FNUS75 KSLC 232201
FWSSLC

Spot Forecast for Big Mountain...NUIFC
National Weather Service Salt Lake City UT
401 PM MDT Sun Aug 23 2026

Forecast is based on forecast start time of 1600 MDT on August 23. 
If conditions become unrepresentative...contact the National Weather
Service.

.DISCUSSION...A dry southwesterly flow will continue to mix down
through the remainder of the afternoon and early evening resulting
in gusty winds. Showers and thunderstorms well to the west of the
fire will gradually spread east over the next few hours. Most of
these will remain north of the fire, however there is a 30% chance
these storms pass near or over the fire area during the 1800-2200 
window. Lightning, strong outflow winds in excess of 40 mph, and
heavy rain are all possible with these storms should they impact 
the fire this evening. By late evening winds will become terrain
driven as the nighttime inversion begins to set up. A similar 
pattern is expected Monday, with gusty southwest winds surfacing 
by early afternoon, and a few late afternoon and evening showers 
and thunderstorms possible.


.REST OF TODAY (THROUGH 1800 HOURS)...

Sky/weather.........Mostly sunny (10-20 percent cloud cover). 
CWR.................0 percent. 
Chance of pcpn......10 percent. 
Chance of lightning.6 percent. 
Max temperature.....Around 90. 
Min humidity........16-19 percent. 
Wind (20 ft)........Southwest 5-10 mph with gusts 18-24 mph. 
Mixing height.......12800 ft AGL (80-90th Percentile). 
Transport winds.....Southwest around 20 mph. 

.TONIGHT (1800-0600)...

Sky/weather.........Partly cloudy (45-60 percent cloud cover). A 
                    chance of showers and thunderstorms in the 
                    evening, then a slight chance of showers 
                    overnight. 
CWR.................5 percent. 
Chance of pcpn......30 percent. 
Chance of lightning.20 percent. 
Min temperature.....65-68. 
Max humidity........41-45 percent. 
Wind (20 ft)........Southwest 5-9 mph with gusts to 10 mph early, 
                    becoming downslope/down-drainage 3-7 mph 
                    after 2000. Gusty and erratic outflow winds
                    thunderstorms in the evening. 
Mixing height.......12100 ft AGL decreasing to 500 ft AGL 
                    overnight. 
Transport winds.....Southwest around 15 mph becoming south around 
                    5 mph overnight. 

.MONDAY...

Sky/weather.........Mostly sunny (20-30 percent cloud cover), 
                    becoming partly cloudy with a slight chance
                    of showers after 1500. 
CWR.................0 percent. 
Chance of pcpn......15 percent. 
Chance of lightning.10 percent. 
Max temperature.....Around 90. 
Min humidity........16-20 percent. 
Wind (20 ft)........Southwest winds 6 to 9 mph. 
Mixing height.......12900 ft AGL (80-90th Percentile). 
Transport winds.....Southwest 15 mph. 

$$
Forecaster...Seaman
Requested by...Casey Hansen
Type of request...WILDFIRE
.TAG 2620325.0/SLC
.DELDT 08/23/26
.FormatterVersion 2.0.0
.EMAIL utnuc@firenet.gov,natet@utahcounty.gov