


Area Forecast Discussion
Issued by NWS Flagstaff, AZ
Issued by NWS Flagstaff, AZ
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207 FXUS65 KFGZ 071656 AFDFGZ Area Forecast Discussion National Weather Service Flagstaff AZ 956 AM MST Mon Jul 7 2025 .SYNOPSIS...Hot temperatures and mainly dry conditions are expected this week. There will be a slight chance of showers and thunderstorms each afternoon, with most of the activity over the Mogollon Rim and White Mountains. Temperatures will peak from Tuesday through Thursday, with very hot conditions at the lower elevations. && .DISCUSSION...Strong high pressure was centered near southeast Arizona this morning, with a closed low off the central California coast. The resulting southerly flow has allowed for some limited moisture to return to our area, though these values are on the low end for monsoon season. Expecting isolated to scattered high-based convection to develop this afternoon, with the highest coverage over the Mogollon Rim/White Mtns (20-40%) and a few showers or storms possible as far west as Prescott. Storm motion will be toward the northeast, so activity over the Rim/White Mtns will push into the Little Colorado River Valley so places like Winslow, Holbrook, and St Johns also have a 20-30% chance of seeing some light rain but also gusty outflow winds to 40+ mph. On Tuesday, some of this moisture gets into western Coconino County so the focus for isolated storms looks to be Flagstaff westward, including the Prescott area where a 10-25% chance of showers/storms is forecast. However, the main story over the next several days is going to be the building heat wave. The center of high pressure will continue to gradually shift northwestward and be right over central Arizona by Wednesday. It is then forecast to drift south and west by late in the week and weekend, reaching southern California. In addition to bringing heat to our area, the resulting flow as the high shifts south/west will mostly cut off our moisture and lead to a further downturn in storm chances. Extreme Heat Warnings go into effect for the Grand Canyon below 4000 feet today and continue through Thursday, with a good chance this will need to be extended to Friday and possibly beyond. There is also an Extreme Heat Warning for Yavapai and Gila counties below 4000 feet on Wednesday when the heat is forecast to peak. && .AVIATION...Monday 07/18Z through Tuesday 08/18Z...VFR conditions. ISO -SHRA/-TSRA before 03Z, mainly north of a KCMR-KPAN line. Winds SW 10-15 kts before 02Z, then becoming VRB 5-10 kts. Gusty, erratic outflow winds possible in and around TS. OUTLOOK...Tuesday 08/18Z through Thursday 10/18Z...VFR conditions. ISO -SHRA/-TSRA mainly west of a KPGA-KINW-KJTC line each afternoon. Winds W/SW 5-10 kts on Tuesday, becoming W 10-15 kts on Wednesday. Gusty, erratic outflow winds possible in and around TS. && .FIRE WEATHER...Today and Tuesday...Hot and mainly dry conditions. Slight chance of showers and thunderstorms each afternoon, mainly over higher terrain. Winds west/southwest 5-15 mph with gusts up to 20 mph each afternoon with minimum afternoon RH 10-20%. Gusty erratic outflow winds possible near thunderstorms. Wednesday through Friday...Hot and mainly dry conditions continue, outside of a slight chance of showers and thunderstorms mainly near the White Mountains each afternoon. West winds 5-15 mph Wednesday, then west/southwest 10-15 mph with gusts 20-30 mph Thursday and Friday. Minimum afternoon RH 8-20%. && .FGZ WATCHES/WARNINGS/ADVISORIES... Extreme Heat Warning from 10 AM this morning to 8 PM MST Thursday for AZZ006. Extreme Heat Warning from 10 AM to 8 PM MST Wednesday for AZZ018- 037. && $$ PUBLIC...JJ AVIATION...Humphreys FIRE WEATHER...JJ For Northern Arizona weather information visit weather.gov/flagstaff