An upper level trough axis was just east or very near the local Atlantic coast with weaker bulk shear in the 0-6 km layer around 30 kts with drier air in place which created strong down drafts in storms.
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.
An upper level trough axis was just east or very near the local Atlantic coast with weaker bulk shear in the 0-6 km layer around 30 kts with drier air in place which created strong down drafts in storms.
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 Jun 20, 12:46 PM EST, 2 hours 26 minutes earlier.
Area Forecast Discussion National Weather Service Jacksonville FL 146 PM EDT Sat Jun 20 2020 .NEAR TERM [Through Tonight]... While the atmosphere has dried out somewhat since yesterday with Precipitable Water Amounts (PWATs) of 1.2 to 1.5 inches across the region, the axis of cooler temps and unstable conds aloft extending southward from the low pressure trof over the Carolinas into coastal SE GA the JAX metro area will still lead to a marginal risk of severe storms with damaging winds to 60 mph and hail still possible this afternoon into the evening and again these will mainly be likely along the US 301/I-95 corridor of SE GA where the more moist airmass is, still some threat into the St Johns River Basin/US 301 corridor of NE FL from JAX southward as sea breeze fronts merge from both coasts over this area. Overall the coverage is expected to be less than Fri afternoon/evening and severe threat slightly lower, but stay tuned for any localized warnings that are issued in rapidly developing storms this afternoon and early evening. Last of evening activity around sunset will be across inland NE FL and generally all quiet conds are expected by Midnight with Mostly Clear skies during the overnight hours and lows in the upper 60s inland and lower to middle 70s along the coast. With less coverage of storms expected today, fog potential not as great tonight as indicated by local Hi-Res models and will leave out of the forecast for now and will be dictated by where storms develop this afternoon. .SHORT TERM [Sunday Through Monday]... Sunday...Drier airmass aloft remains in place as sfc ridge builds south across the FL Peninsula and transient weak High Pressure ridge aloft crosses the region from West to East with warmer and more stable conds. This will lead to below normal rainfall chances in the 10-30% range with best chances in the sea breeze front merger in the US 301 and I-95 zone as light SW steering flow continues to keep the East Coast Sea Breeze from moving too far inland. Highs in the lower to middle 90s inland and near 90 at the coast with Heat Indices around 100 degrees. Monday...Drier airmass will linger across SE GA and will keep rain chances at 20% or less there, while a slight resurgence of moisture from the SW over the FL Peninsula will return NE FL closer to climo rainfall chances in the 30-50% range as sea breeze merger takes place along the US301 corridor and storms then drift back towards the I-95 corridor during the afternoon hours. Cooler temps and more unstable conds aloft will lead to a few strong and isolated svr storms across inland NE FL. The SW steering flow will keep conds Hot with above normal highs in the lower to middle 90s inland and near 90 along the coast with Heat Indices "Feels Like" temps into the 100-103 range. .LONG TERM [Tuesday Through Saturday]... Typical summer-like pattern with weak High Pressure ridge across the FL Peninsula while zonal flow aloft over the SE US will bring a few weakening cold fronts and moisture surges on Wednesday and again late in the period (Fri-Sat). This will lead to generally climo Pops (30-50%) through the period except for brief surges upwards to (Pops 50-70%) when this increased moisture pushes into the region. The mainly westerly steering flow through the period will lead to slightly above normal temps with Highs in the lower to middle 90s inland and near 90 at the Atlc Beaches due to a weakened and slowly moving inland East Coast Sea Breeze. These conds will lead to daily Heat Indices "Feels Like" temps of 100-105 each afternoon. The long range models are suggesting fairly cool mid level (500mb) temps of -8C to -10C and this will likely lead to scattered strong and isolated severe storm potential each afternoon/early evening with damaging wet microburst conds along with hail/locally heavy rainfall threat. Storm activity will continue to be focused into the US 301 and I-95 corridor/Atlc Coast as westerly steering flow keeps best afternoon convergence of sea breeze fronts in this zone. && .AVIATION... [Through 18Z Sunday] The atmosphere is fairly suppressed for summer with PWATs of 1.25 to 1.5 inch. The sea breeze front will be fairly weak today but with interior temperatures in the 90s expect some convection to fire along the Atlantic Sea breeze front later this afternoon and this evening and some "popcorn" pulse convection across the interior. Just looking at about 30% coverage so will use VCTS for the main fields this afternoon into the early evening. With less precipitation today overnight fog will not be as widespread and anticipating 2-5 miles in BR/light fog/mist in the normal locations of KJAX, KVQQ and KGNV for a few hours between 09-13 utc. && .MARINE... Typical South to Southwest flow at 10-15 knots through the period as High Pressure ridge builds just south of the local waters through the period with seas 2-4 ft. Local sea breezes near the coast along with the daily threat of scattered storms nearshore waters during the afternoon/evening hours. The high pressure ridge is strong enough to set up some nocturnal surges of S-SW winds at 15-20 knots, mainly over the offshore waters with seas 3-5 ft, but still too far out for any significant marine headlines, except for the threat of short-fuse Special Marine Warnings for offshore moving storms through the period. Rip Currents: Rip current risk will generally remain on the the lower to marginally moderate end through early next week with breakers/surf in the 1-2 ft range due to offshore flow and a weak sea breeze along the coast through the period. && .FIRE WEATHER... Slightly lower rainfall chances and drier airmass will lead to lower humidities this weekend, not expecting any fire weather headlines over the next week. && .HYDROLOGY... Minor flooding expected to slowly come to an end on the upper Suwannee River Basin later today at White Springs. Minor backwater flooding on the lower Santa Fe River Basin at Three Rivers Estates is looking less likely with each forecast, but is still possible sometime next week. && .PRELIMINARY POINT TEMPS/POPS... AMG 69 94 69 95 71 / 10 30 10 10 10 SSI 74 87 74 90 75 / 10 20 10 10 20 JAX 70 94 71 95 73 / 10 30 10 20 10 SGJ 72 91 72 91 73 / 10 10 10 30 20 GNV 69 95 68 94 71 / 10 10 10 40 10 OCF 69 94 70 94 71 / 10 20 10 50 20 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AM...None. &&
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE JACKSONVILLE FL
1017 AM EDT SAT JUN 20 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0930 PM TSTM WND DMG SCREVEN 31.48N 82.02W
06/19/2020 WAYNE GA PUBLIC
ROOF DAMAGE TO SCREVEN ELEMENTARY SCHOOLS
AUDITORIUM. PHOTOS WERE RELAYED FROM SOCIAL
MEDIA. RADAR ESTIMATED TIME.
