Alert archive / Tennessee / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 109, NWS Nashville, TN

July 18, 2013Dickson County, Houston County, Humphreys County, Tennessee

NWS Nashville, TN issued this severe thunderstorm warning at Jul 18, 2013, 4:31 PM CDT for Dickson County, Houston County, Humphreys County, Tennessee. It was in force for 44 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 18, 2013, 4:31 PM CDT (21:31 UTC)
Expired: Jul 18, 2013, 5:15 PM CDT
In force: 44 min
Issued by: NWS Nashville, TN
Area: Storm-based polygon

Counties Dickson County, TN, Houston County, TN, Humphreys County, TN

The radar

The Ft Campbell radar (KHPX), 71 km from the middle of the area, began a volume at 21:31 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 12:00Z, 9.5 hours before the alert went out and 91 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: 2137 J/kg
Mixed-layer CIN: -37 J/kg
Mixed-layer LCL: 914 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 35 m²/s²
0-3 km storm-relative helicity: 77 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.6

Open this sounding in Storm Lab

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 Jul 18, 4:16 PM CDT, 15 minutes earlier.

Area forecast discussion, Jul 18, 4:16 PM CDT, 15 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
416 PM CDT THU JUL 18 2013

.MESOSCALE UPDATE...
SCATTERED CONVECTION ACROSS THE NORTH WORKING WESTWARD ON THE
NORTHERN PERIPHERY OF UPPER LEVEL LOW CENTERED DOWN ALONG GULF
COAST. STORMS THIS AFTERNOON FOR THE MOST PART HAVE BEEN
STRONG TO MARGINALLY SEVERE. EXPECT STORMS TO CONTINUE MOVING
WESTWARD OVER THE NEXT COUPLE OF HOURS THEN BEGIN DISSIPATING AS
DIURNAL HEATING DIES OFF.

BOYD

&&

.PREV DISCUSSION... /ISSUED 258 PM CDT THU JUL 18 2013/

DISCUSSION...SCATTERED THUNDERSTORMS WERE OCCURRING MAINLY ACROSS
THE NORTH HALF OF MID TN THIS AFTERNOON...ALONG A MAX CAPE AXIS
WITH MIXED LAYER VALUES OVER 3 KJ/KG. THIS AREA WILL CONTINUE TO
HAVE THE BEST CHANCE FOR THUNDERSTORMS INTO THE EVENING. STORMS
HAVE BEEN PRODUCING VERY HEAVY RAINFALL...NEARLY CONTINUOUS
LIGHTNING AND A COUPLE OF ISOLATED WIND/HAIL REPORTS. THIS
DIURNALLY DRIVEN ACTIVITY...WITH UNUSUAL EAST TO WEST
MOVEMENT...WILL END BY 10 PM OR SO. SOME AREAS THAT RECEIVED THE
HEAVIEST DOWNPOURS MAY SEE SOME PATCHY FOG OVERNIGHT.

HIGH TODAY WERE NOT QUITE AS HIGH AS EXPECTED IN SOME AREAS THANKS
TO THE SCATTERED STORMS AND EXTRA CLOUD COVER. COVERAGE OF STORMS
AND CLOUDS IS EXPECTED TO BE A LITTLE LESS TOMORROW...SO WE WILL
CONTINUE TO FORECAST HIGHS IN THE LOW TO MID 90S...WITH HEAT INDEX
VALUES REACHING 100+ FOR MUCH OF THE AREA.

FOR THE WEEKEND...THE HOT RIDGE OVER THE REGION WILL BREAK DOWN.
DEVELOPING NORTHWEST FLOW ALOFT WILL CAUSE A FRONT TO DROP ACROSS
THE OHIO VALLEY. THIS FRONT WILL NOT MAKE IT THROUGH MID TN...BUT
MOISTURE WILL POOL SOUTH OF THE BOUNDARY BRINGING A GOOD CHANCE
FOR THUNDERSTORMS...ESPECIALLY SATURDAY NIGHT THROUGH SUNDAY.
CONDITIONS WILL REMAIN WARM AND HUMID...BUT THE STORMS AND EXTRA
CLOUD COVER WILL LIMIT HIGHS TO THE LOWER 90S MOST AREAS...AND
HEAT INDEX VALUES SHOULD STAY BELOW 100 THIS WEEKEND.

FOR NEXT WEEK...THE FRONT WILL GRADUALLY DISSOLVE ALLOWING POPS TO
DROP BACK INTO THE 20-30 PERCENT RANGE. THE UPPER LEVEL PATTERN
WILL FEATURE A RIDGE TO OUR WEST...WITH NORTHWEST FLOW CLIPPING
MID TN. IT WILL BE WARM AND HUMID...BUT NOT AS HOT AS THIS WEEK.
ANOTHER BOUNDARY IS EXPECTED TO COME DOWN AND ENHANCE
THUNDERSTORMS CHANCES BY MIDWEEK. THAT FRONT IS ALSO EXPECTED TO
DISSIPATE WITH NO SUBSTANTIAL AIR MASS CHANGE EXPECTED.

