Area Forecast Discussion
Issued by NWS Tucson, AZ
Issued by NWS Tucson, AZ
732 FXUS65 KTWC 270947 AFDTWC Area Forecast Discussion National Weather Service Tucson AZ 247 AM MST Sat Apr 27 2024 .SYNOPSIS... Cooler temperatures today with afternoon breeziness is expected as a weather system continues to cross the region. There will be a chance of showers and thunderstorms north of Safford through the White Mountains this afternoon and evening. A warming trend is expected to begin Sunday with temperatures rising above normal by early next week. && .DISCUSSION... A deep upper level trough will continue to slowly push east today, with the center crossing the Four Corners by mid-day. A modest moisture profile along with cooler temperatures aloft is observed towards the center of the low, meaning weak instability should produce isolated shower and thunderstorm activity in the vicinity of the White Mountains today. Better chances will be further north but precipitation probabilities range from 20 to 35 percent in the northern areas of Graham and Greenlee counties. Today will be less windy, but still breezy thanks to a lingering pressure gradient and unidirectional flow through the mid-levels. With the trough axis centered aloft, cooler surface temperatures are expected today with highs around 8 to 12 degrees below normal forecast. As the upper level trough exits east by Sunday, highs will rise about 6 to 8 degrees from today. Then a rapid increase in mid- level heights will bring a quick warm-up early next week with highs back to around 5 to 10 degrees above average by Tuesday. Ensembles continue to favor western CONUS troughing late next week, however ensemble 500mb height trends keep southern Arizona on the warmer and drier side. && .AVIATION...Valid through 28/12Z. FEW-SCT clouds at 8k-11k ft. A few showers and thunderstorms possible near and north of KSAD this afternoon and evening. Winds increase and turn west to northwesterly after 16Z with gusts of 15 to 25 kts, then diminish after 28/04Z. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER... Winds will be breezy this afternoon, though lighter than Friday and below critical levels. Temperatures will also be around 8 degrees cooler than yesterday. With the cooler temperatures minimum relative humidity will be a bit higher across the board, with the driest spots falling to around 15 percent in southeastern Cochise and areas of central to western Pima county. There will be a chance of showers north of Safford this afternoon, which may produce a few lightning strikes. Temperatures quickly warm up by early next week. Minimum relative humidity values in the valleys drop from the 10 to 15 percent range Sunday to the single digits next week while values in the mountains lower from 15 to 30 percent Sunday to 12 to 20 percent next week. && .TWC WATCHES/WARNINGS/ADVISORIES... None. && $$ Public...Edwards Aviation...Edwards Fire Weather....Edwards Visit us on Facebook...Twitter...YouTube...and at weather.gov/Tucson