A retrograding upper level low was across the eastern Gulf of Mexico which provided upper level diffluence as an inverted low level trough enhanced coastal convergence along the NE FL coast. Bands of heavy rainfall moved onshore through the day as the inverted trough shifted inland.
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.
A retrograding upper level low was across the eastern Gulf of Mexico which provided upper level diffluence as an inverted low level trough enhanced coastal convergence along the NE FL coast. Bands of heavy rainfall moved onshore through the day as the inverted trough shifted inland.
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 13, 7:45 PM EST, 3 hours 15 minutes earlier.
Area Forecast Discussion National Weather Service Jacksonville FL 845 PM EDT Fri Aug 13 2021 .UPDATE... Inland convection has faded this evening with the loss of diurnal heating and forecast remains on track for just a few isolated showers possible during the overnight hours with scattered showers and isolated storms building over the Atlantic Coastal Waters. Increasing tropical moisture with the TD Fred circulation will lead to morning showers and storms along the Atlc Coast/I-95 corridor by the mid-late morning hours that will press inland during the afternoon hours with peak heating. Expect storm activity to include heavy rainfall and gusty winds but there should be enough movement to keep any flooding issues localized and transitory as convection fades again tomorrow evening. Max temps to reach into the lower 90s well inland, near 90 along the I-95 corridor and St Johns River Basin, with upper 80s at the beaches. && .PREV DISCUSSION [736 PM EDT]... .NEAR TERM [Through Tonight]... Isolated to widely scattered showers and thunderstorms have popped up this afternoon as expected and will continue through the rest of this afternoon and into the early evening hours. Precipitation is expected to dwindle this evening, making way for a mostly dry night. A few showers and potentially a thunderstorm will be possible tonight along the coastal zones and over the Atlantic coastal waters. Winds will become light tonight, and skies will be partly cloudy. Low temperatures tonight will be in the low-to-mid 70s inland and the upper 70s at the coast. .SHORT TERM [Saturday Through Sunday Night]... Saturday, Tropical Cyclone Fred is forecast to move across the FL Keys then into the eastern Gulf of Mexico. A plume of tropical moisture will advect into the area as a mid/upper level tropical trough moves northward over the eastern Gulf of Mexico ahead of Fred. Model guidance suggests PWATs over the area will reach 2-2.2 inches with the highest moisture over our southern zones and along the coast. This will result in increased precipitation chances on Saturday, scattered to numerous showers and thunderstorms are expected. East-southeasterly flow will cause showers and storms to kick off along the coast early then spread inland though the afternoon. Sunday, Fred is forecast to move northwestward across the eastern Gulf towards the FL panhandle. Deep tropical moisture will continue to build over the region, which will continue elevated precipitation chances with numerous to widespread showers and storms expected. The main threat to our area will be heavy rainfall. Grounds across the area are saturated due to well above normal precipitation over the past 30 days, so localized flooding will be a concern. Several rivers are currently experiencing minor to moderate flooding, including the Suwannee, Santa Fe, and St. Marys rivers. Additional rainfall could exacerbate and prolong river flooding. We also can't rule out a few tropical tornadoes as we will be in the front right quadrant of Fred. High temperatures on Saturday will be slightly below to near average in the upper 80s to lower 90s, cooler at the coasts and warmer inland. High temperatures Sunday will be below average with highs only in the middle 80s due to expected cloud cover and precipitation. Overnight low temperatures will be near normal in the 70s. .LONG TERM [Monday Through Friday]... Fred is forecast to move inland near the FL panhandle on Monday then continue moving north while weakening through midweek. Even as Fred moves away from the area, tropical moisture will linger and continue increased precipitation chances through the week. Numerous showers and thunderstorms will be possible each day, with highest chances during peak daytime heating hours. Additional rainfall could continue localized flooding and river flooding concerns. High temperatures through the long term period will trend slightly below to near normal due to expected cloud and precipitation coverage. Low temperatures will trend near normal through the period. .AVIATION... [Through 00Z Sunday] Majority of convection has shifted west of all TAF sites and focus returns to looking towards the SE with any shower activity coming off the Atlc and up the FL peninsula around TD Fred circulation which should generally not take place until late tonight with VFR conds until then with first round of showers starting at SGJ by 09-12Z time frame, then at CRG/SSI by 10-13Z time frame, then JAX/VQQ/GNV by the 11-14Z, this will be followed by predominant shower activity with embedded storms at all NE FL TAF sites with MVFR CIGS/VSBYS and gusty winds to at least 25 knots. This will occur first at SGJ, then move