Alert archive / Florida / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 147, NWS Jacksonville, FL

July 22, 2018Duval County, Florida

NWS Jacksonville, FL issued this severe thunderstorm warning at Jul 22, 2018, 12:43 PM EDT for Duval County, Florida. It was in force for 32 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: Jul 22, 2018, 12:43 PM EDT (16:43 UTC)
Expired: Jul 22, 2018, 1:15 PM EDT
In force: 32 min
Issued by: NWS Jacksonville, FL
Area: Storm-based polygon
Hail: 1.0 in
Wind: 70.0 mph

County Duval County, FL

The radar

The Jacksonville radar (KJAX), 17 km from the middle of the area, began a volume at 16:46 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 22, 11:15 AM EDT	Severe Thunderstorm Watch	SPC	10 hr

The nearest sounding before it

Jacksonville, FL (KJAX), launched 12:00Z, 4.7 hours before the alert went out and 19 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: 2402 J/kg
Mixed-layer CIN: -52 J/kg
Mixed-layer LCL: 848 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 133 m²/s²
0-3 km storm-relative helicity: 130 m²/s²
Significant tornado parameter: 1.0
Supercell composite: 6.1

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 Jul 22, 8:54 AM EDT, 3 hours 49 minutes earlier.

Area forecast discussion, Jul 22, 8:54 AM EDT, 3 hours 49 minutes before

Area Forecast Discussion
National Weather Service Jacksonville FL
854 AM EDT Sun Jul 22 2018

.UPDATE...
Today will start out with low cloudiness across the Suwannee
Valley and southeastern Georgia which should burn off and lift
into a cumulus deck between 9 and 10 a.m. That low cloudiness may
inhibit destabilization over the Nature Coast counties with
convection initiating closer to Interstate 75 and the Florida-
Georgia State Line later this morning. With more stable
conditions near the Altamaha River we should take a day off from
major convection in that area but from about Waycross southward we
should see an active day. Mostly clear conditions are evident
south and east of a line from Fernandina Beach to Trenton and this
area will heat up and destabilize rapidly today. Expect to see
heat index values rise into the 103-108 degree range by late
morning.

We currently have max surface based CAPEs over 5000 J/KG over the
Gulf and Nature Coast with some convection over the Apalache Bay
area. By noon that area will expand to cover the entire north-
central Florida Peninsula area. 0-3 km storm relative helicity is
only in the 100 to 150 range so not looking at a tornadic day
with the greatest threat likely to be strong down busts.

The main flow will be from the west to the east across the area
with the cells moving east at 20 to 30 mph also increasing
confidence in linear downburst with and ahead of cells. So expect
early convective initiation along the Florida-Georgia State Line
moving east through the Jacksonville Metro Area and over the
coastal waters. The convection will then fill in over most of the
area south of waycross by early afternoon with cells again moving
over the coastal waters.

&&

.AVIATION...
Showers and thunderstorms will develop near and over almost all of
the fields later this morning and continue through most of the
day. Low ceilings in the 1-2.5 kft range, reduced 1-3sm
visibilities and downburst conditions will be the primary threat.
Wind gusts of 30 to 40 knots in and near convection are definitely
possible with a slight risk of severe conditions at all fields.

&&

.MARINE...
Going to be a deceptive day for boaters with conditions looking
good during the morning hours but convective initiation over the
land areas this morning will cover the Intracoastal Waterway and
coastal waters by early afternoon. Strong possibility of wind gusts
near or above 35 knots with those storms and boaters should be
ready to make for shelter/port with short notice today. Not going
to be a good day to be well offshore today. Plan to issue a Marine
Weather Statement for this possibility after completing the AFD.

Southwest flow will continue as low pressure develops over
the Carolinas and drops southward early next week. Speeds generally
in the 10-15 knot range may increase to cautionary levels offshore
early next week. Offshore moving storms with wind gusts of 35-50
knots will be possible today and possibly on Monday and
mariners/boaters will need to be prepared for rapidly changing
weather conditions.

Rip Currents: Low risk today due to offshore flow. Have gone with a
moderate risk Ne Fl beaches Monday as the flow increases and becomes
onshore in the afternoon.

