September 11, 2017 Hurricane Irma Event

September 11, 2017
Hurricane Irma Event

The September 11, 2017 Hurricane Irma event in Georgia involved the remnants of Major Hurricane Irma (which made landfall in southwest Florida as a Category 3 on September 10), weakening to a tropical storm as it moved northward into southern Georgia early on Monday, September 11. The very large wind field brought widespread tropical storm-force conditions across much of the state through the day and into September 12 (when it degenerated to a remnant low over Alabama).

The primary impacts hit north, central, and southern Georgia, with the Atlanta metro and north Georgia (including areas like Nelson/Dacula) experiencing significant wind damage despite the center tracking farther west.

Major Hurricane Irma made landfall in southwest Florida on September 10, 2017. Irma moved northward through the day on September 10th, gradually losing intensity but continuing to bring widespread wind damage and heavy rainfall along its track. By the morning of Monday, September 11th, then-Tropical Storm Irma moved into Georgia with a very large wind field containing at least tropical storm force wind gusts (39+mph). These high winds lasted several hours across most of the state, which resulted in many thousands of downed trees and caused 1.5 million customers in Georgia to lose power. Given the extensive damage, power was not restored to many areas for several days. With generally dry conditions prior to Irma's arrival, flooding issues in this area were relatively minor, though portions of southern and coastal Georgia outside of the NWS Atlanta/Peachtree City forecast area experienced more significant flooding as well as coastal storm surge.

Key Highlights

Widespread sustained winds of 30-45 mph with gusts in the 50-65 mph range downed numerous trees and power lines across the area. Many trees fell onto homes and businesses, causing additional damage. Unfortunately, at least two people were killed in the north Georgia due to falling trees with several others sustaining injuries. Below are some of the notable wind reports across the area during Tropical Storm Irma.

Wind Impacts (Main Threat):
- Widespread sustained winds of 30-45 mph with gusts commonly 50-65 mph (isolated higher in spots); tropical storm-force gusts (39+ mph) lasted several hours statewide.
- Extensive tree falls (thousands downed, many large oaks/pines uprooted or snapped), power line damage, and structural issues (trees crushing homes, vehicles, roofs).
- Notable fatalities: At least 2 direct deaths in north Georgia — a 55-year-old man in Fulton County (crushed by tree falling on his home while sleeping) and a 67-year-old woman in Forsyth County (tree fell on her vehicle in driveway). Some reports note up to 3 total storm-related deaths in Georgia.
- Power outages: Nearly 1.5 million customers lost power (one of the largest in state history at the time); outages persisted for days in many areas, with prolonged restoration efforts.
- Blocked roads, downed lines on interstates/highways, and scattered structural damage (e.g., roofs partially torn, homes/businesses impacted by falling trees).
Rainfall and Flooding:
- Generally 3-6 inches across much of the state (higher in southeast/coastal areas, up to 8-10+ inches locally near the coast/Brunswick area).
- Flooding was relatively minor in north/central Georgia (dry antecedent conditions helped), but more significant flash flooding and river rises occurred in southern/coastal zones (outside primary NWS Atlanta area), with some storm surge inundation along the Georgia coast (e.g., St. Simons Island, Brunswick).
Tornado Activity:
- Very limited/no major confirmed tornadoes in Georgia from Irma (despite some tornado risk in feeder bands); focus remained on straight-line wind damage rather than spin-ups.
Other Impacts:
- Atlanta Hartsfield-Jackson Airport saw hundreds of flight cancellations.
- State of emergency declared statewide; evacuations ordered for coastal/low-lying areas east of I-95.
- No widespread catastrophic flooding statewide (unlike Florida's core impacts), but tree/wind damage was extensive and costly.
Context:
- Irma was one of the most powerful Atlantic hurricanes on record (peaked at Cat 5, long-lived), causing massive devastation in the Caribbean and Florida before inland weakening.
- In Georgia, the large size and fast forward speed spread wind threats far inland; this was a classic "rain/wind maker" for the Southeast despite lower intensity.
- Part of the active 2017 season (following Harvey); Georgia saw significant but not catastrophic effects compared to Florida.

Why No Tornadoes?

Despite the fact that much of the area was on the side of Irma typically favorable for tornadoes, no tornadoes were recorded across the state during Irma's passage. The primary reason for this lack of tornadoes was the fact that an unseasonably cool and stable air mass was in place across the area. In fact, high temperatures were only in the 60s that day, which set record cool high temperatures for September 11th for many locations. These cool temperatures eliminated any instability that would have supported tornado-producing tropical convection associated with Irma. (NWS)

Recovery focused on massive tree/power restoration (weeks in spots) and community cleanup. In north Georgia areas like Nelson/Dacula, tree falls and outages were among the biggest issues—typical for large tropical systems clipping the region!