566
FNUS75 KGJT 122026
FWSGJT

Spot Forecast for Derby...Upper Colorado River
National Weather Service Grand Junction CO
226 PM MDT Fri Sep 12 2025

Forecast is based on forecast start time of 1500 MDT on September 12.
If conditions become unrepresentative, contact the National Weather
Service.

.DISCUSSION...There is a chance for showers and storms later today
and into the overnight. The chances for wetting rain are high.
Scattered showers are expected once again tomorrow. Gusty winds and
hail are also possible with the stronger cell. Conditions are more
quiet on Sunday and Monday.

.REST OF TODAY...

Sky/weather.........Mostly cloudy (75-85 percent). Rain showers
                    likely and chance of thunderstorms.
CWR.................50 percent.
Max temperature.....48-53.
Min humidity........65-70 percent.
Wind (20 ft)........South winds 8-15 mph. Gusty and erratic winds
                    expected near thunderstorms.
Smoke dispersal.....Poor (16000 knot-ft).
Mixing height.......1500 ft AGL.
Transport winds.....South 13 mph.
Clearing Index......280.
Chance of thunder...50 percent.

.TONIGHT...

Sky/weather.........Mostly cloudy (60-70 percent). Chance of
                    thunderstorms in the evening. Chance of rain
                    showers through the night.
CWR.................30 percent.
Min temperature.....36-41.
Max humidity........79-84 percent.
Wind (20 ft)........West winds 5-10 mph. Gusty and erratic winds
                    expected near thunderstorms in the evening.
Smoke dispersal.....Poor (0-2000 knot-ft).
Mixing height.......200 ft AGL.
Transport winds.....Southwest 10 mph.
Clearing Index......50.
Chance of thunder...30 percent.

.SATURDAY...

Sky/weather.........Mostly cloudy (75-85 percent). Chance of rain
                    showers and slight chance of thunderstorms in
                    the morning, then rain showers with
                    thunderstorms and snow showers likely in the
                    afternoon.
CWR.................50 percent.
Max temperature.....47-52.
Min humidity........55-60 percent.
Wind (20 ft)........Southwest winds 8-15 mph. Gusty and erratic
                    winds expected near thunderstorms.
Smoke dispersal.....Poor (6000-25000 knot-ft).
Mixing height.......2300 ft AGL.
Transport winds.....Southwest 11 mph.
Clearing Index......90 increasing to 480 in the afternoon.
Chance of thunder...55 percent.

$$
Forecaster...Kris Sanders
Requested by...Pfeifer, Matthew
Type of request...WILDFIRE
.TAG 2521881.0/GJT
.DELDT 09/12/25
.FormatterVersion 2.0.0
.EMAIL bokarski@bm.gov,mpfeifer@blm.gov