A late season cold front was over SE GA under a mid level low. This feature combined with daytime heating and high moisture spawned a line of strong to severe storms over NE Florida that neared the Atlantic coast of Duval county during the early afternoon.
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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 JAX wrote it up.
A late season cold front was over SE GA under a mid level low. This feature combined with daytime heating and high moisture spawned a line of strong to severe storms over NE Florida that neared the Atlantic coast of Duval county during the early afternoon. A weak and brief tornado touched down near Mayport.
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 Jul 27, 7:17 AM EST, 5 hours 15 minutes earlier.
Area Forecast Discussion National Weather Service Jacksonville FL 817 AM EDT Thu Jul 27 2017 .UPDATE... A mid level low will remain nearly stationary over SE GA Today, with a weak surface low under it. With diurnal heating, convective coverage will increase later this morning into the afternoon. With the low stationary, slow storm movement is expected, therefore an increased chance for heavy rainfall and potential flooding. Temperatures over SE GA and far Northern Florida will be slightly below normal Today due to the precipitation and cloud coverage. && .AVIATION... Low stratus and visibilities will rise this morning. Convection will increase in coverage through the day with gusty storms and heavy rainfall expected. && .PRELIMINARY POINT TEMPS/POPS... AMG 89 74 94 76 / 60 20 30 10 SSI 86 78 90 79 / 70 40 30 10 JAX 89 74 94 77 / 80 50 40 10 SGJ 89 78 92 76 / 60 30 20 10 GNV 91 73 92 75 / 60 20 20 10 OCF 92 74 92 75 / 30 20 20 10 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AM...None. && Struble
Hazardous Weather Outlook National Weather Service Jacksonville FL 550 AM EDT Thu Jul 27 2017 AMZ450-452-454-470-472-474-FLZ020>025-030>033-035>038-040-124-125- GAZ132>136-149>154-162>166-281000- Coastal waters from Altamaha Sound to Fernandina Beach FL out 20 NM- Coastal waters from Fernandina Beach to St. Augustine FL out 20 NM- Coastal waters from St. Augustine to Flagler Beach FL out 20 NM- Waters from Altamaha Sound GA to Fernandina Beach FL from 20 to 60 NM- Waters from Fernandina Beach to St. Augustine FL from 20 to 60 NM- Waters from St. Augustine to Flagler Beach FL from 20 to 60 NM- Hamilton-Suwannee-Columbia-Baker-Inland Nassau-Inland Duval-Union- Bradford-Clay-St. Johns-Gilchrist-Alachua-Putnam-Flagler-Marion- Coastal Nassau-Coastal Duval-Coffee-Jeff Davis-Bacon-Appling- Wayne-Atkinson-Ware-Pierce-Brantley-Inland Glynn-Coastal Glynn- Echols-Clinch-Charlton-Inland Camden-Coastal Camden- 550 AM EDT Thu Jul 27 2017 ...LOCALIZED FLOODING POSSIBLE THIS AFTERNOON AND EARLY EVENING ALONG THE INTERSTATE 95 CORRIDOR... This Hazardous Weather Outlook is for Northeast Florida, Southeast Georgia and the Adjacent Coastal Waters. .DAY ONE...Today and Tonight... Patchy fog will be possible across portions of inland northeast Florida and southeast Georgia early this morning. Numerous thunderstorms are expected to develop by late this morning and early afternoon over coastal southeast Georgia and across much of northeast Florida. Activity will increase in coverage and will move slowly southward this afternoon. Slow moving downpours over saturated ground conditions will result in a risk of localized and urban flooding this afternoon and evening, particularly along the Interstate 95 corridor. Frequent lightning strikes are possible within stronger activity. A few strong wind gusts will be possible late this afternoon over north central Florida and coastal northeast Florida, generally from St. Augustine southward. Thunderstorms may linger through early evening all along the Interstate 95 corridor. .DAYS TWO THROUGH SEVEN...Friday through Wednesday... Scattered thunderstorms are expected to develop throughout southeast Georgia and along the Interstate 10 corridor on Friday afternoon, with strong to severe thunderstorms possible over southeast Georgia during the late afternoon and evening hours. Damaging wind gusts and frequent lightning strikes will be the primary hazards. A cold front will approach southeast Georgia from the north on Saturday, with numerous thunderstorms expected to develop during the afternoon hours. Strong to severe thunderstorms are possible, with activity moving into northeast Florida during the evening and overnight hours. This front will stall over northeast Florida by late Sunday and through early next week, with numerous thunderstorms expected each day for all of north central Florida and most of northeast Florida. Flooding is expected to become a primary hazard early next week as several rounds of strong thunderstorms potentially impact north central and northeast Florida. The frontal boundary will begin to move slowly northward towards midweek, with numerous thunderstorms expected to expand into coastal southeast Georgia by Wednesday, with scattered thunderstorms forecast for inland southeast Georgia. .SPOTTER INFORMATION STATEMENT... Spotters are asked to report rainfall amounts in excess of 2 inches, in addition to significant street flooding or flood waters entering homes and/or businesses this afternoon. For additional information, visit the National Weather Service in Jacksonville website on the internet at weather.gov/jax. Nelson
Special Weather Statement
National Weather Service Jacksonville FL
1243 PM EDT THU JUL 27 2017
FLZ025-032-125-271730-
Inland Duval FL-Clay FL-Coastal Duval FL-
1243 PM EDT THU JUL 27 2017
...SIGNIFICANT WEATHER ADVISORY FOR NORTH CENTRAL CLAY AND
SOUTHEASTERN DUVAL COUNTIES UNTIL 130 PM EDT...
