The leaves are beginning to turn. Frost covered much of the Hudson valley this morning. Fall has arrived in full. Today's high will stay in the upper 50s, almost ten degrees below normal, as a high pressure system slides across the region.

As the high departs a small low passing to the north may kick off a few showers overnight and into tomorrow morning. That is pretty unremarkable but when that low moves over the warm waters of the Gulf of Maine a little magic called coastal cyclogenesis will happen for the first time this season. That system won't affect the city much, tomorrow should be cloudy with a high around 60, but when cyclogenesis occurs off the Carolinas in a few months we'll call it a nor'easter.

The sun returns on Wednesday but it will be chilly. Look for a high in the mid 50s. Thursday and Friday are too depressing to think about. Let's just say rainy and cold and, if you're north and west of the city, perhaps a brief spritz of a more solid form of precipitation. The fall foliage should be brilliant this weekend in the Hudson Valley.