In this file photo from June, Kris Nay gets an earful from Donna Gomes as she ambushes him with a hose during the weekly car wash for the Church on the Street, at JPR Gasco, 3002 S. Sixth Ave. Tucson marked 39 days of temperatures of 100 degrees or higher Tuesday.

KELLY PRESNELL / ARIZONA DAILY STAR/File

Tucson hit 100 degrees at 2:39 p.m. Tuesday — tying the streak of 39 days of 100 degrees or higher, says the National Weather Service.

"We barely touched 100 degrees — tying the 39 days that were hit in 2005 and 1987," said Ken Drozd, a meteorologist with the National Weather Service.

The official readings are taken from instruments at the Tucson International Airport.

Wednesday's high is forecast at 98 degrees "so we may not break the record," Drozd said.

"Thunderstorms are expected Tuesday night around the Tucson metropolitan area, and that will produce clouds that may inhibit the heating on Wednesday," said Drozd.

He said with moisture in the air it is hard for the temperatures to rise. 

Tuesday's dew point was in the 60s and Wednesday's is expected to be the same, said Drozd.