Area Forecast Discussion
Issued by NWS Tucson, AZ
Issued by NWS Tucson, AZ
819 FXUS65 KTWC 220914 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 214 AM MST Sat Nov 22 2025 .SYNOPSIS...An active pattern continues through this weekend as another weather system arrives late today through Sunday bringing rain and cooler temps. Precip chances begin in western Pima County this afternoon expanding to cover all of southeast Arizona this evening through the overnight hours. Sunday precipitation chances decrease from west to east. High temps cool to below normal Sunday and Monday, then begin a warming trend through the end of the week. && .DISCUSSION...A closed low is centered off the northern coast of Baja with moisture streaming into Arizona out ahead of it. The low will slowly move onshore today passing through Arizona tonight into Sunday morning. Shower activity is currently ongoing over southern California and will spread eastward in to Arizona as the low moves onshore. Ahead of the precip winds will be breezy with gusts 25-35 mph from Tucson eastward. Hi-res guidance shows precipitation moving into far western Pima County between noon and 1 PM MST, reaching Tucson around 5 PM, then encompassing all of southeast Arizona during the evening and overnight hours. Initially the precipitation will be all rain with isolated embedded thunderstorms possible during the evening and overnight hours. As the core of the low moves through Arizona Saturday night snow levels drop to around 7500-8000 feet. Isolated to scattered activity continues Sunday morning then dissipates from west to east in the afternoon. Rainfall totals in the valleys are expected to be 0.15"-0.75" with the highest totals likely in Pinal County and the northern half of Graham County, which will see the best synoptic scale lift on the low`s current trajectory. Up to an inch of liquid will be possible in the mountains. With the initial warm air mass snow totals will be on the lighter side generally 1"-2" in the Catalinas and 2"-6" in the Pinaleno and White Mountains above 7500-8000 feet. The bulk of the precip is expected to fall this evening and during the overnight hours. Flash flooding is not expected but area washes and drainages will be running. By Sunday evening rain chances will be below 10 percent as the low moves into Colorado. Temperatures today will be around normal cooling to 5-10 degrees below normal Sunday into Monday. Freezing temperatures likely return for areas south and east of Tucson each morning Monday into the middle of next week. In the wake of the low ridging builds in which will lead to a warmup after Monday. High temperatures warm to just below normal Tuesday then a few degrees above normal through the end of the week. Next weekend into early next week ensembles show another Pacific trough potentially moving through, which could bring another round of precipitation and cooler temperatures. && .AVIATION...Valid through 23/12Z. SCT to BKN clouds AOA 12k ft AGL after 22/14Z. After 22/21Z clouds become BKN 4k-8k ft AGL through the end of the period. Scattered -SHRA will be possible at KTUS and KOLS starting around 22/23Z expanding to KDUG by 23/03Z. Isolated embedded thunderstorms will be possible during the evening and overnight hours. SFC winds will generally be from the southeast at 5-10 kts through 22/16Z increasing to 10-15 kts gusting 20-25 kts at KTUS, KSAD, and KDUG and up to 30 kts at KOLS through 23/02Z. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...A weather system will be moving through today and Sunday bringing precipitation and breezy winds. Rain chances begin this afternoon into the overnight hours with the bulk of any rainfall occuring this evening and overnight. Embedded thunderstorms will be possible. Light mountain snow will also be possible tonight above 7500 feet. Shower activity decreases from west to east on Sunday. Late this morning into the early evening 20 foot winds will be out of the south southeast 12-18 mph with gusts up to 30 mph mainly south and east of Tucson. The low will usher in below normal temps Sunday and Monday, then a warming trend takes over. Min RH will be 30-60 percent through Tuesday, dropping to 20-30 percent thereafter. && .TWC WATCHES/WARNINGS/ADVISORIES... None. && $$ Hardin Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson