Surface high pressure centered over the Appalachians gradually weakened and shifted southward which relaxed the pressure gradient over the region and weakened the strong |northeasterly wind event into the evening. Breezy northeasterly winds continued along the coast with gusts up to 30-35 mph.
Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. 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.
Surface high pressure centered over the Appalachians gradually weakened and shifted southward which relaxed the pressure gradient over the region and weakened the strong |northeasterly wind event into the evening. Breezy northeasterly winds continued along the coast with gusts up to 30-35 mph. Coastal hazards including coastal flooding, high surf, and high risk of rip currents continued.
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 Sep 22, 6:25 AM EST, 5 minutes earlier.
Area Forecast Discussion
National Weather Service Jacksonville FL
725 AM EDT Tue Sep 22 2020
.AVIATION...
[Through 12Z Wednesday]
VFR conditions forecast through the period. Breezy northeasterly
winds around 15 knots with gusts to around 25 knots will begin to
relax this afternoon as high pressure builds into the area. Winds
will become light tonight, except at KSGJ where winds will remain
5-10 knots overnight. Scattered showers are forecast to remain
south of KSGJ through the period.
&&
.PREV DISCUSSION [409 AM EDT]...
.NEAR TERM [Through Tonight]...
Surface high pressure centered over the Appalachians will
gradually weaken and shift southward relaxing the gradient over
the region. This will bring an end to the prolonged strong
northeasterly winds by this evening. Breezy northeasterly winds
will continue along the coast into this afternoon with gusts up to
30-35 mph. Our many coastal hazards including coastal flooding,
high surf, and high risk of rip currents continue today with
hazards beginning to subside over coastal Georgia later today.
Generally, rain free day with a stable, dry airmass in place.
Onshore flow will allow for isolated light showers to move over
northeast Florida coast. Temperatures will be cooler than normal
with highs today in the mid 70s to low 80s and lows tonight in the
upper 50s to upper 60s.
.SHORT TERM [Wednesday Through Thursday]...
High pressure over the Carolinas will shift offshore into the Wrn
Atlc through the short term period with onshore steering flow
becoming more southerly. This will slowly usher in a more moist
airmass and expect isolated shower activity possible by Thursday
afternoon and evening time frame. Otherwise mainly dry weather
continues with a return to more seasonable September temps with
Highs in the lower to middle 80s on Wednesday, then into the
mid/upper 80s for Thursday. Lows will generally be in the 60s Wed
Night, then much warmer Thu Night in the upper 60s/near 70 inland
and middle 70s coast.
.LONG TERM [Friday Through Monday]...
Generally warmer, wetter and more humid unsettled period as deeper
tropical moisture (PWATs of 2 inches or higher) pushes back into
the region from the West and Southwest, while trough of low
pressure develops at the surface in association with possible
disturbance in the Eastern Gomex, all of this combined with
daytime heating with above normal Max temps back into the 85 to 90
degree range will lead to daily scattered to numerous showers,
mainly during the afternoon hours with a few embedded storms at
times. Long range models still struggling to capture any specifics
during this period but overall daily rainfall chances in the
40-60% range.
.MARINE...
The high pressure ridge to our north will gradually sink south
and weaken over the next few days. Northeast winds at 20 to 25
knots with gusts to 30 knots this morning will gradually subside
through the day. Very hazardous seas will take longer to lower,
with small craft advisories continuing through at least Wednesday
evening.
Rip Currents: High risk of rip currents in effect for NE FL and
SE GA beaches through Wednesday. High surf advisory in effect
along NE FL beaches through Wednesday, along SE GA beaches through
this morning.
Coastal Flood: With multiple sites recently cresting into moderate
levels with this past high tide cycle, decided to upgrade back to
a Coastal Flood Warning for Jacksonville southward due to the
potential for moderate flooding from trapped tides in the ICWW and
St. Johns River for today's high tide cycle. Today, peak tide
levels could reach 1.5-2.5 ft MHHW along the St. Johns River and
ICWW. Due to the weakening onshore winds, minor coastal flooding
is expected along the Atlantic coast with water levels in the 1-2
ft MHHW range. Continued gradual decrease in peak tide heights as
onshore flow weakens further, however, elevated tides could
linger in the St. Johns River basin through the week.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 76 57 80 62 83 / 10 0 0 0 20
SSI 77 64 78 69 82 / 10 0 0 10 10
JAX 79 63 82 67 85 / 10 0 0 0 10
SGJ 80 69 82 70 85 / 20 10 0 0 20
GNV 81 64 85 66 87 / 10 0 0 0 20
OCF 83 65 86 67 88 / 20 10 0 0 20
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk through Wednesday evening for Coastal
Duval-Coastal Flagler-Coastal Nassau-Coastal St. Johns.
Coastal Flood Advisory until 11 PM EDT this evening for Coastal
Nassau.
Coastal Flood Warning until 11 PM EDT this evening for Clay-
Coastal Duval-Coastal Flagler-Coastal St. Johns-Inland
Duval-Inland Flagler-Inland St. Johns-Putnam.
High Surf Advisory until 8 PM EDT Wednesday for Coastal Duval-
Coastal Flagler-Coastal Nassau-Coastal St. Johns.
GA...High Rip Current Risk through Wednesday evening for Coastal
Camden-Coastal Glynn.
High Surf Advisory until noon EDT today for Coastal Camden-
Coastal Glynn.
Coastal Flood Advisory until 11 PM EDT this evening for Coastal
Camden-Coastal Glynn.
AM...Small Craft Advisory until 8 PM EDT Wednesday for 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.
&&The national radar mosaic for the moment the first event began.
2 coastal flood. Local standard time, as filed.
At 0730, Emergency Management reported water inundation up to 2 ft in some areas of Flagler Beach, particularly along South Flagler Avenue from 15th Street, and locations southward.
At 1708, Emergency Management reported water over-flowing the banks of Pottsburg Creek near Beach Blvd. Flood water had reach the door of a sporting goods store. The USGS tide gauge at Pottsburg Creek measured a high tide of 2.25 ft MHHW datum, in the moderate flood stage category.
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, September 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: 921732, 921734.