Arizona weather forecast: Near-record highs in Phoenix expected on St. Patrick's Day

Name: Evening Weather Forecast - 3/17/26
Uploaded: 2026-03-17T07:49:41-07:00
Description: It's going to be a hot week, but we are also expecting slightly cooler weather for the Phoenix area next week.

Evening Weather Forecast - 3/17/26

It's going to be a hot week, but we are also expecting slightly cooler weather for the Phoenix area next week.

PHOENIX - The heat is on, and it's only getting hotter!

Tuesday:

Tuesday was a warmer day in Arizona, and a few records were broken.

Phoenix had a record warm morning of 70 degrees. Prescott had a record warm afternoon at 82 degrees, and Flagstaff had a record-tying warm afternoon. This is just the beginning of a record-setting streak for all cities across Arizona.

This Week:

An exceptionally strong ridge of high pressure is building over the southwest and will center over Arizona by Wednesday. As this happens, the forecast highs climb from near-record level to record-smashing level.

The Valley will only cool to 70 degrees by Wednesday morning, which will be a record warm morning low. Wednesday will be a sunny day, with a high of 101 degrees in Phoenix.

Extreme heat warnings will go into effect for western Arizona, the Grand Canyon and Verde Valley on Wednesday. They will begin for the rest of the Sonoran desert, including the Valley, on Thursday. The warnings will remain in effect until Sunday, as the entire state sees record-setting warm temperatures.

Remember, some Phoenix city trails will be closed from 8 a.m. to 5 p.m. for the duration of the extreme heat warning.

The peak of the heat wave will be Thursday through Friday, as temperatures climb from 104 to 106 degrees.

Dig deeper:

Currently, the all-time record temperature for March in Phoenix is 100 degrees. The all-time record for April in Phoenix is 105 degrees. This week we may break both records. The current record for 90+ degree days in a row in March is six days. We'll also blast through that record.

Finally, we'll set a record for the earliest triple-digit day. The current record is March 26, set in 1988.

In addition to setting records in Phoenix, much of the state will see record high temperatures and even all-time records. In fact, the whole region will begin setting records in the next couple of days.

You can always check the latest weather conditions by visiting the FOX 10 Phoenix weather page, or download the Free FOX 10 Weather app, which is available on Apple iOS and Android.

Scroll down this page for satellite and radar, day planner, records, current temperatures, 10-day forecast, forecast highs, and recent rainfall totals, plus live video feeds.

The following heat safety information was provided by the Scottsdale Fire Department.

What are Heat Emergencies?

Heat Cramps: Profuse sweating, fatigue, extreme thirst, muscle cramps

Heat Exhaustion: Headache, dizziness, weakness, nausea/vomit, Cool/moist skin

Heat Stroke: Elevated temp. +103degrees, confusion/irrational behavior, dry/hot skin, rapid shallow breathing, rapid weak pulse (shock), seizures, unconscious

What to do

Get person into shade or cool location
Cool person with cool, wet cloths (neck, groin, armpits, head) and fan body
Sip cool water if person is alert
For muscle cramps, massage muscles gently, but firmly until relaxed
*If symptoms worsen, call 911

What not to do

Do not give anything by mouth if person is vomiting, unable to swallow or unconscious
Do not underestimate the seriousness of a heat emergency
Prevention/Preparation for hike/exercise in heat