Weather forecast: Temperatures set to drop, but it's going to feel just as hot; chance of rain on Sunday
Phoenix, Arizona: According to the Ntional Weather Service (NWS), strong high pressure will continue to impact the region over the next few days, causing excessive heat to persist through at least Friday. Modest moisture levels will bring chances of isolated thunderstorms over eastern Arizona on Thursday, with gusty winds potentially reaching the Phoenix area. By Friday and through the weekend, moisture levels will improve, increasing rainfall chances across the region. Temperatures will gradually decrease to seasonal norms by Sunday.
The high pressure system near Las Vegas remains dominant, but improving moisture levels will help reduce the excessive heat experienced over the past week. Today, increased moisture will likely lead to more widespread convection, initially along the Mogollon Rim and White Mountains. Forecasts indicate isolated strong to severe thunderstorms over the high terrain by mid to late afternoon, with strong outflow winds potentially reaching the lower deserts.
Moisture levels will continue to rise into Friday, especially across the lower deserts, with a significant Gulf moisture surge expected tonight. Although the potential for strong to severe storms on Friday is lower, better moisture may still support storm development in south-central Arizona.
Excessive heat will persist through Friday, with highs in the Phoenix area ranging from 112-116F. However, temperatures will start to decrease on Saturday, with increased humidity making it feel just as hot. Some cloud cover may provide relief from the heat. The weekend forecast for convection is uncertain, with a potential shift in the development of an upper-level low. This may result in limited convection on Saturday, but storm chances should improve by Sunday. Locally heavy rainfall and strong winds could be concerns.
Drier air is expected to spread early next week, limiting convection to south-central and eastern Arizona by Tuesday. Temperatures will continue to improve, with highs falling below 110F in the lower deserts by Sunday. If drier air persists into mid-week, temperatures could rise again.