Alert archive / Florida / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 68, NWS Melbourne, FL

July 31, 2019Okeechobee County, Florida

NWS Melbourne, FL issued this severe thunderstorm warning at Jul 31, 2019, 2:15 PM EDT for Okeechobee County, Florida. It was in force for 31 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 31, 2019, 2:15 PM EDT (18:15 UTC)
Expired
Jul 31, 2019, 2:46 PM EDT
In force
31 min
Issued by
NWS Melbourne, FL
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Okeechobee County, FL

The radar

The Melbourne radar (KMLB), 97 km from the middle of the area, began a volume at 18:14 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Cape Canaveral, FL (KXMR), launched 12:00Z, 6.3 hours before the alert went out and 139 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 2019-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2731 joules per kilogram.LCLEL10008507005003002001001 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, Cape Canaveral, FL at 12:00Z on 2019-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 11 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
2731 J/kg
Mixed-layer CIN
-3 J/kg
Mixed-layer LCL
734 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
11 m²/s²
0-3 km storm-relative helicity
20 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

173 
WUUS52 KMLB 311815
SVRMLB
FLC093-311900-
/O.NEW.KMLB.SV.W.0068.190731T1815Z-190731T1900Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Melbourne FL
215 PM EDT Wed Jul 31 2019

The National Weather Service in Melbourne has issued a

* Severe Thunderstorm Warning for...
  South central Okeechobee County in east central Florida...

* Until 300 PM EDT.

* At 214 PM EDT, a severe thunderstorm was located near Okeechobee,
  and is drifting northwest at 5 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Okeechobee, Whispering Pines, Basswood Estates and Okeechobee
  Airport.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 2720 8088 2728 8100 2730 8100 2730 8102
      2731 8101 2739 8092 2728 8080
TIME...MOT...LOC 1814Z 107DEG 4KT 2728 8090 

HAIL...1.00IN
WIND...60MPH
 
$$

Glitto
2 follow-up statements
284 
WWUS52 KMLB 311834
SVSMLB

Severe Weather Statement
National Weather Service Melbourne FL
234 PM EDT Wed Jul 31 2019

FLC093-311900-
/O.CON.KMLB.SV.W.0068.000000T0000Z-190731T1900Z/
Okeechobee FL-
234 PM EDT Wed Jul 31 2019

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR SOUTH CENTRAL OKEECHOBEE COUNTY...

At 233 PM EDT, a severe thunderstorm was located about 7 miles 
southeast of Basinger, moving northwest at 10 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
Basswood Estates.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 2722 8091 2728 8100 2730 8100 2730 8102
      2731 8101 2739 8092 2728 8085
TIME...MOT...LOC 1833Z 142DEG 9KT 2732 8094 

HAIL...1.00IN
WIND...60MPH
 
$$

Glitto
687 
WWUS52 KMLB 311846
SVSMLB

Severe Weather Statement
National Weather Service Melbourne FL
246 PM EDT Wed Jul 31 2019

FLC093-311856-
/O.CAN.KMLB.SV.W.0068.000000T0000Z-190731T1900Z/
Okeechobee FL-
246 PM EDT Wed Jul 31 2019

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL OKEECHOBEE
COUNTY IS CANCELLED...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning has
been cancelled.  However gusty winds are still possible with this
thunderstorm.

LAT...LON 2722 8091 2728 8100 2730 8100 2730 8102
      2731 8101 2739 8092 2728 8085
TIME...MOT...LOC 1845Z 107DEG 4KT 2732 8096 

$$

Glitto

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 Jul 31, 9:15 AM EDT, 5 hours earlier.

Area forecast discussion, Jul 31, 9:15 AM EDT, 5 hours before
East Central Florida Forecast Discussion
National Weather Service Melbourne FL
915 AM EDT Wed Jul 31 2019

.DISCUSSION...
Currently...Moisture has increased to around 2.0 inches on the
morning sounding data from the cape. A very light wind profile
remains in place making a challenge for specific rainfall coverage
during the day. Using a forecast of numerous boundary interactions
from mid to late afternoon, rainfall chances have been increased
inland from the immediate coast on today's forecast.