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  92  72  90  73 /  40  40  50  30
SSI  93  76  88  77 /  40  40  50  50
JAX  94  73  91  74 /  40  40  50  30
SGJ  94  76  90  75 /  60  40  40  20
GNV  92  74  90  73 /  60  40  40  20
OCF  90  75  89  74 /  60  50  40  30

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AM...None.
&&

Sandrik/Bricker

In the hours before

Special weather statement, Jul 22, 11:10 AM EDT, 1 hour 33 minutes before

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Special weather statement, Jul 22, 12:05 PM EDT, 38 minutes before

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Special weather statement, Jul 22, 12:18 PM EDT, 25 minutes before

Special Weather Statement
National Weather Service Jacksonville FL
1218 PM EDT SUN JUL 22 2018

FLZ025-032-033-037-125-133-138-221700-
Coastal Flagler FL-Coastal St. Johns FL-Inland Duval FL-Putnam FL-
Coastal Duval FL-Clay FL-Inland St. Johns FL-
1218 PM EDT SUN JUL 22 2018

...SIGNIFICANT WEATHER ADVISORY FOR NORTH CENTRAL FLAGLER...ST.
JOHNS...NORTHEASTERN PUTNAM...NORTHEASTERN CLAY AND SOUTHEASTERN
DUVAL COUNTIES UNTIL 100 PM EDT...

At 1218 PM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from Ortega to near Bostwick. Movement was east at
35 mph.

Nickel size hail, excessive cloud-to-ground lightning and wind gusts
of 45 to 55 mph can be expected along with possible minor damage.

Locations impacted include...
Saint Augustine, Palatka, Orange Park, Green Cove Springs, Hastings,
East Palatka, Unf, Mandarin, Fruit Cove and Ponte Vedra Beach.

A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
northeastern Florida.

LAT...LON 2965 8132 2964 8132 2964 8174 3024 8176
      3041 8137 3024 8134 2964 8115
TIME...MOT...LOC 1618Z 270DEG 29KT 3026 8168 2972 8165

SANDRIK

Local storm report, Jul 22, 12:39 PM EDT, 4 minutes before

PRELIMINARY LOCAL STORM REPORT
National Weather Service Jacksonville FL
1239 PM EDT SUN JUL 22 2018

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

1105 AM     TSTM WND GST     VILANO BEACH            29.94N 81.30W
07/22/2018  M40 MPH          ST. JOHNS          FL   MESONET

            A WEATHER FLOW SITE MEASURED A WIND GUST OF 40 MPH.

&&

RBRICKER

Special weather statement, Jul 22, 12:41 PM EDT, 2 minutes before

Special Weather Statement
National Weather Service Jacksonville FL
1241 PM EDT SUN JUL 22 2018

FLZ031-036-221730-
Alachua FL-Bradford FL-
1241 PM EDT SUN JUL 22 2018

...SIGNIFICANT WEATHER ADVISORY FOR ALACHUA AND BRADFORD COUNTIES
UNTIL 130 PM EDT...

At 1240 PM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from Lake Butler to near Florahome. Movement was
northeast at 25 mph.

Nickel size hail and wind gusts of 45 to 55 mph can be expected along
with possible minor damage.

Locations impacted include...
Gainesville, Starke, Alachua, High Springs, Hawthorne, Archer,
University Of Florida, New River, Beasley and Rochelle.

A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
northern Florida.

LAT...LON 2943 8221 2946 8219 2949 8222 2948 8255
      2954 8256 2955 8266 2983 8266 2986 8260
      2994 8252 2992 8242 2993 8236 2996 8234
      2996 8231 3003 8226 3004 8222 3010 8217
      3008 8205 2943 8207
TIME...MOT...LOC 1640Z 236DEG 21KT 2999 8233 2971 8184

SANDRIK

Local storm report, Jul 22, 12:43 PM EDT, 0 minutes before

PRELIMINARY LOCAL STORM REPORT
National Weather Service Jacksonville FL
1243 PM EDT SUN JUL 22 2018

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

1215 PM     TSTM WND GST     5 W EAST PALATKA        29.66N 81.69W
07/22/2018  M41 MPH          Putnam             FL   AWOS

            PALATKA AIRPORT AWOS SITE MEASURED A WIND GUST OF 41 MPH.

