203  
FNUS75 KRIW 212218  
FWSRIW  
 
SPOT FORECAST FOR TANNERITE FIRE...BLM CAD  
NATIONAL WEATHER SERVICE RIVERTON WY  
418 PM MDT WED AUG 21 2019  
 
FORECAST IS BASED ON FORECAST START TIME OF 0600 MDT ON AUGUST 22.  
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER  
SERVICE.  
 
...RED FLAG WARNING IN EFFECT FROM NOON THURSDAY TO 8 PM MDT  
FRIDAY...  
   
DISCUSSION
 
LIGHT TO MODERATE WINDS WILL OCCUR FOR THE REST OF THIS  
AFTERNOON. CONDITIONS ARE EXPECTED TO REMAIN DRY, WITH CRITICALLY  
LOW RH VALUES CONTINUING. A COLD FRONT IS EXPECTED TO CROSS  
THE AREA ON THURSDAY. THIS WILL BRING WARMER AND DRIER AIR AHEAD OF  
THE FRONT. STRONG WINDS ARE EXPECTED THURSDAY AS WELL AS ON  
FRIDAY BEHIND THE FRONT. THIS IN ADDITION TO RHS IN THE LOW TEENS HAS  
RESULTED IN THE ISSUANCE OF A RED FLAG WARNING FOR THURSDAY AND FRIDAY  
AFTERNOON AND EARLY EVENING.  
   
..THUNDERSTORMS IMPLY STRONG GUSTY AND ERRATIC WINDS
 
   
..HAINES INDEX IS HIGH LEVEL HAINES BOTH DAY AND NIGHT
 
 
FORECASTER...LIPSON  
   
THURSDAY
 
 
SKY/WEATHER.........PARTLY CLOUDY (45-55 PERCENT) THEN BECOMING  
MOSTLY CLOUDY (70-80 PERCENT).  
MAX TEMPERATURE.....77-79.  
MIN HUMIDITY........14-16 PERCENT.  
20-FOOT WINDS.......UPSLOPE/UPVALLEY 5-9 MPH BECOMING WEST SOUTHWEST  
10 MPH WITH GUSTS TO AROUND 18 MPH AS WELL AS  
A FEW ISOLATED GUSTS OF 25 MPH BY 1500. WINDS WILL  
THEN SHIFT TO THE NORTHWEST AT THE SAME SPEEDS  
BY 1600.  
RIDGE TOP WINDS.....EAST AROUND 10 MPH SHIFTING TO THE SOUTHWEST IN  
THE LATE MORNING AND EARLY AFTERNOON, THEN  
SHIFTING TO THE WEST AROUND 20 MPH LATE IN THE  
AFTERNOON.  
LAL.................1.  
CHC OF WETTING RAIN.ZERO PERCENT.  
HAINES INDEX........5 OR MODERATE POTENTIAL FOR LARGE PLUME  
DOMINATED FIRE GROWTH.  
MIXING HEIGHT.......11300 FT AGL.  
TRANSPORT WINDS.....EAST AROUND 8 MPH SHIFTING TO THE SOUTHWEST 10  
TO 15 MPH IN THE LATE MORNING AND EARLY  
AFTERNOON, THEN INCREASING TO AROUND 22 MPH  
LATE IN THE AFTERNOON.  
SMOKE DISPERSAL.....POOR TO FAIR INCREASING TO EXCELLENT.  
 
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........42 43 43 44 50 57 63 70 76 82 80 77  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0 0 0 0  
LAL.............1 1 1 1 1 1 1 1 1 1 1 1  
TEMP............48 50 61 66 70 72 75 76 77 77 77 76  
RH..............59 56 41 33 28 24 21 18 17 17 19 18  
20 FT WIND DIR..NE E SE S S S SW SW SW W W W  
20 FT WIND SPD..4 3 4 4 4 6 7 8 9 11 10 11  
20 FT WIND GUST.5 5 5 5 7 9 16 18 22 21 22  
MIX HGT (KFT)...0.6 0.6 0.6 1.7 1.7 1.7 8.2 8.2 8.2 12 12 12  
TRANSP WIND DIR.E E E S S S SW SW SW SW SW SW  
TRANSP WIND SPD.8 8 8 10 10 10 15 15 15 22 22 22  
HAINES INDEX....5 5 5 5 5 5 5 5 5 5 5 5  
SDSPL KT-FT/10004 4 4 15 15 15 106 106 106 224 224 224  
   
THURSDAY NIGHT
 
 
SKY/WEATHER.........MOSTLY CLOUDY (65-75 PERCENT) THEN BECOMING  
PARTLY CLOUDY (35-45 PERCENT).  
MIN TEMPERATURE.....43-46.  
MAX HUMIDITY........63-66 PERCENT.  
20-FOOT WINDS.......WEST WINDS AROUND 8 MPH WITH GUSTS TO AROUND 13  
MPH EARLY IN THE EVENING BECOMING  
DOWNSLOPE/DOWNVALLEY 4-7 MPH BY 1900 FOR THE  
REST OF THE NIGHT, EXCEPT NORTHWEST 10 TO 20 MPH  
BETWEEN 2300 AND 0200.  
RIDGE TOP WINDS.....NORTH 10 TO 15 MPH SHIFTING TO THE NORTHEAST  
AROUND 5 MPH AFTER 3 AM.  
LAL.................1.  
CHC OF WETTING RAIN.ZERO PERCENT.  
HAINES INDEX........3 TO 4 OR VERY LOW TO LOW POTENTIAL FOR LARGE  
PLUME DOMINATED FIRE GROWTH.  
MIXING HEIGHT.......10700 FT AGL UNTIL 2100, THEN 600 FT AGL.  
TRANSPORT WINDS.....WEST AROUND 21 MPH BECOMING NORTH 7 TO 10 MPH  
IN THE LATE EVENING AND OVERNIGHT.  
SMOKE DISPERSAL.....EXCELLENT DECREASING TO POOR IN THE LATE  
EVENING AND OVERNIGHT.  
 
