textproduct: NWS Flagstaff

SYNOPSIS

Expect temperatures 5-10 degrees above average through the rest of the week. Thunderstorm coverage will increase through Friday as additional monsoon moisture is drawn across the state. A bit cooler temperatures and slightly lower storm coverage is forecast for the weekend.

DISCUSSION

Hot temperatures under a high pressure feature will peak today with some locations approaching record highs. An Extreme Heat Warning is in effect for areas below 4,000 feet in the Grand Canyon through Thursday night, so use caution if you hike below the Grand Canyon Rim. Limited monsoon moisture returns today with scattered activity though this afternoon and early evening staying mostly along the Mogollon Rim and White Mountains. There remains a slight chance for these storms to move into the lower elevations of Gila and Yavapai County by this evening.

As the second half of the week progresses the high pressure area shifts further to the east which will bring in more monsoon moisture across the state. Look for POPs to rise and coverage to increase Thursday into the weekend with most of the area seeing a chance for thunderstorms. Temperatures Thursday will be slightly cooler but close to Wednesday's highs, but as moisture and clouds increase, temperatures trend downward each day and get close to normal or just above normal by the weekend. As storm coverage increases and soils once again become wet, flash flood concerns will be on the rise late this week and into the weekend.

AVIATION...Thursday 20/06Z through Friday 21/06Z

Primarily VFR conditions. ISOLD-SCT SHRA/TSRA along/south of a KPRC-KRQE line through 07Z-09Z. Stronger storms may bring brief MVFR/IFR conditions. Storm activity increases again after 18Z Thursday and continues well into the evening. Highest coverage Thursday along/south of a KGCN-KFLG-KSJN line, with isolated storms farther north. Winds SW-NW 5-15kts daytime, light and variable or terrain driven overnight. Gusty and erratic winds near storms.

OUTLOOK...Friday 21/06Z through Sunday 23/06Z...Primarily VFR conditions. SCT-NMRS SHRA/TSRA each afternoon and evening, with the highest coverage on Friday. Stronger storms may bring brief MVFR/IFR conditions. Winds W-NW 5-15kts each day, light and variable or terrain driven overnight. Gusty and erratic winds near storms.

FIRE WEATHER...Thursday and Friday

Scattered to numerous showers and thunderstorms each day with the best coverage on Friday. The primary hazards are lightning, gusty and erratic winds, and brief heavy rain. Outside of storms expect seasonably warm temperatures. Winds are variable at 5-15 mph on Thursday, becoming southwest through west on Friday.

Saturday through Monday...Near to slightly above normal temperatures. Scattered to numerous showers and thunderstorm coverage each afternoon through late evening. Winds southwest through west at 5-15 mph each day, though gusty and erratic winds possible near storms.

FGZ WATCHES/WARNINGS/ADVISORIES

Extreme Heat Warning until 8 PM MST Thursday for AZZ006.