247  
FNUS76 KPQR 260959  
FWSPQR  
 
SPOT FORECAST FOR FILLY #570...USFS WIF  
NATIONAL WEATHER SERVICE PORTLAND OR  
259 AM PDT THU APR 26 2018  
 
FORECAST IS BASED ON IGNITION TIME OF 1000 PDT ON APRIL 26.  
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER  
SERVICE PORTLAND, OREGON OFFICE.  
   
..THERMAL TROUGH OVER THE MCKENZIE DISTRICT TODAY
 
 
   
DISCUSSION
 
A SURFACE THERMAL TROUGH WILL BE OVER THE BURN  
SITE INTO THE AFTERNOON. THE TROUGH AXIS SHIFTS TO THE  
CASCADE CREST LATE IN THE AFTERNOON OR EARLY EVENING.  
EXPECT LIGHT EAST OR OFFSHORE LOW-LEVEL FLOW OVER THE  
AREA THROUGH THE MORNING. MEANWHILE, THE MARINE LAYER  
WILL CONTINUE TO DEEPEN THROUGH THE DAY AND WILL RESULT  
IN A SHIFT TO ONSHORE LOW-LEVEL FLOW LATE IN THE DAY.  
THE PRESENCE OF THE THERMAL TROUGH WILL RESULT IN ENHANCED  
MIXING HEIGHTS DUE TO THE LOW-LEVEL INSTABILITY. THE  
MARINE AIR FLOODS INTO THE AREA THURSDAY NIGHT AND  
WILL LIKELY EXTEND TO THE CASCADE CREST BY FRIDAY MORNING.  
 
   
TODAY
 
 
SKY/WEATHER.........SUNNY.  
CWR.................0 PERCENT.  
LAL.................1.  
MAX TEMPERATURE.....83-86.  
MIN HUMIDITY........20-25 PERCENT.  
WIND (20 FT)........  
SLOPE/VALLEY.......NORTHEAST TO EAST 2 TO 7 MPH, BECOMING  
MORE UP-SLOPE MID TO LATE MORNING. WIND  
MORE SOUTHWEST TO WEST 4 TO 8 MPH LATE  
IN THE AFTERNOON.  
RIDGETOP...........EAST TO SOUTHEAST 3 TO 8 MPH.  
MIXING HEIGHT.......3500 FT AGL LATE MORNING, INCREASING TO  
5500 FT AGL IN THE AFTERNOON.  
TRANSPORT WINDS.....EAST AROUND 7 MPH.  
HAINES INDEX(HIGH)..3 (VERY LOW).  
HAINES INDEX (MID)..5 (MODERATE).  
RAINFALL AMOUNT.....0.00 INCHES.  
 
TIME 1000 1200 1400 1600 1800  
TEMP 63-66 75-78 83-86 83-86 78-81  
RH 48-55% 28-33% 20-25% 20-25% 27-33%  
WIND VRBL 4 SW 4 SW 5 SW-W 6 SW-W 6  
GUST 7 9 10 10  
 
   
TONIGHT
 
 
SKY/WEATHER.........PARTLY CLOUDY EARLY EVENING THEN  
INCREASING CLOUDS. A SLIGHT CHANCE OF  
SHOWERS AND THUNDERSTORMS IN THE  
EVENING THEN A CHANCE OF SHOWERS.  
CWR.................10 PERCENT.  
LAL.................2.  
MIN TEMPERATURE.....48-51.  
MAX HUMIDITY........75-85 PERCENT.  
WIND (20 FT)........  
SLOPE/VALLEY.......SOUTHWEST TO WEST 5 TO 10 MPH EARLY  
EVENING WITH GUSTS TO 15 MPH. WIND  
BECOMING DRAINAGE LESS THAN 5 MPH AFTER  
DARK. GUSTY AND ERRATIC WIND EXPECTED  
NEAR THUNDERSTORMS.  
RIDGETOP...........NORTHEAST 3 TO 7 MPH, SHIFTING TO WEST  
OVERNIGHT.  
MIXING HEIGHT.......6000 FT AGL, DECREASING TO 1000 FT AGL  
EARLY EVENING.  
TRANSPORT WINDS.....LIGHT WINDS.  
HAINES INDEX(HIGH)..3 (VERY LOW).  
HAINES INDEX (MID)..4 (LOW).  
RAINFALL AMOUNT.....UP TO 0.05 INCHES.  
   
FRIDAY
 
 
SKY/WEATHER.........CLOUDY. SHOWERS LIKELY.  
CWR.................40 PERCENT.  
LAL.................1.  
MAX TEMPERATURE.....54-57.  
MIN HUMIDITY........60-70 PERCENT.  
WIND (20 FT)........  
SLOPE/VALLEY.......VARIABLE TO 5 MPH, BECOMING SOUTHWEST  
TO WEST 5 TO 10 MPH WITH GUSTS TO 15  
MPH IN THE AFTERNOON.  
RIDGETOP...........WEST 4 TO 7 MPH, INCREASING TO 7 TO  
12 MPH WITH GUSTS TO 20 MPH IN THE  
AFTERNOON.  
MIXING HEIGHT.......RISING TO 2500 FT AGL.  
TRANSPORT WINDS.....WEST AROUND 6 MPH.  
HAINES INDEX(HIGH)..2 (VERY LOW).  
HAINES INDEX (MID)..2 (VERY LOW).  
RAINFALL AMOUNT.....0.10 TO 0.25 INCHES.  
 

 
FORECASTER...WEISHAAR  
REQUESTED BY...DIRK ROGERS  
TYPE OF REQUEST...PRESCRIBED  
.TAG 1807870.0/PQR  
.EMAIL DROGERS02@FS.FED.US  
 
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