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Guest Post: Conditions Behind the 1936 Gainesville (GA) Tornado

| April 9, 2011 @ 9:45 am | 2 Replies

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Perry Williams is a weather enthusiast who lives in Newnan, Georgia. He keeps a close eye on the weather on his Facebook page. This week, he posted an excellent analysis of the weather conditions on the morning of the terrible Gainesville (GA) tornado that killed over 200 people on the morning of April 6, 1936. This same storm system produced a devastating tornado killed 216 people in Tupelo, Mississippi the evening before. He granted us permission to post it here…

I’ve wondered for many years just how warm and unstable the weather conditions were in Atlanta and north Georgia the morning the infamous Gainesville tornado occurred at 8:30 a.m. EST on Monday April 6, 1936. After finally receiving weather data from the National Climatic Data Center this evening with hourly weather obs from the Atlanta municipal airport (present day Hartsfield-Jackson International; weather station was north of runways), can categorically state it was very warm, sticky, and what old timers round these parts call “tornado weather”. The near record freeze of 32 degrees on the morning of April 4th, 1936 was quickly replaced by very warm and unstable air rushing north from the Gulf of Mexico.

The first week of April 1936 was a wild week weatherwise across the southeast U.S. A deadly tornado outbreak occurred on April 2nd, producing a killer early morning (7:30 a.m.) F4 tornado that killed 23 and injured hundreds in Cordele, Georgia….a small farming community between Macon and Tifton. During the day, several strong to intense tornadic storms occurred across Georgia and the Carolinas, with a particularly vicious tornado roaring across Greensboro, North Carolina during the evening. Fourteen died there as the cold front raced through the area. Rainfall totalled more than two inches at Atlanta, and some areas of north and central Georgia experienced flooding.

The strong cold frontal passage brought much colder, drier air into the southeast, with Atlanta, Georgia reaching 32 degrees on both April 3 and 4th. With such frosty, unseasonably temperatures, I imagine the thought of more killer tornadoes before the end of the weekend would have shocked many residents of Mississippi, Alabama, Georgia, and Tennessee. Another very strong weather system began moving eastward out of the southern Rockies on April 4th, and data indicates strong southerly winds quickly brought warm moist air back to western and southern portions of the southeast states. I have seen a U.S. weather surface chart for 7 p.m. EST (00z) on April 5th, and it shows temperatures near or over 70 and dewpoints well into the 60’s across Mississippi, Alabama, and southern Georgia at that time. This was only 3-4 hours before the infamous F5 “Tupelo” tornado touched down in Mississippi, killing 219 and injuring over 800 in a horrific rampage across several counties. Other significant tornadoes occurred during Sunday night across northern Mississippi and Alabama into southern middle Tennessee.

Evidence in the 00z synoptic chart and surface data from Atlanta clearly show the slow retreat of the cold air from north and central Georgia on Saturday into Sunday afternoon, as strong east winds and “wedge front” kept it cool with rain, drizzle, and fog. Conditions slowly warmed in the Atlanta area that day. but remained cool and stable with rain falling. The 00z chart (7 p.m. EST Sunday evening) showed Atlanta with fog, rain, and a temperature and dewpoint of 55 at that time, and IS CONFIRMED by the surface date I obtained tonight. Saturday morning April 5th began with a temperature of of 43 and only reached 51 by 4 p.m. However, as I’ve observed many times during the past…..surface temperatures and dewpoints continued rising throughout the evening and overnight and reached very favorable parameters for tornadoes and severe thunderstorms by late evening (Sunday April 5th). At the time the Tupelo tornado occurred (9 p.m. CST) it had already risen to 66 degrees with 64 degree dewpoint (rising 14 degrees between 4-11 p.m.).

The temperature and other surface weather parameters in Atlanta suggest a very favorable tornadic supercell enviroment during the night (early morning April 6th), reaching 70 with dewpoint well into the 60’s and strong south winds as dawn approached. My late grandmother was 22 years old at the time, and vividly recalled it being very warm, muggy, and windy that morning……and very stormy looking overhead with dark ominous clouds passing over their family farm in southern Paulding county, Georgia (along present day Ridge Road just east of the New Georgia community). In fact, she stated her father, her younger brother, one younger sister and herself went outside around 6 a.m. to take care of their stock (horses, chickens, pigs, cows, etc) and continue spring planting. Granny said that a bad storm approached from the southwest between 6:30 and 7 a.m., and they all ran for the storm cellar; my grandmother recalled lots of lightning; the sky pitch black with a greenish tint. Shortly afterwords, hail as large as tennis balls fell at their home.

This was apparently the same supercell thunderstorm that produced a strong (F2) tornado near Acworth and Lake Allatoona (7:20 a.m.) and the Gainesville tornado at 8:27 a.m. The last hourly ob taken at Atlanta before the tornado struck Gainesville was 8 a.m. EST, when the temperature and dewpoint at Atlanta was 71/ 66 with strong SSW winds. Since warm frontal passage occurred some 12 hrs earlier, it’s reasonable to assume similar conditions existed at Gainesville, only 45 miles to the northeast; temperature at least in the upper 60’s with dewpoint above 64.

