


Area Forecast Discussion
Issued by NWS Grand Junction, CO
Issued by NWS Grand Junction, CO
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616 FXUS65 KGJT 272021 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 221 PM MDT Wed Aug 27 2025 .KEY MESSAGES... - Scattered showers and thunderstorms continue today with most activity done by late evening. - The potential for flash flooding continues today, especially for burn scars and flood prone locales with saturated soils from recent rains. - Temperatures will remain below seasonal climatology. - A drier pattern begins to emerge Thursday and beyond. && .SHORT TERM /THROUGH THURSDAY NIGHT/... Issued at 1248 PM MDT Wed Aug 27 2025 High pressure is currently centered over far northern Mexico, leaving us under west-southwest flow aloft and a push of moisture from a few days ago, but drier air and weak lapse rates in the midlevels are starting to filter in overhead as evident in our latest sounding. This ultimately will result in less instability and perhaps inhibit deep convection today. Although there is still enough instability and moisture for scattered showers and storms regardless. Any storms able to break through the inversion could become strong with hail and gusty winds along with heavy rain. Moisture in the low levels is rather abundant, which may lead to heavy rainfall without lightning even over the valleys. With all of this being said pockets of localized flash flooding are possible, especially over the recent burn scars and the more saturated susceptible locations. Most of the shower activity should dissipate around sunset with isolated showers overnight. Far from the high pressure means temperatures closer to normal today and tomorrow. The models show that the dry air aloft and lapse rates problem will linger tomorrow. So expect that convection will have issues becoming deep much like today. In fact, there might not be less instability across southern portions of the forecast area linger tomorrow so the chances for showers have decreased in that area. Northern portions may see afternoon convection much like today. The potential for heavy rain slightly decreases compared to today. Highs come up a few degrees since most locations should see a bit more sunshine and dry up the low levels a bit. && .LONG TERM /FRIDAY THROUGH TUESDAY/... Issued at 1248 PM MDT Wed Aug 27 2025 The building of high pressure centered to our south will be the catalyst of a shift back to drier weather, at least over the weekend. As this high pressure builds, flow will gradually shift from moist and southwesterly to drier and west to northwesterly. On Friday one last push of moisture will come through before anomalously dry air returns over the weekend. This push of moisture is expected to bring widespread showers and thunderstorms to the region Friday afternoon, especially as the remnants of a closed low off of California`s coast pass through our region as a weak wave on Friday morning and afternoon. On Saturday lingering moisture may be sufficient for terrain based convection. However, by Sunday dry air looks to limit PoPs in all but the southern mountains. Monday and Tuesday look less clear in terms of afternoon convection due to ensemble differences on moisture advection. With the building high pressure and decrease in moisture, high temperatures will begin to climb back towards near normal this weekend. && .AVIATION /18Z TAFS THROUGH 18Z THURSDAY/... Issued at 1144 AM MDT Wed Aug 27 2025 Isolated to scattered showers are ongoing across the region. Through the evening showers and thunderstorms are possible at all TAF sites. The main concerns will be heavy rain, small hail, lightning, and some gusty outflow winds near thunderstorms. Brief drops to MVFR conditions or ILS breakpoints are possible. Convective activity should diminish in the evening. Low ceilings may hang around some TAF sites into the overnight hours. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && $$ SHORT TERM...KJS LONG TERM...GF AVIATION...TGJT