Alert archive / Tennessee / Severe Thunderstorm Watches in 2018

Severe Thunderstorm Watch 238

June 28, 201827 counties in Tennessee

The Storm Prediction Center issued this severe thunderstorm watch at Jun 28, 2018, 8:55 PM CDT for 27 counties in Tennessee. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Jun 28, 2018, 8:55 PM CDT (01:55 UTC)
Expired
Jun 29, 2018, 12:56 AM CDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
60 kt
All 27 counties

Benton County, TN, Carroll County, TN, Cheatham County, TN, Chester County, TN, Crockett County, TN, Decatur County, TN, Dickson County, TN, Fayette County, TN, Giles County, TN, Hardeman County, TN, Hardin County, TN, Haywood County, TN, Henderson County, TN, Hickman County, TN, Houston County, TN, Humphreys County, TN, Lawrence County, TN, Lewis County, TN, Madison County, TN, Maury County, TN, McNairy County, TN, Montgomery County, TN, Perry County, TN, Stewart County, TN, Tipton County, TN, Wayne County, TN, Williamson County, TN

The radar

The Memphis radar (KNQA), 123 km from the middle of the area, began a volume at 01:56 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
5%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
5%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
40%

Warnings issued inside it

8 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jun 28, 9:11 PM CDTSevere Thunderstorm WarningMEGBenton, Carroll, Gibson, Henry, Weakley49 min
Jun 28, 9:15 PM CDTSevere Thunderstorm WarningOHXDickson, Houston, Humphreys, Montgomery, Stewart45 min
Jun 28, 9:22 PM CDTSevere Thunderstorm WarningMEGCrockett, Dyer, Lake, Obion68 min
Jun 28, 9:27 PM CDTSevere Thunderstorm WarningMEGBenton, Henry, Obion, Weakley33 min
Jun 28, 9:55 PM CDTSevere Thunderstorm WarningMEGBenton, Carroll, Crockett, Decatur, Gibson, Henderson and 4 more65 min
Jun 28, 10:01 PM CDTSevere Thunderstorm WarningMEGCrockett, Dyer, Gibson, Lake, Lauderdale, Obion59 min
Jun 28, 10:13 PM CDTSevere Thunderstorm WarningMEGCrockett, Dyer, Hardeman, Haywood, Lauderdale, Tipton62 min
Jun 28, 10:27 PM CDTSevere Thunderstorm WarningMEGCarroll, Chester, Crockett, Decatur, Gibson, Hardeman and 4 more48 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Little Rock, AR (KBYH), launched 00:00Z, 1.9 hours before the alert went out and 155 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, Little Rock, AR at 00:00Z on 2018-06-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2733 joules per kilogram.LCLLFCEL10008507005003002001001 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, Little Rock, AR at 00:00Z on 2018-06-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -21 square meters per square second.1939Sfc1 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
2733 J/kg
Mixed-layer CIN
-27 J/kg
Mixed-layer LCL
1855 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
-21 m²/s²
0-3 km storm-relative helicity
-8 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 28, 7:01 PM CDTMesoscale DiscussionSPCClarke, George, Greene, Jackson, Jasper, Jones and 4 more89 min
Jun 28, 8:39 PM CDTMesoscale DiscussionSPCAlcorn, Benton, DeSoto, Marshall, Prentiss, Tippah and 1 more96 min
Jun 28, 11:00 PM CDTMesoscale DiscussionSPCAlcorn, Benton, DeSoto, Marshall, Tippah90 min
Jun 28, 7:30 PM CDTMesoscale DiscussionSPCDyer, Gibson, Henry, Lake, Obion, Weakley90 min

Nearby

Severe Thunderstorm Watches in Tennessee, 2018Every severe thunderstorm watch in 2018

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.