A relatively mild winter has one last trick up its sleeve as an unusually chilly airmass has descended from the Arctic onto the eastern half of the country. This brought Central Park in New York City only its second May 9 snow on record (first was in 1977) and has helped send numerous low temperatures to record levels all the way into Alabama and Mississippi.

April 13, 2020 will join April 16, 2011 and March 15, 2008 as days that will live on in local weather infamy. Some people lost their lives today — at least five fatalities were reported in Hampton County from the supercell depicted above. Others in places like Walterboro, Summerville, and Moncks Corner suffered serious damage to their homes or lost them entirely. It was a thankfully rare day that we hope to not see again for a good long while.

Unfortunately, we’ll be needing to spend this Easter evening getting ready for a round of strong storms tomorrow morning. The severe weather threat for Monday is coming into focus, and there’s not been much change to the previous thinking: A line of strong to severe thunderstorms will push through the area during the morning hours. These thunderstorms will be moving into an atmosphere that is favorable for strong, damaging wind gusts (70 MPH possible, according to the National Weather Service), a few tornadoes (one or two of which could be fairly potent), and large hail.

What’s clear about Monday is that, at some point, there will be a squall line with strong thunderstorms coming through the area. These storms will be capable of producing wind damage and could spawn a tornado or two along the leading edge of the line.

The degree to which this threat will materialize is going to be highly dependent on timing, and that’s where it gets tricky — but I’ll do my best to demystify it.