Alert archive / Florida / Tornado Watches in 2021

Tornado Watch 6

February 6, 202120 counties in Florida

The Storm Prediction Center issued this tornado watch at Feb 6, 2021, 10:58 PM EST for 20 counties in Florida. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued: Feb 6, 2021, 10:58 PM EST (03:58 UTC)
Expired: Feb 7, 2021, 7:00 AM EST
In force: 8 hr
Issued by: the Storm Prediction Center
Largest hail expected: 1.5 in
Strongest gust expected: 60 kt

Counties Brevard County, FL, Citrus County, FL, Flagler County, FL, Hardee County, FL, Hernando County, FL, Hillsborough County, FL, Lake County, FL, Levy County, FL, Manatee County, FL, Marion County, FL, Orange County, FL, Osceola County, FL, Pasco County, FL, Pinellas County, FL, Polk County, FL, Putnam County, FL, Sarasota County, FL, Seminole County, FL, Sumter County, FL, Volusia County, FL

The radar

The Tampa radar (KTBW), 101 km from the middle of the area, began a volume at 03:59 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: 40%
One or more EF2 to EF5 tornadoes: 30%
Ten or more severe wind reports: 30%
One or more gusts of 65 knots or more: 20%
Ten or more severe hail reports: 20%
One or more hailstones of 2 inches or more: 10%
Six or more combined severe hail and wind reports: 50%

Warnings issued inside it

1 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
Feb 7, 1:09 AM EST	Severe Thunderstorm Warning	JAX	Marion	20 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

Tampa Bay, FL (KTBW), launched 00:00Z, 4.0 hours before the alert went out and 101 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: 1198 J/kg
Mixed-layer CIN: -24 J/kg
Mixed-layer LCL: 813 m above ground
0-6 km bulk shear: 51 kt
0-1 km storm-relative helicity: 249 m²/s²
0-3 km storm-relative helicity: 286 m²/s²
Significant tornado parameter: 1.8
Supercell composite: 7.7

Open this sounding in Storm Lab

The text

As transmitted.

498 
WWUS20 KWNS 070355
SEL6  
SPC WW 070355
FLZ000-CWZ000-071200-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 6
NWS Storm Prediction Center Norman OK
1100 PM EST Sat Feb 6 2021

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  North and central Florida
  Coastal Waters

* Effective this Saturday night and Sunday morning from 1100 PM
  until 700 AM EST.

* Primary threats include...
  A couple intense tornadoes possible
  Isolated damaging wind gusts to 70 mph possible
  Isolated large hail events to 1.5 inches in diameter possible

SUMMARY...Multiple supercells are expected to spread inland from the
northeast Gulf across portions of north and central Florida
overnight. The environment will support a risk of a couple tornadoes
along with isolated damaging winds and marginally severe hail.

The tornado watch area is approximately along and 80 statute miles
north and south of a line from 15 miles west northwest of Saint
Petersburg FL to 25 miles south southeast of Daytona Beach FL. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU6).

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.

&&

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 1.5 inches. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean
storm motion vector 24040.

...Grams

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Feb 6, 7:41 PM EST	Mesoscale Discussion	SPC	Alachua, Bradford, Citrus, Clay, Dixie, Flagler and 11 more	2 hr
Feb 6, 9:48 PM EST	Mesoscale Discussion	SPC	Alachua, Citrus, Flagler, Hernando, Hillsborough, Lake and 10 more	87 min
Feb 7, 2:13 AM EST	Mesoscale Discussion	SPC	Brevard, Citrus, Flagler, Hardee, Hernando, Hillsborough and 14 more	2 hr
Feb 7, 6:28 AM EST	Mesoscale Discussion	SPC	Brevard, Hardee, Hillsborough, Lake, Manatee, Orange and 7 more	2 hr

Nearby

Tornado Watches in Florida, 2021 Every 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.