Record heat sears the weekend, but ‘cooler’ days in sight

The brutally hot summer continues with high temperatures in record territory for the holiday weekend, but a brief reprieve is in sight.

An excessive heat warning remains in effect until 8 p.m. Monday with forecasters calling for dangerously hot conditions with temperatures as high as 116 in parts of south central Arizona, said the National Weather Service in Phoenix.

Forecasters warned of an increase of heat-related illnesses, including heat cramps, heat exhaustion, as well as heat stroke, which can be fatal.

Last week, they had said the Labor Day weekend was shaping up to be the hottest ever for the region.

Saturday was, in fact, the hottest Sept. 5 on record in Phoenix. The high of 115 degrees broke the record of 113 degrees set 75 years ago and was the second-hottest September day on record. The only day hotter was Sept. 1, 1950, when the mercury hit 116 degrees.

Friday was also a record, with 114 degrees registered at Sky Harbor, breaking the previous record for the date of 112 degrees set in 1945 and 2019. It stands as the third-hottest September day on record.

Sunday’s high temperature hit 111 degrees (at 2:30 p.m.), tying the previous high mark for the date set in 2013.

The past three days have extended the 2020 record for days this calendar year with temperatures at or above 110 degrees to 53 days. The previous mark was 33 days in 2011. Monday’s high temperature, forecast at 111 degrees, looks to put another notch on the belt.

Saturday also marked the 14th day of 115+ degrees for Phoenix this year, double the previous record of 7 days.

The record high for Sept. 7 (Monday) is 111, set in 1979.

Early Sunday morning, the weather service said Phoenix has had 19 record high temperatures and 18 record warm lows in 2020. And zero record lows or record low highs.

The latest date that 110 degrees was recorded in Phoenix was Sept. 19, in 2010.

The good news is that a strong system moving south out of Canada will bring much cooler temperatures and breezy conditions to the region on Wednesday and Thursday, before another bit of a warm-up for next weekend.

Here is the 7-day forecast from the weather service:

Sunday night: Clear, with a low around 79. West wind 5 to 10 mph becoming south southeast after midnight. Winds could gust as high as 20 mph.

Labor Day: Sunny and hot, with a high near 111. Breezy, with a light and variable wind becoming west 10 to 15 mph in the afternoon.

Monday night: Mostly clear, with a low around 79. West southwest wind 5 to 10 mph becoming south southeast after midnight.

Tuesday: Sunny, with a high near 107. Breezy, with a south wind 5 to 15 mph becoming west in the afternoon. Winds could gust as high as 20 mph.

Tuesday night: Mostly clear, with a low around 73. Breezy, with a west-northwest wind 10 to 15 mph becoming east northeast in the evening. Winds could gust as high as 20 mph.

Wednesday: Sunny, with a high near 97. East-northeast wind 5 to 10 mph, with gusts as high as 20 mph.

Wednesday night: Clear, with a low around 69. East wind 5 to 10 mph.

Thursday: Sunny, with a high near 98. Breezy, with an east wind 5 to 15 mph, with gusts as high as 20 mph.

Thursday night: Clear, with a low around 71. East wind around 5 mph.

Friday: Sunny, with a high near 101. East wind 5 to 10 mph.

Friday night: Clear, with a low around 71. North northeast wind around 5 mph becoming calm.

Saturday: Sunny, with a high near 103. East wind around 5 mph becoming northwest in the afternoon.