Why freeze warning only issued for the southern Miami Valley

Since the first day of spring, March 20, the days have become longer and the strength of the sun has increased.

This change in incoming solar radiation will directly impact the rise in our daily average temperatures.

Typically during this time of year, overnight lows fall to the lower 40s, but that doesn't mean some nights can't be cooler.

In fact, according to the National Weather Service, the average last date of 32 degree temperatures is around April 19, but have been recorded as late as May 21 for Dayton.

While we can see freezing temperatures into May, it's the warmer days that trigger the beginning of the growing season.

Areas south of I-70 generally start their growing season before our northern communities.

Because of this, on nights when temperatures drop close to freezing, the National Weather Service will begin to post freeze warnings.

Dependent upon how far into the growing season we are, there may be time when only the southern counties get placed under a warning.

As more vegetation is evident in northern counties, freeze warnings will then be issued if necessary.

There could be a few days to a couple weeks lag between growing seasons in the Miami Valley.

A few ways to keep your plants safe:

  • Bring plants indoors to protect them from the colder temperatures
  • Cover plants and bushes with sheets or burlap (not plastic) to trap heat from the soil, keeping the plant warmer through the night
  • Remove cover early in the morning when temperatures climb above freezing
  • Water plants to add moisture to the soil, this will help to insulate the plant's roots

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