Excessive heat, red flag warnings now in effect - KPTV - FOX 12

Excessive heat and red flag warnings are now in effect for many parts of Oregon and southwest Washington as 100-degree heat hit the region on Thursday.

FOX 12 meteorologists expect Portland to fall just short of triple-digits on Friday, before cooling off this weekend.

The National Weather Service announced an excessive heat warning from 1 p.m. Thursday to 9 p.m. Friday for much of northwest Oregon and southwest Washington.

This is the hottest stretch since July 27 to July 29 in 2009, when Portland hit high temps of 103, 106 and 106 degrees in succession.

A red flag warning, meaning critical fire weather conditions are forecasted, is currently in effect for many national and state forests. The National Weather Service said the conditions could result in "explosive fire growth for existing and any new wildfires."

The heat will no doubt have an impact on everyone this week, including TriMet, which plans to have extra crews on standby to help with overheating buses or track and overhead power wire issues.

When temperatures climb above 100 degrees, MAX trains cannot go faster than 35 mph, resulting in delays across the system. TriMet officials advise commuters to add some extra time to their commute Thursday and Friday.

The cities of Portland and Gresham each issued total burn bans, effective immediately. That means all outdoor burning, with the exception of barbecue grills, is prohibited.

During the heat wave, experts urge people to take extra precautions if you plan to work or spend time outside:

• When possible, reschedule strenuous activities to early morning or evening.
• Know the signs and symptoms of heat exhaustion and heat stroke.
• Remember to wear lightweight and loose-fitting clothing and drink lots of water.
• Use caution around area waterways and be sure to wear a life jacket.

Beyond the next three days, FOX 12 meteorologists said we're in for a muggy weekend with a chance of a thunderstorm and high temperatures in the 80s. High temps could dip into the 70s next week.

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