It’s rare to start April in such a perfect way with warm and dry conditions.
High pressure is repositioning off the coast, which will produce strong warm air advection throughout the northern Mid Atlantic. A weakening cold front is over the central Great Lakes this morning that will enhance the warm air advection through tonight which will keep much of the region rather warm. High temperatures will rise into the 70’s and potentially lower 80’s even along the coast, however the southwesterly wind will keep Long Island cooler with highs in the 60’s and 70’s due to the influence of the Atlantic ocean.
The cold front will drop south and west over the Hudson Valley, Connecticut, and the immediate coast tomorrow morning with slightly cooler conditions and scattered showers. However, the cold front will have less of an impact over the Philadelphia metropolitan area with continued warm conditions.
The cold front will be driven north and east on Tuesday night which will place the entire northern Mid Atlantic in the warm sector by Wednesday afternoon with clear skies and very warm temperatures. In fact, high temperatures throughout the northern Mid Atlantic will likely rise into the 70’s and lower 80’s, however there is likely to be cooler conditions over Long Island due to a marine influence.
Warm conditions are expected to continue through Thursday afternoon ahead of a strong cold front, keeping high temperatures in the 70’s and 80’s once again. The cold front is going to move slowly through the Philadelphia and New York City metropolitan area on Thursday night into Friday morning with showers and thunderstorms. The one feature I’m concerned about is at 850 MB. Note the strong thermal gradient ahead of the cold front at this level. A strong 850 MB LLJ will be developing along the New Jersey coast that will likely enhance the threat of strong to severe thunderstorms along the coast. These thunderstorms will have the potential to produce strong wind gusts, heavy downpours, and frequent lightning.
Once the cold front passes, high pressure will attempt to build into the Philadelphia metropolitan area from theTennessee Valley. A cold front boundary will set up over the Hudson Valley down through Long Island. This boundary will produce a significant thermal gradient over the region, leading to a wide range of high temperatures for this weekend. Note the trough at 500 MB to the right. A negative NAO pattern will be in place which a ridge builds over the Gulf Coast due to a MJO in the La Nina phase. This type of pattern will support very warm temperatures in the 70’s and potentially 80’s over the Philadelphia Metropolitan area and much of western/southern New Jersey. However, the New York City metropolitan area and eastern New Jersey will be under the influence of a marine air mass as a low pressure system and cold front produces an easterly to northeasterly wind. By Sunday evening however, the trough will start to lift north and east, allowing for warm conditions to push into the entire northern Mid Atlantic as a result.
For the best analysis and coverage of New Jersey weather, trust in NY NJ PA Weather! Do you need an edge in getting the most detailed analysis on how weather conditions will impact your traveling, boating and fishing, or energy needs? Then you need NY NJ PA Weather Premium Membership!