Alert archive / Florida / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 34, NWS Miami, FL

May 18, 2020Miami-Dade County, Florida

NWS Miami, FL issued this severe thunderstorm warning at May 18, 2020, 8:10 PM EDT for Miami-Dade County, Florida. It was in force for 27 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
May 18, 2020, 8:10 PM EDT (00:10 UTC)
Expired
May 18, 2020, 8:37 PM EDT
In force
27 min
Issued by
NWS Miami, FL
Area
Storm-based polygon
Tornado
Possible
Hail
0.75 in
Wind
60.0 mph

County Miami-Dade County, FL

The radar

The Miami radar (KAMX), 20 km from the middle of the area, began a volume at 00:09 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
May 18, 8:20 PM EDTTSTM WND DMG1 W Key Biscayne, FLAN OFF DUTY NWS EMPLOYEE REPORTED A LARGE BRANCH BROKE OF A TREE AT THE INTERSECTION OF MASHTA DRIVE AND ALLENDALE ROAD.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched one storm report to this severe thunderstorm warning; the first came 10 minutes after it went out.

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

Miami, FL (KMFL), launched 00:00Z, 0.2 hours before the alert went out and 15 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, Miami, FL at 00:00Z on 2020-05-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1394 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, Miami, FL at 00:00Z on 2020-05-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 163 square meters per square second.193958Sfc1 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
1394 J/kg
Mixed-layer CIN
-19 J/kg
Mixed-layer LCL
628 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
163 m²/s²
0-3 km storm-relative helicity
204 m²/s²
Significant tornado parameter
1.4
Supercell composite
9.6

Open this sounding in Storm Lab

The text

As transmitted.

511 
WUUS52 KMFL 190010
SVRMFL
FLC086-190100-
/O.NEW.KMFL.SV.W.0034.200519T0010Z-200519T0100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Miami FL
810 PM EDT Mon May 18 2020

The National Weather Service in Miami has issued a

* Severe Thunderstorm Warning for...
  Central Miami-Dade County in southeastern Florida...

* Until 900 PM EDT.

* At 810 PM EDT, a severe thunderstorm was located over Coral Gables,
  moving east at 30 mph.

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

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Miami, Miami Beach, Coral Gables, Key Biscayne and South Miami. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

To report severe weather, contact your nearest law enforcement
agency. They will send your report to the National Weather Service
office in Miami. You can also share your report with NWS Miami on
Facebook and Twitter.

&&

LAT...LON 2563 8029 2571 8032 2574 8028 2579 8011
      2565 8015
TIME...MOT...LOC 0010Z 269DEG 27KT 2567 8025 

TORNADO...POSSIBLE
HAIL...0.75IN
WIND...60MPH
 
$$

Cohen
3 follow-up statements
786 
WWUS52 KMFL 190017
SVSMFL

Severe Weather Statement
National Weather Service Miami FL
817 PM EDT Mon May 18 2020

FLC086-190100-
/O.CON.KMFL.SV.W.0034.000000T0000Z-200519T0100Z/
Miami-Dade FL-
817 PM EDT Mon May 18 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 PM EDT
FOR EASTERN MIAMI-DADE COUNTY...

At 816 PM EDT, a severe thunderstorm was approaching Key Biscayne, 
moving east at 25 mph.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect considerable 
         tree damage. Wind damage is also likely to mobile homes, 
         roofs, and outbuildings.

Locations impacted include...
Miami, Miami Beach, Coral Gables, Key Biscayne and South Miami. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Miami. You can also share your report with NWS Miami on Facebook and
Twitter.

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

&&

LAT...LON 2563 8029 2569 8029 2574 8028 2579 8011
      2565 8015
TIME...MOT...LOC 0016Z 251DEG 24KT 2570 8019 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...70MPH
 
$$

Cohen
051 
WWUS52 KMFL 190030
SVSMFL

Severe Weather Statement
National Weather Service Miami FL
830 PM EDT Mon May 18 2020

FLC086-190100-
/O.CON.KMFL.SV.W.0034.000000T0000Z-200519T0100Z/
Miami-Dade FL-
830 PM EDT Mon May 18 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 PM EDT
FOR CENTRAL MIAMI-DADE COUNTY...

At 830 PM EDT, a severe thunderstorm was located over Key Biscayne,
moving east at 15 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Miami, Miami Beach, Key Biscayne, Virginia Key and Fisher Island. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Miami. You can also share your report with NWS Miami on Facebook and
Twitter.

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

&&

LAT...LON 2565 8015 2565 8018 2571 8019 2577 8017
      2579 8011
TIME...MOT...LOC 0030Z 260DEG 14KT 2571 8012 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

Cohen
877 
WWUS52 KMFL 190037
SVSMFL

Severe Weather Statement
National Weather Service Miami FL
837 PM EDT Mon May 18 2020

FLC086-190046-
/O.CAN.KMFL.SV.W.0034.000000T0000Z-200519T0100Z/
Miami-Dade FL-
837 PM EDT Mon May 18 2020

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN MIAMI-DADE COUNTY IS
CANCELLED...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning has been cancelled.  However gusty winds and
heavy rain are still possible with this thunderstorm.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Miami.

LAT...LON 2565 8015 2565 8018 2571 8019 2577 8017
      2579 8011
TIME...MOT...LOC 0036Z 269DEG 27KT 2571 8006 

$$

Cohen

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 Miami, FL wrote its last area forecast discussion before this severe thunderstorm warning went out at May 18, 7:34 PM EDT, 36 minutes earlier.

Area forecast discussion, May 18, 7:34 PM EDT, 36 minutes before
Area Forecast Discussion
National Weather Service Miami FL
734 PM EDT Mon May 18 2020

.Aviation...
A line of showers and thunderstorms will continue to push eastward
over the next several hours. Periods of MVFR and IFR will occur
especially across the east coast terminals as this line moves
through. There will remain a chance of showers through the
overnight across the east coast terminals. Light and variable
winds will increase once again out of the southwest by the middle
of Tuesday morning. Scattered thunderstorms will develop again on
Tuesday afternoon especially interior and east.

&&

.Update...
Updated the forecast based on current radar trends. A line of
thunderstorms will continue to push into the east coast metro
areas over the next hour or two. There could be strong gusty
winds, funnel clouds, and heavy rainfall which could lead to some
flooding of the urban area especially in locations that have
received heavy amounts of rain earlier. Behind this line, showers
will linger for the rest of the evening hours and into the
overnight hours across the eastern and southern areas. Patchy fog
cannot be ruled out across portions of the interior sections late
tonight into early Tuesday morning. Winds on Tuesday will once
again increase out of the southwest as another round of showers
and thunderstorms will develop later Tuesday morning and Tuesday
afternoon. The highest chances will be across the interior and
east coast sections. Some of the thunderstorms could become strong
once again along the east coast and they could contain gusty
winds, heavy rainfall, small hail, and frequent lightning.

&&

.Prev Discussion... /issued 344 PM EDT Mon May 18 2020/

..Strong to severe storms this afternoon/early evening...
..Another round possible overnight in Southwest Florida...

Short Term (Rest of Today and Tonight)...

Tropical Storm Arthur is currently moving over the outer banks of
North Carolina and it will continue to move northeastward off of
the Mid-Atlantic coastline through the rest of the afternoon and
evening hours. At the same time, the tail of Arthur, basically a
trough of low pressure will extend into the southeastern portion
of the country. This also combined with a mid to upper level area
of low pressure moving into the Tennessee Valley and a trough of
low pressure moving into the eastern Gulf of Mexico will allow for
a south southwesterly flow to continue across South Florida. The
Gulf coast sea breeze will be allowed to push inland as the east
coast sea breeze will remain pushed up against the coast. All of
this will result in the development of scattered to numerous
showers and thunderstorms especially over the east coast and the
Lake Okeechobee region. Some of these thunderstorms could be
strong to severe this afternoon and this evening as 500mb temps
will be between -9 and -11C across the region along with steep
lapse rates and high MLCAPE over the area. The primary impacts
with these storms will be heavy rainfall, frequent lightning
strikes, small hail, and gusty winds. The potential for some minor
street flooding is possible as well across the east coast with
the heavy rainfall from thunderstorms.

The trough of low pressure over the eastern Gulf of Mexico will
slowly move across the region and into the Atlantic waters later
this evening and into the overnight hours. This will help to keep
the chances of showers and thunderstorms around during this time
frame. The greatest chances of showers and thunderstorms will
continue to be across the east coast as well as the Lake Okeechobee
region.

Long Term (Tuesday through Sunday)...

The mid-level trough will push into the Gulf waters late tonight
into early Tuesday morning likely spurring additional convection.
Portions of Southwest Florida could see vigorous showers and
thunderstorms overnight spurred by the mid and upper level support
provided by the trough moving through with activity pushing
eastward through the morning. The afternoon focus will remain
along the east coast where the sea breeze, the surface boundary,
and remnant moisture could interact to produce some convection.

The mid-level low will emerge over the Tennessee River Valley late
Tuesday into Wednesday. The surface boundary and associated moisture
should slip to the southeast of the area which may allow a brief dry
slot for portions of the area to emerge. Any dryness should be short-
lived as the mid-level low pulls back northward with the moisture
returning in time for the sea breeze convection to potentially
produce thunderstorms with the potential for heavy rain.

The generally unsettled pattern will persist as the rich moisture
remains across the region through the rest of the week. Diurnal
heating and the presence of sea breezes due to a light synoptic flow
should allow mentionable thunderstorm chances most days except for
those brief winds where a dry slot of air could move through
portions of the region. A ridge of high pressure may try to build
over the aloft over the Gulf but it may not be able to cap
convection as much as a stronger high centered closer to the area.
Temperatures will remain warm with upper 80s and 90s on most
afternoons and mid 60s to 70s for minimum temperatures.

Marine...
Southwesterly flow will continue through the middle of the
week across the Atlantic and Gulf coastal waters. Seas will
generally remain at 3 feet or less across the local waters.
Scattered to numerous showers and thunderstorms will be possible
each day through the end of the week. Winds and waves will be higher
in and around any showers or thunderstorms.

Prev Discussion... /issued 135 PM EDT Mon May 18 2020/

Aviation...
Mainly VFR conditions will prevail throughout the forecast period.
The exception to this will be in and around any showers or
thunderstorms that develop this afternoon and this evening where
periods of MVFR or even IFR conditions are possible. South to
southwesterly winds will continue through this evening between 10
and 15 knots. Patchy fog development is possible across the
interior sections during the overnight hours.

Prev Discussion... /issued 1121 AM EDT Mon May 18 2020/

Update / Mesoscale Discussion...

Midlevel water vapor loops indicate a well-defined southern-stream
cyclonic-flow perturbation centered over the Middle Gulf waters well
off the Tampa Bay Area coast.  This feature will continue drifting
eastward or even southeastward, as the centroid of its accompanying
cyclonically-curved jet streak still lies upstream of the trough
axis.  As a result, CVA-associated height falls and related DCVA-
enhanced midlevel cooling preceding this shortwave trough will
continue to overspread the NWS Miami County Warning Area through the
day -- with 500-mb temperatures falling to -8C to -10C from
southeast to northwest.

Meanwhile the low-level mass response preceding the wave is favoring
enhanced isentropic ascent and regenerative convection within a
corridor from the east-central Gulf toward areas from Tampa to Fort
Myers.  This activity will progress northeastward to eastward, with
diurnally destabilizing inflow favoring an increasing potential for
robust convection to accompany this activity across Glades and
Hendry Counties toward/across the Lake Okeechobee region from late
morning into early afternoon.  Meanwhile, areas of cloud-thinning
and partial clearing southeastward of this regime toward southeast
Florida will favor strong destabilization by this afternoon.
Concurrently, differential-heating-induced baroclinicity and
solenoidal circulations along the edges of thicker/denser mid/high-
level cloud decks and old outflow accompanying the more pronounced
isentropic-ascent regime, coupled with decaying outflow from
dissipating convection presently ongoing over Biscayne Bay vicinity,
along with some potential for a modest/broad east-coast sea-breeze
circulation to ensue, will favor a marked uptick in robust
convective potential this afternoon across southeast Florida.
Convection will preferentially regenerate into areas of highest
theta-e through the afternoon into the early evening -- i.e.,
southeastward to southward.

