Marietta, GA climate
Marietta has mild winters and warm summers, with plenty of rain. A typical July afternoon reaches 88°, a January night drops to 33°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Marietta feels like
Winter
Spring
Summer
Fall
Marietta weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 52° | 33° | 4.8" | 0.2" | 11 | 0 | 35° – 49° |
| February | 56° | 35° | 4.9" | 0.2" | 9 | 0 | 38° – 55° |
| March | 64° | 42° | 5.0" | 0.1" | 10 | 0 | 46° – 62° |
| April | 73° | 49° | 4.1" | 0 | 8 | 0 | 56° – 66° |
| May | 80° | 58° | 4.1" | 0 | 9 | 0 | 63° – 74° |
| June | 86° | 65° | 4.4" | 0 | 10 | 0 | 71° – 79° |
| July | 88° | 69° | 5.0" | 0 | 11 | 0 | 76° – 82° |
| August | 88° | 68° | 4.2" | 0 | 10 | 0 | 74° – 83° |
| September | 82° | 62° | 4.0" | 0 | 7 | 0 | 69° – 78° |
| October | 73° | 51° | 3.6" | 0 | 7 | 0 | 58° – 66° |
| November | 62° | 41° | 4.2" | 0 | 8 | 0 | 46° – 57° |
| December | 54° | 36° | 4.8" | 0 | 10 | 0 | 36° – 55° |
| Year | 72° | 51° | 53.1" | 0.5" | 109 | 0 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Marietta
Marietta gets 53 inches of rain and melted snow a year. July is the wettest month and October the driest. Rain or snow falls on about 109 days a year.
About 218 frost-free days a year
In half of years the last 32° night comes by April 2 and the first one by November 4. That leaves about 218 frost-free days for gardens, longer than 81% of U.S. towns.
Heating and cooling a home in Marietta
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Marietta, 64% of that work is heating and 36% is cooling.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Marietta and its neighbors
Marietta borders 2 towns with climate data. January nights across them vary by 0.1°. Fair Oaks has the coldest January nights (33°) and Smyrna the hottest July afternoons (89°). Marietta’s January low is 33° and its July high 88°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Marietta compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Marietta averaged 1.0° warmer than the 1900s. The biggest change is in December (+2.4°). The shift is smaller than in 66% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Marietta’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. December swings the most: between 1991 and 2020 its average temperature ranged from 36° to 55°. July is the most reliable, staying within 6°.
Common questions about Marietta’s climate
What is the coldest month in Marietta?
January, with a typical high of 52° and a low of 33°.
What is the hottest month in Marietta?
July, with a typical high of 88° and a low of 69°. About 55 days a year reach 90°.
How much snow does Marietta get?
Almost none. A normal year brings 0.5 inches.
When is the first frost in Marietta?
In half of years the first 32° night comes by November 4, and the last spring frost by April 2.
What is the rainiest month in Marietta?
July, with 5.0 inches of rain and melted snow. The year totals 53 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Marietta itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Atlanta 9nw, GA (9 mi, snow) and Dallas 7 Ne, GA (12 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.