The stage is set this morning for a stormy start to July as a slow moving yet powerful Polar cold front inches east from the Northern Plains and the first Tropical Depression of the season off the Florida coast inches northward towards the North Carolina coast. The combination of these features will transport a tropical air mass into New Jersey that will also lead to the development of widespread showers and thunderstorms for tomorrow and Thursday.
Hazy, hot and humid conditions can be expected today as southwesterly winds take hold throughout New Jersey. An isolated shower or thunderstorm will be possible this afternoon due to a few mid level disturbances. These thunderstorms will be capable of very heavy downpours, frequent lightning, and wind gusts over 40 mph. The main weather story today, aside from the potential first Tropical Storm of the season by this afternoon, will be the heat with high temperatures in the upper 80's to lower 90's. The combination of dew points in the 70's will translate to a heat index in the mid to upper 90's this afternoon.
As the cold front inches closer to the region tonight, the threat for showers and thunderstorms will increase with isolated to widely scattered showers and thunderstorms a threat. Fog will also be a concern to the high levels of moisture in the atmosphere. Winds will be from the southwest at 5 to 15 mph. Temperatures will fall into the lower to mid 70's for lows.
Tomorrow, the showers and thunderstorms increase in coverage throughout the region. By this point, tropical depression one should be Tropical Storm Arthur and will be located around the coastal waters of Georgia and South Carolina. Some of the moisture from Arthur will lift into New Jersey at the mid levels which will enhance thunderstorms that develop in the afternoon. The thunderstorms will have more coverage area as the cold front will also be closer to the region over western Pennsylvania. The thunderstorms will feature very heavy downpours, frequent lightning, and wind gusts over 40 mph. The primary concern with these thunderstorms will be localized flash flooding, urban flooding, and visibility falling below 2 miles. Winds will be from the southwest at 5 to 15 mph, increasing to 10 to 20 mph. Temperatures will rise into the upper 80's to lower 90's and will feel like the mid to upper 90's in areas that do not have rainfall.
As Tropical Storm Arthur lifts northward towards the North Carolina coastal waters, the cold front will start to drive through New Jersey on Thursday. Tropical moisture will be drawn northward as the two systems interact leading to widespread showers and thunderstorms that will feature very heavy downpours as the primary threat. Wind gusts will exceed 50 mph in some thunderstorms, however flash and urban flooding will be the primary impacts from these thunderstorms along with poor visibility. The cold front will be slow to exit and will not be off the New Jersey coast until Friday morning which will mean showers will linger into the morning of Fourth of July. Winds will veer from the southwest to northwest at 10 to 20 mph as the cold front inches eastward. Low temperatures will range from the lower to mid 70's. High temperatures in the upper 80's to lower 90's.
The cold front will force what is left of Tropical Storm Arthur out into the Atlantic Ocean and well east of the New Jersey coast. Tropical Storm Arthur will not have a direct impact on New Jersey, however expect a choppy ocean with a strong rip tide a threat at the shore. Skies will clear from west to east on Friday with clear skies in time for the evening of the Fourth of July. Winds will be from the northwest at 10 to 20 mph, decreasing to 5 to 15 mph in the evening. Temperatures will rise into the upper 70's to lower 80's for highs with very low humidity.
High pressure will be in complete control for Saturday on through Monday with seasonal temperatures and very low humidity. Clear skies to scattered cloud cover can be expected through the weekend. Low temperatures will range from the lower to mid 60's along the coast and upper 50's to lower 60's over the interior. High temperatures will range from the lower to mid 80's along the immediate coast and mid 80's throughout the rest of New Jersey.