ABC News(NEW YORK) — Most of the nation has a quiet weekend ahead with no significant weather impacts in the forecast. A new system will bring some rain and cool conditions in the Northwest this weekend, while cool air also sinks into parts of the Midwest, Great Lakes and Northeast.

On Saturday, temperatures in the 30s are expected in the Northern Plains and into parts of the Great Lakes. This cool air moves to the east on Sunday and Monday, with temperatures dipping down into the 30s across the Great Lakes and Ohio Valley.

These temperatures are well below average, with a couple of record-low temperatures possible in the Great Lakes. The cooler air could also bring some scattered snow showers in the Ohio Valley and Great Lakes on Sunday morning.

However, a major pattern change is coming next week with dramatically different weather in the forecast.

Feeling like summer

The weather pattern will be changing dramatically over the next few days. As a result, severe weather is expected to ramp up significantly next week. This pattern will also bring the warmest air in over seven months to parts of the eastern U.S., with much of the East feeling like summer by the end of the week.

Early next week, a new system will move into the Northern Plains. The system will force cooler and drier air to clash with warm and moist air in the Central and Southern Plains. This weather pattern means there is the potential for a multiday significant severe weather event.

The first round of severe weather will begin on Monday with damaging winds, large hail and brief tornadoes likely from eastern South Dakota to western Texas, including Sioux Falls, South Dakota; Dodge City, Kansas; Amarillo, Texas; and Lubbock, Texas.

On Tuesday, the activity begins to move into the Central Plains, clashing with very warm and moist air. Widespread severe storms will develop from Texas to Kansas — including Oklahoma City, Oklahoma; Wichita, Kansas; and Kansas City, Missouri — on Tuesday and especially Wednesday.

Although particulars with the storm setup remain unknown, it appears increasingly likely that these storms could be robust and violent on Wednesday with strong tornadoes possible.

The storms will likely move into parts of the Ozarks by Thursday, but there is uncertainty on the magnitude of the impacts of the severe weather right now.

It is important to note that this is the time of year when strong and numerous tornadoes develop over the plains. Besides the severe weather outbreak just two weeks ago across the Gulf Coast, April has been very quiet in terms of tornadoes due to the sustained cool and dry air from the north.

For parts of the central and eastern U.S. — including New York, Boston and Philadelphia — it is finally time to get your shorts and T-shirts out and put the coats away.

A ridge of high pressure developing across the eastern U.S. means temperatures on Monday will be well into the upper 70s and 80s across much of the central United States. In the Northern Plains, 80-degree temperatures are 10 to 15 degrees above average.

On Tuesday, the warmth expands to the East Coast, with widespread upper 70s and 80s expected from Texas to New England. Temperatures in the Midwest to the Northeast will be nearly 10 to 15 degrees above average — including in Chicago, Philadelphia, New York City and Boston.

Another pulse of warm air heads toward the Northeast by the end of the week. Temperatures by the end of next week could be approaching 90 degrees across the entire Northeast. These forecast highs are nearly 20 to 25 degrees above average. The last time it was 90 degrees in New York was Sept. 24, 2017. For Boston, you have to go back to Aug. 22, 2017.

A factor that could hold temperatures down locally would be any sea or bay breezes that develop, since water temperatures remain quite cold.

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