Given the extremely moist planetary boundary layer -- associated
with lowest-100-mb mean mixing ratios of 15-16 g/kg -- convective
inhibition will be low amid sufficient low-level ascent -- aided by
the larger-scale synoptic ascent -- to support high confidence in
the aforementioned regenerative convective regime taking place
today.  Moreover, it appears that an elevated mixed layer has
overspread South Florida from the Sierra Madre Mountains of Mexico --
 accompanied by maximum midlevel lapse rates of 7.0-7.5 C/km.
Related enhanced midlevel CAPE density will favor intense parcel
accelerations, offsetting the effects of precipitation loading / dry
entrainment, in support of robust updrafts.  While modest, the
presence of 20-30 kt of effective shear -- accompanying the enhanced
midlevel height gradient peripheral to the shortwave trough -- will
combine with 2000-3000 J/kg of midlevel-instability-enhanced
boundary-layer buoyancy for intense multicell clusters. In addition
to sporadic instances of small hail, these parameters suggest large
hail -- to around quarter size -- may occur especially where
updrafts remain in more separated/discrete phases.  Moreover, the
enhanced downward buoyancy accompanying the EML could favor damaging
wind gusts where more substantial cell interactions take place among
the multicell clusters.  Confidence continues to grow in isolated
severe winds and hail affecting southeast Florida this afternoon --
especially from Downtown Miami / Miami Beach area northward through
coastal/metro Palm Beach County.  The most-likely timing is 1-7PM.
The latest output from the Statistical Severe Risk Assessment
Model (SSCRAM) depicts both conditional and unconditional
probabilities for damaging wind gusts and severe hail across these
coastal and metro areas of South Florida this afternoon, further
increasing confidence in these convective hazards materializing in
the strongest storms that develop. However, earlier scattered
strong thunderstorms may also affect Hendry/Glades Counties
through the Lake Okeechobee region.

In addition to severe hail/wind potential today, there is also a
reasonable-worst case scenario for a slight inland mass flux in the
lowest 1 km AGL to favor effective SRH near 100 m2/s2 in immediate
proximity to the east coast.  Related streamwise-vorticity
enhancements could conditionally favor the potential for convection
to briefly attain supercellular characteristics within 10-15 miles
of the immediate Atlantic coast -- locally boosting the hail/wind
potential, and possibly supporting a brief/weak tornado.  The
enhanced midlevel lapse rates and related parcel accelerations would
also contribute to enhanced vorticity stretching in the low-levels,
and thus there is a reasonable worst-case scenario for brief tornado
with the east-coast-area convective regime.

Finally, given widespread 1.9-2.0-inch precipitable water, enhanced
outflow establishing foci for convective regeneration/training amid
low MLCINH, and anticipated slow multicellular-convection motion,
heavy rain and flooding will be a concern -- especially for the east-
coast metro areas and vicinity.  If training convection were to
become established over areas that experienced several inches of
rain over the past few days, the potential for significant urban
flooding could occur this afternoon.  Such potential would be highly
localized, though antecedent conditions may bolster this risk.

Ultimately, there remains some uncertainty regarding the exact
details of most-likely strong/severe risk, along with a bit of
uncertainty about the maximum magnitude of potential convective
intensity. This is especially the case given the modest large-scale
ascent over the region. However, there is growing confidence in a
severe-thunderstorm and flooding potential for the east coast metro
areas and vicinity, and all interests across South Florida are
encouraged to monitor weather conditions closely today.
&&

.Preliminary Point Temps/PoPs...
West Palm Beach  72  87  72  87 /  50  60  20  60
Fort Lauderdale  75  87  74  86 /  50  60  20  60
Miami            74  88  74  87 /  50  60  20  50
Naples           72  85  73  86 /  60  50  10  20

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
GM...None.
&&

Update...55/CWC
Aviation...55/CWC
Hazardous weather outlook, May 18, 4:21 PM EDT, 3 hours 49 minutes before
Hazardous Weather Outlook for South Florida
National Weather Service Miami FL
421 PM EDT Mon May 18 2020

