Alert archive / Tennessee / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 158, NWS Nashville, TN

April 30, 1998Grundy County, Tennessee

NWS Nashville, TN issued this severe thunderstorm warning at Apr 30, 1998, 5:48 PM CDT for Grundy County, Tennessee. It was in force for 32 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: Apr 30, 1998, 5:48 PM CDT (22:48 UTC)
Expired: Apr 30, 1998, 6:20 PM CDT
In force: 32 min
Issued by: NWS Nashville, TN
Area: Whole counties

County Grundy County, TN

What was reported inside it

Time	Report	Where	Remark
Apr 30, 6:10 PM CDT	Thunderstorm Wind 50	Altamont, TN	Sheriff's office reported a tree down on Northcutts Cove Road.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 10.8 hours before the alert went out and 114 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: 313 J/kg
Mixed-layer CIN: -2 J/kg
Mixed-layer LCL: 493 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 264 m²/s²
0-3 km storm-relative helicity: 286 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

281 
WUUS1 KBNA 302249 RRA
SVRBNA
TNC061-302320-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NASHVILLE TN
548 PM CDT THU APR 30 1998

THE NATIONAL WEATHER SERVICE IN NASHVILLE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  GRUNDY COUNTY IN SOUTHEASTERN TENNESSEE

* UNTIL 620 PM CDT

* AT 545 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM NEAR ALTAMONT... MOVING NORTHEAST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  BEERSHEBA SPRINGS AT 553 PM CDT
  SAVAGE GULF PARK AT 557 PM CDT
  TARLTON AT 600 PM CDT

DAMAGING WINDS AND LARGE HAIL ARE LIKELY. GO INSIDE A STURDY
BUILDING AND STAY AWAY FROM WINDOWS

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 Apr 30, 2:30 PM CDT, 3 hours 18 minutes earlier.

Area forecast discussion, Apr 30, 2:30 PM CDT, 3 hours 18 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NASHVILLE TN
230 PM CDT THU APR 30 1998

MARGINAL UNSTABLE AIRMASS OVER CWA SHOULD CONTINUE TO SUPPORT SHOWER
AND THUNDERSTORM ACTIVITY INTO THE EVENING HOURS. NGM INITIALIZES
LOW LEVEL MOISTURE FIELD THE BEST AND WILL BE THE MODEL OF CHOICE
FOR FORECAST PERIOD. NGM MOVES LOW PRESSURE FROM SOUTHERN ILLINOIS
INTO EASTERN PORTIONS OF THE OHIO RIVER VALLEY BY THE END OF THE
PERIOD. IT ALSO MOVES SLOW MOVING SURFACE COLD FRONT TO OUR EAST
BY 12Z FRI.SECONDARY COLD FRONT MOVES LATER IN THE DAY AND WILL
BE ASSOCIATED WITH SOME SCATTERED SHOWERS AND THUNDERSTORMS.BREAKAGE IN
THE CLOUD FIELD WILL OCCUR DURING THE DAY ON SATURDAY AS UPPER LEVEL
RIDGE MOVES INTO CWA. HOWEVER...LOOKS LIKE ANOTHER SHORTWAVE WILL MOVE
INTO CWA AFTER 48HRS PROVIDING PRECIPATION CHANCES FOR CWA WITH A MORE
PRONOUCED LOW LEVEL MOISTURE FLOW.

WOULD RECOMMEND THE MENTIONING OF A SLIGHT CHC AT LEAST OVER SOUTHERN
PORTIONS OF CWA FOR FRI DUE TO SECONDARY TROUGH OVER REGION.

THUS...WILL LEAN TOWARD MOS NUMBERS FOR PCPN DURING ALL PDS...WOULD
RECOMMEND HOWEVER VALUES IN THE 20% RANGE FOR FRI NIGHT. WILL
COMPROMISE BETWEEN MOS/FAN VALUES FOR TEMPS FIRST THREE PERIODS
...AND GO CLOSE TO FAN FOR FOURTH.

BNA 53/68/52/74     5521

14
JBW

In the hours before

Local storm report, Apr 30, 4:53 PM CDT, 55 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE NASHVILLE TENNESSEE
453 PM CDT THU APR 30 1998

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0420 PM    MANCHESTER                TN   .75 INCH HAIL
04/30/98   COFFEE                         COFFEE COUNTY SHERIFF
                                          OFFICE REPORTED DIME SIZE
                                          HAIL IN MANCHESTER.

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 30, 4:07 PM CDT	Severe Thunderstorm Warning	OHX	Coffee	63 min
Apr 30, 4:35 PM CDT	Severe Thunderstorm Warning	OHX	Warren	50 min
Apr 30, 6:20 PM CDT	Flash Flood Warning	OHX	Franklin, Grundy, Warren	90 min
Apr 30, 6:20 PM CDT	Flash Flood Warning	OHX	Van Buren	90 min
Apr 30, 6:26 PM CDT	Severe Thunderstorm Warning	OHX	Van Buren	34 min
Apr 30, 6:46 PM CDT	Flash Flood Warning	OHX	Overton, Pickett, Putnam	119 min
Apr 30, 6:46 PM CDT	Flash Flood Warning	OHX	White	119 min

Nearby

Severe Thunderstorm Warnings in Tennessee, 1998 Every severe thunderstorm warning in 1998

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.