Alert archive / Tennessee / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 34, NWS Nashville, TN

May 5, 2018Coffee County, Warren County, Tennessee

NWS Nashville, TN issued this severe thunderstorm warning at May 5, 2018, 12:43 PM CDT for Coffee County, Warren County, Tennessee. It was in force for 22 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: May 5, 2018, 12:43 PM CDT (17:43 UTC)
Expired: May 5, 2018, 1:05 PM CDT
In force: 22 min
Issued by: NWS Nashville, TN
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Coffee County, TN, Warren County, TN

The radar

The Northeast Alabama radar (KHTX), 76 km from the middle of the area, began a volume at 17:45 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 5.7 hours before the alert went out and 86 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: 277 J/kg
Mixed-layer CIN: -27 J/kg
Mixed-layer LCL: 453 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: -48 m²/s²
0-3 km storm-relative helicity: 81 m²/s²
Significant tornado parameter: -0.1
Supercell composite: -0.7

Open this sounding in Storm Lab

The text

As transmitted.

581 
WUUS54 KOHX 051743
SVROHX
TNC031-177-051830-
/O.NEW.KOHX.SV.W.0034.180505T1743Z-180505T1830Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Nashville TN
1243 PM CDT SAT MAY 5 2018

The National Weather Service in Nashville has issued a

* Severe Thunderstorm Warning for...
  Northeastern Coffee County in Middle Tennessee...
  Western Warren County in Middle Tennessee...

* Until 130 PM CDT.

* At 1243 PM CDT, a severe thunderstorm was located 9 miles northeast
  of Manchester, moving northeast at 20 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  McMinnville, Morrison, Centertown and Summitville. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3552 8598 3558 8603 3579 8589 3560 8567
TIME...MOT...LOC 1743Z 229DEG 18KT 3556 8595 

HAIL...1.00IN
WIND...60MPH
 
$$

Whitehead

1 follow-up statement

090 
WWUS54 KOHX 051805
SVSOHX

Severe Weather Statement
National Weather Service Nashville TN
105 PM CDT SAT MAY 5 2018

TNC031-177-051815-
/O.CAN.KOHX.SV.W.0034.000000T0000Z-180505T1830Z/
Coffee TN-Warren TN-
105 PM CDT SAT MAY 5 2018

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN COFFEE AND
WESTERN WARREN COUNTIES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore the warning has been cancelled.  However small hail is
still possible with this thunderstorm.

LAT...LON 3552 8598 3558 8603 3579 8589 3560 8567
TIME...MOT...LOC 1802Z 229DEG 18KT 3563 8585 

$$

Whitehead

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Nashville, TN wrote its last area forecast discussion before this severe thunderstorm warning went out at May 5, 11:19 AM CDT, 1 hour 24 minutes earlier.

Area forecast discussion, May 5, 11:19 AM CDT, 1 hour 24 minutes before

Area Forecast Discussion
National Weather Service Nashville TN
1119 AM CDT Sat May 5 2018

.UPDATE...
FOR MORNING DISCUSSION.

&&

.DISCUSSION...

Late this morning, some fairly strong thunderstorms had developed
across Giles County and surrounding areas. The storms had formed
in an area of 30-35KT low level bulk shear with 500-1000 J/kg
cape. As the low pressure and cold front continue to move east,
it looks like the best combination of cape reaching 1000 and 35KT
bulk shear will shift east northeast through the next couple of
hours. So, we will have to watch areas around Shelbyville,
Manchester, Woodbury, and possibly up to Murfreesboro for some
strong storms and perhaps a couple of marginally severe storms
with wind gust and hail potential. That axis will move on up to
Cookeville and Crossville by mid afternoon.

&&

.AVIATION...
12Z TAF DISCUSSION.

Deteriorating flight conditions will be the story at all mid-state
terminals through the morning and into the afternoon hours. VFR
will become MVFR by late this morning, then IFR this evening as
the upper low swings overhead. Brief IFR vis is likely with any
heavier rains. VFR should return after 06Z for KCKV/KBNA/KMQY, but
IFR will likely hold firm at KCSV into Sunday morning.

Northerly winds will be light (10 kts or less) throughout the
cycle.