Here are a few select surface obs for Atlanta Municipal airport from April 4th, 5th, and 6th, 1936

Saturday April 4th
7 p.m. EST…….cloudy………47/ 31…..SSE @ 10 mph……30.21″ (1023.0 mb)’….after low of 32 degrees

Sunday April 5th
12 a.m. EST……cloudy……..46/ 32……ENE @ 6 mph……..30.21″ (1023.0 mb)
5 a.m. EST…….lt rain………44/ 43…….E @ 10 mph……….30.12″ (1020.0 mb)
10 a.m. EST…..rain/ fog…..48/ 47…….NE @ 14 mph……..30.05″ (1017.9 mb)
2 p.m. EST……rain/ fog…..51/ 50…….E @ 12 mph………..29.96″ (1014.6 mb)
7 p.m. EST……fog………….55/ 55…….E @ 6 mph…………29.85″ (1011.2 mb)…./ rainfall past 24 hr 1.19″
8 p.m. EST…..thick fog……58/ 58……SE @ 12 mph………29.82″ (1010.2 mb)
9 p.m. EST……fog………….60/ 58……S @ 14 mph………..29.79″ (1009.1 mb)
10 p.m. EST….cloudy……..66/ 64…….S @ 21 mph……….29.76″ (1007.8 mb)…**Tupelo MS F5 was on ground
11 p.m. EST…..cloudy…….67/ 65…….S @ 23 mph……….29.76″ (1007.8 mb)

Monday April 6th
12 a.m. EST….p cloudy…..67/ 65…….SSW @ 21 mph……29.75″ (1007.5 mb)
1 a.m. EST…..p cloudy…..68/ 65……..S @ 23 mph……….29.76″ (1007.8 mb)
2 a.m. EST…..cloudy……..68/ 65…….SW @ 20 mph…….29.76″ (1007.8 mb)
3 a.m. EST…..p cloudy…..69/ 64…….SSE @ 20 mph…….29.77″ (1008.1 mb)
4 a.m. EST…..p cloudy…..69/ 64……..SW @ 20 mph…….29.77″ (1008.1 mb)
5 a.m. EST…..p cloudy…..69/ 64…….SW @ 20 mph…….29.77″ (1008.1 mb)
6 a.m. EST…..cloudy…….67/ 64…..SSW @ 18 mph….29.77″ (1008.1 mb)
7 a.m. EST…..overcast…..70/ 64…..SSW @ 18 mph….29.82″ (1009.5 mb)…./ rainfall since 7 p.m. trace
8 a.m. EST…..overcast…..71/ 66…..SSW @ 13 mph….29.79″ (1008.8 mb) **25-30 min before Gainesville F4 struck**
9 a.m. EST….t-storm…….70/ 66…..SSW @ 22 mph….29.73″ (1006.8 mb) **20 min after Gainesville F4 lifted**
10 a.m. EST…rain………..58/ 57….,..N @ 6 mph………..29.88″ (1011.9 mb)
12 p.m. EST….tstorm……59/ 59…..S @ 2 mph………..29.88″ (1011.9 mb)
2 p.m. EST…..hvy rain….60/ 59…..S @ 4 mph………..29.88″ (1011.9 mb)
4 p.m. EST….rain………..60/ 58…..N @ 4 mph……….29.87″ (1011.5 mb)
7 p.m. EST….rain………..57/ 57…..S @ 3 mph……….29.89″ (1012.5 mb)…./ rainfall since 7 a.m. 2.06″
11 p.m. EST….hvy rain….56/ 56…..E @ 3 mph………29.90″ (1012.9 mb)

Tuesday April 7th
7 a.m. EST…..cloudy……..49/ 48…..NW @ 9 mph……30.02″ (1016.6 mb)…./ rainfall since 7 p.m. 2.20″

This data proves beyond shadow of a doubt that the atmosphere over north Georgia was destabilizing rapidly during the night and pre-dawn hours of Monday April 6th, 1936, and met all parameters for a violent tornado to occur in the Gainesville area at the time it happened (8:25 to 9:00 a.m.).

Even after the front passed Atlanta, very heavy rain continued in the cooler air……a total of 1.19″ fell on April 5th and 4.26″ on April 6th (a storm total of 5.45″, only a few days after very heavy rain fell during the Cordele-Greenesboro tornado outbreak).

Perry

Category: Met 101/Weather History

About the Author ()

Bill Murray is the President of The Weather Factory. He is the site's official weather historian and a weekend forecaster. He also anchors the site's severe weather coverage. Bill Murray is the proud holder of National Weather Association Digital Seal #0001 @wxhistorian

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