Here is when to expect NJ’s last frost, freeze, and snow of the season

OK, I know this subject may seem a little ridiculous, as New Jersey stares down its third day in a row of record-breaking 80+ degree temperatures.

But let me remind you of a very important fact: It is NOT summer yet!

April is, on average, New Jersey's 6th coolest, 4th driest, and 5th snowiest month of the year. Truly the definition of "middle of the road" and "shoulder season". But it's not normal to be this hot at this point of the season. And it also does frost, freeze, and snow regularly in the month of April.

As you know, this year's weather has been wild so far. January and February were snowy and incredibly cold. And then Mother Nature flipped the switch to periods of wonderfully warm and dry weather through late March and April so far.

Now we are staring down our next cooldown, which will send thermometers 30+ degrees colder over the coming days. That is going to be a huge, noticeable difference as we transition from t-shirts and shorts back to jackets and sweaters.

The Forecast

Could it really still snow in New Jersey this season? Sure. But as you might guess, substantial accumulations are highly unlikely. My rule of thumb is "big snow" becomes difficult after the first day of spring — the ground is warming, the ocean is warming, and the sun angle is rising.

It would take quite a storm to produce substantial snowfall this late in the game. But snowflakes (i.e. flurries) are certainly not impossible — some models have hinted at that possibility for next week.

The trickier question: Is New Jersey done with frosts and freezes for the 2025-2026 winter season? I don't think so. It looks like morning low temperatures will dip into the 20s and 30s across at least inland New Jersey next week (Monday/Tuesday), raising alarm bells that the growing season has not started yet for a majority of the state. (For the record, these may not even be the last occurrences of frost for the season.)

Of course, the general rule of thumb is to not plant your garden until about Mother's Day Weekend, in May, to be safe. So this timeline should not be much of a surprise.

Frost/Freeze Statistics

A freeze occurs when the low temperature at a given weather station falls at or below 32 degrees Fahrenheit. It doesn't matter how far below or for how long — if the thermometer hits 32, it counts as a freeze.

Here are the earliest "last freezes" ever recorded at selected weather stations around New Jersey:
—Sussex... April 16
—Newark... March 11
—New Brunswick... March 29
—Long Branch... March 21
—Trenton... March 24
—Atlantic City... March 30
—MIllville... March 27

And here are the latest "last freezes" recorded at those same stations:
—Sussex... May 22
—Newark... May 3
—New Brunswick... May 14
—Long Branch... May 11
—Trenton... May 10
—Atlantic City... May 21
—MIllville... May 21

Perhaps more useful is the average "last freeze," which gives a general idea of when overnight freezes become less and less likely:
—Sussex... May 4
—Newark... April 8
—New Brunswick... April 17
—Long Branch... April 13
—Trenton... April 10
—Atlantic City... April 21
—MIllville... April 21

Note: There are some issues with the length of record and missing data at some of these stations. But you can get the general gist that on average, we look for the last freeze in non-northwestern New Jersey right around mid-April.

A frost is more difficult to define. As cold air pools within the lowest few inches of the atmosphere — at ground level — ice crystals can form on grass, levels, etc. that we know as frost. This does not require subfreezing temperatures. We generally start looking for patchy frost to form under calm conditions with temperatures under about 37 degrees.

So here are the dates of the average "last 37-degree temperature" a.k.a. average "last frost" across the Garden State:
—Sussex... May 17
—Newark... April 22
—New Brunswick... May 5
—Long Branch... April 28
—Trenton... April 30
—Atlantic City... May 6
—MIllville... May 4

So again, as the calendar page turns to May, cold frosty mornings become less and less frequent and more and more unusual. Let the growing season begin!

Dan Zarrow is Chief Meteorologist for Townsquare Media New Jersey. Check out Dan's weather blog or follow him on Facebook for your latest weather forecast updates.