This afternoon’s thunderstorms were responsible for hail, damaging winds and even a few tornadoes to Georgia, but on the upside, they brought needed rain as well.  In advance of an approaching cold front, the storms fired up from west to east, with the worst of the storms affecting the Atlanta area between 5 and 6 PM.

Looking at the Georgia storm reports,  there were reports of damaging winds bringing down power lines and trees in west Georgia, tornado spottings in southwest Georgia and quarter inch hail.  In metro Atlanta, some minor flooding was reported in Tucker, and there were tornado warnings issued for Fulton and Gwinnett counties based on radar soundings, however no tornadoes were reported in the metro area.

The storm did bring some needed rain to the area.  As of 7:30 PM, here are some reported rain amounts:

Alpharetta: 1.18 inches
Johns Creek: 1.18 inches
Dunwoody: 1.21 inches
Gainesville: 1.17 inches
Lawrenceville:  0.77 inches
Dahlonega: 0.98 inches
Jonesboro: 0.36 inches
Dallas: 1.01 inches

The good news is that the heaviest rains occurred on the north side of the metro area, and should add to the runoff into lakes Lanier and Allatoona. With the cold front pushing in, any additional rainfall tonight will be light.  And, with more rain predicted for the end of the week, we might be able to make a dent in the slow refilling of the lakes.

It looks like much of Gwinnett and Atlanta is getting needed rainfall this evening, as a relatively unexpected storm system moved in. Here in South Gwinnett, I’ve recorded .91 inches of rain. During the most intense parts of the storm, I saw quarter-sized hail, and for a period of about 20 minutes, hail ranging from the size of Kix cereal to the size of a jellybean fell.

This system is a bit unusual, in that it moved from northeast to southwest, the opposite of most systems. In a bit of a reverse of the fairly common cold air damming, a cold pool of air in the upper atmosphere came south, and ran into the warmer, moist air from the southwest that was already in place, causing the storms and hail. Typically, storms move from west to east, following the prevailing wind patterns.

The cold pool will be south of us tomorrow, reducing the chance of rain. However, it looks like we are in a fairly normal summer pattern, which is good news for the drought. If we get an inch or rain like this every week, even though there will be a deficit, the excessively dry conditions will be a thing of the past.

The massive cool down predicted for the weekend, with temperatures anywhere between 20 and 30 degrees cooler than they have been, has set up a high possibility of thunderstorms, hail, and possible tornadoes for Friday afternoon, and into early Saturday morning.

In an early morning severe weather outlook, the Storm Prediction Center predicted the greatest likelihood of severe storms in most of Alabama and western Georgia, stretching north through Tennessee and Kentucky.

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Shortly after I got to Sugarloaf Country Club and the BellSouth Classic at 10:00 this morning, an unexpected round of sleet and snow passed over the course. Walking along the 12th fairway, conditions deteriorated rapidly, as rain and sleet began to fall.

Fortunately, a corporate hospitality “Sky Box” was at the 10th green, and its owners were kind enough to let the few spectators in the area in for the duration of the storm, which was about 20 minutes. The whole thing caused about an hour and a half delay of the tournament, although conditions improved (if 55 degrees and 30 MPH winds can be called an improvement).

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Just in time for severe weather awareness week, North Georgia received its first major round of thunderstorms for the season on Monday, February 21st.

About noon, a severe thunderstorm warning was sounded for counties in northwest Georgia. By shortly after 1 PM, a severe thunderstorm was spotted in the Lilburn area, and an additional warning was issued shortly after 1:35 for Gwinnett, Walton, and Barrow counties, with storms located in Tucker and Loganville. A large area from Alabama, through 58 counties in north Georgia, and into South Carolina was put under a severe thunderstorm watch until 7PM.

A second wave of thunderstorms crossed North Gwinnett around 6:30, with hail the size of golf balls predicted from north of Duluth east to Buford and Sugar Hill. Shortly before 7PM an additional warning was issued for DeKalb and Gwinnett Counties until 7:45, again with predictions of golf ball size hail through Lilburn and Lawrenceville. As of 7:15, I was observing hail the size of peas outside my house (and hoping the hood of the truck wasn’t going to become damaged). By about 7:30 that phase of the storm had passed through the area. At 7:50, an additional warning was issued for Gwinnett until 8:15.

Due to the continuing presence of the storm, a second watch that included 67 Georgia counties, many further south than the first watch, was put into effect until 2 AM Tuesday. This map shows the size of the second watch, and radar in the area as of about 7:00 PM:

(Courtesy of the National Weather Service.)

Damage reports from the storm include 1 inch hail reported in Snellville and Grayson around 1:30 PM, 2 inch hail in Rome and Canton around 5:30 PM, and 1.75 inch hail around 7:30 PM in Winder. Although some of these reports were from the public, trained spotters reported 1.75 inch hail in Lilburn and Snellville between 7:20 and 7:50 PM.

Rain caused by the storms prompted flood warnings in northwest Georgia, and along the Etowah river near Dawsonville. By 8:45, enough rain had fallen in Gwinnett to issue a generalized flood warning for the county. Both the Big Creek in Alpharetta and the Chattahoochee near Vinings were close to flood stage on Tuesday morning.

Here we measured 1.96 inches of rain on Monday, and a total of 2.41 inches of rain for the storm which began on Sunday. The rain in the last 24 hours measures more than a third of the 6.16 inches so far this year.

This post was originally published at 1:30PM on 2/21/05, and has been updated several times to reflect current conditions.