  
INCREASING TO GOOD MAX (9100 M/S-M) IN THE  
AFTERNOON.  
 

 
FORECASTER...PFAHLER  
REQUESTED BY...ASSISTANT SUPERINTENDENT  
TYPE OF REQUEST...PRESCRIBED  
.TAG 2600886.0/LSX  
.DELDT 01/22/26  
.FORMATTERVERSION 2.0.0  
 
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