Alert archive / Tennessee / Mesoscale Discussions in 2017

Mesoscale Discussion 161

February 8, 20174 states

The Storm Prediction Center issued this mesoscale discussion at Feb 8, 2017, 7:04 PM CST for 4 states. It was in force for 86 min.

The area

The outline as issued.

The facts

Issued
Feb 8, 2017, 7:04 PM CST (01:04 UTC)
Expired
Feb 8, 2017, 8:30 PM CST
In force
86 min
Issued by
the Storm Prediction Center
All 80 counties

Blount County, AL, Cherokee County, AL, Colbert County, AL, Cullman County, AL, DeKalb County, AL, Etowah County, AL, Franklin County, AL, Jackson County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Madison County, AL, Marion County, AL, Marshall County, AL, Morgan County, AL, Winston County, AL, Bartow County, GA, Catoosa County, GA, Chattooga County, GA, Cherokee County, GA, Dade County, GA, Fannin County, GA, Floyd County, GA, Gilmer County, GA, Gordon County, GA, Murray County, GA, Pickens County, GA, Polk County, GA, Walker County, GA, Whitfield County, GA, Cherokee County, NC, Graham County, NC, Anderson County, TN, Bedford County, TN, Bledsoe County, TN, Blount County, TN, Bradley County, TN, Cannon County, TN, Cheatham County, TN, Coffee County, TN, Cumberland County, TN, Davidson County, TN, DeKalb County, TN, Fentress County, TN, Franklin County, TN, Giles County, TN, Grainger County, TN, Grundy County, TN, Hamblen County, TN, Hamilton County, TN, Jackson County, TN, Jefferson County, TN, Knox County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Loudon County, TN, Marion County, TN, Marshall County, TN, Maury County, TN, McMinn County, TN, Meigs County, TN, Monroe County, TN, Moore County, TN, Morgan County, TN, Overton County, TN, Polk County, TN, Putnam County, TN, Rhea County, TN, Roane County, TN, Rutherford County, TN, Sequatchie County, TN, Sevier County, TN, Smith County, TN, Union County, TN, Van Buren County, TN, Warren County, TN, White County, TN, Williamson County, TN, Wilson County, TN

The radar

The Northeast Alabama radar (KHTX), 17 km from the middle of the area, began a volume at 01:03 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 nearest sounding before it

Nashville Metro, TN (KBNA), launched 00:00Z, 1.1 hours before the alert went out and 137 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-pSkew-T log-p diagram, Nashville Metro, TN at 00:00Z on 2017-02-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Nashville Metro, TN at 00:00Z on 2017-02-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 131 square meters per square second.1939587897117136Sfc1 km3 km6 km9 kmRMLM
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
3 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
466 m above ground
0-6 km bulk shear
61 kt
0-1 km storm-relative helicity
131 m²/s²
0-3 km storm-relative helicity
222 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.6

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 8, 8:55 PM CSTMesoscale DiscussionSPCBlount, Cherokee, Colbert, Cullman, DeKalb, Etowah and 10 more65 min
Feb 9, 2:12 AM CSTMesoscale DiscussionSPCBryan, Bulloch, Candler, Chatham, Effingham, Evans and 4 more2 hr

Nearby

Mesoscale Discussions in Tennessee, 2017Mesoscale Discussions in Alabama, 2017Mesoscale Discussions in Georgia, 2017Every mesoscale discussion in 2017

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.