Today-Tonight...Good surface based heating will lead to the
development of an east coast sea breeze boundary by mid day, and a
late afternoon sea breeze collision is expected over the central
peninsula. The lowest rain chances will be along the east coast and
beaches (around 30 percent) and highest across the interior (40-50
percent). The main threat with storms will be dangerous cloud to
ground lightning strikes and heavy downpours. A few storms may
produce wind gusts up to 40 to 45 mph.

By nightfall, most of the convection will be west of our area,
though some showers and storms may be lingering from Lake County
south along the Kissimmee River towards Lake Okeechobee. These
storms are forecast to dissipate within an hour or two after sunset.
Interestingly, about half of the high resolution models indicate
convection may blow back east across parts of Orange and Osceola
Counties and into Brevard late this evening. While the situation
will not evolve exactly as currently depicted, we could see a few
showers/storms push their way back into the area after sunset.
Otherwise, skies will clear tonight with overnight lows settling
into the mid to upper 70s.

&&

.AVIATION...
VFR conditions will prevail through mid day. Showers and
thunderstorms will develop along the inland advancing sea breeze.
The main impacts from storms will most likely be seen at MCO,
SFB, LEE, and ISM between 18Z-22Z this afternoon, and vicinity
storms at DAB and TIX possible from 17Z-20Z. Storms will be
capable of producing IFR visibilities and MVFR ceiling conditions
for short periods of time. The sea breeze will advance inland
quickly from MLB to SUA, so those terminals should remain clear.

&&

.MARINE...
Today-Tonight...Light southeast winds this morning will become
onshore at around 10 knots by this afternoon as the Atlantic high
pressure builds over the area. Generally favorable boating
conditions with seas 1-2 feet nearshore, and 2-3 feet offshore.
Scattered showers and storms will be possible through the late
morning before clearing out by early afternoon.

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.

&&

JP/PG
Hazardous weather outlook, Jul 31, 10:19 AM EDT, 3 hours 56 minutes before
Hazardous Weather Outlook
National Weather Service Melbourne FL
1019 AM EDT Wed Jul 31 2019

AMZ550-552-555-570-572-575-FLZ041-044>047-053-054-058-059-064-141-
144-147-312300-
Flagler Beach to Volusia-Brevard County Line 0-20 nm-Volusia-
Brevard County Line to Sebastian Inlet 0-20 nm-
Sebastian Inlet to Jupiter Inlet 0-20 nm-Flagler Beach to Volusia-
Brevard County Line 20-60 nm-Volusia-
Brevard County Line to Sebastian Inlet 20-60 nm-
Sebastian Inlet to Jupiter Inlet 20-60 nm-Inland Volusia-
Northern Lake-Orange-Seminole-Southern Brevard-Osceola-
Indian River-Okeechobee-St. Lucie-Martin-Coastal Volusia-
Southern Lake-Northern Brevard-
1019 AM EDT Wed Jul 31 2019

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST CENTRAL FLORIDA.

.DAY ONE...TODAY AND TONIGHT.

.THUNDERSTORM IMPACT...
Scattered lightning storms will develop over the coastal counties
as the east coast sea breeze develops. Storms will increase
through the afternoon over the interior counties as the sea breeze
pushes inland, and will continue into the early evening hours.
Frequent lightning and heavy rain will be the primary hazards, but
some storms will also be capable of wind gusts up to 45 mph over
the interior counties as the east and west coast sea breezes
merge. If threatening weather develops or if thunder is heard,
cease outdoor activities and seek shelter in an enclosed building.

.FLOOD IMPACT...
Locally heavy downpours of 1 to 2 inches of rain in a short
duration may accompany some storms today, especially inland where
multiple boundaries interact. This could lead to ponding of water
on roadways, parking lots, and other poorly drained and low-lying
areas.

