908 FXUS65 KTWC 262049 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 149 PM MST Mon Jun 26 2017 .SYNOPSIS...The record heat is over but temperatures will still be hot through the week. We still have enough moisture for isolated to scattered showers into this evening and then again Tuesday across portions of Cochise County. Thereafter, dry conditions are expected to prevail the remainder of the work week. && .DISCUSSION...Flow pattern aloft shows a 500 mb high centered to our southwest across the northern Baja Peninsula. This is resulting in north-northeasterly flow aloft across the area. Still adequate moisture to work with this afternoon as PWAT values hang around 1 inch with surface dewpoints in the 40s to lower 50s. Current KEMX radar imagery shows thunderstorms mainly east of Tucson, primarily across the higher terrain. The expectation is most of the convection will remain east of Tucson, with the metro area being on the western fringe as the storms move south off the higher terrain such as the Catalinas. Main threat will be gusty outflow winds with areas of blowing dust possible along with brief downpours. A pretty good push of outflow is already about to come off the Mogollon Rim towards the Safford area. Otherwise, showers and thunderstorms will gradually diminish after sunset. As the subtropical high remains to our south and weakens slightly for the next few days with increased westerly flow aloft, this will allow drier air to move into the forecast area along with some enhanced afternoon breezes in the Gila River valley. For Tuesday, just a slight chance of thunderstorms mainly across portions of Cochise County, then just a few build-ups along the international border the remainder of the work week but still expected to remain dry. Temperatures will cool down a couple of degrees this week but still slightly above normal which is still quite hot. Signs are there per both deterministic and ensemble guidance that some increased moisture will move back in for a return to some thunderstorm chances south and east of Tucson this weekend into early next week. && .AVIATION...Valid thru 28/00Z. SKC-SCT clouds 10-15k ft AGL from KTUS west, and mainly SCT-BKN clouds at 8-12k ft AGL east and south of KTUS thru the forecast period. Isolated to scattered SHRA/TSRA mainly east and south of KTUS through this evening, with isolated SHRA/TSRA Tuesday afternoon near KDUG and KOLS. Surface wind north to northwest through this evening, then less than 12 kts tonight and Tuesday morning. A few of the stronger TSRA may produce wind gusts to 40 kts and brief MVFR conditions, especially near KDUG/KOLS. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Isolated to scattered thunderstorms generally east and south of Tucson through Tuesday. Dry conditions Wednesday through Friday, then isolated to scattered showers and thunderstorms return south and east of Tucson starting this weekend. 20-ft winds will exhibit diurnal trends with speeds mainly less than 15 mph through Tuesday. Breezy west to northwest winds of 15 to 20 mph are likely on Tuesday and Wednesday afternoons, especially in the upper Gila river valley. Periods of erratic gustiness may occur due to strong daytime heating and/or thunderstorm outflows. Lighter wind speeds returning by this weekend. && && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ GL Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson |