Area Forecast Discussion
Issued by NWS Tucson, AZ
Issued by NWS Tucson, AZ
167 FXUS65 KTWC 112043 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 143 PM MST Fri Jul 11 2025 .SYNOPSIS...Above normal temperatures continue through the weekend. Expect isolated thunderstorms limited to areas near the International Border from Nogales eastward into this evening and along the NM border Saturday. An increase in monsoonal activity on Sunday, especially for locales east of Tucson and then next week for the entire forecast area. As moisture and storm chances increase next week, temperatures will drop back down to seasonable levels. && .KEY MESSAGES... - Low grade monsoon pattern through Saturday. Isolated to low end scattered storm chances today mainly along the Int`l border from Nogales. For Saturday, thunderstorm chances expand northward along the NM border into the White Mountains. - Slightly above normal temperatures this weekend, then cooling trends start around Tuesday with near to slightly below normal temps mid to late next week. - Monsoonal activity ramps up again as early as Sunday, with increased moisture. More active monsoon pattern through next week. .DISCUSSION...Latest visible satellite imagery shows partly cloudy skies across southeast Arizona this afternoon with a nice cumulus field due to the increase in lower level moisture. However, the cumulus is fairly flat as subsidence and warmer temperatures aloft is preventing much in the way of vertical build-ups. An east- west elongated mid/upper level high is located from southern Arizona to off the southern California coast. This is resulting in continued northwesterly flow aloft with continued mid level drier air advecting in. Latest HREF/CAMs continue to show isolated to low end scattered thunderstorms chances primarily confined to the southern half of Cochise County into the early evening with slight chances extending as far west as Nogales. Meanwhile, breezy west to northwest winds continue this afternoon, especially in the upper Gila River Valley including Safford where gusts are currently around 35 mph. The aforementioned mid-upper level ridge remains fairly stationary through Saturday with once again a low grade monsoon day. Perhaps a few more storms in the White Mtns and along the NM border extending into southern Cochise County but overall a low activity day. Gusty outflow winds remain the primary threat with any storms. High temperatures similar to today, with a degree or two of cooling in spots. Sunday will be the transition day into a more active pattern that will continue through next week. While the high center will remain to our west, the orientation of the high in combination with of mid- upper level troughiness to our east will result in more favorable diffluence aloft near the NM border. This will help in storm development over the White and Gila Mtns that will push to the SW into valleys of Graham/Greenlee/Cochise Counties. More uncertainty on whether storms make it as far west as Tucson, and this is something we`ll be trying to get a better handle on in the next day or so. Certainly increasing likelihood of strong gusty outflow winds coming in from the east by Sunday evening even if the storms don`t make it as far west of Tucson. Next week is shaping up to be an active monsoon week right as we get into the heart of the monsoon from a climatological perspective. The mid-upper level high will gradually shift towards the Four Corners with NE flow over SE Arizona early in the week, which will then transition to east to southeast flow with the high to our northeast and a mid level disturbance to our south and west helping to pump in additional moisture with elevated storm chances. This type of setup would yield storm impacts leaning towards a severe threat at the beginning of the week with a transition to both a severe and flash flood threat as the week progresses. && .AVIATION...Valid through 13/00Z. SFC winds WLY/NWLY 10-15 kts thru 12/04Z with gusts 20-25 kts. Stronger winds for KSAD and vicinity with gusts up to around 30 kts. SFC winds subside to 12 kts or less aft 12/04Z thru 12/19Z before becoming WLY/NWLY at 10-15 kts thru end of the valid period. SKC-SCT clouds 8-13k ft AGL thru the valid period with isolated -SHRA/-TSRA near KDUG thru 12/03Z and again aft 12/20Z. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Isolated thunderstorm coverage is expected to the south and east of Tucson, mainly along the International Border through Saturday. The main threat for storms will be the potential for strong gusty and erratic outflow winds 40-45 mph. Otherwise, an uptick in monsoon activity is expected beginning Sunday and through next week as the upper high shifts to a more favorable location aloft. Temperatures will remain above normal through Monday, then drop back down to near or slightly below normal by mid to late next week. Winds will remain westerly from 10-15 mph, with occasional gusts at or above 20 mph, with the exception of stronger winds in the Gila River Valley through Saturday with northwest sustained winds around 15 to 20 MPH gusts to 30 MPH. Afternoon RH values in the low lying areas will be between 20-25%. && .TWC WATCHES/WARNINGS/ADVISORIES... None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson