A November Tornado Watch Covered 10.4 Million People Around Philadelphia

November is not tornado season in the Mid-Atlantic, which is part of why Thursday got people's attention. At 12:50 p.m. Eastern, the National Weather Service's Storm Prediction Center issued Tornado Watch 705 for a wide band of the Philadelphia region, in effect until 7 p.m.

The watch covered 20 counties: eight in Pennsylvania, including Berks, Bucks, Chester, Delaware, Lehigh, Montgomery, Northampton and Philadelphia; eleven in New Jersey; and northern Delaware. The cities inside the box included Philadelphia, Allentown, Trenton, Atlantic City and Wilmington. The Storm Prediction Center's exposure figures for the watch area were 10,380,513 people, 2,517 schools and 180 hospitals.

A watch is not a warning. It means the ingredients are present: on Thursday, the Center said a few tornadoes were possible, along with scattered hail up to ping-pong size, as large as an inch and a half, and isolated wind gusts to 70 mph. The region sat in a Level 2 of 5, slight risk, area for severe storms.

Warnings followed the watch through the afternoon, as they're supposed to. Severe thunderstorm warnings went up for parts of the region with hail of about an inch and a quarter and 60 mph gusts observed or indicated on radar, and flash flood warnings covered Philadelphia and Delaware County in Pennsylvania, Camden, Gloucester and Salem counties in New Jersey, and New Castle County in Delaware into the early evening. Rainfall ran from about half an inch to an inch and a quarter north of the city, with less in Philadelphia itself.

While the warnings ran, the Mount Holly office's page turned into a reporting channel of its own. Residents posted hail reports ranging from pea size to ping-pong size in Wilmington and Newark, Delaware, and accounts of wind damage to trees in Bear, Delaware, and the office answered professionally, asking people for photos and locations it could use to verify what the storms had actually done.

Across the harbor, a separate tornado warning briefly covered Queens, New York, in the early afternoon, for a storm tracked over Rockaway Beach. The local forecast office for the watch area is the National Weather Service office in Mount Holly, New Jersey, which fields Philadelphia's weather.

The watch expired at 7 p.m. as scheduled. What Thursday leaves behind is the calendar oddity: a mid-November afternoon on which more than ten million people in three states were told to be ready to take shelter from tornadoes, and a storm line that spent the day behaving like it belonged in spring.