Tropical Storm Arthur was forecast by the NHC to continue moving northeastward towards the outer banks of North Carolina while a mid-upper level low over TX moves eastward. This allowed for the wind flow over South FL to be SSW which allowed the Gulf Sea Breeze to form along with the Atlantic Sea Breeze.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS MFL wrote it up.
Tropical Storm Arthur was forecast by the NHC to continue moving northeastward towards the outer banks of North Carolina while a mid-upper level low over TX moves eastward. This allowed for the wind flow over South FL to be SSW which allowed the Gulf Sea Breeze to form along with the Atlantic Sea Breeze. Plenty of residual tropical moisture across the area, along with the eventual sea breeze collision, lead to scattered to numerous strong showers and thunderstorms that eventually pushed eastward towards the east coast metro areas (thanks to the SSW flow). Heavy rain and flooding along with strong wind gusts and small hail were reported. Enhanced helicity/shear in Palm Beach County even led to the development of a funnel cloud.
The local office's own words before the first event, 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 the first event at May 17, 12:14 PM EST, 2 hours 46 minutes earlier.
Area Forecast Discussion National Weather Service Miami FL 114 PM EDT Sun May 17 2020 .Aviation... Mostly VFR conditions are expected today with some shra and tsra development possible across the interior and East Coast this afternoon. Fog/low stratus possible over the interior tonight that could spread into the taf sites again. Another round of afternoon shra and tsra possible tomorrow, with better coverage north of the Miami terminals due to more southerly flow. && .Prev Discussion... /issued 955 AM EDT Sun May 17 2020/ Update... Previous forecast appears to be on track with warm temperatures today and a slight chance of showers and thunderstorms across the interior and East Coast this afternoon. The Atlantic seabreeze should form this afternoon but probably won't make it too far inland given the overall westerly flow. Prev Discussion... /issued 311 AM EDT Sun May 17 2020/ DRIER CONDITIONS EARLY THIS WEEK BEFORE EARLY SUMMER WEATHER PATTERN MIDDLE TO END OF THIS WEEK... Short Term... Today into Tonight... Tropical Storm Arthur is forecast by the NHC to continue to move northeast towards the outer banks of North Carolina, as an mid to upper level low over Texas moves east northeast towards the Tennessee Valley. This will allow for the the wind flow over South Florida to be south southwest bringing in some dry air to the region from the Gulf of Mexico. There could still be some showers and even a thunderstorm over the northeast areas of South Florida this afternoon into early this evening, due to the west coast sea breeze pushing eastward across the region and interacting to with the Lake Okeechobee breeze. The primary impacts from the thunderstorms will be gusty winds, lightning strikes, and locally heavy rainfall. Monday through Tuesday... The mid to upper level low will become stationary over the Tennessee Valley, as a low level trough associated with the low moves eastward from the Gulf of Mexico into South Florida. This will keep the south to southwest wind flow over South Florida allowing for tropical moisture to work into the region ahead of the low level trough. Therefore, POPs will be increasing Monday into Monday and will be in the scattered to likely range on Tuesday with the highs PoPs over the eastern areas each day. Thunderstorms are also possible each afternoon especially over the interior and east coast metro areas where the sea breezes collide. A this time, the primary impacts from the storms will be lightning strikes, gusty winds, and locally heavy rainfall. Long Term... The mid to upper level low will slowly dissipate through end of this week, as the low level trough slowly dissipate over South Florida. This will keep the tropical moisture in place over South Florida, as the winds swing from a south southwest direction middle of the week to more of an easterly direction by late this week. Therefore, scattered to numerous POPs will remain over South Florida for the middle of this week with the highs POPs over the east coast metro areas. The POPs will then decrease to more of a early summer pattern for the end of next week with the highest POPs over the interior and west coast metro areas. Marine... The winds will remain south to southwest direction today into middle of this week, as the wind speeds will be 15 knots or less over all of South Florida waters. The Atlantic seas will be 3 feet or less with the Gulf seas at 2 feet or less through middle of this week. Therefore, boating conditions will be good outside of any showers or thunderstorms. && .Preliminary Point Temps/PoPs... West Palm Beach 73 92 73 88 / 20 40 50 80 Fort Lauderdale 74 91 74 87 / 0 20 40 70 Miami 73 92 73 88 / 0 20 40 60 Naples 75 87 75 85 / 10 20 60 70 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...None. AM...None. GM...None. && Aviation...32/MM
Hazardous Weather Outlook for South Florida National Weather Service Miami FL 1007 AM EDT Sun May 17 2020 AMZ610-630-650-651-670-671-FLZ063-066>075-168-172>174-GMZ656-657-676- 180215- 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- 1007 AM EDT Sun May 17 2020 ...Thunderstorms Possible This Afternoon... This hazardous weather outlook is for South Florida. .DAY ONE...TODAY AND TONIGHT Thunderstorms: A few thunderstorms are possible this afternoon and evening over the interior and East Coast. The primary hazards will be lightning strikes, gusty winds, and locally heavy rainfall. Visibility: Patchy fog is possible over most of South Florida overnight tonight, with patchy smoke over the southern Everglades and interior areas of Collier County due to wildfires. Temperatures: Heat indices could reach 100 degrees over portions of the interior and East Coast this afternoon. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY There will be a chance of thunderstorms across South Florida for the middle to end of THIS week. Gusty winds, locally heavy rainfall, lightning, and waterspouts will be possible with the strongest storms. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time. For more information...visit the National Weather Service in Miami website at www.weather.gov/miami.