NE to the remainder of the TAF sites, for now have kept the PROB30 groups that will likely need to be upgraded to TEMPO groups in last issuances. Some improvement will be felt at the Atlc Beaches TAF sites of SGJ/SSI as sea breeze/convection pushes further inland after 19-21Z and expect a return to just VCSH with VFR conds at the end of the TAF period. .MARINE... The local waters will be sandwiched between low pressure associated with Tropical Cyclone Fred in the Gulf of Mexico and the Bermuda high through early next week. Fred is expected to be to the southwest Saturday into Sunday, then to the west Sunday night into Monday, then to the northwest Tuesday. The Bermuda high will be to the north tonight then shift to the northeast Saturday and remain there through midweek. This pattern will result in southeasterly winds that will be slightly elevated at 10-15 knots and seas 3-5 feet through Tuesday. Daily chances for showers and thunderstorms will continue. Interests should continue to monitor the National Hurricane Center forecast on Fred. Rip Currents: Onshore flow will result in a Moderate Risk of rip currents continuing through the weekend. .FIRE WEATHER... Deep tropical moisture will move into the area this weekend, which will keep RH above critical values and increase precipitation chances. The I-75 corridor is expected to see increased winds on Sunday as Fred passes to the west, which will result in increased transport winds. Interests should continue to monitor the National Hurricane Center for information on Tropical Cyclone Fred. .HYDROLOGY... River flooding continues along the Suwannee, Santa Fe, St. Marys, Satilla, and Ichetucknee Rivers. Moderate flooding is occurring on the Santa Fe River at Fort White and Three Rivers Estates and on the Ichetucknee River near Ichetucknee Springs State Park, and moderate flooding is forecast on the Suwannee River at Suwannee Springs early next week. Tropical moisture will work its way into the area this weekend ahead of and during Fred's movement along the eastern Gulf waters. This is expected to bring scattered to numerous showers Saturday and numerous to widespread showers on Sunday. Widespread rainfall totals are forecast to be in the 1-3" range, but isolated higher totals will be possible, with the highest totals expected near the I-75 corridor. This will exacerbate ongoing river flooding, particularly in the Suwannee and Santa Fe River basins and could also lead to localized flooding, especially in low lying, urban, or poor-draining areas. The Weather Prediction Center has the majority of the I-75 corridor in a slight risk of excessive rainfall (i.e. exceeding flash flood guidance) on Sunday as Fred makes its closest approach to the region. The rest of our area is in a marginal risk of excessive rainfall on Sunday. && .PRELIMINARY POINT TEMPS/POPS... AMG 72 92 73 88 72 / 10 20 40 80 40 SSI 78 87 78 86 77 / 10 30 50 80 50 JAX 75 90 75 88 75 / 10 50 50 80 40 SGJ 76 88 76 86 76 / 20 60 50 70 40 GNV 73 90 73 85 73 / 10 70 50 80 40 OCF 73 90 73 85 73 / 20 90 60 80 40 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AM...None. &&
PRELIMINARY LOCAL STORM REPORT
National Weather Service Jacksonville FL
726 PM EDT FRI AUG 13 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0445 PM TSTM WND DMG 5 NW COLUMBIA 30.13N 82.76W
08/13/2021 Columbia FL EMERGENCY MNGR
TREE FELL ON HOUSE AND POWER LINES ON SW SALEM ROAD OFF
COUNTY ROAD 242.
&&
MZSpecial Weather Statement
National Weather Service Jacksonville FL
746 PM EDT Fri Aug 13 2021
GAZ132-133-140015-
Coffee GA-Jeff Davis GA-
746 PM EDT Fri Aug 13 2021
...A strong thunderstorm will impact portions of central Coffee and
southwestern Jeff Davis Counties through 815 PM EDT...
At 746 PM EDT, Doppler radar was tracking a strong thunderstorm over
Broxton, moving west at 25 mph.
HAZARD...Winds in excess of 40 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Broxton, Ambrose and Pridgen.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.
&&
LAT...LON 3151 8308 3156 8306 3161 8306 3161 8305
3162 8305 3162 8303 3163 8303 3163 8301
3166 8301 3166 8300 3178 8300 3172 8276
3154 8278 3150 8310
TIME...MOT...LOC 2346Z 092DEG 23KT 3164 8289
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH
CORLESSThe national radar mosaic for the moment the first event began.
8 heavy rain, 1 flood. Local standard time, as filed.
An observer measured 3.98 inches of storm total rainfall. About 1.48 inches fell within the past 40 minutes.
Storm total rainfall from the NAS Jacksonville AWOS was 4.03 inches.
A mesonet station in Jacksonville Beach measured storm total rainfall of 2.96 inches.
Over the past 3 hours, 2.90 inches of rainfall was measured.
A private weather station near Russel Road and Henley Road measured 4.83 inches of rainfall in the past 2 hours.
An observer measured 2.5 inches of storm total rainfall.
A private weather station measured 4.07 inches of rainfall since 2:30 pm.
A private weather station measured 4.01 inches of rainfall between 2:45 pm and 5:19 pm.
Minor road flooding was reported along South Highway 314 A between Highway 464 C and Highway 40.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Florida in 2021Every state in 2021This day in weather historyWarnings in Florida, August 2021
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: 973060, 973061, 973062, 973057, 973059, 973058, 973064, 973063, 973056.