A large swatch of showers and storms moving toward north Georgia from the southwest is expected to dump heavy rain across metro Atlanta on Tuesday.

A flood watch has been posted for all but the far northern suburbs of metro Atlanta.

The watch was issued for areas of the state south of a line from Carrollton to Cumming to Homer, beginning at 7 a.m. Monday and continuing through Tuesday evening.

The National Weather Service said rainfall totals of 1.5 inches or more are possible across metro Atlanta, with 2.5 to 3.5 inches possible south of a line from Columbus to Macon.

That much rainfall would make this month the wettest February on record in Macon. So far this month, Macon has recorded 10.81 inches of rain; the February record is 12.04 inches, according to the Weather Service.

To the west in Columbus, the 10.50 inches of February rain recorded through Sunday has already eclipsed the record for the month of 9.41 inches, set in 1961, and that city’s all-time record for rainfall in any month of 13.62 inches, set in December 2009, is in danger of falling.

Atlanta’s rainfall total for the month of 4.90 inches is well below the February record of 15.82 inches set in 1883.

Channel 2 Action News meteorologist David Chandley said the rain should continue throughout much of the day on Tuesday.

Sunny skies are forecast for Wednesday through Friday, with cooler temperatures expected by the end of the week, Chandley said.

“Colder weather will start spilling in here later in the week,” he said.

Highs will be in the low 50s Monday, upper 50s Tuesday, mid-50s Wednesday, and in the upper 40s Thursday and Friday. Overnight lows will start the week in the mid-40s, but cool to the mid-30s by Friday.

Meanwhile, a downed tree caused a series of explosions that caught two homes on fire on Patterson Avenue in southeast Atlanta on Monday, Channel 2. Strong winds blew the tree down onto power lines and cut the gas line. Sparks from the power lines ignited the gas at the first home. That home caught fire and then winds blew the flames next door, Channel 2 reported.

In a second incident, trees fell on two parked cars on Victoria Place in Lithonia. No injuries were reported, according to Channel 2.