Friday 9 a.m.
A slow-moving front moving southeast from the Great Lakes is triggering showers and thunderstorms, but it also ushers in drier air once it passes. Heavy rain has hit the area from south-central and interior southeastern New York into Connecticut. Later this afternoon, places in the New York City to Washington, D.C., corridor should be subjected to locally flooding showers and thunderstorms (that can also deliver pockets of damaging wind).
Next, the question is how far south the dry air will go. The computer models have been inconsistent on this all week. Last night's runs suggested that Boston and New York City will have plenty of sunshine both days of the weekend. The area from D.C. south into the Carolinas will have the chance of showers and thunderstorms, while places in between like York, Lancaster and Philadelphia, Pa., probably get sunshine but face a close call situation because showers will be so close to the south. This video has more.
This morning, heavy showers and thunderstorms caused flash flooding from extreme northwestern New Jersey across to western Connecticut. This radar picture highlights the big difference between the places with rain and those without it as of midmorning. The picture will change this afternoon.
Extensive precipitation straddles both sides of the cold front that was moving through central New York and central Pennsylvania as of mid morning. This radar shows the distribution of rain and snow; some temperatures are added.
The cold front approaching the East shows up quite well in this pressure analysis. Several temperatures are plotted to give you a sense for how much the temperature changes behind the cold front. At Chicago, it went from 60 at 4 a.m. to 39 at 5:19, a 21-degree drop in little more than an hour.
Temperatures on Sunday and Monday will range from the 60s in parts of New England to near 80 in Maryland and Virginia. However, a strong cold front will then trigger and perhaps a few thunderstorms as it ushers in air that will be 30-40 degrees colder than it will be ahead of the cold front.
During the early morning hours of April 15, there will be a total lunar eclipse visible across North America. This eclipse is the start of a <em>tetrad</em>, a series of four total lunar eclipses over a two-year period. The totality begins at 3:07 a.m. ET, 2:07 a.m. CT, etc.
Severe Weather Awareness Week activities are conducted by National Weather Service offices nationwide at various times during the spring. There is a lot of information for everyone (from children to seniors) available online. You can start <a href="http://www.ready.gov/kids/know-the-facts">here</a>:
However, after the warmup, another cold front will move through the Great Lakes and Northeast with at least some rain. This map contains the forecast for Sunday evening.