Alert archive / Florida / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 110, NWS Melbourne, FL

August 18, 2001Orange County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Aug 18, 2001, 4:57 PM EDT for Orange County, Florida. It was in force for 63 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
Aug 18, 2001, 4:57 PM EDT (20:57 UTC)
Expired
Aug 18, 2001, 6:00 PM EDT
In force
63 min
Issued by
NWS Melbourne, FL
Area
Whole counties

County Orange County, FL

The radar

The Melbourne radar (KMLB), 79 km from the middle of the area, began a volume at 20:57 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

TimeReportWhereRemark
Aug 18, 5:30 PM EDTThunderstorm Wind 60 EOrlando, FLThunderstorm winds blew down trees that heavily damaged three cars and the roof of a house.

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

Cape Canaveral, FL (KXMR), launched 12:00Z, 9.0 hours before the alert went out and 81 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, Cape Canaveral, FL at 12:00Z on 2001-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1928 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Cape Canaveral, FL at 12:00Z on 2001-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 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
1928 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
772 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
26 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.

320 
WUUS52 KMLB 182057
SVRMLB
FLC095-182200-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MELBOURNE FL
457 PM EDT SAT AUG 18 2001

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  ORANGE COUNTY
  IN EAST CENTRAL FLORIDA

* UNTIL 600 PM EDT.

* AT 455 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER ORLOVISTA...OR ABOUT 3 MILES SOUTH OF PINE
  HILLS...MOVING LITTLE.  

* THIS STORM WILL BE AFFECTING AREAS AROUND DOWNTOWN ORLANDO. OTHER 
STORMS WERE DEVELOPING RAPDILY ACROSS ORANGE COUNTY AND COULD ALSO 
BECOME SEVERE.

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS IN EXCESS OF 58 MILES AN
HOUR...DESTRUCTIVE HAIL...DEADLY LIGHTNING AND VERY HEAVY RAIN. IF
THE STORM APPROACHES YOU...MOVE TO AN INTERIOR ROOM ON THE LOWEST
FLOOR.

$$

LAT...LON 2865 8144 2853 8159 2836 8135 2842 8111

RL

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 Melbourne, FL wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 18, 2:45 PM EDT, 2 hours 12 minutes earlier.

Area forecast discussion, Aug 18, 2:45 PM EDT, 2 hours 12 minutes before
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
245 PM EDT SAT AUG 18 2001

CURRENTLY...BOTH ATLANTIC AND GULF BREEZES HAVE DEVELOPED AND ARE
MOVING INLAND...QUITE UNDISTURBED BY CONVECTION. THIS SHOULD LEAD TO
MORE OR LESS A TRUE SEA BREEZE COLLISION OVER THE INTERIOR
COUNTIES...NEAR THE ORLANDO METRO AREA OR JUST EAST...LATER THIS
AFTN/EVE. SOME OF THE RESULTING STORMS WILL BE STRONG. UNTIL THEN...
OTHER STORMS...SOME STRONG...WILL DEVELOP AS THE EAST COAST BREEZE
INTERACTS WITH THE LAKE OKEECHOBEE BREEZE (SEEN ON VIS SAT IMAGERY)
AND OTHER LAKE BOUNDARIES.

UPPER TROUGH DEEPENS OVER EASTERN U.S. AND SFC FRONT DROPS INTO THE
DEEP SOUTH DURING THE NEXT 48 HOURS. THIS WILL INCREASE THE SW
GRADIENT FLOW SUN...ESP NORTH HALF...ALLOWING STORMS TO MOVE BACK TO
THE COAST LATE IN THE DAY. AS A RESULT...ALTHOUGH EAST COAST BREEZE
WILL DEVELOP SUNDAY...IT WILL BE HELD CLOSER TO THE COAST THAN TODAY
ESP VOLUSIA COUNTY. WILL CONTINUE 50 POP NORTH COAST FOR LATE
ACTIVITY. 12Z AVN BRINGS A BAND OF DRIER AIR/SUBSIDENCE NORTH INTO
OUR SOUTHERN ZONES SUN AFT. THIS LOOKS REASONABLE LOOKING AT CURRENT
WATER VAPOR IMAGERY AND SPEED OF SYSTEM. EXTENT OF DRYING MAY BE
MORE OR LESS DEPENDING ON STRENGTH OF CHANTAL. SO WILL GO WITH
JUST 30 POPS SOUTHERN ZONES SUN.

CHANTAL IS PROGGED TO STAY WELL SOUTH AND WEST OF THE FORECAST
AREA. HOWEVER...ETA AND AVN BRING DEEP MOISTURE NORTH ACROSS THE
SOUTHERN HALF OF THE PENINSULA MON. AGAIN...EXTENT OF MOISTURE
ADVECTION WILL DEPEND ON STRENGTH OF THE SYSTEM. BUT MODEL RUN TO
RUN CONSISTENCY HAS INCREASED OUR CONFIDENCE THAT HIGHER POPS ARE IN
ORDER MON FOR SOUTHERN ZONES (50%)...BUT BAND OF SUBSIDENCE MOVING
UP THE PENINSULA SHOULD KEEP POPS LOWER ELSEWHERE.

EXTENDED FORECAST IS HIGHLY DEPENDENT ON TRACK AND INTENSITY OF
CHANTAL. MOST MODELS (NOGAPS, UKMET, GFDL) ARE IN AGREEMENT WITH
BRINGING THE SYSTEM INTO THE WESTERN GULF OF MEXICO EARLY NEXT
WEEK...BUT MRF/AVN ARE DECIDEDLY MORE EASTWARD AND PULLING DEEP
MOISTURE OVER THE PENINSULA TUE AND WED. WILL CONTINUE TO DISCOUNT
THIS SOLUTION FOR NOW...AND KEEP SCT POPS IN THE EXTENDED.

MARINE...A FEW STORMS MAY MOVE OFF THE PENINSULA THIS EVENING NORTH
OF THE CAPE...WITH A BETTER CHANCE SUN. MORE WIDESPREAD CONVECTION
MAY DEVELOP NORTHWARD INTO THE SOUTHERN WATERS MON. SEAS TO REMAIN
PRETTY FLAT WITH PRIMARILY A SMALL EAST SWELL.

PRELIM...
DAB BB 075/094 074/092 073 3534
MCO BB 075/093 075/092 075 3424
MLB BB 076/091 076/090 075 -524

.MLB...NONE.

PUBLIC/MARINE...KELLY
AVIATION/FIRE WX...BRAGAW

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 18, 5:16 PM EDTSevere Thunderstorm WarningMLBVolusia44 min
Aug 18, 5:23 PM EDTSevere Thunderstorm WarningMLBSeminole37 min

Nearby

Severe Thunderstorm Warnings in Florida, 2001Every severe thunderstorm warning in 2001

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.