Area Forecast Discussion
Issued by NWS Tucson, AZ
Issued by NWS Tucson, AZ
557 FXUS65 KTWC 050931 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 230 AM MST Sat Jul 5 2025 .SYNOPSIS...Isolated to scattered storm coverage focused on locales south of Tucson. Temperatures warming back up to above normal levels this weekend then getting hotter next week. && .DISCUSSION...For those still following the start of the monsoon via the average daily dewpoint of 54 degrees or greater in Tucson for 3 consecutive days, July 2 is your start date. Satellite imagery this morning showed a plume of mainly mid-level clouds streaming over the area under SW flow aloft. These clouds extend well to the SW to the remnant circulation of what was Hurricane Flossie, which was located around 325 miles SW of the Baja Spur. Per WPC precipitable water (PW) 12 hour change imagery, PW values over Pima/Santa Cruz counties are possibly up around 0.30". Can`t tell what the actual values are on GOES-19 imagery due to cloud cover but I`m guessing values in the 1.25" to 1.50" range. Sure would be nice to have a 12z Tucson sounding but will have to wait until 18z. Surface dewpoints at 2 am were in the 60s across Pima, Santa Cruz and SW Cochise. For today: Per the CAMs the best area for storms this afternoon would be from SW Cochise county west across Santa Cruz county to Sells. Main threat will be outflow gusts to 45 mph and brief heavy rain and localized flash flooding. Highs will run a few degrees warmer than yesterday. Sunday: All guidance is pointing to Santa Cruz and Cochise counties having the best chances for afternoon/evening storms as the high builds overhead resulting in highs 3 to 6 degrees hotter than today. Next week: Main theme will be hotter daytime temperatures with HeatRisk getting up into the Major category for portions of the area, especially on Wed and Thu. At this time held off on issuing any Extreme heat products. Something for later shifts to ponder. Latest NBM probabilities for 110 degrees for Tucson has 39% on Wed and 13% on Thu. On the precipitation side, with the upper high strengthening over the state, this will limit thunderstorm development. Once again the inherited NBM PoP grids were way to high for this pattern and well above climatology. Thus in coordination with our neighbors, went ahead and lowered PoPs Mon thru Thu but still having chances of afternoon/evening storms mainly S/SE of Tucson. Depending on how the upper high reorientates itself late next week, there is the potential for an increase in daily storm activity from 11th to 13th. Confidence low at this time with the latest CPC 6-10 day outlook for the area leaning above normal for precip. && .AVIATION...Valid through 06/12Z. SCT-BKN 10-14k ft AGL thru 05/19Z...then SCT-BKN 7-12k ft AGL aft 19Z. Isold SCT -SHRA/-TSRA mainly S/SW of KTUS thru 04/04Z with CIGS BKN 5-8k ft AGL and gusty outflow winds up to 40 kts. Surface winds generally WLY 8-13 kts, becoming SLY less than 10 kts overnight. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Expect isolated to scattered showers and thunderstorms this afternoon into this evening mainly south and southwest of Tucson. A decrease in thunderstorm activity is Sunday into next week as the area transitions into a low grade monsoon pattern. An eventual uptick in monsoon activity is possible the middle of next week but will be dependent on how quick the high pressure aloft shifts north. Temperatures heating up this weekend into next week with the potential for very hot temperatures to return the middle of next week. Winds generally light and under 15 mph with the exception of gusty and erratic winds up to 35-45 mph near any thunderstorms. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson