May 23: Thunderstorm Update

Discussion: A few showers and thunderstorms moved through parts of CNJ and SNJ already this morning and today. It looks like we have two more main waves of storms to deal between now and tomorrow morning.

The first wave is a Pre-Frontal Trough (PFT) that is currently approaching WNJ. It will hit NWNJ first (within next hour) and then NJ points further S shortly after. This is not the main event by any means despite the downpour, wind and lightning potential. This first wave is moving very fast and would be between now and about 5pm starting in NWNJ moving W to E and finishing in SENJ.

The main event is tonight. The PFT and other action that has already happened today is producing cloud debris which will inhibit diurnal destabilization ahead of the main event—one of the core ingredients in thunderstorm development. There still exists over 50 knots of vertical wind shear as well as a few other notable parameters however which is adequate to warrant the severe potential tonight.

I don’t think tonight will be a widespread linear thunderstorm segment that will hit all of NJ. I think it will be hit or miss in an isolated-to-scattered nature. Those hit could get hit hard with frequent lightning, damaging winds, hail and possibly a tornado. Those who miss will be saying “what thunderstorms?” Therefore this will be a mesoscale event that requires real-time monitoring of the best weather data possible.

As with all thunderstorms that cross NJ from W to E weakening is expected as the energy encounters marine layer air mass closer to the coast. NWNJ and WCNJ probably have the best chance to see severe conditions with frequent lightning. SENJ has the best chance to finish as just gusty rain with some lightning reducing in frequency. There is always the chance for severe thunderstorms all the way to the SENJ coast however and therefore it is best to play it safe. Hope for the fizzling gust front. Have a plan of shelter in case severe criteria makes it all the way to the coast.

In English: Showers and thunderstorms are possible over the next few hours followed by a break before the main thunderstorm event tonight. Tonight will be very hit-or-miss (isolated-to-scattered NOT widespread) especially for the coast later overnight. Thunderstorms are expected to come in hotter and stronger for WNJ than ENJ. Best to hope for the miss but prepare for the hit and that’s the most honest advise that anyone can walk away from a forecast with. Those hit should expect heavy downpours of rain, frequent lightning, gusty/damaging winds, hail and possibly a tornado. The main event storm period is between about 7pm and 3am overnight tonight. After that we clear for Friday and Saturday with unsettled conditions starting Sunday and especially into Monday. Have a great night and please be safe! JC

Jonathan Carr

Jonathan Carr (JC) is the founder and sole operator of Weather NJ, New Jersey’s largest independent weather reporting agency. Since 2010, Jonathan has provided weather safety and forecasting services for New Jersey and immediate surrounding areas through the web and social media. Originally branded as Severe NJ Weather (before 2014), Weather NJ is proud to bring you accurate and responsible discussions ahead of high-stakes weather scenarios that impact the garden state. All Weather. All New Jersey.™