Climate Summary for 2009

2009 Climate Summary for North and Central Georgia
January 1, 2010

2009 was definitely a year of weather anomalies for north and central Georgia. Excesses from the norm ranged from 5+ inch hail produced in super cells during a severe weather outbreak in mid-February to a record 100-year flood event on the Chattahoochee river in mid-late September.

After 3 consecutive years of drought, conditions in January hinted at more of the same was in store for the parched region. Rainfall deficits ranged from -1.99 inches in Athens to -3.66 inches in Macon, while above average monthly temperatures ranging from 1.0 degree in Athens and Columbus to 2.0 degrees in Macon compounded the problem. In fact, record warmth occurred on the 6th, when Columbus reached 75 F. In February, the severe weather season began early, with two severe thunderstorm events occurring on the 18th and 27-28th. However, precipitation totals were again below average in Athens (-0.72"), Atlanta (-0.98"), and Macon (-2.23"). The trend in temperature also remained intact with Athens (+1.5), Atlanta (+1.0), and Macon (+0.7 F) all recording positive departures from normal. However, record rainfall, 2.75 inches in Columbus on the last day of the month, along with the 5th wettest February 28th in Atlanta with 1.61 inches established a drought reversing trend for the next several months.

Right from the start, March set the tone for abundant precipitation totals. The 1st witnessed the first heavy snowfall in 7 years, with a daily and monthly record set in Columbus of 6.5". Athens too recorded 6.5 inches, a record for the date, but falling short of their March record of 8.7" set in 1983. Surprisingly, this heavy snow event stretching from Columbus to Athens was accompanied by thunderstorms through its duration. Two more heavy precipitation events during mid and late March contributed to monthly surpluses in all four cities. In fact, it was the 2nd wettest March on record in Columbus with 12.70 inches of precipitation. And although, not in the top 10, the 7.78" recorded in Macon for the month was nearly 3 inches above normal. However, with all the cloud cover and precipitation, temperatures averaged near or within a degree above normal for all four locations. The plentiful rainfall continued over the next two months, as April totals exceeded the average in all four cities. Departures from normal ranged from +1.12 inches in Athens to +2.69" in Columbus. On April 2, a drenching of 2.78 inches in Macon broke a 71 year old record for the date. Similarly, on the 13th, Columbus received a soaking of 2.33 inches which was the 2nd most for the date. Due to a couple of late polar outbreaks during early and mid-April, monthly average temperatures were below normal by 1.4 degrees in Columbus, and 0.9 of a degree in the capital city. Ample precipitation continued in May, as Atlanta, Columbus, and Macon all posted wetter than average totals. Departures from normal were +0.59, +1.48, and +2.75 inches, respectively. Temperatures on the other hand, moderated a bit in May. Although, Athens reached 90 F for the first time in 2009 on April 25, it wasn’t equaled again until the last day in May, when Macon and Columbus also recorded high temperatures of 90 degrees. This late May warmth contributed to monthly averages above normal by 1.4 degrees in both Athens and Macon.

Then, conditions really heated up in June, as all 4 cities recorded average monthly temperatures of more than 2 degrees above normal. High temperatures reached 90 F or above on 17 to 23 days among the 4 locations. In fact, the fifteen consecutive days (16th-30th) Atlanta reached at least 90 F was the longest string in a June since 1981. Uncharacteristically, this hot weather led to June being the warmest summer month in all 4 locations. During this heat wave, precipitation became quite scarce. So much so, that Atlanta recorded only 0.02 inches of rainfall during the final 18 days of the month. This resulted in all locations, except Columbus recording rainfall deficits ranging from 0.74 of an inch in Macon to 2.28 inches in Athens.

