Jul. 7--So much for sneaking through the summer without a stretch of blast furnace heat.

High temperatures approaching, if not exceeding, 115 degrees are expected in the Valley by Friday and continuing into the weekend, according to the National Weather Service.

Because of the potential danger, the Weather Service anticipates issuing an excessive heat warning effective for two days, perhaps three.

This heat wave comes after a remarkably mild June and an early beginning to the monsoon, and so it seemed possible residents would not have to endure scorching days and oppressive nights.

Wrong.

Usually at this time of year, the daytime highs are around 107 and the overnight lows about 82. But on Saturday, in the hottest parts of the Valley the forecast high is 116 with a minimum temperature early Sunday of 91.

Ken Waters, warning coordinator meteorologist at the Weather Service's local office, said it is not uncommon for a hot spell to occur after the monsoon's arrival.

But what is odd, Waters added, is there was no hot spell before early July.

"A lot of June was more like an April (weather) pattern," Waters said of last month's cool and cloudy conditions. "We did not have that significant heat wave; it just absolutely never came. And then we immediately jumped into the monsoon."

Through Tuesday, in 2009 there had only been two days when the thermometer reached 110 or higher, with the most recent coming Sunday. By this time in 2008, there had been 16 such days, including a run on 11 straight.

In looking at the last 30 years of weather data, in an average summer there are 18 days with maximum temperatures of 110 degrees and hotter.

There may be some relief late in the weekend, Waters said, as the monsoon humidity is expected to return. Forecasters are monitoring tropical activity in the eastern Pacific Ocean, and if that source of moisture is tapped, Waters said, "it looks like the spigots could be turned on big-time next week."

Meanwhile, the human services organization Community Information and Referral is preparing to open hydration stations and refuge locations, staffed by volunteers, where the elderly, disabled and homeless can come to receive water or just get out of the heat.

Also, there are donation/collection sites for people to drop off water and items such as light-colored T-shirts, sunblock, socks and underwear, hats and pre-packaged snacks.

Donation/Collection Sites

CHANDLER

--Chandler CAP

650 N. Arizona Ave.

7 a.m. to 4 p.m., Monday through Friday

--The Salvation Army -- Chandler Corps

85 E. Saragosa St.

8:30 a.m. to 5 p.m., Monday through Friday

MESA

--A New Leaf

2254 W. Main St.

7 a.m. to 7 p.m., daily

--East Valley Men's Center

2345 N. Country Club Road

7:30 a.m. to 4 p.m., daily

--Mesa CAN

635 E. Broadway Road

8 a.m. to 5 p.m., Monday through Friday

--Fountain of Life Fellowship

6052 E. Baseline Road, Ste. 137

10 a.m. to noon, Thursday

For more information, call (602) 263-8856.

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