Arizona weather forecast: Big changes bring heavy rain and storm threats

PHOENIX - Two more beautiful days remain ahead before big changes arrive to the forecast.

What to Expect:

The forecast high reaches 87 degrees on Wednesday afternoon. It will be mostly to partly sunny with passing high clouds expected over the state. Thursday remains near or above average with a forecast high of 86 degrees in Phoenix. The sky turns from partly cloudy in the morning to mostly cloudy by the afternoon. A few showers may pass over eastern Arizona or the High Country later in the day. A few additional light and spotty showers will be possible around the state starting Thursday overnight.

Tapping into leftover tropical moisture to the south, scattered showers and thunderstorms will pass through Arizona on Friday. The best chance for storms will be over southern and central Arizona, including Phoenix. Rain totals may reach 0.5 inches to 1 inch (or more) over areas impacted by stronger storms. Gusty winds will be possible, too.

Halloween Weather:

Heading into Saturday, there will be a lull in activity. Drier air will take over the forecast through the day on Saturday. By Saturday night, however, a new round of rain will begin to impact the state, spreading from the southwest. The next round of rain will become more widespread and steady to heavy through the morning to afternoon on Sunday. Again, some areas may pick up 0.5 inches to 1 inch or more.

Temperatures will respond to this changing pattern as a large trough moves against the West Coast, and disturbances pulse up from the southwest. This will drop the forecast high to the middle 70s on Friday, upper 70s on Saturday, and low 70s on Sunday. Overnight temperatures will eventually fall to the upper 50s by early next week, too.

For now, Halloween looks okay. There will be a low chance for a few passing light showers during the day in Arizona. The best chance will be areas of higher elevation, but a spot shower or two could pass Phoenix as well. Through the early evening, the drier pattern will remain. This means early trick-or-treaters have a better chance of good conditions to get outside. However, as the night progresses, rain chances will quickly increase, spreading west to east across Phoenix.

With two rounds of potentially heavier rain and storms, there will be an increased risk of flooding around the state as well.

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.

Know your limitations

• Hydrate (begins day prior to hike/exercise, hour before hike, during and after).
• Wear proper clothing, lightweight and light color, protect head, proper shoes.
• Always carry a cell phone and best to hike with company.
• Always tell someone where you are hiking and when to plan to return.

Preventing heat exhaustion/heat stroke

The Arizona Department of Health Services stated the following precautions can be taken to prevent heat exhaustion or heat stroke:

• Stay in air-conditioned buildings.
• Find a cooling center/hydration station.
• Limit outdoor activity during the hottest part of the day (mid-day).
• Check on at-risk friends, family, and neighbors at least twice a day.
• Drink water before, during, and after working or exercising outside.
• Check the UV Index.
• Check the heat risk map.

Road Conditions

• Call 511 anywhere in Arizona or 1-888-411-ROAD (7623)

Rain/flood safety tips

The American Red Cross' tips for heavy rain situations and flood safety:

• Turn around don’t drown! If you must drive and you encounter a flooded roadway, turn around and go another way.
• If you are caught on a flooded road and waters are rising rapidly around you, get out of the car quickly and move to higher ground.
• Tune in to your local radio, NOAA radio, or news channels for the latest updates.
• If your neighborhood is prone to flooding, be prepared to evacuate quickly.
• Follow evacuation orders and do not attempt to return until officials say it is safe.
• If power lines are down, do not step in puddles or standing water.
• If power is out, use a flashlight. Do not use any open flame as alternate lighting.

Preparing for a severe thunderstorm 

The American Red Cross' tips for preparing for a severe thunderstorm:

• Put together an emergency kit.
• Know your community’s evacuation plan.
• Create a household disaster plan and practice it.
• Purchase a battery-powered or hand-crank radio
• Discuss thunderstorm safety with members of your household. Be aware that a thunderstorm could produce flooding.
• Pick a safe place in your home for household members to gather during a thunderstorm. This should be a place where there are no windows, skylights, or glass doors, which could be broken by strong winds or hail and cause damage or injury.

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