NJ weather: Big change from humid to comfy, big waves from Hurricane Lee

The Bottom Line

Since Labor Day, New Jerseyans have been chewing through high humidity and facing on-and-off thunderstorms and downpours. It has been a very summer-ish weather pattern, although not very September-ish.

Wednesday is a big transition day, as a slow-moving cold front first drives in rain, followed by a new air mass. Actually, the "drydown" will be much more prominent than the cooldown, with a sharp drop in humidity bringing much more comfortable conditions by the time you wake up Thursday morning.

Thursday will be a beautiful day, with a "fall feel" in the air.

And then there is one significant wrinkle later this week: Hurricane Lee. The powerful storm is already shooting big ocean waves toward the Jersey Shore. And coastal concerns are still the big headline for New Jersey.

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Wednesday: Still Humid

To start the day, we are getting soaked. Heavy rain and thunderstorms are actually running ahead of schedule — they arrived around 3 a.m. and are already moving out, as of this writing. If it is still pouring where you are, be aware there is a localized flooding concern. Some spots saw a quick inch or two of rainfall early Wednesday morning.

After mid-morning (the 9 a.m. hour), NJ's skies will dry out completely. We will see clouds breaking into sunshine through Wednesday afternoon. There is a chance for some popup showers and thunderstorms starting around mid-afternoon (3 p.m. on).

Most notably, it is still going to feel humid today. Dew points will slide backward into the 60s — not horrendous, but noticeable. High temperatures will reach about 80 degrees, give or take.

Beach-goers, please keep in mind the ocean is already very rough. Ocean wave heights will swell to about 7 feet Wednesday, even though Hurricane Lee is still 1,000 miles away.

The big transition will happen after sunset Wednesday evening. Humidity will drop significantly overnight and skies will clear. Both factors will yield our coolest night in two weeks, as thermometers bottom out around 60 degrees.

Thursday: Not Humid!

Thursday will be the start of a comfortable, mostly beautiful stretch of weather. "Humidity season" is about to come to an end, as I do not see another spike in dew points coming in the foreseeable future.

Skies will turn bright and sunny by mid-morning Thursday. And both our weather and air will be bone-dry.

High temperatures Thursday will reach the mid 70s. That is slightly below normal for mid-September, but still very comfortable.

I have decreased the wind speed from the "breezy" category, although I would not rule out some gusts to 20 mph. That wind will blow straight out of the north.

Friday & Saturday: On Lee's Western Edge

The forecast for Hurricane Lee has only shifted slightly westward in the last 24 hours. (Closer to the coast.)

Lee's forecast impacts for New Jersey have not changed, and will be most prominent from Friday to Saturday.

Here is the latest rundown of expected impacts, in decreasing severity:
—Big Waves... Beaches will be pounded by big waves, likely causing moderate to major erosion. (Not a good thing with nor'easter season right around the corner.) Ocean waves heights will already grow to 7 feet on Wednesday, peaking around 12 feet from Friday into Saturday.

—Coastal Flooding... Tidal guidance is starting to pick up on Friday's high tide cycles. And we are going to see at least minor category flooding along tidal waterways, starting Friday evening. Two feet of storm surge is enough to cause water inundation issues in "the usual spots" — those roadways and low-lying areas that "always" flood when there is a big coastal storm nearby. There is a chance flood levels will creep higher on Saturday — we will get a clearer view of that piece of the puzzle in the next 12 to 24 hours, so stay tuned.

—Wind... Friday will turn breezy, with potential gusts between 20 and 25 mph. As Lee's center makes its closest pass to New Jersey Saturday morning, those north-northwest gusts may climb to 30+ mph. Still nowhere near tropical storm or hurricane strength, but definitely noticeable.

—Clouds... Clouds will roll in Friday, staying over New Jersey through much of Saturday. Thickest cloud cover will be along the immediate coast, with thin cirrus clouds likely extending throughout New Jersey.

—Rain... A few models show a very limited shower chance on the backside of Lee's broad circulation Saturday morning. I don't buy the rain chance, given our dry atmosphere. But it is something we will watch as the forecast continues to evolve.

—Temperatures... Hurricane Lee's close fly-by will actually enhance our impending cooldown. I already mentioned the brisk north-northwest winds that will result from the storm. That will drive in even cooler, drier air than would have arrived without the storm. Temperatures on Friday will struggle to reach the lower 70s. We will do better on Saturday, back in the mid 70s.

Sunday & Beyond

By Sunday morning, Lee's low pressure will be rapidly pulling away, and our skies will clear back to sunshine. As winds become southwesterly, we will warm up again, pushing near 80 degrees by the afternoon.

Some model guidance paints some showers Sunday evening to early Monday morning, as a weak front arrives. I am not sold on the rainy forecast though, given our predominantly dry forecast.

Next week's weather looks tranquil and pleasant, with highs mainly in the 70s and continued low humidity. Our next threat of rain would not be until late next week, heading toward the Fall Equinox on Saturday.

Dan Zarrow is Chief Meteorologist for Townsquare Media New Jersey. Follow him on Facebook for the latest forecast and realtime weather updates.