The #1 Sign Your Region Is About to Get Its First Hard Freeze

Change is famously the name of the game for fall. Each year brings the chance to catch stunning foliage as temperatures begin to dip before winter kicks off. But depending on where you live, it can be difficult to gauge exactly when truly frigid weather will arrive for the first time—which is especially trying if you’re worried about your garden or sensitive plants. So, what’s the most obvious sign your region is about to get its first hard freeze? Here’s what you need to look for as we march further into fall.

RELATED: 3 Regions Where October Temperatures Will Be Warmer Than Normal.

What’s the difference between a hard freeze and frost?

Fall is the time of year when frost warnings begin to pop back up in the weather forecast as a warning to gardeners and farmers that some plants or crops could get damaged. But that chilly-looking glaze you might see early in the morning isn’t the same as a hard freeze.

According to the National Weather Service (NWS), frost is the lowest of the three levels of approaching cold weather that occurs when solid surface temperatures dip below an area’s current dew point. Typically, air temperature needs to be around 33 to 36 degrees Fahrenheit, accompanied by a light breeze that’s 8 mph or less, for this frozen dew to form.

The next level of cold is a freeze, which happens when temperatures hit and fall below 28 degrees Fahrenheit for at least a few hours. This timeframe allows for susceptible plants to get damaged, as well as standing water to begin to ice over and wet surfaces to become slick.

A hard freeze occurs when temperatures drop to 28 degrees Fahrenheit or lower for a few hours or more. On top of damaging any remaining seasonal plants or foliage, this can also prove problematic for plumbing and irrigation systems, especially if they are not properly winterized.

How can you tell the first hard freeze is coming?

Of course, truly cold weather will arrive earlier for some areas depending on their local climate. But while the first signs of a hard freeze can change from year to year, there are some warning signs that you might be in store for one.

Even if you’re confident you won’t feel truly brisk temperatures for a few more weeks, it’s important to stay on top of regional forecasts for any approaching cold fronts, according to FOX Weather. Changing patterns can sometimes put chillier air masses on a trajectory with some areas well before they’re typically expected.

However, a stubborn high-pressure system in the right place can have the opposite effect, essentially becoming a shield against approaching frigid air. This can sometimes lead to an extended warm autumn when conditions don’t change.

RELATED: 4 Regions Where Fall Foliage Will Peak This Month.

These areas see the first hard freezes.

Anyone concerned about their outdoor plants or home’s utilities is likely accustomed to the annual return of colder weather. And if you’re hoping to get prepared in time, historical data can help provide a decent estimate of when those dates might arrive.

According to FOX Weather, some of the earliest hard freezes hit the continental U.S. as early as September. This area includes most of Montana, Wyoming, Idaho, Colorado, and eastern Oregon and Washington.

By the middle of the month, northern Midwestern and Plains States along the Canadian border also become susceptible, including North Dakota and the northern parts of Minnesota, Illinois, and Michigan. Northern New England and parts of New York also tend to see a freeze before the end of September, too.

October brings a new set of regions to the mix, with the early part of the month typically freezing the central Plains States and Midwest for the first time (across South Dakota, Iowa, southern Minnesota, southern Wisconsin, and northern Illinois, specifically), as well as southern New England and much of New York State.

By the time Halloween rolls around, hard freezes will likely have crept into areas just to the south of this. This runs from New Mexico through northern Texas and Missouri into Illinois, Indiana, Ohio, Pennsylvania, New Jersey, West Virginia, Kentucky, eastern Tennessee, western Virginia, and the western ridge of North Carolina.

Some regions will get their first hard freeze after October.

Areas further to the south may not even see the mercury drop below 28 degrees for a hard freeze until November. By the first half of the month, though, many more regions are historically at risk, including the Southeast, with much of Texas, Oklahoma, Arkansas, Mississippi, Alabama, northern Georgia, South Carolina, and eastern North Carolina historically affected. Large portions of California also come into play at this point.

The latest regions for hard freezes fall almost exclusively in the far southern reaches of the U.S., with lower portions of the Gulf States typically experiencing them for the first time during the second half of November. The deepest parts of southern Texas, Louisiana, and Florida may not even see a deep freeze until December or later—that is, if one even comes at all that year.