Unusually hot weather in the District will cause temperatures to spike nearly 10 degrees higher than average through Wednesday.
The short heat wave certainly doesn’t compare to the two-week stretch of temperatures higher than 95 at the beginning of the month, but it will still be enough to send people scrambling for air conditioning.
The mercury will get as high as the upper 90s on Wednesday, which forecasters say will be the hottest day of the week. Temperatures for Tuesday are forecast to be in the mid-90s, said Bryan Jackson, a meteorologist with the National Weather Service.
The heat index will be around 100 degrees Tuesday, and could be as high as 105 on Wednesday.
Temperatures are still a bit lower than those during the heat wave at the beginning of the month, which was caused by a high pressure system that trapped heat above the eastern half of the country. During that wave, temperatures peaked at 105 on July 7 and the heat index hit 110. A new all-time record for June was set at 104 degrees on June 29.
This summer is the sixth hottest on record, with an average high temperature of 89 degrees.
The hotter temperatures this summer have been caused by high pressure to the south or southwest of the mid-Atlantic, Mr. Jackson said.
“It’s a common summertime pattern, but it’s been particularly persistent this year,” he said.
This week’s toasty temperatures are no different, resulting from high pressure bringing air from the Deep South up to the mid-Atlantic region, Mr. Jackson said.
The typical temperature this time of year is 87 degrees, which the weather should return to by Friday.
“Heat like this doesn’t go away quietly,” Mr. Jackson said.
Thunderstorms cooling down the region are predicted to kick off Wednesday afternoon and last through Thursday night. The storms could be severe with potential for hail, wind and flash flooding, Mr. Jackson said.
No heat advisories have been issued for the coming week yet. Wednesday is the most likely day for an advisory, since the benchmark is a heat index of 105.
The District has already announced precautionary measures effective on Tuesday and Wednesday. The Department of Parks and Recreation extended hours for some pools. The Department of Public Works also announced that trash collection will begin an hour earlier than usual on those two days.