Area Forecast Discussion
Issued by NWS Flagstaff, AZ
Issued by NWS Flagstaff, AZ
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660 FXUS65 KFGZ 190520 AFDFGZ Area Forecast Discussion National Weather Service Flagstaff AZ 1020 PM MST Tue Nov 18 2025 .SYNOPSIS...Cold and wet conditions will dominate the next few days, with more unsettled weather possible over the weekend. Rain looks to be the main precipitation type, but high elevation snow will sneak in by mid-week. && .DISCUSSION...The upper low is centered near southern California this afternoon, with plentiful moisture continuing to push northward into Arizona. Large scale lift and some instability have been maximized along/west of I-17 and especially south central Yavapai County where rainfall totals since late Monday are in the 1.00" to 2.50" range, with moderate rain continuing at this time. As the upper low slowly pushes eastward into western Arizona by Wednesday afternoon, additional disturbances will rotate northward into the western half of the state and bring the threat of additional moderate to locally heavy rainfall. Yavapai County still looks favored for some of the heaviest rain, with additional amounts of 1-2 inches and localized areas of 2+ inches especially over favored upslope regions. For this reason, we have issued a Flood Watch for Yavapai County through Wednesday afternoon. The other aspect to this system will be high elevation snowfall. The latest forecasts keep the snow level near 8000 feet through mid day Wednesday, then values gradually drop as the upper low moves into the area later Wednesday afternoon through Thursday. So by Wednesday evening into especially Thursday morning, there will be a chance of snow down to the 6500-7000 ft level which would include portions of I-40 (Williams to east Flagstaff) and I-17 (Flagstaff to around Munds Park). By this time, much of the heavier precipitation will have moved into eastern Arizona where snow levels will be higher. Our latest forecasts call for some light snow along the Mogollon Rim above about 6500 feet, mostly in the half to 2 inch range and again the most likely timing is Wednesday evening into Thursday morning. Higher parts of the Kaibab Plateau, San Francisco Peaks, and White Mountains will see heavier amounts of 4-8"+ but these are mostly higher than the populated areas. Our current system will be getting moved east out of our area due to an upstream low approaching from the northwest. Much of the model and ensemble data take this low pretty far south, into northern Baja Fri/Sat before ejecting northeastward by Sunday. Thus the more favorable areas for additional precipitation are over southern Arizona, but we`ll have to keep an eye on the late weekend period for a chance of rain/high elevation snow. Current PoPs are 20-40%, favoring I-40 south. && .AVIATION...Wednesday 19/06Z through Thursday 20/06Z...WDSPRD MVFR/IFR through the period due to CIGS/SHRA/SHSN/TSRA/BR. Snow levels ranging from 6500-7500 kft MSL in the heavier or prolonged showers and by late afternoon Wednesday. Worse conditions west of a KPAN-KPGA line, VFR possible at times east of that line, especially northeast of the Mogollon Rim and north of the White Mountains. Sfc winds will not impact flight operations, except near TSRA. OUTLOOK...Thursday 20/06Z through Saturday 22/06Z...Expect WDSPRD MVFR/IFR through late Thursday due to CIGS/SHRA/SHSN/TSRA/BR. Areas of precipitation do spread east during this period, affecting much of the region through Thursday. Improving conditions Thursday night and Friday as VFR develops and showers decrease or end. Sfc winds are not expected to impact flight operations && .FIRE WEATHER...Wednesday through Thursday...Scattered to widespread showers expected Wednesday and Thursday with the snow level lowering to 7500 feet by Wednesday morning and 6500-7000 feet by Thursday morning. Winds S-SW 10-15 mph with gusts as high as 25 mph both days. Friday through Sunday...A chance for isolated to scattered showers continues through the weekend, mainly south of the I-40 corridor. Snow level 7000-8000ft. Winds E-SE 5-10 mph on Friday and Saturday, becoming N 5-10 mph on Sunday. && .FGZ WATCHES/WARNINGS/ADVISORIES... Flood Watch through Wednesday afternoon for AZZ008-037. && $$ PUBLIC...JJ AVIATION...Peterson FIRE WEATHER...Bernhart For Northern Arizona weather information visit weather.gov/flagstaff