Area Forecast Discussion
Issued by NWS Tucson, AZ
Issued by NWS Tucson, AZ
902 FXUS65 KTWC 031002 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 302 AM MST Wed Jul 3 2024 .SYNOPSIS...Chances of showers and thunderstorms today then gradually diminishing during the rest of the week. Some storms will generate strong winds and locally heavy rainfall. With high pressure building in from the northwest, daytime temperatures will be trending hotter Friday into at least early next week. && .DISCUSSION...A few light showers were occurring across the area as of 240 am. Infrared satellite imagery showed plenty of debris cloudiness over the area along with a MCV south of the New Mexico boot, moving to the NE. PW value this morning are generally in the 1.3" to 1.6". These values will gradually decrease today with values down about a tenth of an inch or two as the flow aloft turns to the N with high pressure off west coast nosing in. Scattered showers and storms this afternoon/evening with Intl border locals seeing best chance of storms. Highs above normal. Ebb and flow of moisture will keep isolated to scattered storms around on the 4th and Friday. Again best chances will be near the Intl border. Highs Thursday similar to today then turning hotter on Friday. With the heat risk in the major category for the lower deserts of Pima and Pinal counties, went ahead and hoisted up a Excessive Heat Watch for Friday. A few places will be near July 5th record highs. See climate section below. This weekend into next week, hanging on to enough moisture for continued slight chance PoPs mainly south and east of Tucson. Turning hotter early next week where heat risk will likely be in the major category. Later shifts will ponder hoisting Excessive Heat Watches. && .AVIATION...Valid through 04/12Z. FEW-SCT clouds (locally BKN) at 9k-12k ft AGL and SCT-BKN clouds AOA 20k ft AGL thru 03/18Z, with ISOLD -SHRA/-TSRA. Between 03/18Z and 04/05Z, SCT-BKN clouds at 7k-10k ft AGL and ISOLD-SCT TSRA/SHRA. MVFR conditions near TSRA, with mountain obscurations, VSBY restrictions and gusts to 40+ knots. Aft 04/05Z, gradual clearing thru the remainder of the forecast period. Outside of TSRA outflows, SFC wind generally 12 kts or less favoring a WLY/NWLY direction during the afternoon/early evening hours and variable in direction at other times. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...There will be the daily chance for isolated to scattered showers and thunderstorms mainly from Tucson east and south. High pressure aloft will build to our northwest late this week into early next week, which will result in hot conditions. With the hotter temperatures and some of the deeper moisture getting pushed to the south and east of the region, min RH values will lower into the 10-18% range across the lower elevations and 15-30% in the higher elevations Friday into early next week. High temperature will warm considerably late this week through the weekend, with highs 106- 113 degrees from Tucson westward and in the Gila River Valley, and in the upper 90s to 105 degrees across Santa Cruz and Cochise counties. Excessive Heat will likely be an issue during this time frame. Outside of any thunderstorm outflow winds, 20-foot winds will generally be 15 mph or less each afternoon with occasional gusts to 20-25 mph through the weekend. Early next week there will be the potential for more elevated wind speeds in the 15-20 mph range, especially east of Tucson. && .CLIMATE... Record or near record high temperatures Friday Date Jul 05 FCST RCD/YR Tucson Intl Airport 109 111/2018 Organ Pipe Cactus 111 115/1983 Picacho Peak 113 113/2007 Safford Ag Station 108 109/2007 && .TWC WATCHES/WARNINGS/ADVISORIES... Excessive Heat Watch from Friday morning through Friday evening for AZZ501-502-504-505. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson