Alert archive / Tennessee / Mesoscale Discussions in 2017

Mesoscale Discussion 281

March 9, 201713 counties in Kentucky; 29 counties in Tennessee

The Storm Prediction Center issued this mesoscale discussion at Mar 9, 2017, 7:58 PM CST for 13 counties in Kentucky; 29 counties in Tennessee. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued
Mar 9, 2017, 7:58 PM CST (01:58 UTC)
Expired
Mar 9, 2017, 9:30 PM CST
In force
92 min
Issued by
the Storm Prediction Center
Chance of a watch
80%
All 42 counties

Caldwell County, KY, Calloway County, KY, Christian County, KY, Crittenden County, KY, Graves County, KY, Livingston County, KY, Logan County, KY, Lyon County, KY, Marshall County, KY, McCracken County, KY, Simpson County, KY, Todd County, KY, Trigg County, KY, Bedford County, TN, Cannon County, TN, Cheatham County, TN, Coffee County, TN, Davidson County, TN, Dickson County, TN, Franklin County, TN, Giles County, TN, Hickman County, TN, Houston County, TN, Humphreys County, TN, Lawrence County, TN, Lewis County, TN, Lincoln County, TN, Macon County, TN, Marshall County, TN, Maury County, TN, Montgomery County, TN, Moore County, TN, Perry County, TN, Robertson County, TN, Rutherford County, TN, Smith County, TN, Stewart County, TN, Sumner County, TN, Trousdale County, TN, Wayne County, TN, Williamson County, TN, Wilson County, TN

The radar

The Ft Campbell radar (KHPX), 47 km from the middle of the area, began a volume at 01:57 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.

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 00:00Z, 2.0 hours before the alert went out and 95 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 2017-03-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2017-03-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 111 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2824 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
111 m²/s²
0-3 km storm-relative helicity
169 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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
Mar 9, 6:42 PM CSTSevere Thunderstorm WatchSPCBenton, Carroll, Chester, Crockett, Decatur, Dyer and 15 more5 hr
Mar 9, 8:38 PM CSTSevere Thunderstorm WatchSPCBedford, Cannon, Cheatham, Coffee, Davidson, DeKalb and 24 more4 hr
Mar 9, 9:30 PM CSTMesoscale DiscussionSPCBenton, Carroll, Chester, Crockett, Dyer, Gibson and 10 more90 min
Mar 9, 10:42 PM CSTMesoscale DiscussionSPCBedford, Cannon, Cheatham, Chester, Coffee, Davidson and 32 more63 min
Mar 9, 11:18 PM CSTSevere Thunderstorm WatchSPCFranklin, Lincoln, Marion, Moore4 hr
Mar 10, 12:50 AM CSTMesoscale DiscussionSPCBledsoe, Bradley, Hamilton, McMinn, Marion, Meigs and 4 more85 min

Nearby

Mesoscale Discussions in Tennessee, 2017Mesoscale Discussions in Kentucky, 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.