All Zones Late-AM Update: Cooler Today, More Showers Likely Thursday Night into Friday

Happy Wednesday! It will remain dry during the day today. But high pressure off the New England coast, will cause more southeast winds and allow for more clouds than sunshine over the region today. As a result, temperatures will be cooler than they were on Tuesday. Highs this afternoon will be in the 50s over most of the region. Some areas may, especially near the coast may struggle to get out 40s. Some inland areas could sneak up into low 60s with enough breaks of sunshine.

But skies will become mostly cloudy throughout the entire region this evening, as a warm front from the southwest begins approaching. Some scattered light rain showers or some drizzle could develop, this evening with low-level moisture increasing. But are more showers are likely overnight as weak cold front and mid-level disturbance from the northwest also moves through the region. Temperatures will likely remain steady in the 40s or 50s overnight with more cloud cover and showers overnight.

Showers will taper off by early tomorrow morning, as the weak cold front and mid-level disturbance passes through the region. But the some cloud cover will likely remain in the morning or midday hours, as the warm front will still be lifting slowly northward into the region. Some areas of patchy fog could also develop, as the front moves northward, with more warm-air advection occurring aloft.

There is some uncertainty to how much clearing occurs will occur by late in the day. But with more light southeasterly winds, just ahead the warm front, temperatures will likely rise at least into lower to middle 60s, away from the coast. Temperatures will likely remain cooler in the 50s with more marine influence over Long Island and along the New Jersey and Connecticut coasts. If skies clear enough, temperatures may continue to rise into the upper 60s or lower 70s. Best chance of this occurring will be over Western New Jersey and Southeast Pennsylvania.

Then as low pressure tracks well northwest of region, a secondary warm front will try to lift northward through region Thursday night and Friday. But another area of high pressure moving into far Southeast Canada, the warm front may stall south over Western or Central parts of New Jersey, This may support cooler marine airmass to back over areas to further north and east, including Northeast New Jersey and NYC. Temperatures may cool back down into the 40s and 50s Thursday night and Friday, north of the warm front. While south of the warm front, temperatures may warm back into 60s or 70s on Friday.

Best forcing will be closer to main low pressure and associated shortwave trough northwest of the region. But some more showers are likely a southerly low-level jet increases and enhances moisture convergence, along warm front over the region, especially late Thursday into Friday morning. There might be enough elevated instability for some isolated thunderstorms with heavy downpours and some lightning. But no significant or widespread weather hazards are anticipated with this system over the region.

Finally, a cold front, will come through later Friday afternoon and evening. But any more showers will be more widely scattered with less lift and instability along and ahead of this front. Skies will finally clear later Friday night and Saturday, as weak high pressure build into the Northeast, behind this storm system. Sunshine with northwest downslope winds on will help temperatures rise into back into the lower to middle 60s on Saturday afternoon.

However, an active pattern continues with the next storm system approaching form the southwest with increasing clouds likely by Saturday evening. Latest guidance continues to indicate a somewhat progressive solution with the upper-level trough associated with this storm system not amplifying enough or forming a cut-off low before reaching the East coast. This solution leads to less major impacts over the region.

But model guidance still shows some rainfall, possibly moderate to heavy at times late Saturday night into Sunday, with waves of moisture streaming northward out of the Gulf of Mexico and Atlantic. Then high pressure builds in with drier weather by Monday and Tuesday. Stay tuned for another zone forecast update this afternoon or evening with more information this storm system for late this weekend.