Friday 10:40 a.m.
Chilly air is advancing into the Northeast this afternoon, and in many locations, tonight's chill will rival all-time records for the date. That's because the high pressure area marking the center of the chilly air mass will be right over the I95 corridor tomorrow morning, causing clear and calm conditions. Then, once the high moves to the east, a south to southwest flow of warmer air will become established. By Sunday afternoon, temperatures will be in the 60s throughout southern New England and 70 or higher farther south.
Strong thunderstorms from the middle of the country will head toward the western Great Lakes. The severe weather section at accuweather.com can be very helpful in explaining how these storms may affect you.
Tomorrow morning will be chilly in the Middle and North Atlantic states. Sam The Dog seems to like his early trip outside on cold mornings. I think it makes him appreciate the great usefulness of his fur coat.
The tropics have been more active recently. This map shows various entities that area being tracked and analyzed. Hurricane Gonzalo stands out clearly.
A couple of days ago, the storm entering the East had a stronger circulation than it does now. Here is the pressure analysis from earlier this morning. Several minor disturbance can be seen, and trough lines representing those have been sketched on the map. Note that there is little difference in temperature from western Pennsylvania to Wisconsin.
The rain band is only 100-200 miles wide, but it is moving slowly. This map shows its location at 10 a.m. today. Once the main rain band passes, it won't be quite as warm as it was when the rain started. However, by mid-October standard, it will still be mild.
On some days, there are so many "little things" that it is difficult to identify the players. Today, we see two systems dominating: the low pressure area on the left (west) and the high pressure area to the right (east). The cold front associated with the low pressure area is helping to support bands of rain.
One branch of the flow will go from Oregon and northern California eastward to the Plains, then it will go around the south side of the storm we have been talking about. A second branch of the flow will run from British Columbia northeastward to northern Hudson Bay. Cold air will be north of that current...which means it won't be anywhere near the eastern U.S. later this week.
It seems late in the season for tropical storm activity, but remember Sandy came late in October two years ago, causing heavy snow in the West Virginia and western Maryland mountains and disastrous effects from New Jersey to southern New England.