Forecast Discussion
147 FXUS65 KTWC 090851 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 151 AM MST Fri May 9 2025 .SYNOPSIS...High temperatures will be 6-10 degrees above normal today through Monday with Tucson possibly hitting 100 degrees Sunday and Monday. Winds will be breezy out of the east Saturday, then breezy out of the west Monday through Wednesday. Temperatures cool to a few degrees below normal by mid next week. && .DISCUSSION...High pressure continues to build over the region and is expected to continue into the weekend. This ridge will lead to temperatures 8 to 10 degrees above normal and a chance for areas mainly Tucson westward to reach 100 degrees Sunday and Monday. For Tucson, current probability of reaching 100 degrees on Sunday is 62 percent and 25 percent on Monday. At the same time an east to west pressure gradient sets up tomorrow into Sunday thanks to a fairly strong surface high pressure in the Great Plains. This will lead to easterly winds each day with the strongest winds in the Gila River Valley. The gradient will be strongest on Saturday, which is when the strongest winds are expected. This will lead to elevated fire weather conditions with some brief localized areas of Red Flag conditions. Not expecting more widespread Red Flag conditions because the timing of the strongest winds is in the morning when RH values will be above 15 percent. By the time RH values drop in the afternoon, winds will begin to weaken. Towards the beginning of next week the ridge begins to flatten and is followed by a fairly strong Pacific low that moves into the Pacific Northwest then pushes southward into the Great Basin. This system, though dry in our area, will bring strong gusty west winds Monday through Wednesday with the strongest winds expected on Tuesday. These strong winds, along with low RH, and dry fuels could lead to more widespread Red Flag conditions Tuesday afternoon from Tucson eastward. Temperatures will drop to normal or a few degrees below normal Tuesday through the end of the work week. && .AVIATION...Valid through 10/12Z. SKC until 09/17Z when FEW to SCT mid to low level clouds AOA 10-15k ft AGL develop across the area. These clouds will dissipate becoming SKC by 10/08Z and for the remainder of the forecast period. SFC winds early this morning will be fairly light 5-10 kts and variable. SFC wind will increase to 10-15 kts from the east by 09/18Z then gradually weaken into the afternoon and evening hours becoming light and variable overnight. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Temperature continues to warm and humidity continues to drop into the weekend as high pressure builds. A backdoor front will result in breezy southeast winds east of Tucson as early as Friday, but especially Saturday. Widespread critical fire weather conditions are not anticipated with this feature, although localized/brief near critical conditions will be possible Saturday across portions of southeast Arizona. Otherwise, the warm conditions we will experience today into this weekend will back off the first half of next week as a dry trough moves into the region. This will result in strong and gusty winds returning to the area Monday through Wednesday, with the strongest winds/potential for more widespread critical fire weather conditions impacting the region Tuesday. && && .TWC WATCHES/WARNINGS/ADVISORIES... None. && $$ Public...Malarkey Aviation...Aviation Forecaster Fire Weather....Fire Weather Forecaster Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson
NWS TWC Office Area Forecast Discussion