textproduct: Grand Junction

KEY MESSAGES

- Freeze Warnings in place for the Yampa Basin and Central Colorado Basin Tuesday night and Wednesday morning.

- Isolated showers and thunderstorms continue across the mountains Wednesday, with some snow mixed in 8000 feet and above.

- Another disturbance works across the region Thursday and Friday with measurable mountain snow and rain making it to valley floors.

DISCUSSION

Issued at 1052 PM MDT Tue Apr 28 2026

Satellite imagery shows the 18Z models are tracking well with the current weather pattern with low pressure over central Canada and off the Southern California Coast, and ridging off the Pacific Northwest extending to the north up over British Columbia. The 00Z sounding shows the atmosphere has dried significantly in the zonal flow and the subsidence inversion continues to cap the region below about 550mb. Hence, we only saw scattered light showers through the northern and central mountains today. Tomorrow is promising to be a bit more active across the northern and central Colorado mountains as a shortwave in the Great Basin ejects to the east across eastern Utah and Western Colorado through the late morning and afternoon to push the inversion out, and provide cool air aloft and better convective dynamics. Look for isolated showers initiating in the late morning over the mountains with diurnal heating, becoming more scattered with embedded isolated thunderstorms mostly along and north of the I-70 corridor through the afternoon. With the drier atmosphere, little accumulation is likely, but small pea-sized hail is possible with the stronger showers and thunderstorms. This activity will quiet through the evening and overnight into Thursday.

The low off the SoCal Coast will make a turn to the east tomorrow afternoon making landfall by Thursday morning as another stronger shortwave drops into the Great basin and ejects east over the region. This will be the next real chance for moisture across the region, but it will be much less than the last system. As the low tracks inland along the US-Mexico Border, it will pull some moisture up into the southern mountains Thursday and Friday as it passes to the south. Look for isolated to widely scattered showers through the day Thursday across the region mostly over the higher terrain with a few thunderstorms through the afternoon. Coverage of storms will be higher to the east over the mountains, especially along the Divide. Snow levels will be around 8000 feet across the north to 9000 feet down south Thursday, falling to 7000 and 8000 feet respectively overnight into Friday. By Thursday evening, showers will be ending across the northern areas with the activity becoming focused to the south on the San Juan Mountains. There is a chance for some snow accumulation on the passes in the San Juans, but for this late storm, winter headline are not likely. Expect the heaviest snow Friday morning with showers tapering off through the afternoon. You will still want to stay alert to the forecast and for possible winter driving conditions if you'll be driving in the southern mountains Friday.

Expect light scattered showers to continue Saturday over the southern mountains, ending Sunday as high pressure moves in over the region. Temperatures will warm to five to ten degrees above normal Sunday and Monday under the high pressure, but another system is looking to move through mid next week to cool things down again. The initial look at this next system is on the drier side, but it's way to soon to tell. Stay tuned to see how it turns out.

AVIATION /06Z TAFS THROUGH 06Z THURSDAY/

Issued at 1130 PM MDT Tue Apr 28 2026

VFR conditions and light winds overnight dominate the TAF forecast. Instability on Wednesday with a passing wave will lead to shower activity over the Colorado high country with KASE and KEGE the most likely areas to see a passing shower or possible thunderstorm. Gusty winds in excess of 35 mph will be the main threat near showers and storms.

GJT WATCHES/WARNINGS/ADVISORIES

CO...Freeze Warning until 9 AM MDT Wednesday for COZ001-002-008. UT...None.