National Weather Service United States Department of Commerce

COZ205-182315-
COZ205-182315-
Colorado River Headwaters-
109 AM MDT Thu Jun 18 2026

Fire Weather Planning Forecast for Wrn Colorado and Ern Utah
National Weather Service Grand Junction CO
109 AM MDT Thu Jun 18 2026

.DISCUSSION...

Region-wide minimum relative humidity will stay below 15% 
Thursday and Friday with many locations hitting single digits. 
However, westerly winds will have notably weakened with peak 
afternoon gusts expected to reach 18-25 mph and localized areas 
reaching 30 mph. As such, critical fire weather conditions are 
more scattered over the next 48 hours. Another bout of powerful 
westerly gusts returns on Saturday though with peak gusts of 30-45
mph, prompting widespread critical fire weather concerns.

...GUSTY ERRATIC WINDS CAN BE EXPECTED NEAR ANY SHOWERS
OR THUNDERSTORMS...
...THE SMOKE DATA IS CALCULATED FROM AN AVERAGE AT 6000 FEET MSL...


.TODAY...
Sky/weather.........Mostly sunny (10-20%). 
Chc of lightning....0 percent. 
Max temperature.....77-87 F. 
Min humidity........5-10%. 
20-foot winds.......Downslope/downvalley 3 to 6 mph becoming 
                    upslope/upvalley 4 to 8 mph by 1100.
CWR.................0 percent. 
15K Ft MSL Winds....West 20 to 30 mph becoming northwest 15 to 20 
                    mph in the afternoon. 
Mixing Height.......1500 ft AGL until 0900, then 11500 ft AGL. 
Transport Winds.....West 5 to 10 mph. 
Smoke dispersal.....Poor until 0900. Very good after 1200. 

.TONIGHT...
Sky/weather.........Mostly clear (20-30%). 
Chc of lightning....0 percent. 
Min temperature.....49-59 F. 
Max humidity........26-36%. 
20-foot winds.......Upslope/upvalley 4 to 8 mph becoming 
                    downslope/downvalley 3 to 6 mph by sunset.
CWR.................0 percent. 
15K Ft MSL Winds....West 15 to 20 mph increasing to 20 to 25 mph 
                    after midnight. 
Mixing Height.......9500 ft AGL until 2000, then 1000 ft AGL. 
Transport Winds.....Northwest 5 to 10 mph until 2400, then 
                    southeast. 
Smoke dispersal.....Good until 2100, then poor. 

.JUNETEENTH...
Sky/weather.........Mostly sunny (10-20%) until 1200, then partly 
                    cloudy (30-40%). 
Chc of lightning....0 percent. 
Max temperature.....79-89 F. 
Min humidity........6-11%. 
20-foot winds.......Upslope/upvalley winds 4 to 8 mph. Localized 
                    gusts up to 25 mph in the afternoon. 
CWR.................0 percent. 
15K Ft MSL Winds....West 15 to 20 mph decreasing to 10 to 15 mph in 
                    the afternoon. 
Mixing Height.......1000 ft AGL until 0900. 15500 ft AGL after 
                    1000. 
Transport Winds.....West 5 mph until 1200, then 10 to 15 mph. 
Smoke dispersal.....Poor until 0900. Excellent after 1200. 

.FORECAST FOR DAY 3 THROUGH 7...
.SATURDAY...Mostly clear. Lows 49-59. Highs 76-86. West winds
10 to 20 mph with gusts to  45 mph. 
.SUNDAY...Mostly clear. Isolated showers and thunderstorms. Lows
43-53. Highs 72-82. West winds 10 to 20 mph with gusts to 
45 mph. 
.MONDAY...Mostly clear. Isolated showers and thunderstorms. Lows
43-53. Highs 74-84. West winds 10 to 20 mph with gusts to 
30 mph. 
.TUESDAY...Mostly clear. Lows 44-54. Highs 77-87. 
.WEDNESDAY...Mostly clear. Lows 46-56. Highs 78-88.