


Area Forecast Discussion
Issued by NWS Grand Junction, CO
Issued by NWS Grand Junction, CO
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087 FXUS65 KGJT 182343 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 543 PM MDT Fri Jul 18 2025 .KEY MESSAGES... - Showers and thunderstorms continue Saturday around the region. - Flash flooding remains a threat for burn scars and flood prone areas. - Mountain showers and thunderstorms remain in the forecast into next week. - Smoke will continue to ebb and flow around the forecast area along with wildfire activity. && .SHORT TERM /THROUGH SATURDAY NIGHT/... Issued at 307 PM MDT Fri Jul 18 2025 A recognizable summer regime has taken up residence here on the West Slope. Subtropical moisture continues to work north across the Four Corners along the western perimeter of broad high pressure anchored over the southern CONUS. A training line of convection has formed along a Monticello, UT to Grand Junction heading. Terrain enhancements by the Abajos and La Sals in concert with tropical moisture has kept this line a hotbed of convection this afternoon. Elsewhere, showers have been less impressive. Shower activity will continue on the terrain into early evening then decay quickly towards sunset. The upper level regime holds on Saturday. The progressive, zonal pattern to our north drags a shortwave through Saturday afternoon. This is expected to keep shower chances for pretty much everywhere north of the Colorado River/I-70 corridor, while south of there, terrain based convection will produce additional showers and thunderstorms. Ensemble guidance has picked up on some dry slotting in southeast Utah and southwest Colorado, leading to some inconsistency with precipitation chances there. Ensembles also drop PWAT`s Saturday. While showers may not have the punch they had today, there should still be ample fuel for mountain showers and thunderstorms with PWAT`s around 0.60" across the region. This should continue to help with wildfire smoke, as the Deer Creek, Turner Gulch, and South Rim Fires received rainfall within their perimeters this afternoon. Temperatures will trend near to a few degrees below normal, given the cloud cover. Once again, shower activity will taper off near sunset Saturday evening. && .LONG TERM /SUNDAY THROUGH FRIDAY/... Issued at 307 PM MDT Fri Jul 18 2025 On Sunday dry air will still be in place, which should limit afternoon convection. Although the high terrain can expect isolated to scattered showers and storms. Highs come up a few degrees in the drier air. On Monday there are signs that moisture surges back in from the south as heights increase due to a PacNW trough. This should result in another uptick in showers and storms around the area into Tuesday. The uncertainty is how that PacNW trough evolves, because as it ejects and breaks apart flow over us will change. With dry air not far to our west it will only take an slight shift to west northwest to advect that air into the area. Ensembles are showing that eventually the dry air filters in later this week. && .AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 543 PM MDT Fri Jul 18 2025 Showers and thunderstorms have dissipated for the most part over the region, though KHDN, KMTJ, and KVEL may see occasional rainfall over the next couple hours. Cigs may drop below ILS breakpoints at some higher elevation terminals into the evening though, particularly at KASE and KEGE. Tomorrow, storms return, impacting mostly the high terrain. Gusty afternoon winds upwards of 25 mph are possible across portions of the region, with stronger gusts expected near thunderstorms. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && $$ SHORT TERM...LTB LONG TERM...KJS AVIATION...TGJT