Forecast Discussion
409 FXUS65 KTWC 032104 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 204 PM MST Thu Apr 3 2025 .SYNOPSIS...Expect cooler than normal temperatures into the weekend with a slight chance for rain this evening for parts of Pima, Pinal, and Santa Cruz Counties. Chances will be better tomorrow with light valley rain and mountain snow during the afternoon and evening continuing east of Tucson Saturday. Next week a strong ridge of high pressure will move into the area. This will bring a significant warm-up in afternoon temperatures begining late this weekend and persisting through next week. && .DISCUSSION...Longwave troughing will be in place over the next couple of days with a strong ridge centered just off the West Coast. This trough will keep temperatures 10-15 degrees below normal today and Friday and also bring a chance for precipitation this evening into Friday. This evening rain chances are on the lighter side with the 03/12Z HREF just showing weak isolated showers over portions of Pinal, Pima, and Santa Cruz Counties. Radar already shows a few light echos over the Tohono O`Odham Nation and Pinal County. Chances for showers and coverage increases Friday morning into the afternoon as the core of the low moves through. PoPs are generally 30-60 percent with the best chances south and east of Tucson and in the White Mountains. However moisture values are only around normal or slightly below normal. Because of this QPF is low, generally less than 0.1" in the valleys and up to 0.25" in the mountains through Friday night. Saturday rain chances linger mainly east of Tucson with the best chances in the White Mountains. Snow levels will be around 5500 feet with meaningful accumulation only expected above 7000 feet. Snow totals Friday into Saturday in the Sky Islands will be light, generally up to an inch, and 2"-5" in the White Mountains. This weekend the ridge moves onshore and pushes the low east out of the region. This will lead to dry conditions after Saturday and a quick warmup. Highs this weekend will be 5-10 degrees below normal, warming to around normal Monday, then 7-12 degrees above normal by the middle of next week. Beyond Wednesday the Tucson airport will be flirting with 100 degrees with the best chances looking to be Friday. Current NBM probabilities for 100 degrees are around 40 percent for Friday. && .AVIATION...Valid through 05/00Z. Expect SCT-BKN clouds between 6k-10k ft AGL through much of the valid period. Isold -SHRA developing this afternoon into the evening over portions of Pima, Pinal, and Santa Cruz Counties. Friday morning into the afternoon -SHRA activity expands to cover most of southeast Arizona, but impact to TAF sites will be minimal. Sfc winds will be out of the southwest 8-14 kts gusting to 20 kts through 04/02Z becoming variable overnight. Winds increase again Friday afternoon out of the northwest 8-12 kts. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...A weather system will slowly move across the state through Saturday, bringing a chance of light precipitation tonight into Friday with lingering shower chances far eastern areas on Saturday. Thereafter, a strong ridge of high pressure will move into the area bringing with it a significant warm-up in afternoon temperatures begining this weekend and persisting through next week. Daily SFC winds will see afternoon gustiness. && .TWC WATCHES/WARNINGS/ADVISORIES... None. && $$ Hardin Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
NWS TWC Office Area Forecast Discussion