AMZ610-630-650-651-670-671-FLZ063-066>075-168-172>174-GMZ656-657-676-
190830-
Lake Okeechobee-Biscayne Bay-
Coastal waters from Jupiter Inlet to Deerfield Beach FL out 20 NM-
Coastal waters from Deerfield Beach to Ocean Reef FL out 20 NM-
Waters from Jupiter Inlet to Deerfield Beach FL from 20 to 60 NM-
Waters from Deerfield Beach to Ocean Reef FL from 20 to 60 NM
excluding the territorial waters of Bahamas-Glades-Hendry-
Inland Palm Beach-Metro Palm Beach-Coastal Collier-Inland Collier-
Inland Broward-Metro Broward-Inland Miami-Dade-Metro Miami-Dade-
Mainland Monroe-Coastal Palm Beach-Coastal Broward-Coastal Miami-
Dade-Far South Miami-Dade-
Coastal waters from Chokoloskee to Bonita Beach FL out 20 NM-
Coastal waters from East Cape Sable to Chokoloskee FL out 20 NM-
Waters from Chokoloskee to Bonita Beach FL from 20 to 60 NM-
421 PM EDT Mon May 18 2020

...STRONG TO POSSIBLE SEVERE STORMS THIS EVENING...
...HEAVY RAINFALL AND LOCALIZED FLOODING POSSIBLE THIS EVENING...

This hazardous weather outlook is for South Florida.

.DAY ONE...TONIGHT

Thunderstorms: Scattered to numerous thunderstorms are possible
across all of South Florida and its waters this evening. A few of the
thunderstorms could become strong, to even severe, with gusty winds,
hail, frequent lightning strikes, and heavy rainfall. A weak
isolated tornado is possible across eastern portions of South
Florida.

Tornado: A weak isolated tornado may be possible this evening with
the strong to severe storms, primarily across the east coast of South
Florida.

Wind: The strongest thunderstorms could produce wind gusts up to 60
mph.

Hail: The strongest thunderstorms could produce hail up to quarter
size.

Flooding: Heavy rainfall from thunderstorms, and repeated rounds of
showers/storms, can produce flooding in low lying and poorly
drainage areas, especially for the east coast where it has been
raining the past few days.

Waterspouts: There is a slight chance of waterspouts with any
thunderstorms and showers that do develop over the local waters.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

There will be a chance of thunderstorms across South Florida
throughout the week. Gusty winds, locally heavy rainfall, lightning,
and waterspouts will be possible with the strongest storms.

The threat of rip currents for Atlantic beaches will also increase
towards the end of the work week as winds become more easterly over
South Florida.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please relay any information about
observed severe weather to the NWS while following all local, state,
and CDC guidelines.

For more information...visit the National Weather Service in
Miami website at www.weather.gov/miami.

In the hours before

Special weather statement, May 18, 7:12 PM EDT, 58 minutes before
Special Weather Statement
National Weather Service Miami FL
712 PM EDT Mon May 18 2020

FLZ073-074-173-174-190015-
Metropolitan Miami Dade FL-Far South Miami-Dade County FL-
Inland Miami-Dade County FL-Coastal Miami Dade County FL-
712 PM EDT Mon May 18 2020

...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL MIAMI-DADE COUNTY UNTIL
815 PM EDT...

* At 712 PM EDT, National Weather Service meteorologists were
  tracking strong thunderstorms along a line extending from 7 miles
  northeast of Fortymile Bend to near Shark Valley Obs Tower to
  Pa-Hay-Okee Overlook. Movement was east at 30 mph.

* Wind gusts up to 50 mph possible with these storms.

* Locations impacted include...
  Miami, Hialeah, Homestead, Coral Gables, South Miami, Homestead
  General Airport, The Redland, Kendall, Homestead Miami Speedway,
  Doral, Hialeah Gardens, Pinecrest, Miami Springs, Sweetwater,
  Florida City, West Miami, Medley, Westchester, Naranja and Glenvar
  Heights.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

This activity was also developing in an environment favorable for the
formation of funnel clouds. Stay tuned to NOAA weather radio and
local media for additional updates and possible warnings.

