July 19: Heat Wave Detected

High pressure currently has control of the region but the heat and humidity are expected to return. High pressure is anti-cyclonic, which in the northern hemisphere spins clockwise (opposite of a low pressure system). So when high pressure approaches from the W, we are introduced to dry northerly flow from Canada. That’s what has kept today more pleasant which should spill into at least some of tomorrow. Once the center of the high pressure is to our E, we are then subject to humid/tropical southerly flow (the W side of the clockwise spinning air mass). That’s what should set up by Friday. With me?

Once the high pressure is over the Atlantic Ocean this weekend, low pressure in Canada will contribute to a general SW flow of warmer temperatures with higher humidity (tropical air mass tap) over New Jersey.  At the surface, temperatures are expected to easily break 90 degrees Friday through Monday. Dew point temperatures will ultimately dictate the real-feel. Above 65 is noticeable. Above 70 is rough. Above 75 is pretty much unbearable. Tuesday could be the day of relief, assuming the modeled cold front pushes through. Common sense says that could come with storms, especially since it will be plowing into such an unstable soupy air mass.  Let’s get through the weekend first.

In English: We’re currently warm/hot and less humid for a short period. You might feel some humidity start to creep in tomorrow but definitely by Thursday. Friday through Monday should then be 4 days in a row of 90+ temperatures with elevated levels of humidity. Heat indices should push into the triple digits so please stay hydrated and cool if you can. 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, social media, and app spaces. 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.™