Marginal instability and a weak cold front combined to produce scattered thunderstorms across north Georgia during the afternoon. Moderate mid-level lapse rates helped to produce an isolated report of large hail in the Atlanta metropolitan area.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS FFC wrote it up.
Marginal instability and a weak cold front combined to produce scattered thunderstorms across north Georgia during the afternoon. Moderate mid-level lapse rates helped to produce an isolated report of large hail in the Atlanta metropolitan area.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Atlanta, GA wrote its last area forecast discussion before the first event at Apr 18, 12:49 PM EST, 1 hour 16 minutes earlier.
Area Forecast Discussion National Weather Service Peachtree City GA 149 PM EDT Tue Apr 18 2017 .PREV DISCUSSION... /issued 1057 AM EDT Tue Apr 18 2017/ UPDATE... Continue to try to solve todays weather riddles made more difficult by a complex pattern that is not all that common. Basically we have an approaching shortwave with an advancing wedge front and conditional instability in place. By themselves these components are quite common and easy to discern but put together and there are quite a few unknowns today. What we do know is instability is building along the Atlanta metro and thinking this will still be the area of best development initially today. However...with storm motion back to the NE...activity that forms near Atlanta will shift quickly back to the mountains by this evening. Overall pops capture scenario very well and only limited changes planned. Deese PREV DISCUSSION... /issued 732 AM EDT Tue Apr 18 2017/ PREV DISCUSSION... /Issued 355 AM EDT Tue Apr 18 2017/ SHORT TERM /Today through Wednesday/... Classical CAD wedge front progged to push into the northeastern portion of the CWA today will serve as the main focus for convective initiation this afternoon with a more stable atmosphere north and east of this boundary. Latest HRRR represents this environment well with the classic "ring of fire" convective triggering. Development could be aided by small perturbations in the relatively weak upper flow to the north and isentropic upglide from overrunning moisture transport from the SW. Similar mid/upper thermal profile today compared to yesterday with relatively low freezing level so could again be the case for a handful of strong storms with small hail or strong gusty winds...though not anticipating anything severe. Continued likely pops near the wedge front positioning in north GA for afternoon (including line from Rome to Atlanta to Athens) then shift NEWD with mean storm motion into more stable/elevated regime. Parent sfc ridge weakens/slides off the New England coast for Wednesday so any semblance of a lingering wedge would be more hybrid in nature and possibly having some in-situ reinforcement if it can hold in the far NE CWA. Thinking should become more diffuse by midday. Possible influence from weak impulse or two aloft again warrants higher chance pops farther north for shower/general thunderstorm mention. Temps slightly cooler today given aforementioned wedge north, though still overall above climo norms. Highs mostly reaching upper 70s to mid 80s south and west. Slightly warmer for Wednesday. Baker LONG TERM /Wednesday Night through Monday/... Precip chances Wednesday night and Thursday will be mainly confined to n GA as a CAD airmass erodes with a weak nose of the upper ridge over the area but still potential for a weak short wave to aid precip chances. The European is drier than the GFS and NAM. Forecast temperatures are still running about 7-10 degrees above normal Wednesday night and Thursday. A weak cold front moves into n GA on Friday and becomes stationary. This will lead to the best precip chances over n GA and only small chances for portions of central GA. GFS and European differ rather greatly with the next system Saturday into Sunday with the European much faster bringing a strong cold front across the area Saturday night and early Sunday and the GFS bringing the front across Sunday and Sunday evening. Either way Precip chances increase Saturday night and Sunday with shower and thunderstorm potential across the area into Sunday night. This front is associated with an upper Jet and Deep 500mb trough/low pressure system. The potential for severe weather will be monitored into the weekend and timing of the front will play a significant role. Storm chances will end early Sunday night or sooner if the front is faster with just shower chances lingering into Monday associated with the upper trough/low. Above normal Temperatures will continue until Sunday then cooling to within a few degrees of normal through Monday. BDL && .AVIATION... 18Z UPDATE... SHRA beginning to develop across the ATL terminals along frontal boundary. No TS just yet but likely to develop within the hour and current 18Z to 22Z TEMPO looks good. May be able to trim off an hour or 2 here soon but need to wait to see how activity develops. Although precip should be ending this evening....MVFR and IFR deck will be moving in for the overnight period. Models not quite as aggressive with IFR potential for ATL and have removed for now but kept the MVFR cigs. //ATL CONFIDENCE...18Z UPDATE... Medium on TSRA duration. High on remaining elements. Deese && .PRELIMINARY POINT TEMPS/POPS... Athens 76 59 80 60 / 60 50 30 20 Atlanta 80 61 80 63 / 50 30 30 20 Blairsville 71 55 74 54 / 60 60 30 40 Cartersville 78 60 80 59 / 60 40 30 20 Columbus 85 62 85 63 / 10 10 20 5 Gainesville 75 58 76 61 / 60 50 30 40 Macon 85 60 83 58 / 20 20 20 10 Rome 78 60 81 59 / 60 40 30 20 Peachtree City 82 59 81 59 / 40 20 30 10 Vidalia 86 61 83 61 / 20 20 20 5 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && SHORT TERM...Deese LONG TERM....01 AVIATION...Deese
Hazardous Weather Outlook National Weather Service Peachtree City GA 303 PM EDT Tue Apr 18 2017 GAZ001>009-011>016-019>025-027-030>039-041>062-066>076-078>086- 089>098-102>113-191915- Baldwin-Banks-Barrow-Bartow-Bibb-Bleckley-Butts-Carroll-Catoosa- Chattahoochee-Chattooga-Cherokee-Clarke-Clayton-Cobb-Coweta- Crawford-Crisp-Dade-Dawson-DeKalb-Dodge-Dooly-Douglas-Emanuel- Fannin-Fayette-Floyd-Forsyth-Gilmer-Glascock-Gordon-Greene- Gwinnett-Hall-Hancock-Haralson-Harris-Heard-Henry-Houston-Jackson- Jasper-Jefferson-Johnson-Jones-Lamar-Laurens-Lumpkin-Macon- Madison-Marion-Meriwether-Monroe-Montgomery-Morgan-Murray- Muscogee-Newton-North Fulton-Oconee-Oglethorpe-Paulding-Peach- Pickens-Pike-Polk-Pulaski-Putnam-Rockdale-Schley-South Fulton- Spalding-Stewart-Sumter-Talbot-Taliaferro-Taylor-Telfair-Toombs- Towns-Treutlen-Troup-Twiggs-Union-Upson-Walker-Walton-Warren- Washington-Webster-Wheeler-White-Whitfield-Wilcox-Wilkes- Wilkinson- 303 PM EDT Tue Apr 18 2017 This Hazardous Weather Outlook is for portions of North and Central Georgia. .DAY ONE...This Afternoon and Tonight... Scattered to numerous thunderstorms are possible over north and portions of central Georgia...most so this afternoon into the evening. Storms may be strong to isolated severe with the primary hazards being Gusty Winds...Large Hail...Frequent Lightning and Locally Heavy Rain. .DAYS TWO THROUGH SEVEN...Wednesday through Monday... There will be a chance of thunderstorms over portions of north and central Georgia Wednesday through Sunday. There is some potential for severe storms later Saturday and Sunday. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed through tonight.
Special Weather Statement
National Weather Service Peachtree City GA
245 PM EDT TUE APR 18 2017
GAZ033-034-045-181930-
North Fulton GA-DeKalb GA-Gwinnett GA-
245 PM EDT TUE APR 18 2017
...SIGNIFICANT WEATHER ADVISORY FOR NORTH FULTON...NORTHWESTERN
DEKALB AND SOUTHWESTERN GWINNETT COUNTIES UNTIL 330 PM EDT...
At 244 PM EDT...a strong thunderstorm was over Doraville, moving
northeast at 10 mph.
HAZARD...Up to 40 mph wind, pea sized hail and frequent cloud-to-
ground lightning.
IMPACT...Expect minor damage to tree limbs and the blowing around
of light, unsecured objects.
Some locations in the path of this storm include
Sandy Springs, Roswell, Johns Creek, Dunwoody, Duluth, Lilburn,
Chamblee, Norcross, Doraville, Clarkston, Stone Mountain, Berkeley
Lake, Tucker, North Decatur, North Atlanta, Mountain Park,
Mechanicsville and Scottdale.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
People outdoors should seek shelter immediately. If you can hear
thunder...you are close enough to be struck by lightning.
LAT...LON 3380 8428 3396 8436 3406 8417 3397 8409
3382 8407
TIME...MOT...LOC 1844Z 235DEG 9KT 3391 8427
HAIL...0.25IN
WIND...40MPHThe Atlanta radar (KFFC), 65 km away, was scanning. The volume nearest the first event began at 19:06 UTC.
1 hail. Local standard time, as filed.
The attendant at a gas station at the corner of Stonecrest Court and Chamblee Tucker Road reported quarter size hail.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Georgia in 2017Every state in 2017This day in weather historyWarnings in Georgia, April 2017
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 695891.