All foliage colors have peaked across much of the interior sections of New York and New England, but this weekend will offer plenty of dazzling color farther south. This barn and wooded hillside scene was photographed 4 miles west of State College, Pennsylvania, this week.
A storm strengthening off the Middle Atlantic coast will cause episodes of rain and cool gusty winds from Maryland to Maine. The heaviest rain today is focused on the Washington, D.C., to New York City area. Later tonight and tomorrow, the heaviest rain and strongest winds (gusts of 30-40 mph) should spread northeastward across New England. As the storm slowly departs, the weather will improve from southwest to northeast. This map shows the circulation around the storm as of 9 a.m. ET.
The reason for this is a growing and then stalling storm aloft. This map shows the predicted circulation around the storm on Wednesday evening, showing how the moisture could keep going round and round until the storm leaves.
This mornng, showers were moving across the lower Great Lakes region. A band of thunderstorms developed near Chicago before 6:30 a.m. CT and reached the southwest Michigan shoreline an hour later (8:30 a.m. ET). The following maps show the shower zone and Chicago area lightning.
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.