&&

RBRICKER

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 22, 11:07 AM EDT	Special Marine Warning	JAX		53 min
Jul 22, 11:10 AM EDT	Special Weather Statement	JAX	Alachua, Bradford, Union	50 min
Jul 22, 11:21 AM EDT	Severe Thunderstorm Warning	JAX	Alachua, Bradford, Gilchrist	39 min
Jul 22, 11:36 AM EDT	Severe Thunderstorm Warning	JAX	Columbia, Suwannee	39 min
Jul 22, 11:41 AM EDT	Severe Thunderstorm Warning	JAX	Clay, Putnam	35 min
Jul 22, 11:46 AM EDT	Severe Thunderstorm Warning	JAX	Flagler	28 min
Jul 22, 11:54 AM EDT	Special Marine Warning	JAX		30 min
Jul 22, 12:05 PM EDT	Special Weather Statement	JAX	Alachua, Bradford, Union	25 min
Jul 22, 12:12 PM EDT	Severe Thunderstorm Warning	JAX	Columbia, Union	48 min
Jul 22, 12:18 PM EDT	Special Weather Statement	JAX	Saint Johns	42 min
Jul 22, 12:23 PM EDT	Severe Thunderstorm Warning	JAX	Clay, Putnam, Saint Johns	52 min
Jul 22, 12:34 PM EDT	Severe Thunderstorm Warning	JAX	Marion, Putnam	41 min
Jul 22, 12:38 PM EDT	Special Marine Warning	JAX		52 min
Jul 22, 12:41 PM EDT	Special Weather Statement	JAX	Alachua, Bradford	49 min
Jul 22, 12:48 PM EDT	Severe Thunderstorm Warning	JAX	Flagler, Putnam, Saint Johns	42 min
Jul 22, 12:51 PM EDT	Areal Flood Advisory	JAX	Alachua, Bradford, Columbia, Union	3 hr
Jul 22, 12:51 PM EDT	Areal Flood Advisory	JAX	Putnam, Saint Johns	3 hr
Jul 22, 12:58 PM EDT	Severe Thunderstorm Warning	JAX	Alachua, Bradford, Union	47 min
Jul 22, 1:06 PM EDT	Severe Thunderstorm Warning	JAX	Clay	40 min
Jul 22, 1:12 PM EDT	Areal Flood Advisory	JAX	Alachua, Bradford	3 hr
Jul 22, 1:22 PM EDT	Special Weather Statement	JAX	Putnam	53 min
Jul 22, 1:25 PM EDT	Severe Thunderstorm Warning	JAX	Baker, Duval, Nassau	50 min
Jul 22, 1:26 PM EDT	Severe Thunderstorm Warning	JAX	Alachua	34 min
Jul 22, 1:29 PM EDT	Special Weather Statement	JAX	Flagler	46 min
Jul 22, 1:31 PM EDT	Severe Thunderstorm Warning	JAX	Putnam	44 min
Jul 22, 1:33 PM EDT	Special Weather Statement	JAX	Gilchrist	42 min
Jul 22, 1:38 PM EDT	Severe Thunderstorm Warning	JAX	Alachua, Bradford, Columbia, Suwannee, Union	52 min
Jul 22, 1:43 PM EDT	Areal Flood Warning	JAX	Alachua	3 hr
Jul 22, 1:48 PM EDT	Special Weather Statement	JAX	Clay, Saint Johns	42 min
Jul 22, 1:54 PM EDT	Areal Flood Warning	JAX	Alachua, Columbia, Suwannee, Union	3 hr
Jul 22, 2:01 PM EDT	Special Weather Statement	JAX	Alachua	29 min
Jul 22, 2:04 PM EDT	Severe Thunderstorm Warning	JAX	Duval, Nassau	41 min
Jul 22, 2:07 PM EDT	Areal Flood Advisory	JAX	Duval, Nassau	113 min
Jul 22, 2:10 PM EDT	Areal Flood Advisory	JAX	Alachua, Clay, Flagler, Marion, Putnam, Saint Johns	2 hr
Jul 22, 2:13 PM EDT	Special Marine Warning	JAX		46 min
Jul 22, 2:15 PM EDT	Areal Flood Warning	JAX	Alachua, Bradford, Union	3 hr
Jul 22, 2:19 PM EDT	Special Weather Statement	JAX	Marion	41 min
Jul 22, 2:20 PM EDT	Special Weather Statement	JAX	Bradford, Union	40 min
Jul 22, 2:23 PM EDT	Areal Flood Warning	JAX	Alachua, Marion, Putnam	3 hr
