Alert archive / Tennessee / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 434, NWS Morristown, TN

July 20, 1998Hamilton County, Tennessee

NWS Morristown, TN issued this severe thunderstorm warning at Jul 20, 1998, 1:30 PM EDT for Hamilton County, Tennessee. It was in force for 60 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 20, 1998, 1:30 PM EDT (17:30 UTC)
Expired
Jul 20, 1998, 2:30 PM EDT
In force
60 min
Issued by
NWS Morristown, TN
Area
Whole counties

County Hamilton County, TN

The nearest sounding before it

Nashville Metro, TN (KBNA), launched 12:00Z, 5.5 hours before the alert went out and 167 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 12:00Z on 1998-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3140 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, Nashville Metro, TN at 12:00Z on 1998-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 55 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
3140 J/kg
Mixed-layer CIN
-64 J/kg
Mixed-layer LCL
987 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
55 m²/s²
0-3 km storm-relative helicity
50 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 Morristown, TN wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 19, 3:06 PM EDT, 22 hours 24 minutes earlier.

Area forecast discussion, Jul 19, 3:06 PM EDT, 22 hours 24 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KNOXVILLE/TRI-CITIES TN
306 PM EDT SUN JUL 19 1998

BNDRY SET UP ACRS ERN KY ERLYR...BETW LO CLDS/CLEARING.  THIS HAS BEEN
SUFFICIENT TO FIRE A QUASISTNRY LINE OF TSTMS...WHICH WITH DRY AIR
ALFT HAVE GREAT POTENTIAL FOR DOWNBURSTS AS THEY COLLAPSE.  WINDEX
FROM MOD SNDG WAS 86 KTS.  ANOTHER THRT FROM THESE STORMS...OWING TO
WEAK UPR WINDS PARALLEL TO BNDRY...IS HEAVY RAIN.  ALREADY SEEING
TRAINING ECHOES AND MORE THAN AN INCH PER HOUR AMTS ON RADAR.
GOOD NEWS IS THAT THIS EVENT APRS TO BE CONFINED TO THE NE PART OF
CWA...ALBEIT BAD NEWS FOR PARCHED LAWNS.

CONVECT SHUD BE DECREASING AFT SUNSET...GIVING WAY TO A WARM HAZY
NIGHT.  COULD BE MUCH MORE DENSE FG IN TRI AREA THAN ANTIC ERLYR...IF
SIGNIF PRECIP FALLS.

TOMORROW SHUD BE A HOT ONE...BLV CHA WILL BE NR 100 F FOR A MAX.
HWVR...OUTFLOW BNDRYS FROM THIS EVE'S CONVECT CUD FIRE ADDL CONVECT
FROM TYS NEWD...COOLING THIS AREA BLO GUID.

SMH

Nearby

Severe Thunderstorm Warnings in Tennessee, 1998Every 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; the sounding from the Mesonet's radiosonde archive.