


Area Forecast Discussion
Issued by NWS Flagstaff, AZ
Issued by NWS Flagstaff, AZ
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852 FXUS65 KFGZ 061640 AFDFGZ Area Forecast Discussion National Weather Service Flagstaff AZ 940 AM MST Sun Jul 6 2025 .SYNOPSIS...Warming temperatures and mainly dry conditions are expected this week. There will be a slight chance of showers and thunderstorms each afternoon, mainly over the Mogollon Rim and White Mountains. Temperatures will peak from Tuesday through Thursday, with very hot conditions at the lower elevations. && .DISCUSSION...High pressure stretching from northern Mexico into New Mexico will slowly shift northwestward into Arizona over the next several days. A weak return of moisture allowed for a few showers and thunderstorms on Saturday afternoon in the White Mountains and a stray shower as far west as Heber. This weak moisture push will bring slight chances for a few showers/storms farther west today into early next week, including the Flagstaff area and northern Yavapai County. This is still looking like a low-grade monsoon pattern at best, with no real significant moisture push showing up over the next 7 days. Also, much of the activity will be high-based, producing gusty/erratic winds and generally light rainfall amounts. The main story over the coming week is going to be the building heat as the high pressure system parks over Arizona and strengthens. Ensemble mean forecasts of 500 mb heights are still 596-599dam from Tuesday through at least Thursday and possibly beyond. This translates to highs in the low 90s for the mountains to around 100F for Prescott/Payson/ Winslow, and near 110F for the Verde Valley. The lowest elevations of the Grand Canyon are forecast to reach 110-115F. Extreme Heat Watches have been issued for the Grand Canyon below 4000 feet from Tuesday through Thursday, and for Yavapai and Gila counties below 4000 feet for Wednesday when it looks like the heat peaks. Thursday into the weekend, ensemble means show the strong ridge suppressed slightly southward, which would cut off our meager moisture flow even more. Storm chances drop to less than 10% over the western parts of the Mogollon Rim including Flagstaff, as well as Yavapai County. && .AVIATION...Sunday 06/18Z through Monday 07/18Z...VFR conditions. ISO -SHRA/-TSRA possible before 03Z, mainly over the higher terrain. Winds SW 5-10 kts before 02Z, then becoming VRB. Gusty, erratic outflow winds possible in and around TS. OUTLOOK...Monday 07/18Z through Wednesday 09/18Z...VFR conditions. ISO -SHRA/-TSRA possible over the higher terrain each afternoon. Daytime winds W/SW 10-15 kts on Monday, subsiding to 5-10 kts on Tuesday. Gusty, erratic outflow winds possible in and around TS. && .FIRE WEATHER...Today through Monday...A warming trend will continue, along with mostly dry conditions. Minimum afternoon RH values 10-20%. 20-40% chance of high-based showers/thunderstorms each afternoon, primarily across the Mogollon Rim and White Mountains. Afternoon west-southwest wind 10-20 mph. Gusty/erratic winds possible near showers/storms. Tuesday through Thursday...Hot and mostly dry conditions will continue. 15-35% chance of showers/thunderstorms near the White Mountains each afternoon. Minimum RH values 8-20%. West-northwest winds 5-15 mph on Tuesday, becoming more westerly 10-20 mph on Wednesday and Thursday. && .FGZ WATCHES/WARNINGS/ADVISORIES... Extreme Heat Watch from Tuesday morning through Thursday evening for AZZ006. Extreme Heat Watch from Wednesday morning through Wednesday evening for AZZ018-037. && $$ PUBLIC...JJ AVIATION...Humphreys FIRE WEATHER...JJ For Northern Arizona weather information visit weather.gov/flagstaff