September weather for the Eastern US as a cool dome of air takes control Virginia to New York

Labor Day Sunshine & Cool Temperatures For Much of the Week Ahead,

Next Rain Risk Friday Night & Saturday

Labor Day is here and so is a large dome of high pressure that will be building into the Northeast US. This high in one form or another will be the player all week along. Offshore we have the old frontal boundary that extends southeastward into the coastal Carolinas down to Florida. This is where much of the shower and thunderstorm activity will be this week along with the Gulf Coast from Florida to Texas. This leaves us in partly to mostly sunny conditions today in Eastern Pennsylvania to Southern New England. There will be a nice northwest breeze, very low humidity, and highs mostly in the 70s.

Photo byNational Weather Service

Past Septembers as a whole have meant an extended summer season in the Northeast and Mid Atlantic but things are different this year thanks to a dominant northwest flow from Central Canada and into the Eastern US. This means dry days but it also means cool night. Skies will be clear tonight with lows in the 50s including the warmer urban areas and many inland areas will be in the 40s by Tuesday morning.

Photo byNational Weather Service

Tuesday we will see lots of sunshine from start to finish. High Temperatures will be mostly in the low to middle 70s for highs. We will continue to see a nice northwest breeze. Our surface high will be drifting into the Northeast and Middle Atlantic states slowly which will keep things nice and quiet.

Photo byNational Weather Service

Another cool night lies ahead for Tuesday night into Wednesday morning under clear skies. Lows again will be in the 50s with lots of 40s inland north and northwest of the coast. You won't have to go too far inland to see 40s. Wednesday is looking to be a sunny day. Temperatures may edge up to the middle and upper 70s as the high begins to slide off to the east and offshore.

Photo byTropical Tidbits

This high as so much dry air that it will take time for moisture to come back. The high is going to slide off the New England coast and not the Mid Atlantic coast. This makes a difference because instead of a southwest flow that warms things up and brings humidity, we will be in a onshore flow which will keep temperatures in check. Eventually we see another cold front coming east from the Great Lakes late in the week and another big dome of high pressure and cool air behind it. This set up will leave us in a decent spot for Thursday and Friday. The onshore flow might mean for some low clouds and fog developing during the nighttime and early morning hours but the dayside should be no worse than partly sunny for Thursday. After morning lows in the 50s to lower 60s, highs will be in the 70s to near 80 in the warmest locations. Friday will probably bring and increase in cloud cover but any showers hold off until Friday night. Saturday we will be ahead of a cold front with some showers and maybe a thunderstorm. Highs will be in the mid 70s to lower 80s but in comes another big dome of dry cool air for Sunday and for the start of next week!