To report severe weather, contact your nearest law enforcement
agency. You can also share your report with NWS Miami on Facebook and
Twitter.

&&

LAT...LON 2587 8028 2574 8027 2539 8044 2540 8075
      2555 8064 2585 8064
TIME...MOT...LOC 2312Z 267DEG 25KT 2584 8075 2560 8070 2542 8081

Cohen/13
Local storm report, May 18, 7:14 PM EDT, 56 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MIAMI FL
714 PM EDT MON MAY 18 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0537 PM     TSTM WND GST     3 SSE NAPLES            26.10N  81.78W
05/18/2020  M58 MPH          COLLIER            FL   MESONET

            A WIND GUST OF 58 MPH WAS MEASURED AT THE EARTH
            NETWORKS SITE NPLHH AT THE HAMILTON HARBOR YACHT CLUB IN
            NAPLES.

0546 PM     TSTM WND GST     2 WNW EAST NAPLES       26.15N  81.77W
05/18/2020  M51 MPH          COLLIER            FL   ASOS

            A WIND GUST OF 51 MPH WAS MEASURED AT THE ASOS AT
            KAPF/NAPLES MUNICIPAL AIRPORT.

0547 PM     MARINE TSTM WIND 1 S MARCO ISLAND        25.92N  81.73W
05/18/2020  M39 MPH          COLLIER            FL   MESONET

            A WIND GUST OF 39 MPH/34 KNOTS WAS MEASURED AT THE
            EARTH NETWORK SITE AT THE CHARTER CLUB OF MARCO ISLAND.

0549 PM     MARINE TSTM WIND 3 N MARCO ISLAND        25.98N  81.73W
05/18/2020  M43 MPH          COLLIER            FL   MESONET

            A WIND GUST OF 43 MPH/37 KNOTS WAS MEASURED AT THE
            EARTH NETWORK SITE IN ISLE OF CAPRI.

0554 PM     MARINE TSTM WIND 1 SW NAPLES             26.13N  81.81W
05/18/2020  M47 MPH          GMZ656             FL   OTHER FEDERAL

            A WIND GUST OF 47 MPH/41 KNOTS FROM THE NW WAS MEASURED
            AT THE NOS STATION AT NAPLES PIER.

0614 PM     MARINE TSTM WIND EVERGLADES CITY         25.86N  81.39W
05/18/2020  M45 MPH          COLLIER            FL   MESONET

            A WIND GUST OF 45 MPH/39 KNOTS WAS MEASURED AT THE
            EARTH NETWORKS SITE AT THE EVERGLADES CITY SCHOOL.

0620 PM     FLOOD            3 SSE PELICAN BAY       26.19N  81.80W
05/18/2020                   COLLIER            FL   SOCIAL MEDIA

            PICTURE OF STREET FLOODING WAS RECEIVED VIA TWITTER AT
            THE INTERSECTION OF TAMIAMI TRAIL AND OHIO DRIVE.

&&

EVENT NUMBER MFL2000081
EVENT NUMBER MFL2000082
EVENT NUMBER MFL2000083
EVENT NUMBER MFL2000084
EVENT NUMBER MFL2000085
EVENT NUMBER MFL2000086
EVENT NUMBER MFL2000087

MOLLEDA
Special weather statement, May 18, 7:17 PM EDT, 53 minutes before
Special Weather Statement
National Weather Service Miami FL
717 PM EDT Mon May 18 2020

FLZ067-071-190000-
Inland Broward County FL-Inland Palm Beach County FL-
717 PM EDT Mon May 18 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN BROWARD AND SOUTHWESTERN
PALM BEACH COUNTIES UNTIL 800 PM EDT...

* At 716 PM EDT, National Weather Service meteorologists were
  tracking strong thunderstorms along a line extending from near Big
  Cypress Seminole Reservation to 6 miles north of Miccosukee Service
  Plaza to 7 miles west of Intersection Alligator Alley And Miami
  Canal. Movement was northeast at 40 mph.

* Winds in excess of 45 mph and funnel clouds possible with these
  storms.

