textproduct: Grand Junction

KEY MESSAGES

- Another round of below freezing temperatures are forecast for many of the valleys this morning.

- A push of moisture and warmer temperatures will lead to afternoon shower and thunderstorm activity over the southern and central Colorado mountains Monday and Tuesday, and in the northern Colorado mountains Wednesday.

- Gusty winds and near critical fire weather conditions will be potential hazards Wednesday as the next upstream system approaches and brings a change to end out the week.

DISCUSSION

Issued at 1022 PM MDT Sat Apr 18 2026

In the wake of the passing cold front from Friday, we remain situated under a cooler air mass which makes for the continued below average temperatures this morning. Freeze Warnings remain in effect until 9 AM MDT for nearly all of the valleys, with the exception of the lower desert valleys and Grand Valley. Synoptic scale ridging begins to amplify over the region beginning on Sunday, with an upstream closed low still situated off the West Coast. The subsidence associated with this ridge will suppress cloud cover for the day and initiate a warming trend for the beginning of the week, pushing temperatures above the seasonal average.

The aformentioned cold front has made its way down to the Texas Gulf Coast. As a result of its return flow, sub-tropical moisture will advect into the Four Corners area early Monday. This moisture lingers over the area through Tuesday looking to bring isolated to widely scattered afternoon showers for the southern and central mountains. I would not rule out the possibility for isolated thunderstorms as daytime heating will have the ability to promote stronger convection. Aside from that, expect temperatures to warm to 10-15 degrees above normal Monday and Tuesday.

Attention then shifts to the closed low continuing to push towards the Intermountain West Wednesday. Ahead of this system, pressure gradient contours will be tightly packed aloft, making for strong upper level winds. As daytime heating occurs and the surface inversion breaks down, expect those strong upper level winds to mix down to the surface making for periods of strong winds gusting 40 to 55 mph through most of the valleys across the region. These winds combined with the dry air that will move in across the region will promote near critical fire weather conditions. Stay tuned for updates on this.

PATTERN SHIFT LATE WEEK:

Moving forward, a cooler and wetter weather pattern will be ushered in. There is still uncertainty with the specific track of this low pressure system, but it appears to bring back temperatures slightly below normal and higher elevation snowfall for the northern and central mountains Thursday into Friday. Impacts for this late week event look to be more below freezing temperatures for the high valleys and temporary winter driving conditions over some of the mountain passes.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 531 AM MDT Sun Apr 19 2026

High pressure will continue to produce VFR conditions at the terminals through this period. Some scattered to broken high clouds will spill over the ridge early this morning, with clearing skies expected Sunday afternoon. Winds will pick up a bit Sunday with some afternoon gusts to around 20 mph near terrain, then sitting down Sunday evening again to light and variable. Mid and upper level ceilings begin to invade from the southwest across the Four Corners late tonight. Breakpoint conditions are not expected.

GJT WATCHES/WARNINGS/ADVISORIES

CO...Freeze Warning until 9 AM MDT this morning for COZ001-002-007- 008-011-020>023. Freeze Watch from this evening through Monday morning for COZ002-008. UT...Freeze Warning until 9 AM MDT this morning for UTZ024.