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(CNN) -- A drastic change is coming, as a strong cold front will bring the first dose of autumn over the weekend and send temperatures down to 19°C.

The cooling is good news for millions of people in the south who have endured a brutally hot summer and a scorching start to autumn.

Relief from the heat will reach as far as the Gulf Coast. States like Louisiana, which this year has suffered the hottest summer in its history, will have below-normal afternoon temperatures for the first time since spring.

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The change will begin in parts of the Plains and Midwest, which have been enduring record heat in October since Saturday. Dozens of daily temperature records have fallen there, and some cities in Minnesota and Michigan have broken all October temperature records.

While the most brutal heat will soon come to an end in the north-central U.S., summer-like heat is starting to arrive in the Northeast. Temperatures of 5.5 to 8 degrees Celsius above normal October levels will be common until Thursday in the Great Lakes and Northeast.

It won't last long. The coldest air of the season will arrive later this week and give way to conditions not felt since early May in the northern U.S.


Where temperatures will drop dramatically

Starting Wednesday, two cold fronts will extend across the central U.S. and eastward Friday and the weekend.

Maximum temperatures from the Great Lakes to New York could drop to 19C by the weekend. Decreases of 10 °C will be more widespread.

The first cold front will bring relief to north-central U.S. states between Wednesday and Thursday. Places like Minneapolis, where record temperatures of up to 32.2°C were reached on Sunday, may not exceed 15°C on Wednesday.

The second cold front will be much more powerful and introduce the first truly autumnal air push of the season into the central and eastern U.S. Cold Canadian air will move south as the cold front crosses the eastern two-thirds of the continental U.S. from Thursday through Sunday.

Places like Detroit and Cleveland, which will reach 26.6C on Wednesday, will not exceed 10C on Sunday. In Philadelphia and New York it will reach 26°C at least until Wednesday, but on Sunday the maximum temperatures will not reach 15°C.

Maximum temperatures for Sunday.

Nighttime minimum temperatures will also drop behind these fronts.

Minimum temperatures will range from -1 to 10 degrees Celsius in the north-central U.S. and Midwest on Saturday morning, and in the Northeast on Sunday morning.

The first frosts of the season are possible in some northern states, such as North Dakota, Minnesota and Wisconsin, as temperatures drop below freezing.

The autumn cold will remain at the beginning of the month, especially in the eastern United States. According to the Climate Prediction Center, below-average temperatures are likely to be recorded from the Gulf Coast to the Northeast, at least until the middle of next week.

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Rains and storms will accompany the fronts

The drastic cooling won't be the only noticeable weather change this week. The clash between cold, autumnal air and moist, summery air will create stormy weather.

The threat of storms Wednesday will extend from the southern Plains to the Midwest. Some storms could turn strong Wednesday afternoon, mostly in Texas and Oklahoma.

Rainfall from these storms is badly needed in Texas, where 80% of the state is suffering from at least moderate drought, according to the US Drought Monitor. From Tuesday through Wednesday, 19 to 38 mm of rain could fall across much of the state, with higher amounts possible in areas affected by multiple storms.

Rain and storms will continue to move slowly eastward and affect parts of the eastern U.S. on Thursday and Friday, while wet weather will continue in the Midwest.

Periods of heavy rain are possible in the northeast over the weekend. Any heavy rainfall could pose a problem for parts of the region submerged underwater by flooding triggered by last week's rains.