Monsoon Ramps Up In Phoenix With Strong Storms And Hotter Days Ahead

PHOENIX, AZ — Monsoon season is settling into a familiar rhythm across Arizona this week, bringing afternoon and evening thunderstorm chances along with steadily rising, seasonably hot temperatures, according to the National Weather Service in Phoenix.

Forecasters said the setup is “a fairly typical Monsoon pattern” that should hold through the first half of the week. Storms are expected to fire over Arizona’s higher terrain in the early afternoon before chances shift toward the lower deserts later in the day and into the evening.

In the lower deserts, storm chances range from 10% to 35% over the next few days. Forecasters said abundant moisture will linger through midweek, giving storms plenty of fuel even far from the mountains.

The exact coverage will vary from day to day, depending on subtle shifts in the atmosphere, changes in moisture and how earlier storms move through the region.

Monday could bring the most active weather. The Weather Service said strong storms are possible, with a chance of one or two isolated marginally severe storms, especially in south-central Arizona.

Along a corridor stretching from Phoenix south and southeast toward the international border, forecasters say the chance of 35 mph or stronger wind gusts near storms is running between 50% and 70%.

Heat will climb right alongside the storm chances. Afternoon highs are expected to rise from 102 to 107 degrees Monday into 105 to 110 degrees by midweek, with humidity making Tuesday feel even hotter.

Forecasters said seasonably hot conditions will continue through midweek, with widespread Moderate Heat Risk and locally Major Heat Risk by Wednesday in southeast California. Heat index values could climb as high as 110 to 117 degrees Tuesday, especially in desert areas.

The Weather Service is urging residents heading outdoors to drink plenty of water, limit strenuous activity during peak heat and watch for signs of heat illness.

A shift may arrive late in the week. Forecasters are tracking a disturbance that could move in from the east during the second half of the week, potentially opening the door to more widespread showers and thunderstorms.

By Thursday or Friday, an easterly wave or inverted trough could strengthen storm activity further and raise the risk of heavy rainfall in parts of Arizona.

Temperatures are expected to peak Wednesday before easing off, with lower-desert highs falling back into the 90s or around 100 degrees by Friday.