415 FXUS65 KFGZ 261100 AFDFGZ Area Forecast Discussion National Weather Service Flagstaff AZ 400 AM MST Thu Jun 26 2025 .SYNOPSIS...Warming temperatures and mainly dry conditions continue through the weekend, outside of light afternoon showers around the White Mountains. More widespread shower and thunderstorm activity looks to set in by the middle of next week. && .DISCUSSION...Today...The trough that has been situated to the west begins to lift and weaken today. Southwesterly flow looks to usher in drier air across much of the area, outside of some lingering moisture across the White Mountains. Thus, dry and warmer conditions are expected again today, with only a slight chance for high-based showers and possibly a thunderstorm around the White Mountains this afternoon. Friday through Monday...Heights begin to rise for the end of the week and into next week as high pressure starts to build over the southwest. Temperatures look to begin to rise over the weekend and into early next week, ushering in a return of more seasonable to slight above normal temperatures. Some heat headlines may be needed for the lower elevations of the Grand Canyon over the weekend as highs look to exceed 110F by Sunday. Dry conditions look to prevail each day as well, with mainly only a slight chance for high-based showers over the White Mountains each afternoon. A bit more activity could be possible during the afternoon Monday, depending on how much moisture is able to be advected northward at this point. Tuesday onward...Another weak trough looks to setup just off the California coast near the start of next week. While at the same time, a potential tropical system passes just off the tip of the Baja California peninsula, potentially driving a surge of moisture northward along the Gulf of California. With the increased southerly flow over Arizona, this plume of sub-tropical moisture is expected to be advected northward into Arizona. Thus, daily chances for showers and thunderstorms are expected over much of the higher terrain starting as early as Tuesday and continuing through the rest of the week. The onset of the monsoon appears to be upon us! && .AVIATION...Thursday 26/12Z through Friday 27/12Z...VFR conditions. ISO -SHRA/-TSRA in vicinity of KJTC, from 20Z to 03Z. Gusty winds possible in and around TS. Winds SW 10-15 kts with gusts to 20 kts after 17Z and before 03Z, otherwise VRB < 5 kts. OUTLOOK...Friday 27/12Z through Sunday 29/12Z...VFR conditions. Winds W/SW 8-14 kts with gusts 15-20 kts each day, becoming VRB <5 kts overnight. && .FIRE WEATHER...Today and Friday...Mainly dry and warm conditions, outside of a slight chance for high-based showers and thunderstorms near the White Mountains each afternoon. Winds southwest 5-15 mph with gusts to around 20 mph each afternoon. Gusty, erratic winds possible in and around thunderstorms. Saturday through Monday...Warmer and mainly dry conditions. Wind west/southwest winds 5-15 mph and afternoon minimum RH values 5-15% each day. && .FGZ WATCHES/WARNINGS/ADVISORIES...None. && $$ PUBLIC...Humphreys AVIATION...Humphreys FIRE WEATHER...Humphreys For Northern Arizona weather information visit weather.gov/flagstaff