13

&&

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

01

Hazardous weather outlook, Jul 18, 5:22 AM CDT, 11 hours 9 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NASHVILLE TN
522 AM CDT THU JUL 18 2013

TNZ005>011-022>034-056>066-075-077>080-093>095-191030-
STEWART-MONTGOMERY-ROBERTSON-SUMNER-MACON-CLAY-PICKETT-BENTON-
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-
522 AM CDT THU JUL 18 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR MIDDLE TENNESSEE.

.DAY ONE...TODAY AND TONIGHT.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

ROSE

In the hours before

Local storm report, Jul 18, 3:53 PM CDT, 38 minutes before

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Special weather statement, Jul 18, 3:57 PM CDT, 34 minutes before

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Local storm report, Jul 18, 4:01 PM CDT, 30 minutes before

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<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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Local storm report, Jul 18, 4:06 PM CDT, 25 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TN
406 PM CDT THU JUL 18 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0310 PM     TSTM WND DMG     3 SE BERRY HILL         36.10N  86.73W
07/18/2013                   DAVIDSON           TN   TWITTER

            TREE SNAPPED AND POWER LINE DOWN ON BRIGGS AVENUE IN
            SOUTH NASHVILLE

&&

EVENT NUMBER OHX1300603

SHAMBURGER

Special weather statement, Jul 18, 4:18 PM CDT, 13 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
418 PM CDT THU JUL 18 2013

TNZ011-033-034-182200-
FENTRESS-OVERTON-PICKETT-
418 PM CDT THU JUL 18 2013

...SIGNIFICANT WEATHER ADVISORY FOR FENTRESS...OVERTON AND PICKETT
COUNTIES...

AT 415 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A STRONG THUNDERSTORM NEAR JAMESTOWN...MOVING WEST AT 15 MPH.

SOME LOCATIONS IN THE PATH INCLUDE ALLARDT...JAMESTOWN...GRIMSLEY AND
CRAWFORD.

PENNY SIZE HAIL...AND WINDS AROUND 50 MPH ARE EXPECTED WITH THIS
STORM.

LAT...LON 3636 8470 3637 8472 3634 8473 3633 8477
      3629 8479 3629 8487 3618 8490 3616 8502
      3617 8503 3614 8513 3615 8520 3617 8524
      3655 8529 3658 8527 3653 8473 3640 8466

BOYD

Special weather statement, Jul 18, 4:22 PM CDT, 9 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NASHVILLE TN
422 PM CDT THU JUL 18 2013

TNZ023>025-182200-
DICKSON-HOUSTON-HUMPHREYS-
422 PM CDT THU JUL 18 2013

...SIGNIFICANT WEATHER ADVISORY FOR DICKSON...HOUSTON AND HUMPHREYS
COUNTIES...

AT 420 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
A STRONG THUNDERSTORM NEAR WHITE BLUFF...MOVING WEST AT 20 MPH.

SOME LOCATIONS IN THE PATH INCLUDE WHITE BLUFF...BURNS...CHARLOTTE...
DICKSON AND VANLEER.

PENNY SIZE HAIL...AND WINDS AROUND 50 MPH ARE EXPECTED WITH THIS
STORM...ALONG WITH FREQUENT LIGHTNING STRIKES.

LAT...LON 3626 8718 3624 8719 3625 8718 3623 8717
      3621 8719 3619 8717 3619 8715 3617 8715
      3616 8717 3607 8717 3603 8719 3599 8762
      3634 8759

BOYD

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 18, 12:06 PM CDT	Special Weather Statement	OHX	Overton	30 min
Jul 18, 1:02 PM CDT	Special Weather Statement	OHX	Clay, Fentress, Jackson, Overton, Pickett, Putnam	43 min
Jul 18, 1:40 PM CDT	Special Weather Statement	OHX	Smith	35 min
Jul 18, 1:47 PM CDT	Special Weather Statement	OHX	Benton, Dickson, Houston, Humphreys, Stewart	43 min
Jul 18, 1:52 PM CDT	Special Weather Statement	OHX	Clay, Overton, Pickett	23 min
Jul 18, 2:17 PM CDT	Special Weather Statement	OHX	Smith, Trousdale, Wilson	43 min
Jul 18, 2:51 PM CDT	Special Weather Statement	OHX	Davidson	39 min
Jul 18, 3:25 PM CDT	Special Weather Statement	OHX	Fentress, Overton, Pickett	50 min
Jul 18, 3:33 PM CDT	Special Weather Statement	OHX	Cheatham, Davidson, Dickson, Williamson	42 min
Jul 18, 3:57 PM CDT	Special Weather Statement	OHX	Benton, Houston, Humphreys, Montgomery, Stewart	48 min
Jul 18, 4:18 PM CDT	Special Weather Statement	OHX	Fentress, Pickett	42 min
Jul 18, 4:22 PM CDT	Special Weather Statement	OHX	Dickson	38 min
Jul 18, 4:54 PM CDT	Special Weather Statement	OHX	Montgomery	51 min
Jul 18, 5:10 PM CDT	Severe Thunderstorm Warning	OHX	Houston, Montgomery, Stewart	50 min
Jul 18, 5:42 PM CDT	Severe Thunderstorm Warning	OHX	Benton, Houston, Humphreys, Montgomery, Stewart	63 min

Nearby

Severe Thunderstorm Warnings in Tennessee, 2013 Every severe thunderstorm warning in 2013

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.