Colleen Bready's forecast: Heat dome arrives in Manitoba

The heat dome is expanding into Manitoba on Wednesday.

It is an upper ridge of high pressure that will lock in excessively hot daytime highs and warm overnight lows over the next few days for most of the province.

Here in Winnipeg, the sky will be mainly clear today and tonight with light winds.

Several regions in central and northern Manitoba are now under a heat warning issued by Environment and Climate Change Canada.

The weather agency says more regions in the province will be placed under the warning today.

Over the next few days, temperatures across most of Manitoba will soar into the 30s during the day. There will be little relief at night with warm overnight lows in the mid to upper teens. Later this week, overnight lows in the south will only drop to the low 20s.

Humidex values are also forecast to climb to 40 or higher by Friday and Saturday.

Today could also produce severe thunderstorms, but not where you would expect. The greatest threat is in northern Manitoba where supercell thunderstorms could develop this afternoon. The main threats are 3-6 cm hail and strong wind gusts.

However, smoke spreading into the north from wildfires in B.C., Alberta and Saskatchewan could mitigate severe thunderstorm development there.