2/18/09 DISC: MS/AL/GA

[John Farley]

Confirmed tornadoes thus far:

Atlanta/Peachtree City, GA CWA:

5 tornadoes, including a 1/2-mile wide EF4 in Wilkes County, a mile-wide EF2 in Coweta County, and a 1/4-mile wide EF2 in Putnam County.


Birmingham, AL CWA:

1 tornado, a 500-yard wide (but just 1 mile long) EF1 in Randolph County. Much of the other damage in this CWA was determined to have resulted from straight-line winds; just this one tornado confirmed.


Tallahassee, FL CWA:

Confirmed tornado path or paths in Grady, Thomas, and Lowndes Counties, GA but surveys still under way to determine path length and number of tornadoes.

 

[Danny Neal]

Wow, thanks for posting this John. I looked earlier this morning, I don't know if I missed it or was looking in the wrong place (lol) I guess the NWS was playing the safe card with the LSR's...... Perhaps there were no spotters? Which is pretty hard to believe.

 

[mikegeukes]

[FONT=lucida sans typewriter, lucida console, courier]PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
418 PM EST THU FEB 19 2009
..PRELIMINARY TORNADO REPORTS FOR NORTH AND CENTRAL GEORGIA
[/FONT]
WILKES COUNTY...THE STORM REACHED THE WESTERN PART OF THE COMMUNITY OF TYRONE...
NEAR HIGHWAY 44 AT 710 PM AND EXTENDED FOR 16 MILES IN LENGTH AND ONE HALF MILE WIDE.

THE STORM WAS RATED AN EF4 WITH DEBRIS FROM THE DEMOLISHED HOME
BEING CARRIED AT LEAST ONE HALF MILE.
-
Read more about the tornadoes:
http://kamala.cod.edu/offs/KFFC/0902192118.nous42.html

[FONT=lucida sans typewriter, lucida console, courier]
PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE BIRMINGHAM AL
300 PM CST THU FEB 19 2009
..SEVERE WEATHER EVENT ACROSS CENTRAL ALABAMA
[/FONT]http://kamala.cod.edu/offs/KBMX/0902192058.nous44.html

 

[J Kinkaid]

Confirmed tornadoes thus far:

Atlanta/Peachtree City, GA CWA:

5 tornadoes, including a 1/2-mile wide EF4 in Wilkes County, a mile-wide EF2 in Coweta County, and a 1/4-mile wide EF2 in Putnam County.


Birmingham, AL CWA:

1 tornado, a 500-yard wide (but just 1 mile long) EF1 in Randolph County. Much of the other damage in this CWA was determined to have resulted from straight-line winds; just this one tornado confirmed.


Tallahassee, FL CWA:

Confirmed tornado path or paths in Grady, Thomas, and Lowndes Counties, GA but surveys still under way to determine path length and number of tornadoes.

Mobile,AL had one also EF1 in Mcintosh, AL back on Jan 10
http://www.srh.noaa.gov/mob/McIntoshTornado.htm

 

[Dave Gallaher]

Regarding the apparent lack of actual touchdowns in Alabama, my friend at NWS HSV says he thinks two main reasons were that the temp/dewpoint spreads were too large for low LCL's to develop, and because of uni-directional low level shear.

 

[Howard Robinson]

NWS FFC has a preliminary tornado report out now, looks like EF0's EF2's
http://www.srh.noaa.gov/productview.php?pil=PNSFFC&version=0&max=61

 

[mikegeukes]

[FONT=lucida sans typewriter, lucida console, courier]PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TALLAHASSEE FL
732 PM EST THU FEB 19 2009

...STORM SURVEY CONDUCTED IN THOMAS COUNTY GEORGIA TODAY FINDS
STRONG EF-2 TORNADO...
[/FONT]http://kamala.cod.edu/offs/KTAE/0902200032.nous42.html

 

[mikegeukes]

More information from Georgia.
[FONT=lucida sans typewriter, lucida console, courier]PUBLIC INFORMATION STATEMENT...CORRECTED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
815 PM EST THU FEB 19 2009

...PRELIMINARY TORNADO REPORTS FOR NORTH AND CENTRAL GEORGIA FOR THE
EVENING OF FEB 18 2008...
[/FONT]http://kamala.cod.edu/offs/KFFC/0902200117.nous42.html

 

[Bill Hark]

Regarding the apparent lack of actual touchdowns in Alabama, my friend at NWS HSV says he thinks two main reasons were that the temp/dewpoint spreads were too large for low LCL's to develop, and because of uni-directional low level shear.

