textproduct: Grand Junction

KEY MESSAGES

- Valley fog is likely through noon and will be dense at times. Watch out for slick roads and rapidly changing visibilities on area roadways!

- Unsettled weather continues through mid week, with valley rain and mountain snow showers possible. Unseasonably warm temperatures will limit snow accumulations.

- Confidence is increasing that a much colder airmass will move in for the late week period, bringing near to below normal temperatures and increased chances for snow.

UPDATE

Issued at 1030 AM MST Sat Jan 3 2026

Patchy dense fog and low stratus continues through noon with conditions gradually improving across the region. Watch out for rapidly changing visibilities on area roadways!

SHORT TERM /THROUGH SUNDAY/

Issued at 204 AM MST Sat Jan 3 2026

Precipitation has, for the most part, come to an end across eastern Utah and western Colorado. Lingering light snow showers over the Park Range will finally taper off in the next few hours as flow shifts from northwesterly to southwesterly. Skies have remained mostly clear so far tonight, which has helped temperatures to cool and for all the moisture now trapped in the valleys to condense into fog and low stratus. This fog will be dense in spots, and where temperatures are below freezing, freezing fog could lead to slick roads. Some of this fog will lift over the next several hours as high level clouds filter in from the west, disrupting the favorable radiational cooling conditions. However, be mindful if out driving this morning all the same, as road conditions and visibility could change rapidly.

Clouds will continue to increase through the day as the southwesterly flow aloft taps into a warm, moist Pacific airmass. This will also keep temperatures mild, with highs remaining 10-15 degrees above normal. Tonight, a weak shortwave and increasing southwesterly jet will provide just a touch of extra lift, on top of favorable southwesterly orographics and ample moisture, to trigger a few light mountain snow showers that linger through the day tomorrow. Accumulations will be light, if any, with up to an inch expected at the highest elevations along the Divide. Elsewhere, tomorrow will be another quiet, warm, and partly to mostly cloudy day. Temperatures tomorrow afternoon will the be warmest we've seen this week, with highs approaching 20 degrees above normal in spots.

LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/

Issued at 204 AM MST Sat Jan 3 2026

West Coast troughing will, once again, put us under strong southwesterly flow beneath a potent jet max Sunday night into Monday morning. Overnight lows Monday morning look more like seasonal afternoon highs here on the West Slope. This warm trend sticks around for a few days early next week with some ebb and flow in temperatures thanks to cloud cover and precipitation. Snow levels fluctuate some, but 6000-7000 feet seems to be the sweet spot for now. Though, I do suspect these could be a little low, given the warm air mass. Nonetheless, a few shortwave ripples will ride along the frontal boundary that sets up across the region, producing light mountain snowfall and some valley rain showers Monday through Wednesday. Monday looks to be more widespread across the region, while Tuesday and Wednesday see moisture supplies dwindle. This could change too, as models grapple with a pinched off lobe of low pressure Tuesday that digs southward across Baja. Another trough waits on deck out west too. This time, models are digging some cold air south that promises to bring temperatures back down Thursday into the weekend. Additional snow is promised too, as we get a shot of cold air. To be honest, I'm not going to get my hopes up on this one. GFS digs the cold air farther south this time, promising to get the front down into the Four Corners. For now, it looks like the best snow rates are in the Thursday time frame, trailing off Friday afternoon. Overnight lows look to dip below seasonal normals too. Given the expected warm start to the week, and the potentially cold finish, I suspect this will be a roller coaster forecast this week.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Issued at 1033 AM MST Sat Jan 3 2026

Pockets of low stratus and fog have developed around the region. This has lead to LIFR conditions at a few terminals. Conditions will generally improve as we head into the afternoon hours with winds remaining light beneath high pressure today. Guidance suggests more low stratus and fog early Sunday morning, but confidence is low on specific locales at the moment.

GJT WATCHES/WARNINGS/ADVISORIES

CO...Dense Fog Advisory until noon MST today for COZ006. UT...None.