195  
FNUS75 KBOU 152225  
FWSBOU  
 
SPOT FORECAST FOR CO WRF PILES BLUE RIVER WEST...USFS  
NATIONAL WEATHER SERVICE DENVER/BOULDER CO  
325 PM MST MON DEC 15 2025  
 
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER  
SERVICE.  
   
DISCUSSION  
TUESDAY WILL BE MILD AND DRY WITH RELATIVE HUMIDITY  
DROPPING TO AROUND 35-40%. WITH WEST WINDS GUSTING UP TO 25 MPH  
AND MODERATELY HIGH MIXING HEIGHTS, FAIR SMOKE DISPERSAL WILL  
DEVELOP FROM THE LATE MORNING THROUGH THE LATE AFTERNOON.  
 
A STRONG LOW PRESSURE SYSTEM WILL APPROACH COLORADO ON WEDNESDAY  
AND WILL MOVE THROUGH THE AREA ON WEDNESDAY NIGHT. THIS SYSTEM  
WILL BRING STRONG WINDS THAT COULD GUST UP TO 40 MPH WEDNESDAY  
AFTERNOON AND GUSTS COULD REACH OVER 60 MPH WEDNESDAY NIGHT. SMOKE  
DISPERSAL WILL BE VERY GOOD ON WEDNESDAY AS THE STORM APPROACHES.  
THIS SYSTEM WILL ALSO BRING SNOW BEGINNING WEDNESDAY AFTERNOON  
LASTING THROUGH THURSDAY MORNING. 2-4" OF SNOW IS EXPECTED.  
   
TUESDAY  
 
SKY/WEATHER.........PARTLY CLOUDY (25-35 PERCENT).  
CWR.................1 PERCENT.  
CHANCE OF PCPN......0 PERCENT.  
MAX TEMPERATURE.....AROUND 43.  
MIN HUMIDITY........38 PERCENT.  
WIND (20 FT)........NORTHWEST WINDS 9 TO 14 MPH. GUSTS UP TO 21 MPH  
EARLY IN THE AFTERNOON THEN 20 MPH LATE IN THE  
AFTERNOON.  
MIXING HEIGHT.......2500 FT AGL.  
TRANSPORT WINDS.....NORTHWEST 14 TO 23 MPH UNTIL 1700, THEN AROUND  
12 MPH.  
SMOKE DISPERSAL.....POOR UNTIL 1100, THEN FAIR UNTIL 1500, THEN  
POOR.  
 
TIME (MST) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........32 24 21 28 16 11 16 22 24 24 22 9  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0 0 0 0  
CHC OF PCPN (%).0 0 0 0 0 0 0 0 0 0 0 0  
TEMP............24 24 26 33 38 42 42 43 42 40 37 31  
RH..............44 48 51 48 45 45 46 47 48 53 56 68  
20 FT WIND DIR..NW NW NW NW NW NW NW NW NW NW NW NW  
20 FT WIND SPD..10 10 10 10 10 12 12 13 13 12 10 9  
20 FT WIND GUST.16 16 16 16 16 18 18 21 21 18 16 20  
MIX HGT (KFT)...1.5 1.5 1.3 1.6 2.0 2.4 2.6 2.8 2.7 2.2 1.5 1.4  
TRANSP WIND DIR.W NW NW NW NW NW NW NW NW NW NW NW  
TRANSP WIND SPD.16 15 16 18 18 20 21 23 21 20 14 12  
VRATE KT-FT/1K..21 19 19 26 32 40 46 56 48 38 18 14  
SMOKEDISPERSION.P P P P P F F F F P P P  
   
TUESDAY NIGHT  
 
SKY/WEATHER.........MOSTLY CLEAR (10-20 PERCENT).  
CWR.................1 PERCENT.  
CHANCE OF PCPN......0 PERCENT.  
MIN TEMPERATURE.....AROUND 18.  
MAX HUMIDITY........89 PERCENT.  
WIND (20 FT)........NORTHWEST WINDS 5 TO 13 MPH UNTIL 2000. WEST 6  
TO 11 MPH WITH GUSTS TO AROUND 22 MPH AFTER  
2300.  
MIXING HEIGHT.......1300 FT AGL.  
TRANSPORT WINDS.....NORTHWEST 9 TO 14 MPH UNTIL 2100. WEST 19 TO 24  
MPH AFTER 0300.  
SMOKE DISPERSAL.....POOR.  
 
