Area Forecast Discussion
Issued by NWS Grand Junction, CO
Issued by NWS Grand Junction, CO
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266 FXUS65 KGJT 240422 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 1022 PM MDT Sun Aug 23 2026 .KEY MESSAGES... - This week will see daily afternoon thunderstorm chances, particularly along the higher terrain of western Colorado and eastern Utah. - Localized heavy rainfall continues to pose a threat to flash flooding over burn scars and susceptible terrain. - Daytime highs will run ~5 degrees above normal to start the week. && .DISCUSSION... Issued at 1014 PM MDT Sun Aug 23 2026 THIS WEEK: The current synoptic level setup continues to be dominated by high pressure over the west. Beginning on Monday, moisture and PWAT anomalies begin to take a downturn compared to previous days. This will mean less widespread precipitation chances for the area. However, there remains enough moisture to cause daily afternoon thunderstorm chances over the higher terrain. Orographic lift will also be a contributing factor to help enhance these mountain storm chances. Additionally, morning cloud cover has the ability to dictate where storm activity materializes as daytime heating can affect the evolution of storms. As a result of all of this, localized heavy rainfall is possible from these storms which inherently poses a threat of flash flooding, especially around burn scars and susceptible terrain. By midweek, the high gradually shifts back towards the Desert Southwest. Because of the continuous presence of moisture, each afternoon`s storm chances may look similar to each other. That is, isolated to scattered and mostly confined to the higher terrain. Synoptic forcing will be somewhat weak for this period, with the occasional shortwave interrupting the flow around the high, which will provide some additional lift. So long as the surface levels remain saturated in certain places, flash flooding will remain a concern, particularly for burn scars and susceptible terrain. Primary threats with these storms continue to be localized heavy rainfall, lightning, and gusty outflows. Daytime highs will start off ~5 degrees above normal to start the week, with a slight uptick to ~5-10 degrees above normal by late week. By the weekend, temperatures begin to gradually decrease each day. && .AVIATION /00Z TAFS THROUGH 00Z TUESDAY/... Issued at 529 PM MDT Sun Aug 23 2026 Scattered showers and thunderstorms continue to be around for some terminals, but storm activity will gradually diminish after sunset. Winds around storms could get gusty as well as the additional wind threat from nearby outflows. Winds will resume terrain driven patterns overnight. Cloud cover will likely linger into the morning hours as we have been seeing the past few days. Shower and storm chances return Monday afternoon, particularly for the high terrain terminals. All that being said, VFR conditions will prevail. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && $$ DISCUSSION...BS AVIATION...TGJT