At 1243 PM EDT, Doppler radar was tracking a strong thunderstorm over
Lakeside, or near Orange Park, moving northeast at 20 mph.
Wind gusts of 40 mph can be expected along with possible minor wind
damage.
Locations impacted include...
Jacksonville, Orange Park, Unf, Mandarin, Arlington, Fleming Island,
Baymeadows, Ortega, Craig Field and Oakleaf Plantation.
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 3012 8167 3012 8168 3011 8168 3004 8179
3016 8201 3048 8166 3028 8143
TIME...MOT...LOC 1643Z 233DEG 19KT 3016 8179
HESSSpecial Weather Statement
National Weather Service Jacksonville FL
114 PM EDT THU JUL 27 2017
FLZ032-037-271800-
Putnam FL-Clay FL-
114 PM EDT THU JUL 27 2017
...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN PUTNAM AND
SOUTHWESTERN CLAY COUNTIES UNTIL 200 PM EDT...
At 114 PM EDT, Doppler radar was tracking a strong thunderstorm over
Melrose, moving east at 10 mph.
Wind gusts of 40 to 45 mph can be expected along with possible minor
wind damage.
Locations impacted include...
Interlachen, Keystone Heights, Melrose, Melrose Landing, George's
Lake, Hollister, Lake Geneva, Florahome, Putnam Hall and Carraway.
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 2956 8180 2961 8206 2967 8206 2970 8205
2980 8205 2986 8177
TIME...MOT...LOC 1714Z 278DEG 7KT 2970 8201
HESSSpecial Weather Statement National Weather Service Jacksonville FL 124 PM EDT THU JUL 27 2017 FLZ030-031-036-271815- Union FL-Alachua FL-Bradford FL- 124 PM EDT THU JUL 27 2017 ...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN ALACHUA...CENTRAL BRADFORD AND SOUTH CENTRAL UNION COUNTIES UNTIL 215 PM EDT... At 124 PM EDT, Doppler radar was tracking a strong thunderstorm near Alachua, or 7 miles south of Worthington Spring, moving northeast at 15 mph. Wind gusts of 40 to 45 mph can be expected along with possible minor wind damage. Locations impacted include... Worthington Spring, Alachua, Worthington Springs, New River, Beasley, Sampson, Waldo, La Crosse and Brooker. 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 2970 8243 2983 8257 3002 8230 2982 8211 TIME...MOT...LOC 1724Z 226DEG 12KT 2982 8244 HESS
The Jacksonville radar (KJAX), 30 km away, was scanning. The volume nearest the first event began at 17:33 UTC.
2 thunderstorm wind, 1 tornado. Local standard time, as filed.
A tree was blown down onto a homne along Wonderwood Drive. The cost of damage was estimated so the event could be included in Storm Data.
Thunderstorms damaged a gold course just south of Mayport. A tractor trailer was toppled in addition to roof damage and damage occurred to cars from construction debris. The time of the damage was based on radar. The cost of damage was unknown, but it was estimated so the event could be included in Storm Data.
A line of strong thunderstorms approached Mayport and straight line winds produced minor damage. This damage preceded a tornado over the mouth of the St. Johns River that touched down briefly as an EF0 tornado on Huguenot Beach Park. A lifeguard stand was rolled several times, a truck was damaged, and trash and debris were scattered throughout the beach/park. The tornado moved offshore over the Atlantic Ocean. Maximum sustained winds were near 65 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Florida in 2017Every state in 2017This day in weather historyThe tornado archive for Florida, 2017Warnings in Florida, July 2017
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: 708117, 708119, 708115.