&&
KCSpecial Weather Statement National Weather Service Jacksonville FL 330 PM EDT Sat Jun 20 2020 FLZ024-025-124-125-202000- Inland Duval FL-Inland Nassau FL-Coastal Nassau FL-Coastal Duval FL- 330 PM EDT Sat Jun 20 2020 ...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN NASSAU AND NORTHEASTERN DUVAL COUNTIES UNTIL 400 PM EDT... * At 330 PM EDT, National Weather Service meteorologists were tracking a strong thunderstorm near Yulee, or 9 miles south of St. Marys, moving south at 20 mph. * Winds in excess of 45 mph possible with this storm. * Locations impacted include... Yulee and Oceanway. 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. To report severe weather, contact your nearest law enforcement agency. You can also share your report with NWS Jacksonville on Facebook and Twitter. && LAT...LON 3067 8170 3071 8160 3053 8141 3045 8166 TIME...MOT...LOC 1930Z 337DEG 15KT 3063 8164 AK
Special Weather Statement
National Weather Service Jacksonville FL
354 PM EDT Sat Jun 20 2020
GAZ153-154-165-166-202045-
Inland Glynn GA-Inland Camden GA-Coastal Glynn GA-Coastal Camden GA-
354 PM EDT Sat Jun 20 2020
...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN CAMDEN AND
SOUTHWESTERN GLYNN COUNTIES UNTIL 445 PM EDT...
* At 354 PM EDT, National Weather Service meteorologists were
tracking a strong thunderstorm near Waverly, or near Woodbine,
moving east northeast at 15 mph.
* Small hail and winds in excess of 45 mph possible with this storm.
* Locations impacted include...
Brunswick, St. Simons Island, Woodbine, Waverly, Jekyll Island and
Dover Bluff.
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.
To report severe weather, contact your nearest law enforcement
agency. You can also share your report with NWS Jacksonville on
Facebook and Twitter.
&&
LAT...LON 3096 8139 3093 8173 3111 8178 3121 8141
3110 8137
TIME...MOT...LOC 1954Z 247DEG 14KT 3105 8169
AKSpecial Weather Statement
National Weather Service Jacksonville FL
359 PM EDT Sat Jun 20 2020
FLZ025-125-202030-
Inland Duval FL-Coastal Duval FL-
359 PM EDT Sat Jun 20 2020
...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN DUVAL COUNTY UNTIL
430 PM EDT...
* At 359 PM EDT, National Weather Service meteorologists were
tracking a strong thunderstorm over Oceanway, or near Jacksonville
International Arpt, moving south at 20 mph.
* Small hail and winds in excess of 45 mph possible with this storm.
* Locations impacted include...
Jacksonville, Oceanway, Fort Caroline and Tallyrand.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
To report severe weather, contact your nearest law enforcement
agency. You can also share your report with NWS Jacksonville on
Facebook and Twitter.
&&
LAT...LON 3038 8143 3034 8170 3057 8170 3057 8167
3055 8166 3058 8165 3058 8161 3057 8160
3056 8161 3055 8161 3057 8159 3055 8159
3054 8158 3054 8155 3052 8154 3054 8152
TIME...MOT...LOC 1959Z 339DEG 19KT 3050 8163
AKThe Jacksonville radar (KJAX), 5 km away, was scanning. The volume nearest the first event began at 20:10 UTC.
4 thunderstorm wind. Local standard time, as filed.
A tree was blown down over a driveway. The time of damage was based on radar. The cost of damage was unknown but estimated for Storm Data.
Trees were blown down in the Oceanway Village Mobile Home Park. The time of the event was based on radar. The cost of damage was unknown but estimated for Storm Data.
A tree was blown down on a fence near Cimmarone Blvd and Old County Road 210. The time of the event was based on radar.
A tree that was 1 foot in diameter was blown down onto a residence in Bartram Springs.
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, June 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: 894338, 894340, 894341, 894339.