Oh, the Humidity! Summer Sun and Storms Return to NJ Wednesday
The Bottom Line
Tuesday was a weird weather day. The northern 75 percent of New Jersey was shrouded in fog and clouds, keeping temperatures stuck in the 70s all day. A welcome respite from the heat. Although it was still incredibly humid.
Meanwhile, sunshine in South Jersey pushed thermometers to around 90 degrees. Also incredibly humid.
As fog and low clouds depart on Wednesday, skies will brighten. We return to more typical summertime weather, with both heat and humidity. And an almost-daily chance of thunderstorms.
When will the horrendous humidity substantially go away? Eh, maybe early next week. If we're lucky.
Most of New Jersey is starting the day still stuck in the clouds. Dense fog has enveloped most of the state - all but far northern and far southern New Jersey, really. Visibility is below a quarter-mile in spots, so don't be afraid to slow down as you drive through the clouds. A Dense Fog Advisory covers most of the state until 9 a.m.
It takes very specific conditions for long-lasting fog to develop. Relative humidity must be near 100%. Winds must be practically calm. And a stationary front draped over the middle of New Jersey has kept our air mass extra stagnant.
That front will lift north on Wednesday, allowing temperatures to rise and relative humidity levels to drop. That will lead to a drastic reduction in fog and low clouds through the mid to late morning hours.
By Wednesday afternoon, the entire state will return to seasonable, sultry, summer-ish weather. With breaks of sun and high humidity, temperatures will push to about 85 to 90 degrees. The "heat index" may reach as high as 95 - just below the "danger zone" in urban areas.
There is one additional "fly in the soup" in Wednesday's forecast: The return of thunderstorms. After about 4 or 5 p.m. through Wednesday evening, we will have to watch the western sky for a broken line of storms.
Not everyone in the state will experience a thunderstorm. In fact, several models paint a pretty tame scenario, with storms largely fizzling by the time they reach the coast. Still, if you do encounter a storm, locally heavy rainfall could lead to quick flooding or ponding issues. Gusty winds and dangerous cloud-to-ground lightning are possible too.
Clearing skies will take over after Midnight. Low temperatures will bottom out in the sticky lower 70s.
I had been hoping that Thursday would feature a subtle decrease in dew points, dropping humidity levels from "tropical" to "just sticky". Now I'm not so sure that will play out. Even if it does, you may not even notice.
Still, with mostly sunny skies and no rain in the forecast, Thursday does look like a decent mid-summer, mid-July day.
High temperatures will push into the upper 80s to around 90 degrees.
Definitely another "air conditioner day". Possibly the hottest day of the week.
Morning lows in the 70s. Afternoon highs in the lower 90s (away from the coast). In urbanized areas of northeast and southwest NJ, the heat index could climb into the upper 90s. Yuck.
A few thunderstorms may pop up Friday evening. But at the moment, they look isolated - few and far between.
Mid-July is, on average, New Jersey's hottest part of the year. So it's truly appropriate that we start the upcoming weekend with more sticky, steamy weather.
Thermometers will likely surge to 90 or better for most of the state by lunchtime Saturday, with increasing clouds. Humidity looks incredibly uncomfortable.
And then a slow-moving front will lead to some unsettled weather. I think we face two or three waves of scattered rain, between Saturday afternoon and Sunday night. According to the latest model guidance, the wettest, stormiest periods look to be Saturday evening and Sunday afternoon - however that timeline is subject to change.
Because of the rain and clouds around on Sunday, high temperatures across the state will probably end up closer to 80 degrees. Notably below normal for this time of year.
The Extended Forecast
There are two scenarios that could play out for early next week. On the one hand, if that slow-moving front stalls completely, another area of low pressure could lead an extended period of rain on Monday. On the other hand, if that front makes a clean pass by Monday morning, we will finally get a taste of drier air. As a sworn enemy of thick humidity, you probably know which solution I would prefer.
Don't worry heat fans, we're far from done with the "dog days of summer" heat and humidity. Long-range models show a return to excessive (if not dangerous) conditions by late July.