Alert archive / Florida / Flash Flood Warnings in 1998

Flash Flood Warning 47, NWS Jacksonville, FL

July 15, 1998Suwannee County, Florida

NWS Jacksonville, FL issued this flash flood warning at Jul 15, 1998, 7:18 PM EDT for Suwannee County, Florida. It was in force for 2 hr. 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 15, 1998, 7:18 PM EDT (23:18 UTC)
Expired: Jul 15, 1998, 9:20 PM EDT
In force: 2 hr
Issued by: NWS Jacksonville, FL
Area: Whole counties

County Suwannee County, FL

The nearest sounding before it

Jacksonville, FL (KJAX), launched 12:00Z, 11.3 hours before the alert went out and 128 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: 283 J/kg
Mixed-layer CIN: -45 J/kg
Mixed-layer LCL: 665 m above ground
0-6 km bulk shear: 7 kt
0-1 km storm-relative helicity: -20 m²/s²
0-3 km storm-relative helicity: 4 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.

000 
TTAA00 KJAX 152320
FFWJAX
FLC121-160120-

BULLETIN - EAS ACTIVATION REQUESTED
FLOOD WARNING
NATIONAL WEATHER SERVICE JACKSONVILLE FL
718 PM EDT WED JUL 15 1998

THE NATIONAL WEATHER SERVICE IN JACKSONVILLE HAS ISSUED A

* FLOOD WARNING FOR...
  SUWANNEE COUNTY COUNTY IN NORTHERN FLORIDA

* UNTIL 920 PM EDT

* AT 716 PM DOPPLER RADAR WAS INDICATING 2 TO 4 INCH AMOUNTS OF RAIN
  HAD FALLEN SINCE LATE AFTERNOON OVER MANY PARTS OF THE COUNTY. THE
  HIGHEST AMOUNTS INDICATED ON RADAR OF OVER 4 INCHES JUST SOUTH OF LIVE
  OAK. ADDITIONAL HEAVY SHOWERS AND THUNDERSTORMS WILL CONTINUE THIS
  EVENING...SO A FLOOD WARNING IS IN EFFECT.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING.

AREA RESIDENTS SHOULD MONITOR FLOOD CONDITIONS... AND BE PREPARED
TO MOVE TO HIGHER GROUND... SHOULD FLOOD WATERS THREATEN. IF
FLOODING IS OBSERVED... ACT QUICKLY. MOVE TO HIGHER GROUND TO
ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS SUBJECT TO FLOODING WHEN
WATER BEGINS RISING.

MOHLIN

What forecasters said that day

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

NWS Jacksonville, FL wrote its last area forecast discussion before this flash flood warning went out at Jul 15, 3:50 PM EDT, 3 hours 28 minutes earlier.

Area forecast discussion, Jul 15, 3:50 PM EDT, 3 hours 28 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSONVILLE FL
230 PM  EDT WED JUL 15 1998

SFC LOW OVER S GA SLOWLY LIFTING NORTH FROM NEAR AYS...A BIT FASTER THAN
PROGGED.  NORTHWEST FLOW PUNCHING INTO NORTH SUWANNEE VALLEY SETTING UP
A CONVERGENCE LINE FROM BIG BEND TO JAX ALONG THE STATE LINE WITH STRONG
SOUTHWEST FLOW TO SOUTH AS EXPECTED.  THIS WILL SET UP STRONG MOIST FLOW
ACROSS THE NECK OF FL PENINSULA AND  CONTINUE DESTABILIZING NE FL AND SE
GA WHERE STRONG DIURNAL HEATING IN PLACE UNDER CLEAR SKY. WITH TEMPS NOW
NEAR 90 OVER AREA CAPE IS IN VICINITY OF 2500 J/KG...WITH HIGH PRECIP
WATER.  ANTICIPATE MAJOR RAIN EVENT BREAKING OUT WITH WIDESPREAD 2 INCH
AND SOME 4 PLUS TOTALS LIKELY.  EVENT WILL CONTINUE INTO NIGHT.
EXPECT INCREASED WINDS TO REMAIN AT OR ABOVE 15 KTS OVERNIGHT INTO FRIDAY.
DO NOT EXPECT GRADIENT TO WEAKEN AS LOW IS ESSENTIALLY TROPICAL OVER LAND
AND GAINING LATENT HEAT FROM PM RAINS.  COASTAL GA FLOODING POSSIBLE.
JAX TR 75/95 75/96 73 13795
GNV TR 72/92 74/95 74 13674
SSI TT 76/88 76/92 75 13995
WELSH

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 15, 5:51 PM EDT	Severe Thunderstorm Warning	JAX	Nassau	64 min

Nearby

Flash Flood Warnings in Florida, 1998 Every flash flood 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.