The past week of Monday, June 17, 2024 saw extreme weather across the United States in the forms of record high temperatures in the Eastern US, record low temperatures in the Western US, and heavy precipitation in the Central US. We also saw the first Tropical Storm, Alberto, of the year affect southern Texas and northern Mexico. Let’s look at the weather pattern that caused the extreme weather, the records broken, and the forecast for the rest of June.

The biggest story was the Eastern US heat wave which brought record high temperatures and very high heat indexes to millions of people. The heat wave was associated with a strong high-pressure system while a strong low-pressure brought cold air and snow to the higher terrain in the Western US. This upper-level weather pattern was impressive during the week of June 17.

Records were broken throughout the week in the US. Check out the broken or nearly broken records from Monday, June 17 through Sunday, June 23.

Record Warmth

Daytime high temperature records were broken across the Eastern half of the US last week because of a strong high-pressure system. This high-pressure system caused temperatures to increase and stay above normal throughout the week, with the addition of high dew points creating very high heat indexes. This strong high-pressure created a heat wave, which is associated with above-normal temperatures for an extended period.

Records were broken throughout the week but the most widespread record high temperatures were broken on Thursday, June 20 and Saturday, June 22.

These temperatures do not consider the heat index, which is the feels-like temperature caused by high dew points. Heat indexes were in the 100s throughout the Eastern US. 

There were several areas of thunderstorms throughout the heat wave as well. Several days saw severe thunderstorms with strong winds, hail, and even a few tornadoes.

Record Cold

While the Eastern US was baking in the heat, the Western US saw an unusually cold air mass during the week of Monday, June 17. A strong low-pressure system moved into the Pacific Northwest, bringing cold temperatures and precipitation. Record low temperatures were broken with temperatures in the 20s and even lower! Several high-elevation mountain ranges saw light snow with snow accumulations of 2-12+ inches.

Records were broken throughout the week but the most widespread record low temperatures were broken on Tuesday, June 18 and Wednesday, June 19. The coldest temperature observed on Tuesday, June 18 was 12 degrees near Mackay, Idaho.

Snow fell throughout the Western US with impressive totals for mid-June. Check out the snowfall totals from Saturday, June 15 through Wednesday, June 19, and this OpenSnow article with more details.

Heavy Rain

While the two extreme air masses broke records in the Eastern and Western US, the Central US saw heavy precipitation. A round of storm systems tracked through the Upper Midwest and brought several days of heavy rain. This heavy rain brought flash floods and was associated with severe weather.

Below is a look at the observed precipitation from Monday, June 17 through Sunday, June 23.

Additionally, we had the first Tropical Storm of the year, Alberto, which impacted northern Mexico and southern Texas. Winds were sustained at 30-45mph along the coast, but the biggest impact was heavy rain of 3-15+ inches across the region. The heaviest rain over 15 inches fell in interior Mexico.

Forecast Remainder of June 

The week of Monday, June 24, 2024 will see active weather continue across the US.

• Wildfire season is beginning in the Western US with a couple of wildfires growing and transporting smoke.
• Above-normal temperatures will occur throughout the Central US with dangerous heat indexes likely. 
• Severe thunderstorms are likely through the Central US and some parts of the Eastern US.

Thanks for reading!

Zach Butler