Alert archive / Florida / Tornado Watches in 2021
Tornado Watch 341
The Storm Prediction Center issued this tornado watch at Jul 7, 2021, 6:46 AM EDT for 10 counties in Florida; 9 counties in Georgia. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 7, 2021, 6:46 AM EDT (10:46 UTC)
- Expired
- Jul 7, 2021, 1:00 PM EDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Strongest gust expected
- 50 kt
Counties Baker County, FL, Bradford County, FL, Clay County, FL, Columbia County, FL, Duval County, FL, Hamilton County, FL, Nassau County, FL, Saint Johns County, FL, Suwannee County, FL, Union County, FL, Brantley County, GA, Camden County, GA, Charlton County, GA, Clinch County, GA, Echols County, GA, Glynn County, GA, Pierce County, GA, Ware County, GA, Wayne County, GA
The radar
The Jacksonville radar (KJAX), 71 km from the middle of the area, began a volume at 10:47 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 30%
- One or more EF2 to EF5 tornadoes
- 10%
- Ten or more severe wind reports
- 5%
- One or more gusts of 65 knots or more
- 5%
- Ten or more severe hail reports
- 5%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 20%
Warnings issued inside it
3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 7, 7:02 AM EDT | Tornado Warning | JAX | Columbia, Suwannee | 28 min |
| Jul 7, 8:39 AM EDT | Tornado Warning | JAX | Baker, Columbia | 11 min |
| Jul 7, 9:37 AM EDT | Tornado Warning | JAX | Brantley, Pierce, Ware | 23 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Jacksonville, FL (KJAX), launched 00:00Z, 10.8 hours before the alert went out and 71 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.
- Mixed-layer CAPE
- 1886 J/kg
- Mixed-layer CIN
- -3 J/kg
- Mixed-layer LCL
- 813 m above ground
- 0-6 km bulk shear
- 3 kt
- 0-1 km storm-relative helicity
- -31 m²/s²
- 0-3 km storm-relative helicity
- -27 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
113 WWUS20 KWNS 071044 SEL1 SPC WW 071044 FLZ000-GAZ000-071700- URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 341 NWS Storm Prediction Center Norman OK 645 AM EDT Wed Jul 7 2021 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of North Florida Southeast Georgia * Effective this Wednesday morning and afternoon from 645 AM until 100 PM EDT. * Primary threats include... A couple tornadoes possible SUMMARY...Arc of lower-topped showers should spread north from north Florida across southeast Georgia. Environment remains conducive for low-level circulations that might produce a couple brief tornadoes through about midday. The tornado watch area is approximately along and 60 statute miles east and west of a line from 60 miles southwest of Jacksonville FL to 25 miles east northeast of Waycross GA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU1). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && OTHER WATCH INFORMATION...CONTINUE...WW 340... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 0 inches. Extreme turbulence and surface wind gusts to 50 knots. A few cumulonimbi with maximum tops to 400. Mean storm motion vector 15030. ...Grams
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 6, 10:37 PM EDT | Tornado Watch | SPC | Alachua, Charlotte, Citrus, Collier, DeSoto, Gilchrist and 22 more | 9 hr |
| Jul 6, 11:59 PM EDT | Mesoscale Discussion | SPC | Charlotte, DeSoto, Hardee, Hillsborough | 2 hr |
| Jul 7, 3:03 AM EDT | Mesoscale Discussion | SPC | Charlotte, Citrus, DeSoto, Hardee, Hernando, Hillsborough and 5 more | 117 min |
| Jul 7, 5:42 AM EDT | Mesoscale Discussion | SPC | Alachua, Bradford, Charlotte, Citrus, Columbia, DeSoto and 19 more | 2 hr |
| Jul 7, 7:06 AM EDT | Mesoscale Discussion | SPC | Charlotte, Citrus, DeSoto, Hardee, Hernando, Highlands and 10 more | 54 min |
| Jul 7, 10:30 AM EDT | Mesoscale Discussion | SPC | Baker, Bradford, Clay, Columbia, Duval, Hamilton and 3 more | 2 hr |
| Jul 7, 12:28 PM EDT | Mesoscale Discussion | SPC | Baker, Bradford, Clay, Columbia, Duval, Nassau and 1 more | 2 hr |
| Jul 7, 1:04 PM EDT | Tornado Watch | SPC | Baker, Bradford, Clay, Columbia, Duval, Hamilton and 3 more | 7 hr |
| Jul 7, 4:47 PM EDT | Mesoscale Discussion | SPC | Baker, Clay, Columbia, Duval, Nassau, Saint Johns and 1 more | 118 min |
| Jul 7, 6:12 PM EDT | Mesoscale Discussion | SPC | Brantley, Bryan, Camden, Chatham, Effingham, Evans and 6 more | 2 hr |
| Jul 7, 7:25 PM EDT | Tornado Watch | SPC | Bryan, Bulloch, Burke, Candler, Chatham, Effingham and 11 more | 11 hr |
Nearby
Tornado Watches in Florida, 2021Tornado Watches in Georgia, 2021Every tornado watch in 2021
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.