The longwave trough at 500 hPa is starting to move offshore and over the North Atlantic Ocean. There is a shortwave ridge behind it currently centered over the Great Lakes region which is associated with high pressure at the surface in the Midwest. This will result in clear skies and a more northerly flow for Stony Brook, bringing tonight’s low down to around 25F. High pressure will continue to build into Stony Brook on Sunday as the 500 hPa ridge moves eastward into Ontario, with flow becoming more northwesterly and the high reaching around 37F. This weather pattern will continue until Monday when another longwave trough and frontal system will begin to approach the area.