textproduct: Grand Junction

KEY MESSAGES

- Several rivers across SW Colorado are forecast to crest overnight Sunday into Monday.

- The San Juan River at Pagosa Springs is forecast to reach major flood stage which has prompted the continuation of the Particularly Dangerous Situation Flood Warning for that area.

- A cold frontal passage will occur overnight Sunday into Monday, driving mountain snowfall at and above pass level. Morning commutes could be slick and slushy.

- Widespread precipitation chances diminish Monday morning, with drier conditions expected Tuesday.

DISCUSSION

Issued at 927 PM MST Sun Nov 1 2026

SUNDAY INTO MONDAY:

A cold front pushing across eastern Utah and western Colorado tonight will usher in a cooler air mass, holding temperatures below the seasonal averages to kick off the workweek.

Widespread precipitation will continue across the region overnight before tapering off from southwest to northeast Monday afternoon and evening. An additional 0.5-1" of rainfall remains possible across the higher terrain of the San Juans and adjacent valley basin through early Monday. With snow levels dropping behind the front, snow across the high passes will lead to slick and slushy travel during the Monday morning commute. In the northern Divide mountains, ensemble and deterministic guidance consistently depict 4 to 8 inches of accumulation above 9000 ft. through Monday evening; consequently, the Winter Weather Advisory has been expanded northward to account for these localized travel impacts.

Hydrologic impacts will peak during the overnight hours into Monday morning as area rivers approach crest levels. While precipitation chances diminish late Monday, rivers will remain near or above bankfull well after the rain ceases. Please refer to the hydrology section below for specific river stage and crest forecast information.

THE REST OF THE WEEK:

Drier conditions return Tuesday and temperatures will also continue to hover below normal for the better half of the work week. A quick moving clipper system has the potential to bring some light showers to the region mid to late next week, although models don't have the best grasp on this as of yet, so details remain vague.

AVIATION /06Z TAFS THROUGH 06Z TUESDAY/

Issued at 1017 PM MST Sun Nov 1 2026

Rain and showers continue overnight though breaks in precip are expected. MVFR/IFR conditions will be the rule due to low ceilings and vis under the heavier showers. Many TEMPO and PROB30 groups continue for TAF sites to account for this. ILS breakpoints will also continue to be met for most TAF sites through tonight and into much of tomorrow. Rain has already started changing to snow at higher elevations so KTEX may see some flakes.

HYDROLOGY

Issued at 927 PM MST Sun Nov 1 2026

Deep atmospheric moisture associated with the ongoing atmospheric river will begin to taper from southwest to northeast Monday morning. However, substantial hydrologic concerns will persist well after precipitation rates diminish.

Widespread, excessive runoff over already saturated terrain will drive rapid rises across drainage networks, with several rivers throughout southwest Colorado forecast to crest overnight Sunday into Monday. The primary point of concern remains the San Juan River at Pagosa Springs, where guidance continues to indicate a potentially historic crest. Given the high confidence in widespread inundation and severe impacts, this remains a Particularly Dangerous Situation (PDS).

Multiple other basins across the region will likely experience moderate to major flood stages as runoff routes through the system. Because peak crests are projected to occur during the overnight hours, exercise extreme caution as water across roadways is difficult, if not impossible, to detect at night. The Flood Watch remains in effect through Monday morning to account for both flood risks and ongoing river flooding.

GJT WATCHES/WARNINGS/ADVISORIES

CO...Winter Weather Advisory from 3 AM Monday to midnight MST Monday night for COZ004. Winter Weather Advisory until 6 PM MST Monday for COZ009-010- 012-013. Winter Storm Warning until noon MST Monday for COZ018-019. Flood Watch through Monday morning for COZ019-021>023. UT...Flood Watch through Monday morning for UTZ022-028-029.