FNUS73 KLSX 121335

FWSLSX



Spot Forecast for BRS 2025-2 burn...Columbia fire

National Weather Service Saint Louis MO

735 AM CST Fri Dec 12 2025



Forecast is based on ignition time of 0800 CST on December 12. 

If conditions become unrepresentative, contact the

National Weather Service.



.DISCUSSION...

Cloudy and cool conditions are expected throughout the day, with

perhaps a few very brief cloud breaks in the mid to late 

afternoon. Humidity will remain high, and winds will be generally 

northerly and light. You may also see a very slight and gradual 

shift from northerly to northwesterly overall, but with such light

speeds, the direction is likely to fluctuate periodically 

throughout the day. Very low mixing heights are also expected, and

when combined with the light wind speeds, ventilation will be 

poor for most of the day, with some very slight improvement in the

mid to late afternoon. Nearly calm winds, cold temperatures, and 

high humidity are expected overnight.



.REST OF TODAY...



Sky/weather.........Cloudy (85-95 percent). 

CWR.................0 percent. 

Chance of thunder...0 percent. 

Temperature.........30 at ignition...Max 36. 

RH..................88 percent at ignition...Min 69 percent. 

Eye level winds.....Winds north 2 to 4 mph, shifting slightly 

                    to the northwest in the afternoon.

Wind (20 ft)........Winds north 4 to 8 mph, shifting slightly 

                    to the northwest in the afternoon.  

Mixing height.......1200 ft AGL at ignition...otherwise max 2200 ft 

                    AGL. 

Transport winds.....North 8 to 12 mph. 

Smoke dispersal.....Poor /1900 m/s-m/ at ignition. Max...poor /2780 

                    m/s-m/. 



TIME (CST)      8 AM         NOON         4 PM         

Sky (%).........98           100          83           

Weather cov.....                                       

Weather type....NONE         NONE         NONE         

Tstm cov........                                       

CWR.............0            0            0            

Chc of thdr (%).0            0            0            

Temp............30           34           36           

RH..............88           78           69           

20 FT wind......N 6G12       N 6G11       NW 5G10      

Eye level wind..N 3G6        N 3G5        NW 2G5       

Mix hgt (kft)...1.2          2.0          2.0          

Transport wind..N 12         N 10         NW 9         

Vrate kt-ft/1K..12           18           16           

Ventrate Cat....POOR         POOR         POOR         



.TONIGHT...



Sky/weather.........Mostly cloudy (75-85 percent). 

CWR.................0 percent. 

Chance of thunder...0 percent. 

Temperature.........Min 22. 

RH..................Max 92 percent. 

Eye level winds.....Nearly calm.

Wind (20 ft)........3 mph or less, variable direction. 

Mixing height.......Min 500 ft AGL. 

Transport winds.....Northwest 5 to 9 mph shifting to the northeast 

                    around 6 mph early in the morning. 

Smoke dispersal.....Poor (440 m/s-m). 



$$

Forecaster...19

Requested by...Daniel Sarkar

Type of request...PRESCRIBED

.TAG 2527553.0/LSX

.DELDT 12/12/25

.FormatterVersion 2.0.0