Forecast Discussion
290 FXUS65 KTWC 101800 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 1100 AM MST Fri Apr 10 2026 .SYNOPSIS... High temperatures will be 4-8 degrees above normal the next couple of days. Breezy winds each afternoon through Monday. Cooler air leading to high temperatures 4-6 degrees below normal early next week and bring a slight chance for precip north and east of Tucson Monday. && .DISCUSSION... The current upper air pattern is defined by a strong cut off low situated off the coast of northern California. While this system is fairly dry for us, this is leading to increased cloud cover and breezy west to southwest afternoon winds today. There were indications for a slight chance (10-20%) for precipitation for areas out east today, however in the last 12 hours those signals have decreased. While there are strong upper level winds, there is a lack of instability and moisture. Satellite derived PWATs observe the greatest values range between 0.25 to 0.5 inches with surface dew point forecast to be in the 30s this afternoon. High temperatures will be 4-8 degrees above normal today with temperatures in the 80s to low 90s. Starting this evening, the upper level pattern will be fairly progressive with several shortwave troughs passing through the region. The aforementioned cut off low will be, essentially, absorbed by a secondary cut off low moving in from the Aleutians early Saturday. The remnant energy from the first low will transcend to a shortwave trough that will extend southward as far as Central Mexico. This shortwave trough will bring very dry conditions and breezy southwest to west winds Sunday afternoon. Relative humidity will drop into the teens to single digits and sustained wind speeds 15-20 mph and gusts 25-30 mph lead to near critical fire weather conditions forecast. A Fire Weather Watch has been issued from eastern Pima and Pinal counties to the Arizona/ New Mexico border for Sunday afternoon. Winds will continue to stay elevated Monday (and even be little bit stronger than Sunday) however, the secondary cut off low will move into the Great Basin area introducing moisture into the region lessening the concern for fire weather conditions. As the system passes through Monday and Tuesday temperatures will lower to near normal to just below normal with highs in the 70s to low 80s. There is a chance (15-30%) for light precipitation Monday night into Tuesday focused to areas north and northeast of Tucson. By the middle of the week semi- zonal flow with general troughiness to the west will return, raising temperatures to near normal with typical afternon breezes. By the end of the week there is potential for another trough to push into southern Arizona however there is disagreement amongst the models how deep this trough will extend and the associated intensity. && .AVIATION... Valid though 12/00Z. SCT-BKN clouds AOA 20k feet AGL for most of the period with FEW-SCT 10k-15k AGL. Some cloud buildups will be possible along the AZ/NM border this afternoon with additional afternoon buildups Saturday. Low confidence that any outflows from buildups will affect any terminals. Sfc winds 10-15 kts with gusts 20-25 kts this afternoon, then subside after 12/03Z becoming light and terrain driven again. Winds become southwest and increase to 12-16 kts with gusts to 25 kts after 11/18Z. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER... Afternoon winds west/southwest 10-15 mph today as a Pacific system approaches the region. Southwest winds increase further this weekend as a system crosses the region, becoming 15-20 mph with gusts 25 to 30 mph. With this system continuing to look drier, the combination of critical winds and relative humidity will result in the potential for fire weather concerns as early as Saturday, but especially on Sunday. RH values will likely be a bit too high on Saturday and Monday. As a result a Fire Weather Watch is in effect for Sunday. While winds remain gusty early next work week, cooler temperatures and increased moisture Monday should help mitigate widespread fire weather concerns. Thereafter, winds generally 15 mph or less through the middle of next week. && .TWC WATCHES/WARNINGS/ADVISORIES... Fire Weather Watch from Sunday morning through Sunday evening for AZZ150>152. && $$ Malarkey/Edwards Visit us on Facebook, X, YouTube, and at weather.gov/Tucson
NWS TWC Office Area Forecast Discussion