Alert archive / Florida / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 21, NWS Jacksonville, FL

April 23, 1997Columbia County, Suwannee County, Florida

NWS Jacksonville, FL issued this severe thunderstorm warning at Apr 23, 1997, 7:38 AM EDT for Columbia County, Suwannee County, Florida. It was in force for 37 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 23, 1997, 7:38 AM EDT (11:38 UTC)
Expired: Apr 23, 1997, 8:15 AM EDT
In force: 37 min
Issued by: NWS Jacksonville, FL
Area: Whole counties

Counties Columbia County, FL, Suwannee County, FL

The radar

The Moody AFB radar (KVAX), 78 km from the middle of the area, began a volume at 11:39 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 was reported inside it

Time	Report	Where	Remark
Apr 23, 7:38 AM EDT	Thunderstorm Wind	Live Oak, FL	Two farm buildings destroyed.

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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 23, 3:00 AM EDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Jacksonville, FL (KJAX), launched 00:00Z, 11.6 hours before the alert went out and 111 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: 814 J/kg
Mixed-layer CIN: -147 J/kg
Mixed-layer LCL: 1303 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 123 m²/s²
0-3 km storm-relative helicity: 147 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.7

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KJAX 231138 RRA
SVRJAX
FLC023-121-231215-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE JACKSONVILLE FL
738 AM EDT WED APR 23 1997
 
THE NATIONAL WEATHER SERVICE IN JACKSONVILLE HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  815 AM EDT
FOR PERSONS IN THE FOLLOWING LOCATIONSS...
 
IN NORTH FLORIDA
 
   ...SOUTHERN COLUMBIA COUNTY...SOUTHERN SUWANNEE COUNTY
 
AT 735 AM EDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATES A SEVERE
THUNDERSTORM MOVING EASTWARD ACROSS SOURTHERN SUWANNEE COUNTY. THIS
STORM WILL MOVE EAST SOUTH OF INTERSTATEE 10 INTO THE AND LAKE CITY AREA
BY 8 AM.
 
A TORNADO WATCH IS ALSO IN EFFECT FOR THE WARNED AREA.  REMEMBER
SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES
WITH LITTLE OR NO ADVANCE WARNING.  REMAIN CALM BUT BE ALERT TO
RAPIDLY CHANGING WEATHER CONDITIONS.
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADzLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.
 
SANDRIK

The office that day

Everything else NWS Jacksonville, FL issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 23, 4:59 AM EDT	Tornado Warning	JAX	Nassau	31 min
Apr 23, 5:29 AM EDT	Severe Thunderstorm Warning	JAX	Duval	61 min
Apr 23, 7:29 AM EDT	Severe Thunderstorm Warning	JAX	Clay	31 min
Apr 23, 7:46 AM EDT	Severe Thunderstorm Warning	JAX	Saint Johns	44 min
Apr 23, 7:57 AM EDT	Tornado Warning	JAX	Clay, Putnam	33 min
Apr 23, 8:13 AM EDT	Tornado Warning	JAX	Alachua	47 min
Apr 23, 8:31 AM EDT	Tornado Warning	JAX	Bradford, Clay	59 min
Apr 23, 8:43 AM EDT	Flash Flood Warning	JAX	Alachua	4 hr
Apr 23, 9:41 AM EDT	Severe Thunderstorm Warning	JAX	Flagler	49 min
Apr 23, 9:56 AM EDT	Tornado Warning	JAX	Marion	64 min
Apr 23, 10:08 AM EDT	Flash Flood Warning	JAX	Putnam	4 hr
Apr 23, 10:31 AM EDT	Severe Thunderstorm Warning	JAX	Flagler	29 min
Apr 23, 11:39 AM EDT	Severe Thunderstorm Warning	JAX	Alachua	36 min
Apr 23, 11:50 AM EDT	Severe Thunderstorm Warning	JAX	Clay	40 min

Nearby

Severe Thunderstorm Warnings in Florida, 1997 Every severe thunderstorm warning in 1997

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; radar from the NEXRAD Level II archive.