Alert archive / Georgia / Mesoscale Discussions in 2009

Mesoscale Discussion 375

April 2, 20094 states

The Storm Prediction Center issued this mesoscale discussion at Apr 2, 2009, 5:25 PM CDT for 4 states. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued: Apr 2, 2009, 5:25 PM CDT (22:25 UTC)
Expired: Apr 2, 2009, 7:00 PM CDT
In force: 95 min
Issued by: the Storm Prediction Center

All 59 counties

Calhoun County, AL, Cherokee County, AL, Cleburne County, AL, DeKalb County, AL, Bartow County, GA, Carroll County, GA, Catoosa County, GA, Chattooga County, GA, Cherokee County, GA, Cobb County, GA, Dade County, GA, Dawson County, GA, Douglas County, GA, Fannin County, GA, Floyd County, GA, Forsyth County, GA, Gilmer County, GA, Gordon County, GA, Hall County, GA, Haralson County, GA, Lumpkin County, GA, Murray County, GA, Paulding County, GA, Pickens County, GA, Polk County, GA, Towns County, GA, Union County, GA, Walker County, GA, White County, GA, Whitfield County, GA, Cherokee County, NC, Clay County, NC, Graham County, NC, Anderson County, TN, Bledsoe County, TN, Blount County, TN, Bradley County, TN, Cumberland County, TN, Fentress County, TN, Grundy County, TN, Hamilton County, TN, Knox County, TN, Loudon County, TN, Marion County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Morgan County, TN, Overton County, TN, Polk County, TN, Putnam County, TN, Rhea County, TN, Roane County, TN, Scott County, TN, Sequatchie County, TN, Sevier County, TN, Union County, TN, Van Buren County, TN, White County, TN

The radar

The Northeast Alabama radar (KHTX), 115 km from the middle of the area, began a volume at 22:26 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Tornado Watch 112Apr 2, 6:00 PM CDT

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 10.4 hours before the alert went out and 185 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 36 J/kg
Mixed-layer CIN: -191 J/kg
Mixed-layer LCL: 667 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 148 m²/s²
0-3 km storm-relative helicity: 152 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 2, 3:12 AM CDT	Mesoscale Discussion	SPC	Chambers, Clay, Cleburne, Lee, Randolph, Tallapoosa	63 min
Apr 2, 5:57 AM CDT	Mesoscale Discussion	SPC	Baldwin, Barbour, Bullock, Butler, Coffee, Conecuh and 9 more	63 min
Apr 2, 6:29 AM CDT	Tornado Watch	SPC	Baldwin, Barbour, Bullock, Butler, Choctaw, Clarke and 19 more	8 hr
Apr 2, 10:06 AM CDT	Mesoscale Discussion	SPC	Dale, Geneva, Henry, Houston	54 min
Apr 2, 1:09 PM CDT	Mesoscale Discussion	SPC	Autauga, Baldwin, Bibb, Blount, Butler, Calhoun and 45 more	66 min
Apr 2, 1:33 PM CDT	Tornado Watch	SPC	Autauga, Baldwin, Bibb, Blount, Butler, Chilton and 36 more	5 hr
Apr 2, 2:00 PM CDT	Tornado Watch	SPC	Coffee, Dale, Geneva, Henry, Houston	7 hr
Apr 2, 3:42 PM CDT	Mesoscale Discussion	SPC	Autauga, Bibb, Blount, Butler, Chilton, Coffee and 29 more	63 min
Apr 2, 6:02 PM CDT	Tornado Watch	SPC	Autauga, Bibb, Blount, Calhoun, Chambers, Cherokee and 38 more	7 hr
Apr 2, 7:31 AM CDT	Tornado Watch	SPC	Appling, Atkinson, Bacon, Brantley, Camden, Charlton and 16 more	6 hr
Apr 2, 12:17 PM CDT	Mesoscale Discussion	SPC	Brantley, Camden, Charlton, Clinch, Echols, Pierce and 1 more	58 min
Apr 2, 6:28 PM CDT	Mesoscale Discussion	SPC	Brantley, Camden, Charlton, Clinch, Echols, Lanier and 2 more	92 min
Apr 2, 10:53 AM CDT	Tornado Watch	SPC	Chester, Fayette, Hardeman, Hardin, McNairy, Shelby	4 hr
Apr 2, 2:04 PM CDT	Mesoscale Discussion	SPC	Cheatham, Davidson, Houston, Macon, Montgomery, Robertson and 4 more	116 min
Apr 2, 2:40 PM CDT	Tornado Watch	SPC	Benton, Cheatham, Davidson, DeKalb, Dickson, Houston and 9 more	4 hr
Apr 2, 4:35 PM CDT	Mesoscale Discussion	SPC	Clay, Jackson, Pickett	85 min
Apr 2, 5:36 PM CDT	Mesoscale Discussion	SPC	Carroll, Chester, Crockett, Dyer, Fayette, Gibson and 11 more	84 min
Apr 2, 6:21 PM CDT	Tornado Watch	SPC	Carroll, Chester, Crockett, Decatur, Dyer, Fayette and 14 more	3 hr

Nearby

Mesoscale Discussions in Georgia, 2009 Mesoscale Discussions in Tennessee, 2009 Mesoscale Discussions in Alabama, 2009 Every mesoscale discussion in 2009

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.