240
FNUS75 KBOI 201258
FWSBOI

Spot Forecast for Alder Creek RX...BLM
National Weather Service Boise ID
558 AM MST Thu Nov 20 2025

Forecast is based on ignition time of 1126 MST on November 20.
If conditions become unrepresentative...contact the National Weather
Service.

Please contact our office at (208)334-9060, if you have questions
or concerns with this forecast.

...SHOWERS TODAY ENDING LATER THIS AFTERNOON...

.DISCUSSION...
Light rain showers through this afternoon with passage of a low
pressure system to the west. Light winds northerly winds today.
Inversion developing on Friday will bring valley status/fog and
poor mixing into the weekend. Mixing heights will remain between
1000 and 2000 feet with light transport winds. A weak cold front
on Monday could be enough to break the inversion for Tuesday.

.REST OF TODAY...

Sky/weather.........Cloudy with a 30 percent chance of rain
                    showers.
Max temperature.....37 to 42.
Min humidity........88 to 93 percent.
CWR.................20 percent.
Wind - 20 foot......Northwest around 6 mph.
Mixing height.......1500 ft AGL.
Transport winds.....North around 10 mph.
Ventilation Index...150 poor.

.TONIGHT...

Sky/weather.........Mostly cloudy in the evening then becoming
                    partly cloudy overnight.
Min temperature.....29 to 34.
Max humidity........90 to 100 percent.
CWR.................0 percent.
Wind - 20 foot......North 3 to 6 mph.
Mixing height.......100 ft AGL.
Transport winds.....Northwest around 5 mph.
Ventilation Index...5 poor.

.FRIDAY...

Sky/weather.........Sunny.
Max temperature.....41 to 46.
Min humidity........62 to 67 percent.
CWR.................0 percent.
Wind - 20 foot......West around 6 mph.
Mixing height.......1500 ft AGL.
Transport winds.....West around 5 mph.
Ventilation Index...75 poor.

$$
Forecaster...Smith
Requested by...Rachel Howes
Type of request...PRESCRIBED
.TAG 2526314.1/BOI
.DELDT 11/20/25
.FormatterVersion 2.0.0
.EMAIL orbic@firenet.gov