608
FNUS76 KOTX 211526
FWSOTX
SPOT FORECAST FOR COTTONWOOD DIVIDE...NEWICC
NATIONAL WEATHER SERVICE SPOKANE WA
826 AM PDT FRI AUG 21 2026
FORECAST IS BASED ON FORECAST START TIME OF 0800 PDT ON AUGUST 21.
...HEAT ADVISORY IN EFFECT FROM 11 AM THIS MORNING TO 10 PM PDT
THIS EVENING...
DISCUSSION
CONDITIONS WILL BE WARM AND DRY FRIDAY WITH EAST WINDS LESS THAN
10 MPH. MIDDLE AND HIGH LEVEL CLOUDS INCREASE THROUGH THE DAY WITH
FILTERED SUNSHINE. SATURDAY WILL BRING AN INCREASE IN WINDS,
MOISTURE, AND CHANCES FOR SHOWERS AND THUNDERSTORMS. 10% CHANCE
FOR SPRINKLES IN THE MORNING AND EARLY AFTERNOON INCREASING TO A
25% CHANCE OF SHOWERS AND THUNDERSTORMS BY THE MIDDLE OF THE
AFTERNOON INTO THE EVENING. WINDS WILL INCREASE OUT OF THE EAST IN
THE LATTER HALF OF THE MORNING INTO THE EARLY AFTERNOON BEFORE
SHIFTING TO THE SOUTH TO SOUTHWEST WITH A COLD FRONT.
IF CONDITIONS BECOME UNREPRESENTATIVE, CONTACT THE NATIONAL WEATHER
SERVICE.
***************************************************************
FORECASTS FOR 20 FOOT WIND SPEEDS (VALLEYS AND RIDGE TOPS) ARE
10 MINUTE AVERAGES REFLECTING RAWS WIND.
***VENTILATION INDEX IS DERIVED FROM TRANSPORT WIND
MULTIPLIED BY THE MIXING HEIGHT DIVIDED BY 100.
CATEGORIES: LOW (< 200), MODERATE (200-500),
HIGH (500-800), AND VERY HIGH (> 800).
***************************************************************
TODAY
SKY/WEATHER.........MOSTLY SUNNY. HAZE AND PATCHY SMOKE.
CWR.................0 PERCENT.
CHANCE OF LIGHTNING.0 PERCENT.
MAX TEMPERATURE.....AROUND 90.
MIN HUMIDITY........17-22 PERCENT.
WIND (20 FT)........EAST 4 TO 7 MPH.
MIXING HEIGHT.......5500 FT AGL IN THE AFTERNOON.
TRANSPORT WINDS.....EAST AROUND 5 MPH.
VENTILATION INDEX...MODERATE (213).
TONIGHT
SKY/WEATHER.........CLOUDY. HAZE AND PATCHY SMOKE OVERNIGHT.
CWR.................0 PERCENT.
CHANCE OF LIGHTNING.5 PERCENT.
MIN TEMPERATURE.....AROUND 66.
MAX HUMIDITY........46 PERCENT.
WIND (20 FT)........EAST 5 TO 8 MPH SHIFTING TO THE NORTHEAST
5 TO 8 MPH AROUND 1900 HOURS. DECREASING TO
NORTHEAST 2 TO 5 MPH BETWEEN 0200-0300 HOURS.
MIXING HEIGHT.......2500 FT AGL FALLING TO NEAR SURFACE BETWEEN
1900-2000 HOURS.
TRANSPORT WINDS.....NORTHEAST 5 TO 9 MPH.
VENTILATION INDEX...LOW (108).
SATURDAY
SKY/WEATHER.........SUNNY THEN BECOMING PARTLY SUNNY. 10 PERCENT CHANCE
OF SPRINKLES IN THE MORNING AND EARLY AFTERNOON
INCREASING TO A 25 PERCENT CHANCE OF SHOWERS AND
A 15 PERCENT CHANCE OF THUNDERSTORMS AFTER 1600 HOURS.
CWR.................0 PERCENT.
CHANCE OF LIGHTNING.10 PERCENT IN THE MORNING INCREASING TO 15 PERCENT
CHANCE IN THE MIDDLE OF THE AFTERNOON.
MAX TEMPERATURE.....AROUND 87.
MIN HUMIDITY........22-27 PERCENT.
WIND (20 FT)........SOUTHEAST TO SOUTH 2 TO 5 MPH AROUND 0600 HOURS SHIFTING
TO THE EAST 5 TO 10 MPH AROUND 0800 HOURS. WINDS SHIFTING
TO THE SOUTH 5 TO 10 MPH AROUND 1400 HOURS THEN TO THE
SOUTHWEST 7 TO 12 MPH AROUND 1600 HOURS. WIND GUSTS UP TO
20 MPH IN THE AFTERNOON. GUSTY AND ERRATIC WINDS UP TO
35 MPH WITH ANY NEARBY THUNDERSTORMS.
MIXING HEIGHT.......10000 FT AGL IN THE AFTERNOON.
TRANSPORT WINDS.....NORTHEAST AROUND 10 MPH SHIFTING TO THE SOUTH
AROUND 13 MPH IN THE AFTERNOON.
VENTILATION INDEX...MODERATE (297) INCREASING TO VERY HIGH (1555)
IN THE AFTERNOON.
FORECASTER...VT
REQUESTED BY...HAYLEY ELLIOTT
TYPE OF REQUEST...WILDFIRE
.TAG 2620170.0/OTX
.DELDT 08/21/26
.FORMATTERVERSION 2.0.0
.EMAIL WANEC@FIRENET.GOV,DARREN.FOSTER@DNR.WA.GOV
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