058 
FNUS73 KLSX 201332
FWSLSX

Spot Forecast for Beaver Dam...IDNR
National Weather Service Saint Louis MO
832 AM CDT Thu Mar 20 2025

Forecast is based on ignition time of 1000 CDT on March 20. 
If conditions become unrepresentative, contact the
National Weather Service.

.DISCUSSION...
Clouds will clear before ignition time, with a sunny, seasonably cool
day today. At ignition, RH will be around 55 to 60 percent but strong 
northwesterly winds (sustained 18 to 22 mph, gusting 25 to 30 mph) 
seasonably high mixing heights around 3000 ft AGL will keep ventilation 
rates from being poor. Conditions will further improvement through late 
morning into afternoon with RH falling to between 35 and 45 percent and 
ventilation rates becoming more favorable as mixing heights rise to 
around 5000 ft AGL and low-level instability increases, while 
northwesterly winds start to gradually slacken and gusts become less 
common.

.REST OF TODAY...

Sky/weather.........Sunny (10-20 percent). 
Chance of pcpn......0 percent. 
Temperature.........36 at ignition...Max 46. 
RH..................59 percent at ignition...Min 35 percent. 
Wind (20 ft)........Winds northwest at 20 mph with gusts to around 
                    25 mph at ignition...becoming 13 to 19 mph in 
                    the afternoon.
Eye level winds.....Winds northwest at 6 mph with gusts to around 
                    8 mph at ignition...becoming 4 to 6 mph in 
                    the afternoon, using a 0.3 adjustment factor.
Mixing height.......3100 ft AGL at ignition...otherwise max 5100 ft 
                    AGL. 
Transport winds.....Northwest 23 to 28 mph. 
Smoke dispersal.....Good /11670 m/s-m/ at ignition. Max...excellent 
                    /18590 m/s-m/. 

TIME (CDT)      10 AM  NOON   2 PM   4 PM   6 PM   8 PM   
Sky (%).........31     11     4      1      1      2      
Weather cov.....                                          
Weather type....NONE   NONE   NONE   NONE   NONE   NONE   
Tstm cov........                                          
CWR.............0      0      0      0      0      0      
Temp............36     40     43     46     45     39     
RH..............59     48     41     35     38     50     
20 ft wind......NW 19  NW 18  NW 17  NW 15  NW 11  W 6    
20 ft wind gust.25     25     24     22     16     10     
Eye level wind..NW 9   NW 8   NW 8   NW 7   NW 5   W 3    
Eye lvl wnd gst.12     12     11     10     7      5      
Mix hgt (kft)...3.1    4.1    5.1    5.1    4.7    0.6    
Transport wind..NW 28  NW 26  NW 26  NW 25  NW 22  NW 10  
Vrate kt-ft/1K..74     95     118    114    89     5      
Ventrate Cat....GOOD   GOOD   VYGD   VYGD   GOOD   POOR   

.TONIGHT...

Sky/weather.........Mostly clear (5-15 percent). 
Chance of pcpn......0 percent. 
Temperature.........Min 31. 
RH..................Max 75 percent. 
Wind (20 ft)........Northwest winds 6 to 11 mph early in the 
                    evening becoming light, then becoming south 5 
                    to 7 mph overnight. 
Eye level winds.....Northwest winds 2 to 3 mph early in the 
                    evening becoming light, then becoming south 2 
                    mph overnight, using a 0.3 adjustment factor.
Mixing height.......Min 300 ft AGL. 
Transport winds.....Northwest 15 to 22 mph decreasing to 7 to 10 
                    mph early in the evening, then shifting to the 
                    southwest 7 to 9 mph late in the evening 
                    shifting to the south 10 to 15 mph after 3 am. 
Smoke dispersal.....Good (14030 m/s-m) early in the evening 
                    decreasing to poor min (310 m/s-m) late in the 
                    night. 

.FRIDAY...

Sky/weather.........Mostly sunny (35-45 percent) then becoming 
                    mostly cloudy (70-80 percent). 
Chance of pcpn......0 percent. 
Temperature.........Max 63. 
RH..................Min 30 percent. 
Wind (20 ft)........South winds 8 to 17 mph with gusts to around 31 
                    mph shifting to the southwest 16 to 18 mph with 
                    gusts to around 36 mph in the afternoon. 
Eye level winds.....South winds 2 to 5 mph with gusts to around 9 
                    mph shifting to the southwest 5  mph with 
                    gusts to around 11 mph in the afternoon, using a 
                    0.3 adjustment factor.
Mixing height.......Max 5500 ft AGL. 
Transport winds.....South 16 to 25 mph increasing to southwest 29 
                    to 37 mph late in the morning. 
Smoke dispersal.....Poor (970 m/s-m) early in the morning 
                    increasing to excellent max (15460 m/s-m) in 
                    the afternoon increasing to excellent (17860 
                    m/s-m) late in the afternoon. 

$$
Forecaster...Pfahler
Requested by...RG
Type of request...PRESCRIBED
.TAG 2507222.0/LSX
.DELDT 03/20/25
.FormatterVersion 2.0.0