PITTSBURGH – Sunday marks the third and final day of a deadly multiday severe weather outbreak that spawned violent tornadoes, a dust storm and even blizzard conditions that left more than 30 people dead across the U.S.

At least 23 people have been killed as a result of the severe weather and tornadoes, with Missouri appearing to have been the hardest hit as officials there confirmed at least 12 deaths. Deaths have also been reported in Mississippi, Arkansas and Alabama.

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And in the central and southern Plains, a dust storm dropped visibility to nearly zero in portions of Texas, Oklahoma and Kansas on Friday. Officials said eight people were killed in a multi-vehicle pileup on Interstate 70 near the Kansas-Colorado state line.

Officials in Texas said four people were killed in multiple crashes – two in Palmer County and two in Gray County due to the high winds and low visibility from blowing dirt and dust.

Severe weather threat upgraded for Northeast on Sunday

Sunday’s severe weather threat stretches from the Southeast to the mid-Atlantic and Northeast.

Thunderstorms and wind caused air travel delays at airports up and down the East Coast on Sunday, with weather-related ground delays in Orlando, Tampa, Washington, D.C. and Philadelphia.

Hurricane-force winds were recorded in Pennsylvania and Ohio. Arnold Palmer Regional Airport in Latrobe, Pennsylvania recorded an 89-mph wind gust, according to the National Weather Service in Pittsburgh. A 76-mph wind gust was recorded earlier on Sunday at Zanesville Municipal Airport in central Ohio.

Power outages skyrocketed in Pennsylvania, with more than 135,000 customers without power by late Sunday afternoon. Thousands of outages were also reported across Ohio, West Virginia, Virginia and North Carolina. 

In all, more than 64 million people from Florida to New York state are at risk of severe weather on Sunday, including communities along the heavily traveled Interstate 95 corridor.

However, NOAA’s Storm Prediction Center (SPC) has placed more than 4.5 million people in parts of western and central Pennsylvania and southwestern New York in a level 3 out of 5 risk on its severe thunderstorm risk scale. This includes Pittsburgh and Erie, Pennsylvania.

Meanwhile, in the Southeast, a Tornado Watch has been issued for portions of Florida, Georgia, South Carolina and North Carolina until Sunday afternoon.

Other Tornado Watches were issued farther north in portions of Pennsylvania, West Virginia, Virginia and Maryland, which will also remain in effect through Sunday evening. 

Due to the damaging wind threat, a Severe Thunderstorm Watch is in place for western New York, including Buffalo and Rochester, through Sunday afternoon.

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The worst of the weather is expected in a swath that stretches from northern Florida northward to portions of the interior Northeast.

Cities inside this zone include Jacksonville in Florida, Savannah in Georgia, Charleston in South Carolina, Charlotte and Raleigh in North Carolina, Cleveland in Ohio, Pittsburgh in Pennsylvania and Buffalo in New York.

Damaging wind gusts will be the biggest threat with any severe storms that develop, but tornadoes are also possible.