N.J. weather: Severe thunderstorm threat in forecast for Wednesday as heat surges

After a one-day reprieve from a week-long heat wave on Monday, the heat ramps up again for New Jersey on Tuesday ahead of an uncomfortably hot day Wednesday with heat indexes topping 100 degrees and a threat of severe thunderstorms.

Temperatures on Tuesday will be in the upper 80s and low 90s, but humidity levels will be lower so conditions won’t be as stifling as expected on Wednesday, forecasters say.

Expect a mild Tuesday night with lows dipping into the low-to-mid 70s. There’s also a slight chance of isolated showers across North Jersey, but it won’t likely amount to much.

Conditions on Wednesday will be considerably more volatile. High temperatures will soar into the low-to-mid 90s with the humidity making it feel like it’s about 100 degrees.

That sets the stage for strong late-day thunderstorms that pack gusty winds and the threat of localized flooding.

“Chances for scattered storms still look to begin by the afternoon, especially over northern and western area,” the weather service said in its Tuesday morning forecast discussion. More widespread thunderstorms are likely later in the evening.

All of New Jersey is under a “slight” risk of severe weather — level 2 on the weather service’s 1 to 5 scale.

A heat advisory will be in effect from 9 a.m. to 9 p.m. Wednesday for Somerset, Middlesex, Monmouth, Mercer, Gloucester, Camden, Burlington and Ocean counties. The advisory doesn’t apply to coastal areas of Monmouth as some relief can be found along the Jersey Shore where temperatures will top out in the 80s.

Some rain could linger into Thursday morning.

Both Thursday and Friday should be sunny and warm with highs in the 80s. Neither day will be overly humid.

Early indications are that there will be unsettled conditions this weekend with chances of rain and thunderstorms both days. Higher levels of humidity will also return.

“Not expecting a total washout though as most areas, even those that see storms, should be precipitation free the majority of the time this weekend,” the weather service said.

Current weather radar