textproduct: Grand Junction

KEY MESSAGES

- A winter system impacting the northern Colorado mountains will continue through this afternoon. A Winter Weather Advisory is in effect for the Elkhead and Park Mountains until 5 PM. - Another system arrives tonight with more widespread accumulations and stronger winds at the high elevations. Winter Storm Warnings are in effect for portions of the northern and central Colorado mountains Friday evening through Saturday evening.

- Unsettled weather continues through the coming work week in the northern Colorado mountains with mostly periods of light snow showers. Elsewhere across the region, look for a general warming trend, but the snow covered mountains valleys will see cold inversions set up overnight lasting through the days.

SHORT TERM /THROUGH SATURDAY/

Issued at 309 AM MST Fri Dec 5 2025

Models are in good agreement with satellite imagery with the high centered about 500 miles off the Northern California Coast, a low circulation off Baja, and deep troughing over the Plains States. This pattern gives eastern Utah and Western Colorado a straight shot of systems out of the Gulf of Alaska descending through the Pacific Northwest into the region keeping unsettled weather in the forecast. The midlevel pressure gradients remain strong supporting stronger orographic lift for the next few days. The left exit region of the jet passes over the northern areas today, but it coincides with a dry slot to limit showers this afternoon. Look for snow showers to continue along and north of the I-70 corridor today with the heavier snow showers through the morning hours as the shortwave passes, and tapering off through the afternoon as the drier air moves in. Kept the Winter Weather Advisory in place through 5 PM for the Elkhead and Park mountains through today for generally four to eight inches snow with locally higher amounts possible in favored terrain.

Another surge of deeper moisture moves into the region overnight tonight with the start of the next, much stronger winter storm. Look for snow showers to pick up through the evening over the Park Range, and spreading west into the Elkhead Mountains and south across the Flat Tops to Grand Mesa and the Elk and West Elk Mountains overnight. THe heaviest snow will fall through the overnight into Saturday afternoon with showers tapering off through the late afternoon and evening. QPF increased significantly in the latest package; tempered it by blending it with the last run. Also went with WPC snow ratios through these two storms as the NBM's were ridiculously high. Even still, two to three feet of new snow is possible on the northwestern face of the Park Range at higher elevations. Kept the current Winter Storm Warnings in place for Zones 4, 13, 10 and 12 with Winter Weather Advisories for Zones 5 and 8, and Zone 9 above 8,000 feet. Expect hazardous winter driving conditions on the roads and passes across the northern and central Colorado mountains through Sunday morning.

LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/

Issued at 309 AM MST Fri Dec 5 2025

The high IVT airmass will be flushing eastward as we move into Saturday night on the back part of this second storm. Even though QPF amounts look to be waning colder air moving aloft... with a dip in the jet aloft...will boost the snow-2-liquid ratios and northerly orographics will continue to add to snow totals. The bulk of the heaviest snow should be done by sunrise on Sunday but a moist dendritic layer remains over the northern and central divide mountains through early afternoon. Warm air advection kicks in through the afternoon as the jet shifts onto the Plains and this stabilized the column and most showers should be ending by sunset. The upcoming week looks to be milder as we flush the colder air out. The downstream edge of the strong blocking high over the EPac will slowly ooze inland and this will help keep the colder air well to our north where the main storm track will be. That is not to say we remain dry as our northern high mountains will remain on the edge of the mositure plume and we will see off and on snow chances through the week. For the most part these will be just be glancing blows and the snow amounts remain light with each one. Totaled up however we could see another foot of snow over the high peaks of the Park Range through Thursday. Temperatures look to slowly warm through the week and be some 10 to 15 degrees above normal from mid- week onwards. This is likely to be hampered in some of the valleys where the residual snow pack is deeper. This will also keep a mixture of rain and snow in the forecast in the valleys adjacent to the northern and central mountains.

AVIATION /12Z TAFS THROUGH 12Z SATURDAY/

Issued at 430 AM MST Fri Dec 5 2025

Low to mid clouds and light snow showers below ILS breakpoints generally along and north of I-70 will impact KHDN, KRIL, KEGE and KASE through about 21Z before improving. KDRO will see low stratus through about 10Z before the clouds burn off. Otherwise look for mid to high clouds across the region with light winds. The next storm system moves in from the north MVFR to LIFR conditions below ILS breakpoints impacting KHDN after 03Z, KASE, KEGE and KRIL after 06Z and KGUC after 09Z.

GJT WATCHES/WARNINGS/ADVISORIES

CO...Winter Weather Advisory until 5 PM MST this afternoon for COZ004. Winter Storm Warning from 5 PM this afternoon to 11 PM MST Saturday for COZ004-013. Winter Weather Advisory from 5 PM this afternoon to 11 PM MST Saturday for COZ005. Winter Weather Advisory from 11 PM this evening to 11 PM MST Saturday for COZ008-009. Winter Storm Warning from 11 PM this evening to 11 PM MST Saturday for COZ010-012. UT...None.