Alert archive / Florida / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 252, NWS Jacksonville, FL

December 3, 2018Clay County, Duval County, Saint Johns County, Florida

NWS Jacksonville, FL issued this severe thunderstorm warning at Dec 3, 2018, 9:39 AM EST for Clay County, Duval County, Saint Johns County, Florida. It was in force for 52 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Dec 3, 2018, 9:39 AM EST (14:39 UTC)
Expired: Dec 3, 2018, 10:31 AM EST
In force: 52 min
Issued by: NWS Jacksonville, FL
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

Counties Clay County, FL, Duval County, FL, Saint Johns County, FL

The radar

The Jacksonville radar (KJAX), 39 km from the middle of the area, began a volume at 14:39 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

Jacksonville, FL (KJAX), launched 12:00Z, 2.7 hours before the alert went out and 41 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1329 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 504 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: 229 m²/s²
0-3 km storm-relative helicity: 240 m²/s²
Significant tornado parameter: 2.1
Supercell composite: 8.1

Open this sounding in Storm Lab

The text

As transmitted.

642 
WUUS52 KJAX 031439
SVRJAX
FLC019-031-109-031545-
/O.NEW.KJAX.SV.W.0252.181203T1439Z-181203T1545Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Jacksonville FL
939 AM EST MON DEC 3 2018

The National Weather Service in Jacksonville has issued a

* Severe Thunderstorm Warning for...
  Northwestern St. Johns County in northeastern Florida...
  Northeastern Clay County in northeastern Florida...
  Southeastern Duval County in northeastern Florida...

* Until 1045 AM EST.

* At 938 AM EST, a severe thunderstorm was located over
  Bellair-Meadowbrook Terrace, or near Orange Park, moving east at 25
  mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Jacksonville, Orange Park, Unf, Mandarin, Fruit Cove, Ponte Vedra
  Beach, Neptune Beach, Sawgrass, Fleming Island and Baymeadows.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Damaging winds and continuous cloud to ground lightning is occurring 
with this storm. Move indoors immediately. Lightning is one of 
nature's leading killers. Remember, if you can hear thunder, you are 
close enough to be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3004 8130 3012 8188 3023 8179 3032 8175
      3031 8136 3010 8130
TIME...MOT...LOC 1438Z 273DEG 23KT 3019 8177 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

SHASHY

4 follow-up statements

184 
WWUS52 KJAX 031450
SVSJAX

Severe Weather Statement
National Weather Service Jacksonville FL
950 AM EST MON DEC 3 2018

FLC019-031-109-031545-
/O.CON.KJAX.SV.W.0252.000000T0000Z-181203T1545Z/
St. Johns FL-Clay FL-Duval FL-
950 AM EST MON DEC 3 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 AM EST
FOR NORTHWESTERN ST. JOHNS...NORTH CENTRAL CLAY AND SOUTHEASTERN
DUVAL COUNTIES...

At 949 AM EST, a severe thunderstorm was located over Nas Jax, or
over Orange Park, moving east at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Orange Park, Unf, Mandarin, Fruit Cove, Ponte Vedra Beach, Neptune
Beach, Sawgrass, Baymeadows, Nocatee and Ortega.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and deadly cloud to ground
lightning. Seek shelter inside a well-built structure. Stay away from
windows.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3004 8130 3013 8183 3022 8177 3031 8174
      3031 8136 3010 8130
TIME...MOT...LOC 1449Z 266DEG 26KT 3020 8168 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

SHASHY

657 
WWUS52 KJAX 031504
SVSJAX

Severe Weather Statement
National Weather Service Jacksonville FL
1004 AM EST MON DEC 3 2018

FLC019-031514-
/O.CAN.KJAX.SV.W.0252.000000T0000Z-181203T1545Z/
Clay FL-
1004 AM EST MON DEC 3 2018

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL CLAY COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 3004 8130 3013 8168 3018 8166 3028 8164
      3031 8136 3010 8130
TIME...MOT...LOC 1504Z 273DEG 23KT 3020 8158 

$$

FLC031-109-031545-
/O.CON.KJAX.SV.W.0252.000000T0000Z-181203T1545Z/
St. Johns FL-Duval FL-
1004 AM EST MON DEC 3 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 AM EST
FOR NORTHWESTERN ST. JOHNS AND SOUTHEASTERN DUVAL COUNTIES...

At 1004 AM EST, a severe thunderstorm was located near Baymeadows, or
near Mandarin, moving east at 25 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Mandarin, Unf, Ponte Vedra Beach, Fruit Cove, Palm Valley, Sawgrass,
Baymeadows, Nocatee, Bayard and Durbin.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and deadly cloud to ground
lightning. Seek shelter inside a well-built structure. Stay away from
windows.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3004 8130 3013 8168 3018 8166 3028 8164
      3031 8136 3010 8130
TIME...MOT...LOC 1504Z 273DEG 23KT 3020 8158 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

SHASHY

870 
WWUS52 KJAX 031519
SVSJAX

Severe Weather Statement
National Weather Service Jacksonville FL
1019 AM EST MON DEC 3 2018

FLC031-109-031545-
/O.CON.KJAX.SV.W.0252.000000T0000Z-181203T1545Z/
St. Johns FL-Duval FL-
1019 AM EST MON DEC 3 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 AM EST
FOR NORTHERN ST. JOHNS AND SOUTHEASTERN DUVAL COUNTIES...

