First comes the rain – then brace for extreme heat Hamilton

First comes the rain and thunder – then brace for the heat.

A special weather statement issued by Environment Canada for the Hamilton area is calling for potentially heavy thunderstorm Wednesday afternoon with amounts ranging from 30 to 50 mm with higher amounts possible in some areas.

The heaviest storms are expected Wednesday morning through midday.

Southwest wind gusts are expected to hit 20 km/h and go as as high as 40. High 22. Humidex 28. UV index 4 or moderate.

Showers are expected to tapper off after midnight then mainly cloudy with 30 per cent chance of showers into Thursday morning. High of 29 but with the humidex, that will feel like 34.

A persistent southwest flow is forecasted, bringing hot and humid air from the Gulf of Mexico. And it’s unclear when the heat is going to let up.

This will likely be the most significant heat event of the season so far, Environment Canada warns.

Beginning Friday or Saturday and continuing through the Canada Day long weekend, expected daytime highs are in the low to mid thirties with humidex values into the mid forties.

Overnight lows should only hit the low twenties, providing little or no relief from the heat, the weather agency said.

Wednesday night, showers are expected to tapper off after midnight.