The drier than normal conditions continued through July as all 4 locations posted rainfall deficits. Both Athens and Macon recorded their driest month for the year, receiving only 1.33" and 2.14", respectively. Temperatures moderated though, as monthly averages were cooler than June by as much as 1.7 degrees in the capital city. In fact, Atlanta only reached 90 F or above on 8 days in July compared to 17 times in June. July also experience unusually cool weather from the 18th - 22nd. Incredibly, during a 3-day period, 11 record low temperatures were either tied or broken in the four cities. Athens set new record lows with 58 F and 60 F on the 19th and 20th, Macon with 58 F, 61 F and 56 F on the 19th, 20th and 21st, respectively, as well as Columbus with 62 F, 64 F, and 61 F. An excess of rainfall returned to parts of north and central Georgia in August, due in part to the remnants of Tropical Storm Claudette on the 16-17th. The capital city received 6.14 inches for the month, while Columbus recorded more than twice its monthly average with 8.26". Again, temperatures were generally on the moderate side, as Atlanta and Macon both recorded their exact August normal temperature. Columbus contributed with a -1.7 deg departure from normal, while Athens posted a modest 1.3 degrees above their average.

Rare weather occurrences for 2009, continued in grand fashion during September. A persistent low pressure system located over the lower Mississippi Valley brought a week with prolonged periods of heavy rain. This resulted in an 8-day period from the 14th through the 22nd, which produced many rainfall totals in excess of 10 inches across north and central GA, including 13.19 inches in NE Atlanta. The Epic flood which resulted, set or broke several high water marks in the local watersheds that dated back to 1919. This historic event saw the Sweetwater Creek Basin rise to the 500-year flood level. By the end of the month, it was the 3rd wettest September in Macon, the 4th wettest in Athens, and the 5th wettest in Atlanta. The abundant moisture, also contributed to September being the 3rd consecutive month with average temperatures near or close to normal.

A strengthening El Nino/Southern Oscillation (ENSO) warm episode in the tropical Pacific continued the very wet pattern across the southeastern U.S. in October. A series of four potent low pressure systems brought record rainfall again to north and central Georgia. One of these rain soaking systems, established new daily rainfall records in Atlanta and Athens on the 12th. A deluge of 3.84 inches in Athens and 2.50 inches in Atlanta, broke previous records of 2.70" (1994) and 1.34" (1994), respectively. On the 27th, another drenching produced a record 2.11" in Columbus, while Atlanta nearly equaled their previous record of 2.08 (1972) with 2.02". By the end of the month, both Athens and Atlanta had recorded their 2nd wettest October ever with 9.14" and 8.71", respectively. When combining the totals since September 1st, Athens and Macon saw their wettest September-October on record with 19.00"and 17.05", respectively. Temperature wise, October was cooler than average in all locations, except Macon. Departures from normal ranged from -1.8 degs in Atlanta to -1.1 degs in Athens to a +0.6 degs in Macon. A mid-October polar outbreak contributed to these cooler than normal temperatures. In fact, Athens and Macon dropped to near freezing on the 19th, breaking the old record low of 34 F (1948) in Athens with 33 F, while tying the record of 35 F in Macon, also set in ‘48.

Although, not as wet as the previous two months, November also received well above average rainfall. One storm in particular resulting from the remnants of Tropical Storm Ida on the 9th-11th produced most of the monthly precipitation. The daily total on the 10th of 4.05" in Atlanta, 3.07" in Athens, 5.44" in Columbus, and 2.53" in Macon were all new records, breaking the old records of 2.57" (1966), 1.43" (‘66), 1.26 (‘66), and 0.64 (1955), respectively. The resurgence of tropical air in mid-November helped push monthly temperatures above the average in Atlanta (+0.4 deg), Athens (+2.1 degs), and Macon (+0.5 deg), while Columbus recorded a departure from normal of -1.3 degrees.

As the El Nino continued to strengthen, a persistent cycle of low pressure systems once again became established in December. Four of these systems originating along the Texas Gulf coast, then tracking east-northeastward produced significant precipitation across northern and central Georgia in the range of 1 to 4 inches. The first storm system, produced record daily rainfall in Athens, Columbus, and Macon on the 2nd with 3.20", 3.63", and 1.69"measured, respectively. The 4th system of the month also achieved rainfall records on the 18th, when Atlanta received 1.89", breaking a 73 year old record by 0.33". Macon too set a new record for the date, receiving 1.51" which eclipsed the old record of 1.20" set in 1948.  All four cities had above normal rainfall for the year, with Columbus setting a record with 80.20".  Atlanta had its second wettest year on record and Macon came in third wettest since records were kept.