Forecast Discussion
227 FXUS65 KTWC 091000 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 300 AM MST Fri Oct 9 2026 .SYNOPSIS... Temperatures will be 3 to 10 degrees above normal through Friday, then lowering to near normal Saturday and below normal early next week. Slight chances for precipitation mainly from Tucson south and eastward this afternoon. Thereafter, expect a longer duration period of precipitation chances for our area Saturday through early next week. Gusty winds are also expected, especially Sunday and Monday. && .DISCUSSION... Changes from last discussion - A Wind Adv has been hoisted for SW Pinal, central/western Pima Co from 2AM Sunday until 11PM Sunday night. The other change were to increase coverage of showers/storms this afternoon. Overall guidance, including CAMs, show an upward trend in convection. The main area would be from southern Pinal Co south to the border. Only expecting light rain amounts, but brief heavy rain is possible under cores with wind gusts around 35-40 mph. As of 200AM Rachel is now a Tropical Storm about 840mi/1350km SW of San Diego, CA moving NE 3 kts. Max sustained winds have been lowered to 50 mph, but may increase to around 60 mph as Rachel could see some slight fluctuations in intensity as it interacts with the upper level trof. Regardless of intensity changes or slight track adjustments, our impacts remain the same. For more information on Rachel or Hurricane Simon....see NHC.NOAA.GOV There will be 3 general threats with the remnants of Rachel interacting with an upper level trof. The first will be gusty SW/S winds from central Pima and southern Pinal west. Sustained winds of 25-35 mph, with gusts 45-55 mph likely. These are not necessarily accounting for any convection, which could pull stronger winds to the surface. Given this potential, the SPC has placed locations from Tucson/Eloy west to Ajo in a Marginal Risk for severe weather. The main threat will be locally damaging wind gusts to 60mph, with small hail, and heavy rain. There is a non zero LOW tornado threat Saturday afternoon into the evening. This would be a limited area of western Pima County, including Lukeville, Ajo, and Why. This does not include Tucson. Modest instability, plenty of shear, and increased helicity in the 0-1/0-3km creates the non zero tornado threat. Lastly, there will be scattered to numerous showers and storms Saturday and to a lesser degree on Sunday. General rainfall amounts across the CWA are 0.25-1.0", with 1-2" in the higher elevations. This storm total will occur over a long duration into early next week. While widespread heavy rain is not expected, there is certainly the possibility for localized higher amounts. This is depicted in the CAMs, but confidence is low on placement/timing. The most likely place for higher rainfall totals would be from Ajo to Tucson Sat aftn/eve. Lesser amounts expected east of Tucson to the NM border. While there is no Flash Flood Watch, we will keep an eye out to see if there is a greater threat that develops over the next 24 hrs. For Monday and Tuesday, the main factor for our weather will be the trough axis to our west. There will still be another area of forcing and lift as a cold front moves through the region from late Monday into Tuesday and that is likely to bring us more shower activity and potentially a few thunderstorms as well. Winds will remain gusty on Monday but not nearly as strong as Sunday. Drier air will then move in Wednesday with any lingering precipitation chances Wednesday to the east of Tucson. Above normal temperatures through Friday will give way to near normal temperatures on Saturday, then an extended period of below normal temperatures will occur Sunday through the middle of next week. && .AVIATION /08Z FRIDAY THROUGH 08Z SATURDAY/... FEW-SCT clouds around 9-12k ft agl this morning. SCT-BKN clouds by this afternoon as ISO -SHRA/-TSRA develops mainly south and east of TUS. Gusty winds to 35 kts possible around convection. SFC winds E/SE around 8-15 kts with gusts to 20kts this afternoon. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER... Easterly winds continue through Friday with wind gusts 20-25 mph in the normally susceptible locations for east winds. Minimum relative humidity values will remain 15-30 percent in lower elevations and above 40 percent in high elevation terrain through Saturday. A few storms are possible mainly south and east of Tucson this afternoon. A weather system will move through this weekend into next week bringing a 30-70 percent chance for rain Saturday through early next week. This system will also bring breezy to windy southwest winds Sunday and Monday with wind gusts of 35 to 45 mph on Sunday for much of southeast Arizona. Highest wind potential will be from central Pima County west. && .TWC WATCHES/WARNINGS/ADVISORIES... Wind Advisory from 2 AM to 11 PM MST Sunday for AZZ501-502-505. && $$ Visit us on Facebook, X, YouTube, and at weather.gov/Tucson
NWS TWC Office Area Forecast Discussion