Jul 22, 2:24 PM EDT	Severe Thunderstorm Warning	JAX	Alachua, Columbia, Gilchrist, Suwannee	51 min
Jul 22, 2:31 PM EDT	Areal Flood Advisory	JAX	Marion	3 hr
Jul 22, 2:32 PM EDT	Severe Thunderstorm Warning	JAX	Baker, Bradford, Columbia, Union	28 min
Jul 22, 2:35 PM EDT	Special Weather Statement	JAX	Alachua	25 min
Jul 22, 2:42 PM EDT	Severe Thunderstorm Warning	JAX	Marion	36 min
Jul 22, 2:45 PM EDT	Areal Flood Advisory	JAX	Bradford, Columbia, Union	2 hr
Jul 22, 2:48 PM EDT	Areal Flood Advisory	JAX	Alachua, Columbia, Gilchrist, Suwannee	117 min
Jul 22, 3:03 PM EDT	Special Weather Statement	JAX	Alachua	27 min
Jul 22, 3:06 PM EDT	Severe Thunderstorm Warning	JAX	Columbia, Union	24 min
Jul 22, 3:09 PM EDT	Flash Flood Warning	JAX	Alachua, Columbia, Union	113 min
Jul 22, 3:12 PM EDT	Severe Thunderstorm Warning	JAX	Suwannee	33 min
Jul 22, 3:16 PM EDT	Special Weather Statement	JAX	Union	44 min
Jul 22, 3:20 PM EDT	Severe Thunderstorm Warning	JAX	Alachua, Columbia, Gilchrist	40 min
Jul 22, 3:21 PM EDT	Areal Flood Warning	JAX	Alachua, Columbia, Gilchrist, Suwannee	3 hr
Jul 22, 3:21 PM EDT	Tornado Warning	JAX	Alachua, Columbia	24 min
Jul 22, 3:38 PM EDT	Areal Flood Warning	JAX	Marion, Putnam	3 hr
Jul 22, 3:41 PM EDT	Areal Flood Warning	JAX	Columbia, Union	61 min
Jul 22, 3:47 PM EDT	Severe Thunderstorm Warning	JAX	Columbia, Suwannee	12 min
Jul 22, 3:52 PM EDT	Special Weather Statement	JAX	Alachua, Marion, Putnam	38 min
Jul 22, 4:02 PM EDT	Special Weather Statement	JAX	Suwannee	43 min
Jul 22, 4:06 PM EDT	Areal Flood Advisory	JAX	Alachua, Marion	114 min
Jul 22, 4:07 PM EDT	Severe Thunderstorm Warning	JAX	Gilchrist, Suwannee	23 min
Jul 22, 4:19 PM EDT	Flash Flood Warning	JAX	Columbia, Gilchrist, Suwannee	74 min
Jul 22, 4:31 PM EDT	Areal Flood Warning	JAX	Marion	119 min
Jul 22, 4:31 PM EDT	Special Weather Statement	JAX	Gilchrist	29 min
Jul 22, 4:38 PM EDT	Areal Flood Warning	JAX	Alachua, Gilchrist	3 hr
Jul 22, 4:43 PM EDT	Special Weather Statement	JAX	Marion	32 min
Jul 22, 5:00 PM EDT	Areal Flood Warning	JAX	Marion	2 hr
Jul 22, 5:01 PM EDT	Severe Thunderstorm Warning	JAX	Suwannee	29 min
Jul 22, 5:15 PM EDT	Areal Flood Warning	JAX	Alachua, Marion	83 min
Jul 22, 5:17 PM EDT	Special Weather Statement	JAX	Marion	28 min
Jul 22, 5:47 PM EDT	Special Weather Statement	JAX	Suwannee	28 min
Jul 22, 6:05 PM EDT	Special Weather Statement	JAX	Gilchrist	40 min
Jul 22, 6:07 PM EDT	Special Weather Statement	JAX	Hamilton	38 min
Jul 22, 6:14 PM EDT	River Flood Warning	JAX	Alachua, Union	16 days
Jul 22, 6:14 PM EDT	River Flood Warning	JAX	Alachua, Columbia	20 days
Jul 22, 6:20 PM EDT	Special Weather Statement	JAX	Marion	40 min
Jul 22, 6:31 PM EDT	Special Weather Statement	JAX	Suwannee	44 min
Jul 22, 6:47 PM EDT	Special Weather Statement	JAX	Gilchrist	43 min
Jul 22, 6:54 PM EDT	Special Weather Statement	JAX	Marion	51 min
Jul 22, 6:58 PM EDT	Severe Thunderstorm Warning	JAX	Columbia, Hamilton, Suwannee	36 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.