Alert archive / Florida / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 222, NWS Jacksonville, FL

October 9, 2018Duval County, Nassau County, Florida

NWS Jacksonville, FL issued this severe thunderstorm warning at Oct 9, 2018, 10:15 AM EDT for Duval County, Nassau County, Florida. It was in force for 16 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Oct 9, 2018, 10:15 AM EDT (14:15 UTC)
Expired
Oct 9, 2018, 10:31 AM EDT
In force
16 min
Issued by
NWS Jacksonville, FL
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Duval County, FL, Nassau County, FL

The radar

The Jacksonville radar (KJAX), 1 km from the middle of the area, began a volume at 14:15 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 2.3 hours before the alert went out and 248 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Tallahassee Rgnl, FL at 12:00Z on 2018-10-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 270 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tallahassee Rgnl, FL at 12:00Z on 2018-10-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 180 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
270 J/kg
Mixed-layer CIN
-11 J/kg
Mixed-layer LCL
573 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
180 m²/s²
0-3 km storm-relative helicity
209 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.2

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at Oct 9, 9:12 AM EDT, 1 hour 3 minutes earlier.

Area forecast discussion, Oct 9, 9:12 AM EDT, 1 hour 3 minutes before
Area Forecast Discussion
National Weather Service Jacksonville FL
912 AM EDT Tue Oct 9 2018

.UPDATE...

Gusty showers will continue to move West off the Atlantic this
morning. Strong wind gusts will be possible with the heavier
showers, especially near the coast. The chance for thunderstorms
will increase into the afternoon, due to diurnal instability, with
these having the potential to produce strong wind gusts as well.

Temperatures will moderate into the middle 80s.

&&

.AVIATION.../12z TAF period/...

Gusty showers and storms are expected this afternoon and evening.
This potential is expected to be lower Tonight, but the potential
for a gusty shower can not be ruled out through the night.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  85  75  88  76 /  70  40  80  80
SSI  82  77  86  78 /  70  60  70  80
JAX  85  77  89  77 /  60  30  70  60
SGJ  84  80  89  78 /  70  30  60  40
GNV  87  77  88  77 /  40  30  70  60
OCF  88  77  89  77 /  30  30  70  60

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...Tropical Storm Watch for Columbia-Gilchrist-Hamilton-Suwannee.

     High Rip Current Risk through late Wednesday night for Coastal
     Duval-Coastal Flagler-Coastal Nassau-Coastal St. Johns.

     High Surf Advisory until 10 AM EDT Thursday for Coastal Duval-
     Coastal Flagler-Coastal Nassau-Coastal St. Johns.

     Coastal Flood Advisory until 6 AM EDT Thursday for Clay-Coastal
     Duval-Coastal Flagler-Coastal Nassau-Coastal St. Johns-
     Inland Duval-Inland St. Johns.

GA...Tropical Storm Watch for Appling-Atkinson-Bacon-Brantley-
     Charlton-Clinch-Coastal Camden-Coastal Glynn-Coffee-Echols-
     Inland Camden-Inland Glynn-Jeff Davis-Pierce-Ware-Wayne.

     High Rip Current Risk through late Wednesday night for Coastal
     Camden-Coastal Glynn.

     High Surf Advisory until 10 AM EDT Thursday for Coastal Camden-
     Coastal Glynn.

     Coastal Flood Advisory until 6 AM EDT Thursday for Coastal
     Camden-Coastal Glynn.

AM...Tropical Storm Watch for Coastal waters from Altamaha Sound to
     Fernandina Beach FL out 20 NM-Waters from Altamaha Sound GA
     to Fernandina Beach FL from 20 to 60 NM.

     Small Craft Advisory until 3 PM EDT Thursday for 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 Fernandina Beach to St. Augustine FL from 20 to
     60 NM-Waters from St. Augustine to Flagler Beach FL from 20
     to 60 NM.

&&

23//

In the hours before

Local storm report, Oct 9, 9:09 AM EDT, 1 hour 6 minutes before
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Special weather statement, Oct 9, 9:34 AM EDT, 41 minutes before
Special Weather Statement
National Weather Service Jacksonville FL
934 AM EDT TUE OCT 9 2018

FLZ033-038-124-125-133-138-091430-
Coastal Flagler FL-Coastal St. Johns FL-Inland Flagler FL-
Coastal Duval FL-Coastal Nassau FL-Inland St. Johns FL-
934 AM EDT TUE OCT 9 2018

...SIGNIFICANT WEATHER ADVISORY FOR FLAGLER...NORTHEASTERN NASSAU...
ST. JOHNS AND EASTERN DUVAL COUNTIES UNTIL 1030 AM EDT...

At 934 AM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from 7 miles northeast of Barberville to 18 miles
east of Little Talbot Island. Movement was west at 30 mph.

Wind gusts of 40 to 50 mph can be expected along with possible minor
wind damage.

