517
FNUS76 KOTX 202258
FWSOTX

Spot Forecast for Hill Loop Fire...NEWICC
National Weather Service Spokane WA
358 PM PDT Thu Aug 20 2026

Forecast is based on forecast start time of 1600 PDT on August 20.
...HEAT ADVISORY IN EFFECT FROM 11 AM TO 10 PM PDT FRIDAY...
...FIRE WEATHER WATCH IN EFFECT FROM SATURDAY MORNING THROUGH
SUNDAY MORNING FOR LIGHTNING AND GUSTY OUTFLOW WINDS...

.DISCUSSION...
Light upslope or southerly winds will continue into the early evening.
Winds on the lower slopes (below 3000 feet) will decouple and become light
and variable by 2000 as inversions develop.  Southerly winds will continue
near the hill top (3000 feet) through 2200 before decreasing less than 5 mph.
Conditions will remain warm and dry overnight with poor recoveries.
Hot, dry conditions will be in place Friday with breezy afternoon winds.
A chance for showers and slight thunderstorms arrive late Friday night into
Saturday.

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).
***************************************************************

.REST OF TODAY...

Sky/weather.........Sunny. Haze and smoke.
CWR.................0 percent.
Chance of lightning.0 percent.
Max temperature.....90.
Min humidity........14 percent.
Wind (20 ft)........Southerly winds 3 to 8 mph.
Mixing height.......8000 ft AGL.
Transport winds.....Southwest around 8 mph.
Ventilation Index...Moderate (466).

.TONIGHT...

Sky/weather.........Mostly clear. Haze and patchy smoke.
CWR.................0 percent.
Chance of lightning.0 percent.
Min temperature.....63.
Max humidity........34-39 percent.
Wind (20 ft)........South winds 2 to 6 mph becoming downslope or north 1 to 4 mph.
Mixing height.......Inversions developing 2000-2100.  MH falling near surface.
Transport winds.....South around 5 mph shifting to the northeast
                    overnight.
Ventilation Index...Moderate (222) decreasing to low (18)
                    overnight.

.FRIDAY...

Sky/weather.........Mostly sunny. Haze and patchy smoke.
CWR.................0 percent.
Chance of lightning.0 percent.
Max temperature.....93.
Min humidity........12-16 percent.
Wind (20 ft)........Downslope or north winds 1 to 4 mph becoming upslope
                    or south 3 to 8 mph.
Mixing height.......7500 ft AGL in the afternoon.
Transport winds.....Northeast 2 mph becoming south 5 mph.
Ventilation Index...Moderate (253).

$$
Forecaster...SB
Requested by...Dispatch
Type of request...WILDFIRE
.TAG 2620123.0/OTX
.DELDT 08/20/26
.FormatterVersion 2.0.0
.EMAIL WANEC@firenet.gov