Area Forecast Discussion
Issued by NWS Tucson, AZ
Issued by NWS Tucson, AZ
030 FXUS65 KTWC 031955 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 1255 PM MST Wed Dec 3 2025 .SYNOPSIS...A weather system will move across the region today, resulting in cooler temperatures, a chance of showers through tonight and breezy conditions. Cooler temperatures behind the system will lead to below normal high temperatures into this weekend and cool morning low temperatures Friday and Saturday mornings. Dry weather returns on Thursday and continues into next week. High temperatures warm to above seasonable levels Sunday through next week. && .DISCUSSION...In the large scale picture an upper low over northern Arizona will track east into northern New Mexico tonight and east into the southern plains Thursday. Baggy troughiness continues across the desert southwest through Friday, with weak ridging Saturday and then more substantial ridging Sunday into the middle of next week. As the upper low moves east today/tonight it will drag a frontal boundary across the state. There will be a chance (10-30 percent) of valley rain/mountain showers through the evening hours tonight mainly to the east of the Tucson Metro. Precipitation amounts are expected to be very light, trace amounts to a couple of hundredths (potentially around a tenth of an inch in the Sky Islands and White Mountains). Snow levels will be around 7000 feet this afternoon, lowering to around 6000 feet late tonight, with snowfall totals of around one inch. Little to no impacts are anticipated with the rainfall/snowfall amounts with this system. The main impacts will be: the breezy southwest to west winds this afternoon/early evening mainly southeast of Tucson (sustained wind speeds of 15-20 mph and gusts to 30-35 mph); and the colder low temperatures Friday and Saturday mornings south and east of Tucson. Low temperatures will be in the upper 20s to lower 30s across much of the lower elevations of Santa Cruz, Graham and Cochise counties and even colder (mid 20s) in the typical cold spots of eastern Santa Cruz and the Sulphur Springs valley of Cochise County. Lows will likely even be in the mid to upper 30s in the outlying areas surrounding the Tucson Metro, especially Saturday morning. Have issued a Freeze Warning for the lower elevations of Santa Cruz, Graham, Cochise and the Altar Valley from 2 AM MST to 9 AM MST Friday morning. Below normal high temperatures continue through Saturday. High temperatures then warm to 2-4 degrees above normal on Sunday as ridging begins to work into the area from the west. Highs then warm to 5-8 degrees above normal early to mid next week as stronger ridging builds into the desert southwest. After tonight, dry conditions are expected through at least next week and next weekend. In fact, the Climate Prediction Center has southeast Arizona in likely above normal temperatures (70-90 percent) and leaning below normal precipitation (33-40 percent) in the 8-14 day time frame (Dec 10-16). && .AVIATION...Valid through 05/00Z. SCT-BKN clouds at 5k-8k ft AGL thru 04/06Z, then slowly clearing skies from west to east. FEW-SCT clouds at 7k-10k ft AGL mainly from KTUS eastward aft 04/12Z. ISOLD valley -SHRA/mountain -SHSN thru 4/06Z primarily east of KTUS. SFC wind SWLY/WLY at 12-20 kts with gusts to 25-30 kts thru 04/02Z, then diminishing SFC wind. The strongest SFC wind will be to the south/southeast of Tucson in the vicinity of KALK and KDUG. Aft 04/05Z, SFC wind will be less than 12 kts thru the remainder of the forecast period, favoring a WLY/NWLY direction Thursday afternoon. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...A weather system will move across the region today, resulting in cooler temperatures, a chance of showers through tonight and breezy conditions. 20-foot winds will be from the west/southwest at 15-20 mph, with gusts 30-35 mph over portions of eastern Santa Cruz and Cochise counties through early this evening. Min RH values will be in the 25-35 percent range through Friday, lowering to 20-30 percent this weekend. Dry weather returns Thursday and continues into next week. High temperatures will be below normal through Saturday, warming a couple of degrees above normal on Sunday and then 5-8 degrees above normal next week. && .TWC WATCHES/WARNINGS/ADVISORIES... Freeze Warning from 2 AM to 9 AM MST Friday for AZZ503-507>509. && $$ Zell Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson