Northern Suburbs: Sandy Springs, Roswell, Johns Creek, Alpharetta, Brookhaven, Dunwoody, Peachtree Corners, Milton, Woodstock, Canton, Duluth, Chamblee, Sugar Hill, Suwanee, Norcross, Buford, Holly Springs, Mountain Park (Gwinnett), Doraville, Ball Ground, Berkeley Lake, Nelson, Waleska, Mountain Park (Fulton/Cherokee), Rest Haven Eastern Suburbs: Stonecrest, Tucker, Redan, Lawrenceville, Decatur, Candler-McAfee, Snellville, North Druid Hills, Conyers, North Decatur, Belvedere Park, Clarkston, Lilburn, Scottdale, Panthersville, Gresham Park, Druid Hills, Dacula, Stone Mountain, Grayson, Avondale Estates, Lithonia, Lakeview Estates, Pine Lake, Milstead Southern Suburbs: South Fulton, East Point, Peachtree City, McDonough, Stockbridge, Union City, Forest Park, Fayetteville, Fairburn, Riverdale, College Park, Lovejoy, Locust Grove, Hampton, Irondale, Tyrone, Morrow, Conley, Hapeville, Palmetto, Jonesboro, Bonanza, Heron Bay, Chattahoochee Hills, Lake City, Brooks, Woolsey Western Suburbs: Marietta, Smyrna, Mableton, Douglasville, Kennesaw, Acworth, Lithia Springs, Powder Springs, Vinings, Fair Oaks, Austell, Fairplay, Kennesaw State University
Topography and geology The area sprawls across the low
foothills of the
Appalachian Mountains to the north and the
Piedmont to the south. The northern and some western suburbs tend to be higher and significantly more
hilly than the southern and eastern suburbs. The average elevation is around . The highest point in the immediate area is
Kennesaw Mountain at , followed by
Stone Mountain at ,
Sweat Mountain at , and
Little Kennesaw Mountain at . Others include
Blackjack Mountain,
Lost Mountain, Brushy Mountain,
Pine Mountain, and
Mount Wilkinson (
Vinings Mountain). Many of these play prominently in the various
battles of the
Atlanta campaign during the
American Civil War. If the further-north counties are included,
Bear Mountain is highest, followed by
Pine Log Mountain,
Sawnee Mountain, and Hanging Mountain, followed by the others listed above. Stone, Sweat, Bear, and Sawnee are all home to some of
the area's broadcast stations. The area's
subsoil is a dense clay soil, colored
rusty by the
iron oxide present in it. It becomes very
muddy and sticky when wet, and hard when dry, and
stains light-colored
carpets and
clothing easily. It also tends to have a low
pH, further aggravating gardeners. The fineness of it also means it is easily deposited into streams during heavy rains, creating
silt problems where it is exposed due to construction. This transported red soil can be seen downstream on the
riverbanks of south Georgia (where the native clay is white), and down to the
Florida panhandle (where the native
sand is also white).
Topsoil is present only in natural forest areas, created by the
decomposition of
leaf litter.
Earthquakes and fault lines An extinct
fault line called the Brevard Fault runs roughly parallel to the
Chattahoochee River, but as its last movements were apparently
prehistoric, it is considered extinct and not a threat to the region. Still, minor
earthquakes do rattle the area (and all of Georgia) occasionally.
One notable one was in April 2003 (magnitude 4.6) coming from the northwest, its
epicenter just across the state line in northeastern Alabama. While many people slept through the 5A.M. quake, it caused a minor panic in others completely unaware of what was happening. Similar earthquakes occur in this region called the
Eastern Tennessee seismic zone, often felt much more widely across the stronger
crust of eastern North America as compared to the west. Thus, the
1886 Charleston, South Carolina earthquake was also felt in Atlanta and throughout the Southeast. It caused damage as far as central Alabama and West Virginia. Two small earthquakes were also felt on the southeast side near
Eatonton in early April 2009. The
New Madrid seismic zone (near the Missouri-Tennessee borders) and the
seismic zone producing the 1886 magnitude 7.3 earthquake are still capable of producing moderate or major earthquakes, which the entire Atlanta area will feel moderately or even strongly.
