A rather impressive mid and upper level trough is developing through the Mid Atlantic and Northeast States today, with a surface low pressure developing off the Mid-Atlantic coast. An inverted trough, extending northwestward from this surface low, is aiding in the development of very heavy rain along much of the area coasts including New Jersey and New York. Places to the northwest and interior have been able to escape the heaviest rain. But the low level jet will continue to support this heavy rain through the morning hours.
Later today, this rain will begin to swing southwest and wrap closer to the surface low. The low level winds which are currently moving in from the southeast (onshore) will shift to a more northeasterly direction and the inverted trough will swing southward, with the best lift for precipitation shifting away from the area. Still, showers and some thunderstorms will be possible throughout the day as the upper level low moves overhead and the surface low continues to develop.
Regional radar imagery this morning paints the picture quite well. It isn’t hard to see where the inverted trough is setup, or where the best moisture is pooling to the northwest. Embedded thunderstorms with rotation have remained offshore so far today, but we’re carefully monitoring to see if they’ll make a push toward the area beaches. So far, so good as the best forcing has kept them seaward.
As mentioned above, the threat for showers will continue today, but we do expect the steady/heavy rain to begin to wane and shift southward after lunchtime. Localized flooding will remain likely, especially near the coast. And regardless of where you are, we suggest bringing a jacket and an umbrella along. If you’re traveling, expect delays.
Stay tuned for updates throughout today. If you have the time, we suggest following us on Twitter (@nymetrowx). There, we provide up to the minute information and images.