Locations impacted include...
Jacksonville, Palm Coast, St. Marys, Saint Augustine, Fernandina
Beach, Flagler Beach, Bunnell, Hastings, Unf and Fruit Cove.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with these storms, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 2926 8115 2926 8141 2940 8142 2940 8148
      2949 8152 2976 8153 2997 8161 3004 8169
      3012 8168 3011 8151 3032 8168 3052 8163
      3075 8168 3072 8161 3075 8158 3075 8154
      3073 8142 3025 8135 2952 8110
TIME...MOT...LOC 1334Z 098DEG 26KT 2927 8134 3048 8111

ENYEDI
Local storm report, Oct 9, 9:37 AM EDT, 38 minutes before
PRELIMINARY LOCAL STORM REPORT
National Weather Service Jacksonville FL
937 AM EDT TUE OCT 9 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0920 AM     TSTM WND GST     VILANO BEACH            29.94N 81.30W
10/09/2018  M43 MPH          ST. JOHNS          FL   MESONET

            MESONET SITE AT VILANO BEACH MEASURED 36 MPH WINDS WITH
            GUST TO 43 MPH

&&

AENYEDI
Special weather statement, Oct 9, 10:10 AM EDT, 5 minutes before
Special Weather Statement
National Weather Service Jacksonville FL
1010 AM EDT TUE OCT 9 2018

FLZ024-025-124-125-091500-
Inland Duval FL-Inland Nassau FL-Coastal Duval FL-Coastal Nassau FL-
1010 AM EDT TUE OCT 9 2018

...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL NASSAU AND CENTRAL DUVAL
COUNTIES UNTIL 1100 AM EDT...

At 1009 AM EDT, a strong band of showers extended along a line
extending from 6 miles northwest of Little Talbot Island to near Nas
Jax. Movement was northwest at 25 mph.

Wind gusts of 45 to 55 mph can be expected along with possible minor
wind damage. A wind gust of 51 mph was reported at 10 am at Huguenot
Park.

Locations impacted include...
Jacksonville, Callahan, Jacksonville International Arpt, Arlington,
Yulee, Cisco Gardens, Ortega, Fort Caroline, Bryceville and Nassau
Village-Ratliff.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with these storms, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3075 8177 3033 8200 3021 8159 3053 8141
TIME...MOT...LOC 1409Z 127DEG 23KT 3053 8149 3025 8164

ENYEDI
Local storm report, Oct 9, 10:11 AM EDT, 4 minutes before
PRELIMINARY LOCAL STORM REPORT
National Weather Service Jacksonville FL
1011 AM EDT TUE OCT 9 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1000 AM     TSTM WND GST     2 N MAYPORT             30.42N 81.41W
10/09/2018  M51 MPH          AMZ452             FL   MESONET

            WEATHERFLOW SITE MEASURED A PEAK WIND GUST OF 51 MPH.

&&

RBRICKER
Local storm report, Oct 9, 10:15 AM EDT, 0 minutes before
PRELIMINARY LOCAL STORM REPORT
National Weather Service Jacksonville FL
1015 AM EDT TUE OCT 9 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0920 AM     TSTM WND GST     2 NW ST. AUGUSTINE      29.92N 81.33W
10/09/2018  M43 MPH          St. Johns          FL   MESONET

            WEATHERFLOW SITE MEASURED A PEAK WIND GUST OF 43 MPH.

&&

RBRICKER

The office that day

Everything else NWS Jacksonville, FL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 9, 3:07 AM EDTHigh Surf AdvisoryJAXDuval, Flagler, Nassau49 hr
Oct 9, 4:45 AM EDTSpecial Marine WarningJAX90 min
Oct 9, 6:55 AM EDTSpecial Marine WarningJAX65 min
Oct 9, 6:58 AM EDTSpecial Weather StatementJAXSaint Johns32 min
Oct 9, 7:27 AM EDTSpecial Marine WarningJAX2 hr
Oct 9, 7:36 AM EDTSpecial Weather StatementJAXFlagler24 min
Oct 9, 8:59 AM EDTSpecial Weather StatementJAXDuval31 min
Oct 9, 9:02 AM EDTSpecial Weather StatementJAXSaint Johns28 min
Oct 9, 9:29 AM EDTSpecial Marine WarningJAX4 hr
Oct 9, 9:34 AM EDTSpecial Weather StatementJAXDuval, Flagler, Saint Johns56 min
Oct 9, 9:49 AM EDTTornado WarningJAXDuval, Saint Johns8 min
Oct 9, 10:10 AM EDTSpecial Weather StatementJAXDuval, Nassau50 min
Oct 9, 10:30 AM EDTSpecial Weather StatementJAXDuval, Flagler, Nassau, Saint Johns90 min
Oct 9, 11:18 AM EDTTropical Storm WarningJAXGilchrist, Suwannee42 hr
Oct 9, 12:40 PM EDTSpecial Weather StatementJAXFlagler50 min
Oct 9, 1:05 PM EDTSpecial Weather StatementJAXDuval, Nassau85 min
Oct 9, 1:18 PM EDTSpecial Marine WarningJAX4 hr
Oct 9, 5:13 PM EDTSpecial Weather StatementJAXMarion47 min
Oct 9, 11:43 AM EDTCoastal Flood WarningJAXCamden, Glynn28 hr
Oct 9, 12:07 PM EDTSpecial Weather StatementJAXCamden, Glynn53 min
Oct 9, 2:57 PM EDTSpecial Weather StatementJAXBrantley, Camden, Charlton48 min
Oct 9, 3:43 PM EDTSpecial Weather StatementJAXBrantley, Pierce47 min
Oct 9, 4:59 PM EDTAreal Flood AdvisoryJAXBrantley, Camden, Glynn, Pierce, Wayne2 hr

Nearby

Severe Thunderstorm Warnings in Florida, 2018Every severe thunderstorm warning in 2018

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.