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

DISCUSSION......13
AVIATION........Unger

Hazardous weather outlook, May 5, 11:35 AM CDT, 1 hour 8 minutes before

Hazardous Weather Outlook
National Weather Service Nashville TN
1135 AM CDT Sat May 5 2018

TNZ005>011-023>034-056>066-075-077>080-093>095-061645-
Stewart-Montgomery-Robertson-Sumner-Macon-Clay-Pickett-Houston-
Humphreys-Dickson-Cheatham-Davidson-Wilson-Trousdale-Smith-
Jackson-Putnam-Overton-Fentress-Perry-Hickman-Lewis-Williamson-
Maury-Marshall-Rutherford-Cannon-De Kalb-White-Cumberland-Bedford-
Coffee-Warren-Grundy-Van Buren-Wayne-Lawrence-Giles-
1135 AM CDT Sat May 5 2018

This Hazardous Weather Outlook is for portions of Middle
Tennessee.

.DAY ONE...This Afternoon and Tonight

A few strong thunderstorms with wind gusts around 40 mph and small
hail are possible through the afternoon for southeastern areas of
the Mid State. This includes Shelbyville, Manchester,
McMinnville, and perhaps as far north as Cookeville and
Crossville. One or two of the thunderstorms could become briefly
severe with gusty winds and hail.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Any reports of strong winds or hail would be appreciated.

13

In the hours before

Special weather statement, May 5, 10:42 AM CDT, 2 hours 1 minute before

Special Weather Statement
National Weather Service Nashville TN
1042 AM CDT SAT MAY 5 2018

TNZ095-051615-
Giles TN-
1042 AM CDT SAT MAY 5 2018

...SIGNIFICANT WEATHER ADVISORY FOR EAST CENTRAL GILES COUNTY UNTIL
1115 AM CDT...

At 1042 AM CDT, Doppler radar was tracking a strong thunderstorm near
Pulaski, moving northeast at 15 mph.

Half inch hail and winds in excess of 30 mph will be possible with
this storm.

Locations impacted include...
Pulaski and Frankewing.

LAT...LON 3519 8704 3535 8692 3535 8691 3534 8691
      3534 8690 3532 8691 3531 8691 3531 8687
      3530 8686 3532 8685 3529 8683 3517 8683
      3512 8698
TIME...MOT...LOC 1542Z 227DEG 12KT 3517 8699

Whitehead

Special weather statement, May 5, 11:39 AM CDT, 1 hour 4 minutes before

Special Weather Statement
National Weather Service Nashville TN
1139 AM CDT SAT MAY 5 2018

TNZ077-051715-
Coffee TN-
1139 AM CDT SAT MAY 5 2018

...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL COFFEE COUNTY UNTIL 1215
PM CDT...

At 1138 AM CDT, Doppler radar was tracking a strong thunderstorm near
Tullahoma, or near Manchester, moving northeast at 20 mph.

Dime size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Manchester, Tullahoma and Summitville.

LAT...LON 3534 8620 3539 8625 3539 8627 3541 8625
      3541 8626 3542 8625 3545 8625 3545 8624
      3546 8625 3566 8614 3566 8612 3552 8588
      3550 8588
TIME...MOT...LOC 1638Z 227DEG 18KT 3543 8617

Whitehead

The office that day

Everything else NWS Nashville, TN issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 5, 10:42 AM CDT	Special Weather Statement	OHX	Giles	33 min
May 5, 11:39 AM CDT	Special Weather Statement	OHX	Coffee	36 min
May 5, 12:07 PM CDT	Severe Thunderstorm Warning	OHX	Coffee, Warren	38 min
May 5, 1:12 PM CDT	Special Weather Statement	OHX	Coffee, Grundy, Warren	48 min
May 5, 1:38 PM CDT	Special Weather Statement	OHX	DeKalb	52 min
May 5, 2:13 PM CDT	Special Weather Statement	OHX	Putnam	32 min
May 5, 2:35 PM CDT	Special Weather Statement	OHX	Fentress, Overton, Pickett	55 min
May 5, 3:05 PM CDT	Severe Thunderstorm Warning	OHX	Fentress, Overton, Pickett	25 min
May 5, 3:29 PM CDT	Special Weather Statement	OHX	Pickett	31 min

Nearby

Severe Thunderstorm Warnings in Tennessee, 2018 Every severe thunderstorm warning 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.