Tuesday 9:45 a.m.
A southwesterly flow of warm, moist air ahead of a cold front is contributing to a band of rain and thunderstorms that stretches from the Ohio Valley into parts of the Middle and North Atlantic states. We expect some showers and thunderstorms to cross the I95 corridor from D.C. to Boston later today and this evening.
The cold front should slip south then stall from Virginia or Maryland to Kentucky tomorrow. With the front likely to make only limited progress, some additional showers may occur tomorrow from D.C. to New York City and on west. Most of New England should turn sunny.
In general, computer models suggest a low pressure area forms along the front in the Middle Atlantic states on Friday then slowly moves up along the coast this weekend. If that happens, it will be a damp weekend in the I95 corridor of the Northeast.
In contrast, most of the Great Lakes region looks like it will bask in sunshine with afternoon temperatures in Detroit and Chicago close to 70 and nights cooling to the 40s and 50s. The video has more.
In the longer range, the re-curving of the latest western Pacific typhoon may signal an upper air trough (and cool weather) in the Northeast in a week to 10 days.
Late September is not generally known for widespread thunderstorms, but this map shows near 50,000 lightning strokes in the period from 8 EDT last night until just after 8:30 EDT this morning.
It is freezing cold in the Northeast this morning, but this map shows that much more mellow mildness has reached the Plains.
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>: