Already on 28. March, Mkweather informed about forecasted and very long heatwave in North America in April 2021 /https://mkweather.com/extreme-heatwave-will-shift-from-mexico-to-greenland-the-first-hot-times-in-the-usa-and-canada-between-3-12-april// and this forecast was confirmed on 1. April /https://mkweather.com/big-heatwave-for-north-america-extreme//.
It´s 9. April and we should look at extreme high temperatures and temperature records across the USA and Canada from data available / published by meteorologists and climatologists on Twitter.
On Thursday, 8. April 2021, the first +40°C / 104°F in the USA was measured in Falcon Lake, southern Texas. Maximum temperature reached +40,6°C / 105°F.
Extremely warm air has shifted about southern Ontario, too, in Snarnia, +28,1°C / 82.6°F was measured, what is the highest temperature in Canada in 2021 so far and very close to provincial all-time record for the first April decade.
Extremely hot was in Rocky Mountains too - Pueblo in Colorado reported tropical +30°C / 86°F or Lamar, Colorado, +30,6°C / 87°F on Sunday, 4. April 2021 /https://www.outtherecolorado.com/news/132-year-old-temperature-record-falls-in-colorado-as-sweltering-heat-slams-state/article_58507e7a-9630-11eb-ac14-4314c8662e88.html/, with overcoming of 132-year old temperature records.
Twin Cities in Minnesota reported record +28,3°C / 83°F on Monday, 5. April 2021 and people should enjoy summer-like temperatures in early April.
According to coolwx map tool, temperature records have shifted during last 7 days (between 2.-9. April) from Rocky Mountains and southern USA above Great Lakes region and Northeast.
Northeastern USA should expect extremely weather at the weekend, eastern Canada until 15. April, yet, but above Central USA, the next severe coldwave is around 16. April forecasted.
If cold air above Midwest will be late next workweek collide with warmer air masses from south and east, tornado risk will increase again.