502 FXUS65 KTWC 232008 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 108 PM MST Tue Apr 23 2024 .SYNOPSIS...Dry with seasonable warm temperatures will continue through the first half of the week, then turning cooler and breezy during the latter half of the week. && .DISCUSSION...A ridge of high pressure through the desert southwest today, with temperatures climbing to around 6 to 8 degrees above seasonal normals again this afternoon. A split through the eastern Pacific has brought a low off the southern California coast, which will push slowly across the area over the next 48 hours. It will fill and shear into higher latitude support as it pushes across Arizona, with limited patchy moisture fields this far south. The biggest story for our area will be strong gusty winds Thursday along with decent CAA pushing temperatures back below average. Any significant precip chances will be north of our area, with virga trying to moisten a parched subcloud layer the hard way. That system will lift quickly into the northern Plains Friday and Saturday as a stronger low digs into the new mean trough position through the Great Basin. This stronger and cooler system will also largely stay north of the area, but we could see a few showers in the mountains. Again the main story will be gusty winds and another shot of cooler air as temperatures bottom out around 10 degrees below climo Saturday. Another broad low amplitude ridge will bring a rapid warming trend with temperatures climbing back to several degrees above climo early next week. && .AVIATION...Valid through 25/00Z. SKC conditions thru 24/06Z, then SCT-BKN clouds AOA 20k ft AGL. SLY/SWLY SFC wind at 12-18 kts and gusts to 22-28 kts until 24/02Z, then diminishing overnight. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Dry conditions and above normal temperatures are expected through Wednesday. A weather system will move north of the area on Thursday, dropping temperatures below normal and increasing wind speeds. Wind speeds will be near critical levels over portions of Cochise, Graham and Greenlee counties. Another weather system will move across the area Friday night and Saturday, resulting in even cooler temperatures and highs 5-10 degrees below normal, as well as a continuation of the strong winds to the east of Tucson. Min RH values in the valleys will be 7-14 percent through Wednesday, increasing to 10-20 percent Thursday through Saturday. Min RH values in the mountains will be 10-18 percent through Wednesday, increasing to 20-30 percent Thursday through Saturday. && .TWC WATCHES/WARNINGS/ADVISORIES... None. && $$ Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson |