Friday 10 a.m.
It is very warm from the Middle Atlantic states to the Ohio Valley today. While cooling will come to the Ohio Valley early next week, there will be a pronounced cooldown from Maine to Michigan to Maryland. There is a danger of a frost or freeze in much of that area Monday night and/or Tuesday night. Such an event is quite common at the end of March, but this year the effects on vegetation could be more severe because growth has progressed much further than usual. The video shows why the cooldown should occur.
Thunderstorms were common yesterday and last night as a large low pressure area lumbered eastward from the Plains. This map shows the lightning stroke pattern from 8 a.m. EDT yesterday to just before daybreak today.
A cold front that will cross the Northeast and Middle Atlantic states this afternoon and evening will trigger showers and, in some places, a thunderstorm. Once the front is offshore, a high pressure area from the Midwest will take over for the weekend.
This map shows the high pressure area that is promoting cool, dry weather in the Northeast today. The low pressure area on the left side of the map is associated with a cold front that will send showers eastward tomorrow.
With fine weather likely on most of the days ahead through early next week, leaf viewing will be a cool experience for many, especially in areas highlighted on this map showing the typical progression of peak fall colors:
This map is a forecast of the upper air flow early on Saturday, Oct. 16. It shows a mild to warm pattern for the Great Lakes and Northeast. The second map is for two weeks from today. Northern snow showers, anyone?
...with almost 16 inches of rain in Myrtle Beach, South Carolina, and more than 20 inches around Charleston. You don't find amounts like that anywhere in the historic record for this area. This picture shows the radar-estimated rainfall over South Carolina between Friday afternoon and mid morning today:
This map shows where Hurricane Joaquin was just before 8 a.m. ET. You can also see the stripe of clouds centered just of the Middle and North Atlantic coasts.