Climate The Atlanta metro area has a
humid subtropical climate with four
seasons. Summer is the longest. January daily lows average from north to south, and highs range from , but often reach well above or below this average. There is an average annual snowfall of about , falling mostly from December through March, though there was snow north of the city on April 3, 1987. Snow flurries are actually common during the winter months when there is an especially deep trough in the jet stream. These events usually do not amount to more than a slight dusting and therefore go unrecognized in most weather summaries. Summers are long and consistently hot and humid. July mornings average and afternoons average , with slight breezes, and typically a 20–40% chance of afternoon
thunderstorms. During the summer afternoon thunderstorms, temperatures may suddenly drop to 70–77 degrees with locally heavy rainfall. Average annual rainfall is about . Late winter and early spring, as well as July, are the wettest. Fall, especially October, is the driest. From 1878 to 2011, the highest recorded temperatures at Atlanta were on three days in the extraordinarily hot July 1980, followed by that month and
during a heat wave in August 2007, the hottest month ever for the area. This was broken on the last day of June 2012, when the temperature reached , during a massive
heat wave that hit most of the country, with another 105 the next day tying the July record. The lowest recorded temperatures were and on January 20 and 21 of 1985, and on February 13, 1899, during severe cold snaps that went so far south they devastated the entire
citrus industry in
central Florida.
Hurricane Opal brought sustained
tropical storm conditions to the area one night in early October 1995, uprooting hundreds of
trees and causing widespread
power outages, after soaking the area with rain for two days prior. Since 1950, some metro counties have been hit more than 20 times by tornadoes. Cobb (26) and Fulton (22) are two of the highest in the state. The
Dunwoody tornado in early April 1998 was the worst
tornado to have struck the area. A
tornado struck downtown Atlanta in March 2008, causing a half-billion dollars in damage. The area experiences a
winter storm with significant
snowfall about once each year. This can be extremely irregular, with several consecutive years receiving no measurable snow. A
blizzard (see:
1993 Storm of the Century) caught much of the Southeast off-guard in 1993, dumping at the Atlanta airport on March 13, and much more than that in the suburbs to the north and west, as well as in the mountains. The only other recorded winter storm of comparable severity was the
Great Blizzard of 1899. The heaviest snow was in January 1940, when buried the city during its coldest month on record. The second-heaviest was in 1983, when a very late storm dumped on March 24.
Ice storms have occurred in the area. The well-remembered 1973 ice storm was brutal, as was the storm in 1982. The
2006–2008 Southeastern United States drought began with dry weather in 2006, and left area lakes very low. The drought began to abate significantly after the
2009 Atlanta floods, when some areas got up to of rain in a week, with half of that falling in just 24 hours near the end of the period. The
USGS calculated it to be a greater-than-
500-year flood.
Environment The area's prolific rains are drained by many different
streams and creeks. The main
basin is that of the
Chattahoochee River, running northeast to southwest. The further northwestern suburbs drain into the
Etowah River via the
Little River and
Lake Allatoona. The southern suburbs are drained by the
Flint River, and the east-southeastern ones by the
Oconee River and
Yellow River. By 2005 the metro area was using of water per day (about per person per day) from these rivers. This usage was reduced by more than 10% during the drought, but soared back up after watering restrictions were eased (and before the flooding ensued). The need for water is seen as a barrier to further growth in the area, but permanent measures for non-emergency
water conservation have never been put in place. The state legislature has refused to pass a requirement for
low-flow toilets to be installed in homes that are sold, bowing to
pressure from the
real estate sales industry. Disputes over water are becoming increasingly common, with both
Alabama and
Florida filing
lawsuits and threatening
injunctions to prevent Georgia from taking too much water, mostly for metro Atlanta.
South Carolina also threatened when a
pipeline east to the
Savannah River was mentioned even informally. The state has now been ordered by a judge to reduce withdrawals from the Chattahoochee south of Lanier to 1970s levels within three years (2012), something that would create an immediate emergency water shortage if it were actually enforced.
Flora The native
forest canopy is mainly
oak, redbud,
hickory,
poplar,
tuliptree,
pine, and
sweetgum, with
chestnut having been common decades before in what is now considered
oak-hickory forest.
Saw palmetto,
Sabal palmetto and
Trachycarpus fortunei have become common ornamentals as well. Traveling from the south, the metro area is generally the first area in which
autumn leaf color can be seen, due to the different trees growing at the higher elevation and
latitude.
Underneath, the
flowering dogwood is very common, the
black cherry are quite prolific, with
mulberry popping up sometimes as well.
Sourwood is also in its native range, and is easily identified by the fact that it turns fiery red in early October, much brighter and weeks earlier than most other trees (which usually peak in early November). Shrubby plants include
blackberry,
horsechestnut,
sumac, and sometimes
hawthorn.
Virginia creeper,
poison ivy, and
briar are common
vines. The
Confederate yellow daisy is a
wildflower native only to the area around Stone Mountain. Common garden plants include dogwood,
azalea,
hydrangea,
flowering cherry,
maples,
pin oak,
red-tip photinia,
holly,
juniper,
white pine,
magnolia,
Bradford pear,
forsythia,
liriope (
mondograss), and
English ivy.
Lawns can be either cool-season
grasses like
fescue and
rye, or warm-season like
zoysia and
bermudagrass which turn brown in late fall. A few
homeowners associations actually prohibit green grass in the winter. Native to the nearby mountains, maples are now one of the most common landscape trees for new homes and parking lots, giving their color in the fall instead of spring. When planted close to buildings (which provide shelter and radiate heat), they can retain some of their color into December, especially if November has been warm. Common
lawn weeds are
mock strawberry,
violet,
wild onion, and of course the ubiquitous
dandelion,
crabgrass, and
plantain. By far the most notorious
introduced species is
kudzu, a highly
invasive species from
Japan which climbs and smothers trees and shrubs. New effective herbicides as well as increased development of formerly rural areas has greatly reduced kudzu in the metro area (although still quite common elsewhere in Georgia). Wisteria planted decades ago by farmers in then-rural areas has become wild and is common in undeveloped forests. Some vines exceed 50 years of age and cover dozens of acres of forest, creating a dense, purple explosion each spring.
Japanese honeysuckle is extremely common, its fragrance an early summer delight. A common ornamental shrub, the
Chinese privet, has escaped to become the state's most invasive non-native plant species.
Fauna Among
mammals, the
eastern gray squirrel is by far the most ubiquitous, stealing
birdseed from the
bird feeders which many locals maintain.
Chipmunks and small brown
rabbits are common, but it is relatively rare to hear of them doing any damage.
Opossum,
raccoons,
foxes,
coyotes and
armadillos are frequently seen. Garden and meadow snakes are common; five venomous
pit viper snakes (
timber rattlesnake,
pygmy rattlesnake,
coral snake,
water moccasin and
copperhead) are indigenous, but reports of bites are rare. Many types of frogs, including tree frogs and bullfrogs, are easily heard in early summer, as are
cicadas in July and August.
Black bears occasionally wander down from the mountains, and
white-tailed deer are abundant; overpopulated in some areas. Homeowners in the outer suburbs are prone to landscaping damage due to scavenging deer. The most common
birds are the
brown thrasher (the GA
state bird),
American crow,
European (or common) starling,
American robin,
mourning dove,
house sparrow,
northern cardinal,
house finch,
Carolina chickadee,
tufted titmouse,
bluejay,
white-breasted nuthatch, eastern bluebird, mockingbird,
brown-headed nuthatch, and
Carolina wren. Birds of prey thrive in the area, with three varieties of hawks common near open fields in even the most populated areas. Falcons roost on skyscrapers in downtown Atlanta and can be regularly seen feasting on pigeons. The American kestrel is sometimes seen. Late in the year, three species of owls can be heard nightly in wooded areas. Various
woodpeckers can be seen in forested lots, including the
red-bellied woodpecker,
northern flicker (also known as the "yellow-shafted flicker"), and the
downy woodpecker. The red-headed woodpecker is common in open fields and on golf courses. The
American goldfinch is present mostly in winter, and the
ruby-throated hummingbird only in summer. ==Demographics==