I agree, especially with the lower level winds. The early morning models (RUC, WRF) showed SW winds at the surface and 850mb levels for the entire day. The actual obs confirmed this except for a small area in NW GA of backed surface winds. I think nice photogenic tornadoes are rare with SW surface and SW 850 mb winds.


Bill Hark

 

[mikegeukes]

[FONT=lucida sans typewriter, lucida console, courier]PUBLIC INFORMATION STATEMENT...CORRECTED
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1230 PM EST FRI FEB 20 2009
...PRELIMINARY TORNADO REPORTS FOR NORTH AND CENTRAL GEORGIA FOR THE
EVENING OF FEB 18 2008...
[/FONT][FONT=lucida sans typewriter, lucida console, courier].CHANGED EF RATING FOR WILKES COUNTY TO EF3
[/FONT]Click here for more information on the 10 tornadoes.
http://kamala.cod.edu/offs/KFFC/0902201719.nous42.html

 

[Bob Hartig]

In the light of these last two posts, does anyone know what happened that sparked the limited but intense tornadic activity in Georgia? I'm guessing that surface and low-level winds backed enough to cause a spike in helicity that integrated with a narrower dewpoint depression after dark.

 

[John Farley]

The Tallahassee NWS is now reporting that its surveys indicate two tornadoes along the nighttime supercell's path across south Georgia, a 16.5-mile EF2 in Grady and Thomas Counties, and a short-track (1.5 miles) EF3 in eastern Thomas County:

More info at:

http://www.srh.noaa.gov/tlh/events/2009/svrwx021909/

 

[mikegeukes]

Bob Hartig ,

This may help you out or not, remember time is in UTC,
So look at February 18 and 19 for the data.

Archived National SPC Sector: SPC Hourly Mesoscale Analysis
http://w1.spc.woc.noaa.gov/exper/ma_archive/

Daily Archived Directory:
http://w1.spc.woc.noaa.gov/exper/ma_archive/images_s4/

SPC Severe Thunderstorm Events
http://www.spc.noaa.gov/exper/archive/events/090218/index.html

Mike
Lansing, MI

 

[Jason Harris]

Why was the EF-3 tornado track so brief compared to the EF-2 track? Wouldn't one expect the more intense tornado to last longer with more favorable conditions in general for the storm? What happened?

 

[Bob Hartig]

Bob Hartig ,

This may help you out or not, remember time is in UTC,
So look at February 18 and 19 for the data.

Archived National SPC Sector: SPC Hourly Mesoscale Analysis
http://w1.spc.woc.noaa.gov/exper/ma_archive/

Daily Archived Directory:
http://w1.spc.woc.noaa.gov/exper/ma_archive/images_s4/

SPC Severe Thunderstorm Events
http://www.spc.noaa.gov/exper/archive/events/090218/index.html

Mike
Lansing, MI

Mike, thanks for the links. I found my answer at the SPC site in the 00Z skew-T/hods at Atlanta, Tallahassee, and Jacksonville. There was some serious turning from the surface to mid levels, particularly in the lower 1-2 km. While all the surface obs and models I've seen have shown majorly veered winds, the soundings indicate surface winds blowing from the south and even slightly southeast. I'm no expert at hodographs, but the one for Atlanta looks pretty impressive to me.

On a side note, it seems to me that Dixie Alley's location to the north and northeast of the Gulf of Mexico makes southwesterly 850s much less of a concern for moisture transport in most of that region than in the Plains states.