A new record high has been set in Sarnia-Lambton but some relief from the heat is expected soon.
A record high of 34.4 C, 93.9 F, was recorded at Sarnia's airport late Tuesday afternoon. Environment Canada Warning Preparedness Meteorologist Geoff Coulson said the previous record was set in 1988 with 33.6 C, 92.4 F.
Coulson said the record for Wednesday is 33.9 C, 93 F, set in 1988 and the national weather agency is currently forecasting a high of 32 C, 90 F.
Environment Canada has weather records at Sarnia's airport dating back to 1968.
A heat warning was issued for most of southwestern Ontario on Monday. Cooler temperatures are expected to move in late Wednesday afternoon.
"That is going to usher in a much more comfortable brand of air for the day on Thursday but then we do start to see the temperatures starting to climb again for Friday and into Saturday," said Coulson. "Saturday, another day it could be very warm and humid as well."
However, Coulson said another heat warning is not expected to be issued for Saturday.
"At this point, it looks like Saturday will just be a one-day event," he said. "Another front is going to go through late Saturday into Sunday."
As short-term relief from the heat is expected into Thursday, Coulson said thunderstorms are not anticipated in southwestern Ontario.
Tuesday marked the first official start to summer, which is expected to be warmer than normal.