At 1018 AM EST, a severe thunderstorm was located over Ponte Vedra 
Beach, moving east at 15 mph. Additional storms were located further 
west over southern Duval county.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
Unf, Ponte Vedra Beach, Palm Valley, Sawgrass, Baymeadows and San
Pablo.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3010 8130 3017 8164 3028 8163 3031 8136
TIME...MOT...LOC 1518Z 280DEG 13KT 3022 8141 

HAIL...<.75IN
WIND...60MPH
 
$$

SHASHY

112 
WWUS52 KJAX 031531
SVSJAX

Severe Weather Statement
National Weather Service Jacksonville FL
1031 AM EST MON DEC 3 2018

FLC031-109-031540-
/O.CAN.KJAX.SV.W.0252.000000T0000Z-181203T1545Z/
St. Johns FL-Duval FL-
1031 AM EST MON DEC 3 2018

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN ST. JOHNS AND
SOUTHEASTERN DUVAL COUNTIES IS CANCELLED...
        
The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning has 
been cancelled.  However gusty winds are still possible with 
additional showers and thunderstorms over southeast Duval and 
northern St Johns counties.

LAT...LON 3010 8130 3017 8164 3028 8163 3031 8136
TIME...MOT...LOC 1530Z 273DEG 23KT 3022 8133 

$$

SHASHY

The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 3, 3:47 AM EST	Severe Thunderstorm Warning	JAX	Hamilton	28 min
Dec 3, 5:39 AM EST	Special Weather Statement	JAX	Suwannee	36 min
Dec 3, 5:46 AM EST	Tornado Warning	JAX	Columbia, Suwannee	29 min
Dec 3, 6:12 AM EST	Severe Thunderstorm Warning	JAX	Columbia, Suwannee	33 min
Dec 3, 6:17 AM EST	Special Marine Warning	JAX		58 min
Dec 3, 6:39 AM EST	Special Weather Statement	JAX	Baker, Columbia	66 min
Dec 3, 6:58 AM EST	Tornado Warning	JAX	Columbia, Suwannee	17 min
Dec 3, 7:00 AM EST	Severe Thunderstorm Warning	JAX	Baker, Columbia	30 min
Dec 3, 7:09 AM EST	Special Marine Warning	JAX		66 min
Dec 3, 7:24 AM EST	Severe Thunderstorm Warning	JAX	Columbia, Gilchrist, Suwannee	51 min
Dec 3, 7:46 AM EST	Special Weather Statement	JAX	Union	44 min
Dec 3, 7:56 AM EST	Special Weather Statement	JAX	Baker	49 min
Dec 3, 8:14 AM EST	Special Marine Warning	JAX		30 min
Dec 3, 8:32 AM EST	Special Weather Statement	JAX	Nassau	43 min
Dec 3, 8:42 AM EST	Special Weather Statement	JAX	Baker, Clay, Union	48 min
Dec 3, 8:58 AM EST	Severe Thunderstorm Warning	JAX	Baker, Bradford, Clay, Duval, Union	47 min
Dec 3, 9:11 AM EST	Special Weather Statement	JAX	Duval	34 min
Dec 3, 9:13 AM EST	Special Marine Warning	JAX		92 min
Dec 3, 9:21 AM EST	Severe Thunderstorm Warning	JAX	Baker, Bradford, Clay, Duval	39 min
Dec 3, 9:47 AM EST	Areal Flood Advisory	JAX	Clay, Duval	88 min
Dec 3, 10:33 AM EST	Special Weather Statement	JAX	Bradford	42 min
Dec 3, 10:37 AM EST	Special Marine Warning	JAX		53 min
Dec 3, 10:55 AM EST	Special Weather Statement	JAX	Duval	35 min
Dec 3, 11:10 AM EST	Areal Flood Warning	JAX	Clay, Duval, Saint Johns	110 min
Dec 3, 11:17 AM EST	Special Weather Statement	JAX	Duval	13 min
Dec 3, 11:32 AM EST	Special Marine Warning	JAX		58 min
Dec 3, 11:55 AM EST	Special Weather Statement	JAX	Marion	20 min
Dec 3, 11:56 AM EST	Special Weather Statement	JAX	Marion	34 min
Dec 3, 12:17 PM EST	Special Weather Statement	JAX	Flagler	28 min
Dec 3, 4:57 PM EST	Special Weather Statement	JAX	Clay	33 min
Dec 3, 5:26 PM EST	Special Weather Statement	JAX	Duval	34 min

Nearby

Severe Thunderstorm Warnings in Florida, 2018 Every 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.