Metro Detroit is in for another cold night, with frost and near-freezing temperatures possible early Tuesday morning before a wetter pattern arrives Tuesday afternoon and evening.

Alerts

A Freeze Warning will go into effect at midnight and remain in effect until 8 a.m. Tuesday for Sanilac, Lapeer, St. Clair, and Macomb counties, where temperatures could drop to 27 degrees.

A Frost Advisory will blanket the remainder of Southeast Michigan, including Genesee, Livingston, Oakland, Washtenaw, Wayne, Lenawee, and Monroe counties during the same time span.

The coldest temperatures are expected north and west of Detroit.

Even if your thermometer reads 35 or 36 degrees, frost can still form on grass, rooftops, decks, and vehicles.

That is because surfaces cool more quickly than the air several feet above the ground.

Under clear skies and light winds, heat escapes rapidly from the ground overnight through a process called radiational cooling.

Cold air also sinks and settles into lower spots, allowing temperatures near the surface to briefly reach freezing while official air temperatures remain a few degrees warmer.

That means the temperature at ground level where plants are located can be colder than the temperature reported by a standard thermometer mounted several feet above the surface.

Sensitive plants and vegetation could be damaged or killed by the cold.

How to protect plants

Gardeners are encouraged to protect tender plants overnight by covering them with lightweight fabric sheets, blankets or frost cloths.

Bringing potted plants indoors or into a garage can also help prevent damage. Experts recommend avoiding plastic coverings directly on plants because plastic can trap moisture and transfer cold temperatures to leaves.

Flowers, vegetables, herbs and newly planted annuals are especially vulnerable this time of year.

Tomatoes, peppers, basil, petunias and other warm season plants are among those most sensitive to freezing temperatures.

The chilly pattern will not last long.

Clouds increase Tuesday morning, followed by scattered showers developing during the afternoon.

Temperatures rebound into the upper 50s and lower 60s with a gusty south breeze developing during the day.

Rain becomes more widespread Tuesday evening and Tuesday night. A few thunderstorms and rumbles of thunder are also possible overnight as a stronger weather system moves through the Great Lakes.

Severe weather is not expected, but brief downpours, gusty winds and small hail cannot be ruled out in a few stronger storms Tuesday night.

Behind the system, cooler air returns Wednesday with highs mainly in the 50s to around 60 degrees and gusty west winds.

Sunshine and milder weather return later in the week, with temperatures climbing into the 60s Thursday and around 70 degrees Friday.

This weekend

By the weekend, Southeast Michigan will get a taste of early summer.

Temperatures are expected to surge into the upper 70s and lower 80s Saturday through Monday, although there will be occasional chances for showers during the weekend.

That includes Flower Day on Sunday at Eastern Market in Detroit, one of the city’s most beloved spring traditions.

Thousands of people are expected to visit the market to shop for flowers, plants, herbs and garden supplies as growers from across the region fill the sheds with color.

Right now, the forecast calls for warm temperatures near 80 degrees Sunday with a chance of scattered showers.

While it may not be a completely dry weekend, it will feel dramatically different compared to the frosty start to the week.

For now, though, gardeners across Southeast Michigan will want to focus on protecting sensitive plants from one more cold Michigan night.

Remember to share your weather and garden photos with Local 4 at MIPics.