TIME (MST) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM  
SKY (%).........9 13 17 8 16 23 22 20 19 18 16 15  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0 0 0 0  
CHC OF PCPN (%).0 0 0 0 0 0 0 0 0 0 0 0  
TEMP............29 27 25 25 24 24 24 23 22 21 20 20  
RH..............68 71 74 71 71 71 72 75 77 81 84 88  
20 FT WIND DIR..NW NW W W W W W W W W W W  
20 FT WIND SPD..8 7 7 7 7 7 7 8 8 9 9 10  
20 FT WIND GUST.17 17 17 17 17 17 17 17 18 20 22 16  
MIX HGT (KFT)...1.3 1.5 1.4 1.5 1.4 1.4 1.5 1.5 1.5 1.5 1.5 1.5  
TRANSP WIND DIR.NW W W W W W W W W W W W  
TRANSP WIND SPD.13 13 10 10 13 14 15 17 18 20 21 22  
VRATE KT-FT/1K..15 16 13 13 15 17 19 22 24 25 27 29  
SMOKEDISPERSION.P P P P P P P P P P P P  
   
WEDNESDAY  
 
SKY/WEATHER.........MOSTLY SUNNY (15-25 PERCENT) UNTIL 0900, THEN  
PARTLY CLOUDY (30-40 PERCENT) UNTIL 1100, THEN  
MOSTLY CLOUDY (60-70 PERCENT). CHANCE OF SNOW  
AFTER 1100 UNTIL 1700, THEN SNOW LIKELY.  
CWR.................7 PERCENT INCREASING TO 42 PERCENT LATE IN THE  
AFTERNOON.  
CHANCE OF PCPN......70 PERCENT.  
MAX TEMPERATURE.....AROUND 44.  
MIN HUMIDITY........51 PERCENT.  
WIND (20 FT)........WEST WINDS 12 TO 21 MPH WITH GUSTS TO AROUND 33  
MPH UNTIL 1600, THEN 19 TO 27 MPH WITH GUSTS TO  
AROUND 35 MPH.  
MIXING HEIGHT.......3600 FT AGL.  
TRANSPORT WINDS.....WEST 22 TO 31 MPH UNTIL 1100, THEN 33 TO 38  
MPH.  
SMOKE DISPERSAL.....POOR UNTIL 0900, THEN FAIR UNTIL 1000, THEN  
GOOD UNTIL 1100, THEN VERY GOOD.  
 
TIME (MST) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........17 18 20 31 42 53 53 53 53 61 70 78  
WEATHER COV..... CHC CHC CHC CHC CHC CHC LKY  
WEATHER TYPE.... SN SN SN SN SN SN SN  
TSTM COV........  
CWR.............0 0 0 0 0 10 10 10 10 10 10 40  
CHC OF PCPN (%).0 0 0 0 0 30 30 30 30 30 30 70  
TEMP............21 23 26 32 38 43 44 43 41 39 37 35  
RH..............89 85 73 63 56 51 51 53 56 61 64 70  
20 FT WIND DIR..W W W W W W W W W W W W  
20 FT WIND SPD..12 12 13 14 16 17 18 18 20 21 22 23  
20 FT WIND GUST.18 18 21 22 25 28 30 30 31 33 35 35  
MIX HGT (KFT)...1.6 1.6 1.7 2.2 2.8 3.4 3.5 3.6 3.7 3.6 3.5 3.3  
TRANSP WIND DIR.W W W W W W W W W W W W  
TRANSP WIND SPD.22 22 22 26 31 36 36 36 36 36 35 35  
VRATE KT-FT/1K..30 31 32 52 76 104 107 110 114 109 105 101  
SMOKEDISPERSION.P P P F G VG VG VG VG VG VG VG  
 
 
FORECASTER...DANIELSON  
REQUESTED BY...KRIS HILLS  
TYPE OF REQUEST...PRESCRIBED  
.TAG 2527714.0/BOU  
.DELDT 12/15/25  
.FORMATTERVERSION 2.0.0  
.EMAIL KRIS.HILLS@USDA.GOV  
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