* Locations impacted include...
  Mile Marker 30 On Alligator Alley, Holey Land Wildlife Refuge,
  Intersection Alligator Alley And Miami Canal and Rotenberger
  Wildlife Refuge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These winds can down small tree limbs and branches, and blow around
unsecured small objects. Seek shelter in a safe building until the
storm passes.

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

This activity was also developing in an environment favorable for the
formation of funnel clouds. Stay tuned to NOAA weather radio and
local media for additional updates and possible warnings.

To report severe weather, contact your nearest law enforcement
agency. You can also share your report with NWS Miami on Facebook and
Twitter.

&&

LAT...LON 2620 8032 2612 8062 2632 8073 2633 8088
      2642 8088 2658 8065 2644 8041
TIME...MOT...LOC 2316Z 233DEG 36KT 2637 8093 2626 8082 2612 8074

Cohen/13
Special weather statement, May 18, 7:27 PM EDT, 43 minutes before
Special Weather Statement
National Weather Service Miami FL
727 PM EDT Mon May 18 2020

FLZ071-072-190000-
Inland Broward County FL-Metro Broward County FL-
727 PM EDT Mon May 18 2020

...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL BROWARD COUNTY UNTIL 800
PM EDT...

* At 727 PM EDT, National Weather Service meteorologists were
  tracking a strong thunderstorm near Intersection Alligator Alley
  And Miami Canal, or 16 miles west of Pembroke Pines, moving east at
  40 mph.

* Winds in excess of 45 mph possible with this storm.

* Locations impacted include...
  Davie, Sunrise, Weston, Mile Marker 30 On Alligator Alley, East
  Toll Gate On Alligator Alley, Intersection I-75 And U.S. 27 and
  Markham 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.

This activity was also developing in an environment favorable for the
formation of funnel clouds. Stay tuned to NOAA weather radio and
local media for additional updates and possible warnings.

To report severe weather, contact your nearest law enforcement
agency. You can also share your report with NWS Miami on Facebook and
Twitter.

&&

LAT...LON 2603 8062 2610 8062 2613 8063 2621 8032
      2608 8033
TIME...MOT...LOC 2327Z 253DEG 37KT 2609 8059

Cohen
Special weather statement, May 18, 7:46 PM EDT, 24 minutes before
Special Weather Statement
National Weather Service Miami FL
746 PM EDT Mon May 18 2020

FLZ072>074-172>174-190030-
Coastal Broward County FL-Metro Broward County FL-
Metropolitan Miami Dade FL-Far South Miami-Dade County FL-
Inland Miami-Dade County FL-Coastal Miami Dade County FL-
746 PM EDT Mon May 18 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN MIAMI-DADE AND SOUTHERN
BROWARD COUNTIES UNTIL 830 PM EDT...

* At 746 PM EDT, National Weather Service meteorologists were
  tracking strong thunderstorms along a line extending from near
  Miramar to near Florida City. Movement was east at 35 mph.

* Winds in excess of 45 mph possible with these storms.

* Locations impacted include...
  Miami, Hialeah, Pembroke Pines, Hollywood, Miramar, Miami Beach,
  Homestead, Coral Gables, Key Biscayne, South Miami, Surfside,
  Hallandale, Homestead Miami Speedway, Black Point, Miami Gardens,
  Turkey Point, Virginia Key, Kendall, North Miami, and Doral.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These winds can down small tree limbs and branches, and blow around
unsecured small objects. Seek shelter in a safe building until the
storm passes.

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

To report severe weather, contact your nearest law enforcement
agency. You can also share your report with NWS Miami on Facebook and
Twitter.

&&

LAT...LON 2602 8005 2538 8017 2539 8046 2573 8032
      2589 8040 2599 8036
TIME...MOT...LOC 2346Z 267DEG 29KT 2599 8039 2541 8049

Cohen
Special weather statement, May 18, 7:48 PM EDT, 22 minutes before
Special Weather Statement
National Weather Service Miami FL
748 PM EDT Mon May 18 2020

FLZ067-190045-
Inland Palm Beach County FL-
748 PM EDT Mon May 18 2020

...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL PALM BEACH COUNTY UNTIL
845 PM EDT...

