Your smart phone weather app isn't lying: Portland is expected to see temperatures as high as 107 degrees this week.

The National Weather Service has placed an Excessive Heat Watch on the region, running from August 1-4, when Portland could see temperatures up to 107 degrees, the highest temperature ever measured downtown.

"It's not gonna be fun," meteorologist Jeremiah Pyle tells WW.

Portland hasn't hit 107 degrees since 1981 and before that, 1940, according to the National Weather Service.

The NWS also notes that only seven times since 1940 has Portland had three consecutive days of temperatures higher than 100 degrees. The last time it was 106 degrees in Portland was July 28-29 in 2009.

Meteorologists are saying this week could beat that record: We could see more than three consecutive days of temperatures higher than 100 degrees. The National Weather Service is currently forecasting 99 degrees on Tuesday and 100 degrees on Friday.

Seeing temperatures hotter than 107, however, isn't in the forecast.

Anything's possible, but that would be surprising," meteorologist Jeremiah Pyle tells WW.  "That would be an all-time new record. 105 to 107 is the range we're forecasting for the Metro area."

The lowest temperature Portland has seen this summer was 60 degrees on June 12, meaning that in less than two months, the temperature will have risen by nearly 80 percent—not including overnight lows.

Unfortunately, overnight temperatures won't provide much solace this week.

"We're not going to get a whole lot of help with the overnight temps," Pyle says. "By Tuesday night, we're going to be struggling to get below the upper 60s, and then Wednesday and Thursday night, we might not even drop below 70."

But where is this massive heat wave even coming from? Pyle explains that it's "basically just a really warm air mass." There's been a strong pressure building up in the Southwest region on the country, and now it's strengthening and moving into the Pacific Northwest region, he says.

But luckily, it won't bring humidity.

"The one saving grace is it's not going to be humid," Pyle says. "It's going to be on the dryer side. We're not looking at Midwest humidity or anything."

The City of Portland is preparing for this week's heat wave. Here's a link to all the cooling centers and a map:

You can also sign up for cooling center email alerts here.

Senior citizens are among the most sensitive populations to high temperatures. Meals on Wheels is currently accepting fan donations to be delivered to homebound seniors this week. Here's a complete list of centers where you can drop fans off.

Heat exhaustion and heat stroke will be very real concerns this week. The National Weather Service released this graphic to help people understand the signs and how to get help: