540  
FNUS73 KLOT 302150  
FWSLOT  
 
SPOT FORECAST FOR CASTLE ROCK...IDNR  
NATIONAL WEATHER SERVICE CHICAGO IL  
450 PM CDT THU OCT 30 2025  
 
FORECAST IS BASED ON IGNITION TIME OF 1700 CDT ON OCTOBER 30.  
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER  
SERVICE.  
 
PLEASE CONTACT OUR OFFICE AT (815) 834-0666 IF YOU HAVE QUESTIONS  
OR CONCERNS WITH THIS FORECAST.  
   
DISCUSSION
 
 
AS THE SUN SETS, TEMPERATURES WILL FALL AND RELATIVE HUMIDITY  
VALUES WILL RISE. WINDS WILL REMAIN RELATIVELY LIGHT AND OUT OF  
THE WEST NORTHWEST THIS EVENING.  
 
TOMORROW LOOKS SIMILAR TO TODAY WITH GENERALLY WESTERLY WINDS  
PEAKING AT 10 TO 15 MPH AND PARTLY CLOUDY SKIES. RELATIVE HUMIDITY  
VALUES WILL REMAIN SOMEWHAT ELEVATED AND GENERALLY ABOVE 50  
PERCENT. A STRAY SHOWER OR TWO CANNOT BE RULED OUT DURING THE  
AFTERNOON HOURS.  
   
TONIGHT
 
 
SKY/WEATHER.........PARTLY CLOUDY.  
TEMPERATURE.........MIN 36.  
RH..................MAX 93 PERCENT.  
WIND (20 FT)........NORTHWEST WINDS 6 TO 7 MPH.  
CHANCE OF PCPN......0 PERCENT.  
TRANSPORT WINDS.....NORTHWEST 12 TO 14 MPH.  
MIXING HEIGHT.......400 FT AGL.  
SMOKE DISPERSAL.....POOR (4500 KNOT-FT).  
 
TIME (CDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM  
SKY (%).........64 69 73 78 87 87 87 84 73 63 59 50  
WEATHER COV.....  
WEATHER TYPE....  
TEMP............52 48 46 45 44 43 43 43 42 41 39 39  
RH..............57 67 73 77 79 79 78 78 79 84 90 91  
20 FT WIND DIR..290 290 290 290 290 310 310 310 310 300 300 300  
20 FT WIND SPD..8 7 7 7 8 8 8 8 7 7 7 7  
20 FT WIND GUST.13 13 13 13 13 15 14 14 14 13 13 13  
MIX HGT (KFT)...0.8 0.7 0.4 0.4 0.5 0.5 0.7 0.7 0.6 0.5 0.5 0.5  
TRANSP WIND DIR.290 290 290 290 290 310 310 310 310 300 300 300  
TRANSP WIND SPD.12 13 12 12 13 14 14 14 13 12 12 12  
CHC OF PCPN (%).0 0 0 0 0 0 0 0 0 0 0 0  
VRATE KT-FT/1K..8 8 5 5 5 6 9 9 7 5 5 5  
   
FRIDAY
 
 
SKY/WEATHER.........PARTLY CLOUDY WITH A SLIGHT CHANCE OF A RAIN  
SHOWER IN THE AFTERNOON.  
TEMPERATURE.........MAX 53.  
RH..................MIN 55 PERCENT.  
WIND (20 FT)........WEST WINDS 5 TO 10 MPH.  
CHANCE OF PCPN......20 PERCENT IN THE AFTERNOON.  
TRANSPORT WINDS.....WEST 10 TO 15 MPH INCREASING TO 16 TO 17 MPH IN  
THE AFTERNOON.  
MIXING HEIGHT.......4500 FT AGL.  
SMOKE DISPERSAL.....POOR (6100 KNOT-FT) EARLY IN THE MORNING  
INCREASING TO EXCELLENT (62700 KNOT-FT) IN THE  
AFTERNOON.  
 
TIME (CDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........41 38 35 34 34 33 35 39 44 45 46 50  
WEATHER COV..... SCH SCH  
WEATHER TYPE.... RW RW  
TEMP............38 37 37 39 43 46 49 51 52 52 51 50  
RH..............91 93 93 91 80 73 64 59 56 55 55 57  
20 FT WIND DIR..290 290 290 280 290 280 280 280 280 290 290 290  
20 FT WIND SPD..7 7 6 7 8 9 10 10 12 12 10 9  
20 FT WIND GUST.12 13 13 13 15 16 16 16 15 16 16 15  
MIX HGT (KFT)...0.6 0.6 0.8 0.9 1.4 2.0 3.0 4.1 4.1 4.1 4.5 2.6  
TRANSP WIND DIR.290 290 290 280 290 280 280 280 280 290 290 290  
TRANSP WIND SPD.13 12 10 12 13 14 15 17 16 16 16 16  
CHC OF PCPN (%).0 0 0 0 10 10 10 10 10 10 20 20  
VRATE KT-FT/1K..7 6 7 9 15 25 39 62 58 58 63 36  
 

 
FORECASTER...BORCHARDT  
REQUESTED BY...JEFF HORN  
TYPE OF REQUEST...PRESCRIBED  
.TAG 2524796.0/LOT  
.DELDT 10/30/25  
.FORMATTERVERSION 2.0.0  
 
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