Sea breeze storms developed over a moist and unstable airmass. Some storms produced damaging lightning strikes.
Every event with a place to put it. Tap one for its entry below.
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 JAX wrote it up.
Sea breeze storms developed over a moist and unstable airmass. Some storms produced damaging lightning strikes.
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 Jacksonville, FL wrote its last area forecast discussion before the first event at Aug 12, 8:50 AM EST, 3 hours 14 minutes earlier.
Area Forecast Discussion National Weather Service Jacksonville FL 950 AM EDT Sun Aug 12 2018 .UPDATE... Mostly sunny to partly cloudy to start the day with just a few showers that were offshore but dissipating recently. Mean 1000-700 mb flow continues to be west-southeast but not as strong as prior days now is about 8 kts. This should allow the east coast seabreeze to push inland further today to west of I-95 this aftn. Morning sounding parameters showed an overall better potential for convection than the prior 2 days with a weaker CAP and better moisture profile. PWAT was 1.93 inches but drier air with PWATS down to about 1.5 inches is pushing in across southeast GA at this time per GOES imagery and RAP guidance. Modified sounding yielded SBCAPE of about 3000-3500 J/kg and strong downdraft CAPE of about 1100 J/kg. Guidance has also trended higher for POPs than past 2 days but still think its below climate average for most of the region. This seems reasonable since temps aloft continue to be warmer than normal at -6.5 at 500 mb. Have adjusted POPs slightly down to account for current trends and hi-res guidance. Highs again in the lower 90s with heat indices about 100- 105. && .AVIATION... VFR prevails outside of convection. Scattered showers and storms are forecast to develop with the best chances around the 19z-23z time frame but lowest chances expected around SSI. Light west southwest flow expected with east coast sea breeze pushing through SSI, CRG, SGJ, and JAX terminals around the 16z-22z time frame...with earliest wind shifts occurring at SSI and SGJ. && .MARINE... Offshore flow will turn to the southeast and south this afternoon around 10-15 kt. Seas around 1-3 ft today with mix of wind waves and east swells. Rip Currents: Mainly low Risk through Monday due to weak low surf conditions. && .PRELIMINARY POINT TEMPS/POPS... AMG 92 74 91 73 / 20 20 30 30 SSI 91 76 89 76 / 30 30 40 30 JAX 93 75 92 74 / 40 30 40 30 SGJ 90 74 90 74 / 50 40 50 30 GNV 91 74 89 74 / 50 30 50 20 OCF 90 74 89 73 / 60 30 50 30 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AM...None. && Shashy/Bricker
Special Weather Statement
National Weather Service Jacksonville FL
104 PM EDT SUN AUG 12 2018
FLZ033-038-133-138-121730-
Coastal Flagler FL-Coastal St. Johns FL-Inland Flagler FL-
Inland St. Johns FL-
104 PM EDT SUN AUG 12 2018
...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN FLAGLER AND
SOUTHEASTERN ST. JOHNS COUNTIES UNTIL 130 PM EDT...
At 103 PM EDT, Doppler radar was tracking a thunderstorm over
Marineland, or near Palm Coast, moving east at 5 mph.
Wind gusts of 40 mph can be expected along with possible minor wind
damage. Frequent lightning and localized flooding possible.
Locations impacted include...
Palm Coast, Marineland and Crescent Beach.
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.
Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
&&
LAT...LON 2953 8111 2956 8129 2969 8132 2976 8118
2954 8110
TIME...MOT...LOC 1703Z 258DEG 4KT 2963 8124
SHASHYThe Jacksonville radar (KJAX), 114 km away, was scanning. The volume nearest the first event began at 17:03 UTC.
2 lightning. Local standard time, as filed.
A fire was caused by a lightning strike on Palm Lakes Parkway in Palm Coast. The cost of damage was unknown, but it was estimated for inclusion of the event in Storm Data.
A tree was struck by lightning along Sanchez Road. The cost of damage was estimated for inclusion of the event in Storm Data. The time of damage was based on lightning data.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Florida in 2018Every state in 2018This day in weather historyWarnings in Florida, August 2018
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: 781632, 781633.