.RIP CURRENT IMPACT...
A 2 foot long period swell will combine with a high astronomical
tide to generate a moderate rip current threat along the beaches
of east central Florida. The threat will be highest from Noon through
5 PM this afternoon due to tidal effects. Always swim within site
of a lifeguard, and never swim alone.

.MARINE THUNDERSTORM GUST IMPACT...
Storms will be capable of wind gusts over 35 knots mainly over
large inland lakes today but also the Intracoastal Waterway and
nearshore Atlantic waters early this afternoon.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.
Scattered to numerous showers and lightning storms are expected
each day with higher storm coverage over the interior. The main
storm hazards will continue to be dangerous cloud to ground
lightning strikes, strong wind gusts and local heavy rain. Rain
chances will increase substantially across the entire area by this
weekend and likely remain high through the start of next week.

.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected today and tonight.

Pendergrast

In the hours before

Special weather statement, Jul 31, 2:06 PM EDT, 9 minutes before
Special Weather Statement
National Weather Service Melbourne FL
206 PM EDT Wed Jul 31 2019

FLZ058-311845-
Okeechobee FL-
206 PM EDT Wed Jul 31 2019

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN OKEECHOBEE COUNTY
UNTIL 245 PM EDT...

At 206 PM EDT, Doppler radar was tracking a strong thunderstorm near
Okeechobee. This storm was drifting toward the northwest at 5
mph.

Winds in excess of 40 mph will be possible with this storm.

Locations impacted include...
Okeechobee, Basinger, Whispering Pines, Basswood Estates and
Okeechobee Airport.

LAT...LON 2717 8088 2716 8089 2717 8091 2719 8091
      2720 8094 2722 8095 2722 8097 2723 8099
      2725 8098 2726 8100 2730 8100 2730 8103
      2732 8103 2741 8102 2732 8077 2721 8080
      2719 8084 2715 8086
TIME...MOT...LOC 1806Z 103DEG 4KT 2726 8088

Glitto
Special weather statement, Jul 31, 2:11 PM EDT, 4 minutes before
Special Weather Statement
National Weather Service Melbourne FL
211 PM EDT Wed Jul 31 2019

FLZ053-311900-
Osceola FL-
211 PM EDT Wed Jul 31 2019

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN OSCEOLA COUNTY UNTIL
300 PM EDT...

At 211 PM EDT, Doppler radar was tracking a strong thunderstorm 7
miles east of Holopaw, moving west at 5 mph.

Winds in excess of 40 mph will be possible with this storm.

Locations impacted include...
Holopaw, Harmony, Forever Florida and Deer Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 2828 8115 2816 8086 2809 8086 2808 8087
      2798 8087 2799 8123
TIME...MOT...LOC 1811Z 107DEG 5KT 2809 8095

Glitto

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 31, 2:06 PM EDTSpecial Weather StatementMLBOkeechobee39 min
Jul 31, 2:11 PM EDTSpecial Weather StatementMLBOsceola49 min
Jul 31, 2:58 PM EDTSpecial Weather StatementMLBSeminole47 min
Jul 31, 3:02 PM EDTSpecial Weather StatementMLBOsceola43 min
Jul 31, 3:35 PM EDTSpecial Weather StatementMLBOrange25 min
Jul 31, 3:44 PM EDTSpecial Weather StatementMLBVolusia46 min
Jul 31, 3:49 PM EDTSpecial Weather StatementMLBSeminole41 min
Jul 31, 4:12 PM EDTSevere Thunderstorm WarningMLBLake33 min
Jul 31, 4:38 PM EDTAreal Flood AdvisoryMLBLake, Volusia112 min
Jul 31, 4:55 PM EDTSpecial Weather StatementMLBLake65 min

Nearby

Severe Thunderstorm Warnings in Florida, 2019Every severe thunderstorm warning in 2019

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; radar from the NEXRAD Level II archive.