953 FXUS65 KTWC 080837 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 137 AM MST Sun Jun 8 2025 .SYNOPSIS...Dry and hot conditions across southeastern Arizona through the coming week as high temperatures remain several degrees above normal. && .DISCUSSION...The upper pattern this morning is defined by a broad ridge of high pressure across northern Mexico and a weak dry upper low parked off the coast of central California. The upper ridge will slowly shift west today and consolidate into a stronger ridge of high pressure in the Eastern Pacific off the coast of the northern Baja by Monday afternoon. As this shift occurs, the weak upper low off the coast of central California will shift east across Arizona Monday and Tuesday. This disturbance will generally remain dry, but there may be just enough mid-level moisture to result in a few afternoon build-ups near the White Mountains, especially Tuesday. Otherwise, expect to see an amplification of the overall upper pattern the second half of next week as the ridge shifts farther into the Eastern Pacific and is replaced by a high amplitude trough along the West Coast. In response to this trough, expect strong ridging to develop across the central CONUS extending into the Southern Rockies and into Southeast Arizona. Although the ensemble members are still trying to latch onto things, both the 08/00Z operational GFS and ECMWF depict 850-700 mb thicknesses of 1700 m by 00Z Monday. This thickness would correspond to an afternoon high temperature at KTUS around 111 degrees Sunday. The 08/05Z NBM probabilities for KTUS reaching 110+ are 14% on Sunday June 15th, 20% Monday June 16th and back down to 9% Tuesday June 17th. So...hot this week becoming more hot next weekend. && .AVIATION...Valid through 09/12Z. Clear skies through the forecast period. Light and terrain driven wind this morning through 08/18Z...then SFC winds become west to northwesterly 10-15 kts with gusts of 20-25 kts. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Hot and dry through the coming week. Single digit minimum relative humidities through Monday, then mountain locations see a modest increase with 12-20 percent minimum values Tuesday through much of the remainder of the week. A weak weather disturbance will slowly track across portions of Southeast Arizona the first half of the week resulting in a few afternoon build-ups with the possibility of a dry thunderstorm near the White Mountains. 20-foot winds will generally stay 15 mph or less, with occasional afternoon/early evening gusts to around 25 mph due to strong surface heating. && .TWC WATCHES/WARNINGS/ADVISORIES...None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson