textproduct: Grand Junction

KEY MESSAGES

- Hot, dry and windy conditions continue today and Saturday, possibly into Sunday. Red Flag Warnings are in effect for portions of the area meeting criteria where the fuels are critical for today and Saturday.

- A deep trough dips into the Great Basin Sunday afternoon, bringing precipitation chances to northeast UT and northwest CO, becoming more widespread Sunday evening into Monday.

- Mountain snow looks to accompany this system Sunday night into Monday morning.

- Freezing temperatures are expected to impact portions of the region Monday and Tuesday night.

DISCUSSION

Issued at 1218 PM MDT Fri May 15 2026

CRITICAL FIRE WEATHER THROUGH SATURDAY:

Winds will increase today as a leading jet streak ahead of a broad low pressure trough over British Columbia slides over northeast Utah and northwest Colorado. This has prompted Red Flag Warnings as gusty winds to 30 mph and low relative humidity in the single digits will lead to critical fire weather conditions for the NE Utah and NW Colorado zones along and north of the I-70 corridor as well as Gunnison Basin this afternoon. On Saturday, the focus for critical fire weather conditions will shift southward along and south of I-70 due to increasing moisture across the north with even stronger southwest gradient winds as the low pressure system deepens and carves out a trough across the Great Basin. So the combination of low relative humidity and gusty winds in the 30 to 40 mph range has prompted an upgrade of the Fire Weather Watch to a Red Flag Warning for Saturday for those critical zones along and south of I-70, which now includes COZ203 and 205 (Colorado River zones) below 8000 feet due to a recent fuels update to critical status. Showers will develop Saturday afternoon mainly across northeast Utah and northwest Colorado with mostly virga expected due to the antecedent dry air mass still in place, but this should allow for relative humidity to increase above critical thresholds north of I-70, hence why they are not included in the Red Flag. Temperatures through Saturday will remain 10 to 15 degrees above normal with a drop to near normal by Sunday as the deepening trough pushes through our area and precipitation increases.

MOISTURE INCREASES SUNDAY AND MONDAY:

Precipitation and moisture will increase heading into Sunday, with the focus for shower and storm activity along and north of I-70, mainly across northeast Utah and northwest Colorado. Breezy winds will be focused across southeast Utah and southwest Colorado where the drier air remains, so there is potential that critical fire weather conditions could extend into Sunday, dependent on the fuels status. Precipitation will make it southward towards the Four Corners for widespread shower activity Sunday evening into Monday, so this appears to be the more favored period for precipitation as well as cooler temperatures. Temperatures drop to around 10 to 20 degrees below normal Monday as the trough lifts northeast across eastern Utah and western Colorado as a negatively tilted trough and several vort maxes rotating through, so Sunday evening into Monday appears to be the most active in terms of shower/storm activity. There is potential for mountain snow Sunday night into Monday morning, focused on the eastern Uintas and northern Park Range mountains at this time for better accumulations. Regardless, travel on mountain passes could be a bit dicey Monday morning. The trough axis is expected to lift out of the region Monday night with some showers hanging on Tuesday morning across the northern mountains.

TUESDAY AND BEYOND:

Precipitation will hang up on the Divide Tuesday and Wednesday with some afternoon showers left over in the northwest flow behind the departing trough. The rest of the area should begin to dry out Tuesday and Wednesday but below normal temperatures remain. Freezing temperatures will likely impact portions of the CWA Tuesday and Wednesday morning behind this cold front. Afternoon highs will trend down from near normal Sunday to well below normal Monday and Tuesday. Transitional ridging brings things back near normal on Wednesday and Thursday with a potential warm up in the works as high pressure crosses the Rockies.

AVIATION /18Z TAFS THROUGH 18Z SATURDAY/

Issued at 1125 AM MDT Fri May 15 2026

VFR conditions are expected to prevail through the TAF period. West to northwesterly winds are already gusting at some terminals and will become more widespread into the afternoon hours. Gusts will be within the 20-25 kt range. Gusts die down this evening, with terrain driven patterns prevailing through the overnight period. Skies will start off mostly clear, with some mid level cloud development expected into the afternoon, but nothing of concern.

FIRE WEATHER

Issued at 1218 PM MDT Fri May 15 2026

Winds will increase across the north today ahead of an approaching disturbance where coverage of gusty winds and low relative humidity has prompted the issuance of a Red Flag Warning for NE Utah and NW Colorado Fire Zones where fuels are critical (UTZ486-487, COZ200-202-293). Also, added the I-70 corridor/Colorado River zones (COZ203-205) below 8000 feet due to a recent fuels status change to critical. Conditions remain dry mainly along and south of I-70 on Saturday with winds increasing (gusts 30 to 40 mph) and becoming more widespread, prompting the Fire Weather Watch to be upgraded to a Red Flag Warning for UTZ490, COZ203 and 205 below 8000 feet, 290 and 292 where coverage and duration is best. Conditions are more borderline across the north in terms of RH. Humidity increases late Saturday into Sunday for the northern half of the CWA, with better chances of widespread precipitation and wetting rain Sunday and Monday. However, low relative humidities and strong winds on Sunday could drive more critical fire weather headlines for COZ290, 292, and UTZ490.

GJT WATCHES/WARNINGS/ADVISORIES

CO...Red Flag Warning until 8 PM MDT this evening for COZ200-202- 203-205-293. Red Flag Warning from noon to 8 PM MDT Saturday for COZ203-205- 290-292. UT...Red Flag Warning until 8 PM MDT this evening for UTZ486-487. Red Flag Warning from noon to 8 PM MDT Saturday for UTZ490.