Special Weather Statement
National Weather Service Miami FL
303 PM EDT Sun May 17 2020
FLZ071>074-172-173-172015-
Inland Broward County FL-Coastal Broward County FL-
Metro Broward County FL-Metropolitan Miami Dade FL-Inland Miami-
Dade County FL-Coastal Miami Dade County FL-
303 PM EDT Sun May 17 2020
...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN MIAMI-DADE AND SOUTHERN
BROWARD COUNTIES UNTIL 415 PM EDT...
* At 302 PM EDT, National Weather Service meteorologists were
tracking strong thunderstorms along a line extending from near
Pennsuco to Marlins Park. Movement was northeast at 10 mph.
* Small hail, funnel clouds, and winds in excess of 45 mph possible
with these storms.
* Locations impacted include...
Miami, Hialeah, Fort Lauderdale, Pembroke Pines, Hollywood,
Miramar, Davie, Miami Beach, Plantation, Sunrise, Tamarac, Margate,
Coral Gables, Key Biscayne, South Miami, Surfside, Miami Gardens,
Virginia Key, Hallandale and Lauderhill.
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.
Funnel clouds occasionally touch down and produce tornadoes or
waterspouts. Move indoors and stay away from windows.
These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.
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 2592 7993 2585 8004 2573 8006 2565 8028
2592 8049 2623 8020
TIME...MOT...LOC 1902Z 235DEG 9KT 2593 8038 2576 8022
13PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MIAMI FL
356 PM EDT SUN MAY 17 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0348 PM HAIL 1 WSW CORAL WAY VILLAGE 25.72N 80.34W
05/17/2020 E0.50 INCH MIAMI-DADE FL TRAINED SPOTTER
THUNDERSTORM HAIL
&&
EVENT NUMBER MFL2000065
SIThe Miami radar (KAMX), 21 km away, was scanning. The volume nearest the first event began at 19:59 UTC.
6 thunderstorm wind, 1 flood, 1 funnel cloud. Local standard time, as filed.
The public reported a large tree downed onto their roof and fence via social media. Wind gust estimated based off radar at approximately 42 mph (36 kt). Small hail (approximately 0.50 inches, estimated) was also reported with this thunderstorm.
An off-duty NWS Employee reported roadways with several inches of water, some roadways impassable, in Coconut Grove and along Percival Ave and Oak Ave from a thunderstorm and heavy rain that passed through the area.
An off-duty NWS Employee reported multiple large sized tree branches down near the intersection of SW 104th St (Killian Drive) and SW 115th Ave. Wind gust estimated based off radar at approximately 42 mph (36 kt), but were likely higher on the ground. Small hail (approximately 0.50 inches, estimated) was also reported with this thunderstorm.
The public reported multiple softwood trees down in their backyard in the Glenvar Heights/South Miami area via social media. Wind gust estimated based off radar at approximately 42 mph (36 kt), but were likely higher on the ground. Small hail (approximately 0.50 inches, estimated) was also reported with this thunderstorm.
An off-duty NWS Employee reported multiple medium and large sized tree branches down near Percival Ave and Oak Ave. Wind gust estimated based off radar at approximately 42 mph (36 kt), but were likely higher on the ground. Small hail (approximately 0.50 inches, estimated) was also reported with this thunderstorm.
An off-duty NWS Employee reported multiple medium and large sized tree branches down near Hammock Oaks and Old Cutler Rd. Wind gust estimated based off radar at approximately 42 mph (36 kt), but were likely higher on the ground. Small hail (approximately 0.50 inches, estimated) was also reported with this thunderstorm.
An off-duty NWS Employee reported scattered small to medium sized downed tree branches in Parkland, near the Parkland Farmers Market and along the intersection of Parkside Dr and Holmberg Rd. Wind gust estimated based off radar at approximately 40 mph (35 kt), but were likely higher on the ground.
A trained spotter reported a funnel cloud to the SW of the intersection of Big Blue Trace and Wellington Trace from a thunderstorm moving through the area.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Florida in 2020Every state in 2020This day in weather historyWarnings in Florida, May 2020
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 886875, 886879, 886870, 886873, 886866, 886863, 886876, 886883.