Phoenix Weather Monday: Sunny 104°F With Monsoon Storms Building Tonight
Phoenix is sunny and hot today, with highs near 104°F and a light southwest wind around 0 to 10 mph — a good day to knock out outdoor plans before monsoon moisture pulls back into the Valley tonight. The National Weather Service in Phoenix says shower and thunderstorm chances are climbing today and Tuesday, especially over the high terrain, with isolated storms possible in the lower deserts too.
Today’s Setup
Skies stay clear through the afternoon with only a 7% chance of rain. The change comes after sunset: forecasters expect a slight chance of showers and thunderstorms developing between 7 and 9 PM, then better chances through 11 PM, as a mesoscale disturbance and an inverted trough help spark convection. Overnight lows only dip to around 84°F before climbing back to 86-88°F by daybreak — classic monsoon mugginess.
Rain, Flash Flood, And Heat Risk
The Weather Prediction Center has placed much of Arizona, including the Phoenix area, in a Slight Risk for excessive rainfall today, warning that afternoon storms could again trigger localized flash flooding like the pattern seen on recent days. If you’re near washes at South Mountain Park or the Camelback trailheads this evening, watch the sky and avoid low-lying crossings if storms fire up. East-southeast gusts to 25 mph are possible tonight, so secure loose patio items before you turn in.
Diamondbacks, Concerts And Weekend Plans
The Arizona Diamondbacks host the Athletics at Chase Field starting Tuesday, July 21, with more games July 22 — expect a hot 103°F gameday with a 25% chance of a stray storm, so pack patience for any tailgating. Gear up with an Arizona Diamondbacks jersey before first pitch. Music fans have options too: Darius Rucker brings his Songs Of Summer Tour to Arizona Financial Theatre on July 23 (grab a Darius Rucker t-shirt and tickets on SeatGeek), while CA7RIEL & Paco Amoroso hit the same venue July 24 — check our event coverage before grabbing tickets on StubHub. Theater fans can catch Les Miserables at Phoenix Theatre-AZ on July 22.
What To Wear Or Bring
Mornings before 9 AM are your best window for golf or a run — bring a hydration running vest regardless, since even the “cool” hours run warm here. Anglers should fish early too; a portable fish finder helps make the most of a short window before the heat sets in.
Tonight’s Dinner
With clear skies and calm winds this evening, it’s perfect grilling weather. Fire up the propane gas grill for burgers, steaks, or grilled chicken with corn on the cob, and keep an instant-read meat thermometer and grill brush and scraper set handy. Want to cool off first? The 2-Person Intex Floating Lounge with Cooler is just $24 on Amazon this week for backyard pools. Need ingredients? You can order groceries on Amazon and have everything for tonight’s dinner delivered to your door.
Next Few Days
Tuesday looks similar — 103°F with a 25% storm chance. The NWS expects drier air to take over by Thursday, cutting storm chances to slight at most, but temperatures climb sharply, with Major to Extreme Heat Risk likely spreading widely by the weekend. Plan strenuous outdoor activity for early morning through midweek before the heat ramps back up.
