Area Forecast Discussion

KEY MESSAGES

- Precipitation will form across the mountains and foothills along and south of I-70 for this afternoon through early Thursday morning.

- Snowfall amounts of 3-10" with isolated higher amounts possible. - The highest snowfall amounts and worst road conditions are expected for western Park County, possibly extending into northern Park County.

- Pleasant temperatures and dry conditions are expected Thursday through early next week.

DISCUSSION /Through Tuesday/

Issued at 1123 PM MST Tue Nov 3 2026

We are expecting a quiet overnight with mostly clear skies. Skies will be partly cloudy in the morning with increasing clouds by Wednesday afternoon for the high country, Denver metro, and the adjacent plains. Temperatures will top out in the mid to upper 50s for the plains once again. The trough and associated low are currently over Nevada. As this feature moves east, it will bring us the 2nd storm system of the week, which will quickly move through our area on Wednesday afternoon and into Wednesday night. We expect the highest impacts for the central and southern high country.

Precipitation will increase from west to east starting mid afternoon on Wednesday in the high country. The precipitation shield should shift south and east through Wednesday evening and into the overnight. On Wednesday evening, scattered rain showers and perhaps a few snowflakes mixing in are possible for the Palmer Divide. There is a low but nonzero chance (~10-15%) that this potential could even extend into far southern and western parts of the Denver metro. No snow accumulation is expected in these locations. Some rain showers are possible for southern Lincoln County late Wednesday night into early Thursday morning as the low pushes off to the east of our area.

High resolution model guidance has shown an uptick in moisture compared to model runs over the last 24-36 hours. As the afternoon progresses on Wednesday, there should be some modest instability present in the southern high country along with increasing lapse rates. Snow levels are trending lower as well. Snow levels should start around 9,000 feet early Wednesday afternoon. They are now forecast to drop down to 7,500-8,000 feet on Wednesday evening. Snow levels should drop even lower to 6,500-7,000 feet just as the system starts to exit the area early Thursday AM. The track of the low across our southwestern counties or just to the south would bring northeast to east winds at the surface. This flow could extend up in the atmosphere a few kilometers. In this type of flow, Park County looks favored for some upslope flow/enhancement. In particular, the southern Front Range foothills, the Mosquito Range, the Highway 285 corridor, and most of Park County look favored for the heaviest snowfall totals from this system.

Altogether, most short-term models have trended up with snowfall totals and QPF in the last 24-36 hours. QPF amounts of 0.25-0.75" should be common in Park County and adjacent locations with isolated higher amounts possible at the highest elevations. DESI probabilities are honing in on the Mosquito Range/western Park County where there is a 50-60% chance that these locations receive 6 inches or more of snowfall. Thus, we have issued a Winter Weather Advisory for the mountains of Summit County, Park County, the Mosquito Range, Indian Peaks, and South Park. It runs from 2pm Wednesday to 2am Thursday. Most of Park County should get 3+ inches snowfall with the Mosquito Range forecast to receive 5-10 inches of snowfall with localized higher amounts possible. Areas along and adjacent to the I-70 corridor above 7,500 feet, including the northern Gore Range, are forecast to get 3-6 inches of snowfall with areas to the north getting much less.

There is still good agreement that ridging aloft moves back in for Thursday followed by a trough passing to our north on Friday. This system will lack moisture for our area. As a result, there are only low precipitation chances for Friday afternoon in the high country. Temperatures are forecast to reach the mid to upper 50s for the plains on Thursday and Friday. Ridging resumes once again for the weekend and into next week. We expect dry conditions across our area from Saturday through the end of the forecast period. The ridge is expected to strengthen and the center should move closer to us for the end of the weekend and into early next week. Mid 60s look increasingly likely for Denver for Sunday and Monday according to ensemble guidance. This would be 5-10 degrees above average for this time of year. Temperatures on the eastern plains could even be pushing 70 F. For Tuesday, more zonal flow could be in place dropping high temperatures back into the low 60s for most of the plains.

AVIATION /12Z TAFS through 12Z Thursday/

Issued at 400 AM MST Wed Nov 4 2026

Winds were light drainage early this morning and will become light and variable by 15z. By 18z winds will go light easterly and then more ENE by 23z. By 04z this eveing winds will be NE and then may shift to more NNW by 07z. By 10z winds will go to light drainage.

There will be an increase in mid clouds later this morning thru the aftn but VFR conditions will remain in place. There will be a 10-20% percent chc of -shra at APA in the 23z-03z time period with ceilings possibly dropping to 6000 ft. At BJC and DIA ceilings are expected to stay at or above 10000 ft.

BOU WATCHES / WARNINGS / ADVISORIES

Winter Weather Advisory from 2 PM this afternoon to 2 AM MST Thursday for COZ034-037.