Today's video includes a time-lapse movie filled with cumulus clouds then presents a forecast for this week and hints about next weekend. The weekend was cooler than average in the major cities and coastal resorts from Maryland to Maine. The next few days will be warmer, but before any kind of heat wave can get established, another cold front will cross the Great Lakes and Northeast.
Bertha, just east of the Bahamas, had winds approaching hurricane force as the storm moved northward early this morning. As shown on this map, all computer model tracks show the storm staying well east of the U.S mainland.
Winds aloft are coming from Canada, but later (as shown on the map) this week will come from the Southwest states. That should promote a major, though temporary, warmup in the Middle and North Atlantic states.
Lake-effect snow hit Chicago this morning. This happens when cold winds at low cloud height are from the northeast. When the flow is from the west or northwest, the Michigan and/or Indiana snow belts come alive. These maps show the setup from this morning.
This map shows a low pressure center along a cold front that will cross the Eastern states today. From southern Pennsylvania southward, a few thunderstorms can develop this afternoon and evening, but everyone in the Middle and North Atlantic state should get some rain.
One way of displaying a forecast is by using a meteogram. Items like temperature, wind and precipitation are distributed across a chart so you can see what is supposed to happen and when. This cart is a meteogram for New York City. Three details are highlighted.
Thunderstorms broke out last night ahead of the warm front that will bring milder air to the Northeast on Thursday. Hundreds of lightning strokes occurred from Nebraska and Missouri into western Illinois. This picture shows a shaft of lightning about a mile from my home a couple of years ago.
Video: all the excitement of watching paint dry. This six-hour time lapse from Saturday, March 21, shows a parade of clouds overhead and the progressive melting of snow that fell heavily in central Pennsylvania the day before.