TIME (MDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM  
SKY (%).........74 70 56 50 46 37 32 30 25 23 23 22  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0 0 0 0  
LAL.............1 1 1 1 1 1 1 1 1 1 1 1  
TEMP............76 73 68 62 59 56 54 54 52 50 46 44  
RH..............18 21 26 33 39 44 48 49 53 57 62 66  
20 FT WIND DIR..W W NW NW NW NW NW N N NE NE NE  
20 FT WIND SPD..8 6 6 5 4 4 4 3 3 2 2 2  
20 FT WIND GUST.16 13 10 9 7 7 7  
MIX HGT (KFT)...11 11 11 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6  
TRANSP WIND DIR.W W W NW NW NW N N N N N N  
TRANSP WIND SPD.21 21 21 9 9 9 10 10 10 7 7 7  
HAINES INDEX....4 4 4 4 4 4 3 3 3 3 3 3  
SDSPL KT-FT/1000192 192 192 5 5 5 5 5 5 3 3 3  
   
FRIDAY
 
 
SKY/WEATHER.........MOSTLY SUNNY (15-25 PERCENT).  
MAX TEMPERATURE.....78-80.  
MIN HUMIDITY........14-17PERCENT.  
20-FOOT WINDS.......UPSLOPE/UPVALLEY 5-9 MPH, BECOMING WEST SOUTHWEST  
14 MPH TO 24 MPH BY 1400.  
RIDGE TOP WINDS.....EAST AROUND 5 MPH SHIFTING TO THE SOUTHWEST 10  
TO 15 MPH IN THE LATE MORNING AND AFTERNOON.  
LAL.................1.  
CHC OF WETTING RAIN.ZERO PERCENT.  
HAINES INDEX........3 TO 4 OR VERY LOW TO LOW POTENTIAL FOR LARGE  
PLUME DOMINATED FIRE GROWTH.  
MIXING HEIGHT.......7800 FT AGL.  
TRANSPORT WINDS.....NORTHEAST AROUND 6 MPH SHIFTING TO THE SOUTH  
AROUND 8 MPH LATE IN THE MORNING, THEN SHIFTING  
TO THE WEST 12 TO 15 MPH IN THE AFTERNOON.  
SMOKE DISPERSAL.....POOR TO GOOD INCREASING TO EXCELLENT LATE IN  
THE AFTERNOON.  
 
TIME (MDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........22 19 13 10 11 13 14 16 19 21 24 29  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............0 0 0 0 0 0 0 0 0 0 0 0  
LAL.............1 1 1 1 1 1 1 1 1 1 1 1  
TEMP............44 48 53 59 64 67 69 71 72 73 74 74  
RH..............66 61 54 45 38 33 30 27 25 24 22 21  
20 FT WIND DIR..NE E S SW SW SW SW SW SW SW SW W  
20 FT WIND SPD..2 2 2 2 3 4 5 6 6 7 8 8  
20 FT WIND GUST. 7 9 10 13 14 16 16  
MIX HGT (KFT)...0.6 0.6 0.6 2.2 2.2 2.2 5.7 5.7 5.7 8.1 8.1 8.1  
TRANSP WIND DIR.NE NE NE S S S W W W W W W  
TRANSP WIND SPD.6 6 6 8 8 8 12 12 12 15 15 15  
HAINES INDEX....3 3 3 3 3 3 4 4 4 4 4 4  
SDSPL KT-FT/10003 3 3 15 15 15 57 57 57 106 106 106  
   
FORECAST DAYS 3 THROUGH 5
 
   
FRIDAY NIGHT
 
 
PARTLY CLOUDY. LOWS IN THE MID 40S. WINDS GENERALLY LESS THAN  
10 MPH.    
SATURDAY
 
 
PARTLY CLOUDY. LOWS IN THE MID 40S. HIGHS IN THE UPPER 70S. WINDS  
GENERALLY LESS THAN 10 MPH.    
SUNDAY
 
 
CLEAR. LOWS IN THE LOWER 40S. HIGHS IN THE MID 70S. WINDS  
GENERALLY LESS THAN 10 MPH.    
MONDAY
 
 
CLEAR. LOWS IN THE LOWER 40S. HIGHS IN THE LOWER 70S. WINDS  
GENERALLY LESS THAN 10 MPH.  
 

 
FORECASTER...LIPSON  
REQUESTED BY...JON ZIEGLER  
TYPE OF REQUEST...WILDFIRE  
.TAG 1913950.5/RIW  
.DELDT 08/21/19  
.EMAIL WYCPC@FIRENET.GOV  
 
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