Area Forecast Discussion

KEY MESSAGES

- Some high valleys will experience sub-freezing temperatures again tonight. - Showers and thunderstorms are possible in the southern and central mountains on Monday and Tuesday afternoon. - Wind gusts of 40-55 mph will be common across the area on Wednesday afternoon.

DISCUSSION

Issued at 1018 AM MDT Sun Apr 19 2026

Synoptic scale ridging has begun to amplify over the region, with a 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.

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. A few thunderstorms will be possible as well Monday afternoon. 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. Expect those strong upper level winds to mix down to the surface making for periods of winds gusting 40 to 55 mph through most of the valleys across the region.

PATTERN SHIFT LATE WEEK:

Moving forward, a cooler and wetter weather pattern will be ushered in the low pressure system out west. It will 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 /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1018 AM MDT Sun Apr 19 2026

High pressure will maintain VFR conditions across wrn CO and ern UT TAF sites through Monday morning. Some high lvl moisture will pass across the region this afternoon, generating only limited upper lvl cloud cover. However, mid and upper level ceilings begin to invade from the southwest across the Four Corners late tonight and early Monday. Winds will increase some this afternoon with gusts to around 20 mph near terrain, before winds diminish this evening to mainly light and variable.

GJT WATCHES / WARNINGS / ADVISORIES

CO...Freeze Warning from 10 PM this evening to 9 AM MDT Monday for COZ002-008. UT...None.