* At 748 PM EDT, National Weather Service meteorologists were
  tracking strong thunderstorms along a line extending from near
  Okeelanta to 12 miles east of Holey Land Wildlife Refuge to near
  Intersection I-75 And U.S. 27. Movement was northeast at 40 mph.

* Wind gusts up to 50 mph possible with these storms.

* Locations impacted include...
  Wellington, Royal Palm Beach, Parkland, Loxahatchee NWR,
  Loxahatchee Groves, Lion Country Safari Park, The Acreage and
  Mission Bay.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These winds can down small tree limbs and branches, and blow around
unsecured small objects. Seek shelter in a safe building until the
storm passes.

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

This activity was also developing in an environment favorable for the
formation of funnel clouds. Stay tuned to NOAA weather radio and
local media for additional updates and possible warnings.

To report severe weather, contact your nearest law enforcement
agency. You can also share your report with NWS Miami on Facebook and
Twitter.

&&

LAT...LON 2633 8041 2643 8044 2658 8068 2680 8049
      2677 8023 2633 8022
TIME...MOT...LOC 2348Z 223DEG 36KT 2653 8067 2648 8053 2622 8040

Cohen

The office that day

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

IssuedProductOfficeCountiesLasted
May 18, 8:29 PM EDTSpecial Marine WarningMFL2 hr
May 18, 10:51 PM EDTSpecial Marine WarningMFL54 min
May 18, 11:43 PM EDTSpecial Marine WarningMFL47 min
May 19, 3:54 AM EDTSpecial Marine WarningMFL66 min
May 19, 4:56 AM EDTSpecial Marine WarningMFL64 min
May 19, 5:55 AM EDTSpecial Marine WarningMFL65 min
May 19, 10:59 AM EDTSpecial Weather StatementMFLMiami-Dade46 min
May 19, 12:10 PM EDTSpecial Weather StatementMFLMonroe80 min
May 19, 12:16 PM EDTSpecial Marine WarningMFL44 min
May 19, 12:44 PM EDTSpecial Marine WarningMFL46 min
May 19, 1:03 PM EDTSpecial Marine WarningMFL57 min
May 19, 1:13 PM EDTSpecial Weather StatementMFLMiami-Dade47 min
May 19, 1:24 PM EDTSpecial Weather StatementMFLCollier51 min
May 19, 1:26 PM EDTSpecial Marine WarningMFL34 min
May 19, 1:30 PM EDTSpecial Weather StatementMFLMiami-Dade30 min
May 19, 1:39 PM EDTSpecial Weather StatementMFLMiami-Dade36 min
May 19, 1:59 PM EDTSpecial Weather StatementMFLMiami-Dade46 min
May 19, 2:00 PM EDTSpecial Weather StatementMFLPalm Beach45 min
May 19, 2:01 PM EDTSpecial Weather StatementMFLMiami-Dade44 min
May 19, 2:04 PM EDTSpecial Marine WarningMFL86 min
May 19, 2:20 PM EDTSpecial Weather StatementMFLPalm Beach55 min
May 19, 2:28 PM EDTSpecial Weather StatementMFLBroward47 min
May 19, 2:29 PM EDTSpecial Marine WarningMFL46 min
May 19, 2:30 PM EDTSpecial Weather StatementMFLBroward45 min
May 19, 2:32 PM EDTSpecial Marine WarningMFL58 min
May 19, 2:49 PM EDTSpecial Weather StatementMFLPalm Beach56 min
May 19, 3:30 PM EDTSpecial Marine WarningMFL60 min
May 19, 4:23 PM EDTSpecial Weather StatementMFLPalm Beach52 min
May 19, 4:35 PM EDTSpecial Marine WarningMFL40 min
May 19, 4:39 PM EDTSpecial Marine WarningMFL66 min
May 19, 5:08 PM EDTSpecial Marine WarningMFL67 min
May 19, 5:18 PM EDTSpecial Marine WarningMFL57 min
May 19, 5:57 PM EDTSpecial Marine WarningMFL63 min
May 19, 6:01 PM EDTSpecial Marine WarningMFL59 min
May 19, 7:02 PM EDTSpecial Marine WarningMFL43 min

Nearby

Severe Thunderstorm Warnings in Florida, 2020Every severe thunderstorm warning in 2020

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.