Pattern Change Coming: Hottest Time of the Year May Not Be Hot in the Midwest and East

Chris Dolce
Published: July 15, 2018

July is the hottest time of the year in the Midwest and Northeast, but the weather pattern as we head into the second half of the month may not deliver on those scorching temperatures thanks to a pattern change.

(MORE: July is the Hottest Time of the Year For Many)

In the near-term, hot and humid conditions will continue in parts of the Great Lakes, Ohio Valley and Northeast for the start of this week. Record-breaking high temperatures are not anticipated in most areas, but it will be muggy.

But not for long. A cold front will slice through the Midwest on Monday and then across the Northeast by Tuesday. That front should not only knock temperatures down, but it will also reduce humidity.

A cold front will push through the Midwest and Northeast Monday into Tuesday.

Chicago will see humid conditions and highs in the upper 80s early week. By Tuesday, highs are likely to retreat slightly below average into the upper 70s or lower 80s as drier air filters in.

A similar retreat in temperatures and humidity can be expected this week in Cincinnati, Detroit and Pittsburgh.

Drier air will reach the Interstate 95 corridor of the Northeast by Wednesday with temperatures returning close to average for this time of year.

(MAPS: Daily Forecast Temperatures)

Forecast Highs

This weather pattern with temperatures fairly mild for mid-July will likely persist well into the end of this week and next weekend.

High pressure is expected to build over the western states as a southward dip in the jet stream sets up over the Midwest, Great Lakes and Northeast, according to the long-term forecast guidance.

This means the door will be open for this mild weather pattern to stay in place at least across the Midwest and Great Lakes into late week and possibly beyond. That said, parts of those regions may encounter showers and thunderstorms late this week into next weekend.

Southward dip in the jet stream will keep heat out of the Midwest and parts of the Northeast late week.

The latest 6- to 10-day temperature outlook (July 20 to 24) from NOAA's Climate Prediction Center reflects this weather pattern by showing the greatest chance of below-average temperatures in the Midwest and South.

There is still some uncertainty in the details of this longer-term forecast: how long the heat relief sticks around and the exact areas that will experience it.

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