More Tranquil Weather Today, Showers & T-Storms Return By Friday
Happy Wednesday, everyone! High pressure and upper-level ridging from the Great Lakes/Ohio Valley gradually builds into Northeast and Mid-Atlantic regions over the next couple days. This will allow for some more pleasant, warm and dry to continue today and much of Thursday. Then more unsettled weather will be returning with an increasing chance of showers and thunderstorms over the Northeast during Thursday night and Friday, as a frontal system moves through. But some improving weather is expected over the weekend. Read further for more forecast details through this weekend and a look at the weather for next week!
For today, strong subsidence aloft will support mostly sunny skies, with just some high cirrus and patchy clouds around this afternoon. West-northwest downslope winds will support high temperatures to reach upper 80s to around 90 over I-95 corridor this afternoon. While the interior locations will see highs more in lower to middle 80s with weak cold air advection aloft. Humidity will remain on the comfortable side. Then mostly clear skies and light winds are expected tonight, as the center of high pressure moves over the Northeast. This will support excellent conditions for radiational cooling, especially across the Interior. NYC and urban areas will drop into the mid-upper 60s. Many of the suburbs will drop into the upper 50s to lower 60s. Many of the Interior Valleys and Pine Barrens regions in the Northeast will fall the mid-upper 40s or lower to middle 50s.
NAM model temperatures over Northeast early Thursday morning
High pressure shifting offshore will support more onshore winds on Thursday. Light northeast winds during the morning will becoming southeasterly during the afternoon hours. With more onshore flow, high temperatures will be little cooler in the lower to middle 80s. Sunshine will dominate most of the day, as the axis of the upper-level ridge moves over more the Northeast. But some mid-high clouds will be increasing and thickening later in the afternoon and evening, as warm front and shortwave trough begins approaching from the west. Some scattered showers and thunderstorms may develop over parts of Interior New York and PA during afternoon hours and evening hours. The main threat with this activity will be heavy rainfall and lightning. Otherwise it will remain dry elsewhere with high temperatures will ranging from the upper 70s to lower 80s along the coast to middle 80s over inland areas.
Low pressure associated with the shortwave trough will track into the Western Great Lakes region and push the warm front through Northeast late Thursday night and Friday morning. Along with it, some scattered showers and isolated thunderstorms possible, during this time frame. But instability will be generally be weak or elevated, no severe weather is anticipated. Then cold front will come through Friday afternoon and night with more scattered showers and thunderstorms. More instability will support a threat for some isolated strong-severe thunderstorms over the Northeast. But the best forcing will be shortwave energy closer to the Great Lakes. So more organized or widespread severe weather is still not anticipated at this time. However, a weak secondary low forming along a warm front further south, may enhance more showers and thunderstorms that could into late Friday night and early Saturday morning. Tropical moisture surging up the coast, with high precipitable water values. So some thunderstorms could produce torrential downpours and localized flash flooding.
NAM model forecasting high precipitable water values and moderate instability and shear parts of the Northern Mid-Atlantic region during Friday evening.
Latest models have much of the I-95 corrider region still in the warm sector on Saturday. But the best shortwave forcing and dynamics will be over shifting northeast in Southeast Canada. So some improving weather still expected later Saturday. High temperatures could be in upper 80s to around 90 before another cold front comes through during late afternoon or early evening hours, mainly dry. More sunshine with some clouds is expected on Sunday as high pressure builds over the Northeast and Mid-Atlantic regions again. But some lift and instability with shortwave trough could trigger some few isolated showers are possible mainly over the Interior Northeast, during the afternoon hours. Temperatures will likely be closer to normal on Sunday as high pressure with a Canadian airmass moving into the Northeast and Mid-Atlantic regions.
Then more upper-level ridge builds over the Northeast and Mid-Atlantic region, ahead of an upper-level trough digging into the Great Lakes region on Monday and Tuesday. High pressure will be off the Mid-Atlantic and will support more southwest flow helping temperatures to rise above normal to perhaps upper 80s to near 90 again, with humidity increasing as well. Next frontal system that will be associated with the upper-level trough, will arrive by late Tuesday and Wednesday with some scattered showers and thunderstorms possible again over the Northeast and Mid-Atlantic region. Then more ridging over the Western US will support the upper-level trough over much the Eastern US with temperatures running near or below normal levels for the rest of next week. Stay tuned more premium forecast updates on the main dashboard and with more articles to come this week!