Alert archive / Florida / Tornado Watches in 2021
Tornado Watch 545
The Storm Prediction Center issued this tornado watch at Oct 28, 2021, 9:00 AM EDT for 41 counties in Florida. It was in force for 10 hr.
The area
The outline as issued.
The facts
- Issued
- Oct 28, 2021, 9:00 AM EDT (13:00 UTC)
- Expired
- Oct 28, 2021, 7:00 PM EDT
- In force
- 10 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1 in
- Strongest gust expected
- 60 kt
All 41 counties
Alachua County, FL, Baker County, FL, Bradford County, FL, Brevard County, FL, Charlotte County, FL, Citrus County, FL, Clay County, FL, Columbia County, FL, DeSoto County, FL, Dixie County, FL, Duval County, FL, Flagler County, FL, Gilchrist County, FL, Hamilton County, FL, Hardee County, FL, Hernando County, FL, Highlands County, FL, Hillsborough County, FL, Indian River County, FL, Lafayette County, FL, Lake County, FL, Lee County, FL, Levy County, FL, Manatee County, FL, Marion County, FL, Nassau County, FL, Okeechobee County, FL, Orange County, FL, Osceola County, FL, Pasco County, FL, Pinellas County, FL, Polk County, FL, Putnam County, FL, Saint Johns County, FL, Sarasota County, FL, Seminole County, FL, Sumter County, FL, Suwannee County, FL, Taylor County, FL, Union County, FL, Volusia County, FL
The radar
The Tampa radar (KTBW), 128 km from the middle of the area, began a volume at 12:59 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
- 50%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 40%
- One or more gusts of 65 knots or more
- 10%
- 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
- 60%
Warnings issued inside it
19 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 28, 12:06 PM EDT | Severe Thunderstorm Warning | JAX | Alachua, Marion, Putnam | 39 min |
| Oct 28, 12:10 PM EDT | Severe Thunderstorm Warning | JAX | Marion | 50 min |
| Oct 28, 12:33 PM EDT | Severe Thunderstorm Warning | JAX | Clay, Flagler, Putnam, Saint Johns | 57 min |
| Oct 28, 12:45 PM EDT | Severe Thunderstorm Warning | JAX | Marion | 45 min |
| Oct 28, 1:00 PM EDT | Severe Thunderstorm Warning | TBW | Hillsborough, Pasco, Pinellas, Polk | 45 min |
| Oct 28, 1:16 PM EDT | Tornado Warning | TBW | Hillsborough, Pinellas | 13 min |
| Oct 28, 1:19 PM EDT | Tornado Warning | TBW | Manatee, Sarasota | 26 min |
| Oct 28, 1:25 PM EDT | Severe Thunderstorm Warning | JAX | Flagler, Marion, Putnam, Saint Johns | 65 min |
| Oct 28, 1:38 PM EDT | Severe Thunderstorm Warning | MLB | Lake, Orange | 52 min |
| Oct 28, 1:52 PM EDT | Tornado Warning | TBW | Hardee, Manatee, Sarasota | 23 min |
| Oct 28, 2:14 PM EDT | Tornado Warning | TBW | Manatee | 16 min |
| Oct 28, 2:19 PM EDT | Severe Thunderstorm Warning | MLB | Lake, Orange, Seminole | 41 min |
| Oct 28, 2:27 PM EDT | Tornado Warning | TBW | Hardee, Manatee | 18 min |
| Oct 28, 2:54 PM EDT | Tornado Warning | TBW | Manatee, Sarasota | 21 min |
| Oct 28, 2:57 PM EDT | Tornado Warning | TBW | DeSoto | 18 min |
| Oct 28, 3:11 PM EDT | Tornado Warning | TBW | DeSoto, Hardee | 19 min |
| Oct 28, 3:29 PM EDT | Tornado Warning | MLB | Volusia | 16 min |
| Oct 28, 4:59 PM EDT | Tornado Warning | MLB | Indian River, Osceola | 31 min |
| Oct 28, 5:21 PM EDT | Tornado Warning | MLB | Brevard, Indian River | 24 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 12:00Z, 1.0 hours before the alert went out and 128 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
- 1406 J/kg
- Mixed-layer CIN
- -14 J/kg
- Mixed-layer LCL
- 675 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 211 m²/s²
- 0-3 km storm-relative helicity
- 236 m²/s²
- Significant tornado parameter
- 1.5
- Supercell composite
- 10.9
The text
As transmitted.
566 WWUS20 KWNS 281257 SEL5 SPC WW 281257 FLZ000-CWZ000-282100- URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 545 NWS Storm Prediction Center Norman OK 900 AM EDT Thu Oct 28 2021 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Florida Coastal Waters * Effective this Thursday morning and afternoon from 900 AM until 500 PM EDT. * Primary threats include... A few tornadoes possible Scattered damaging wind gusts to 70 mph possible SUMMARY...Severe thunderstorms including the potential for wind damage and a few tornadoes will increase through late morning/afternoon especially across the northern/western Florida Peninsula as the air mass destabilizes and deep-layer/low-level winds strengthen. The tornado watch area is approximately along and 65 statute miles east and west of a line from 55 miles north northwest of Gainesville FL to 15 miles west southwest of Fort Myers FL. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU5). 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 inch. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 22040. ...Guyer
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 27, 8:21 PM EDT | Tornado Watch | SPC | Escambia, Okaloosa, Santa Rosa | 7 hr |
| Oct 27, 10:08 PM EDT | Mesoscale Discussion | SPC | Escambia, Okaloosa, Santa Rosa | 97 min |
| Oct 27, 11:22 PM EDT | Mesoscale Discussion | SPC | Bay, Franklin, Gulf, Walton | 2 hr |
| Oct 28, 12:21 AM EDT | Tornado Watch | SPC | Bay, Calhoun, Franklin, Gulf, Liberty, Wakulla and 2 more | 6 hr |
| Oct 28, 8:12 AM EDT | Mesoscale Discussion | SPC | Alachua, Bradford, Citrus, Dixie, Gilchrist, Hernando and 7 more | 2 hr |
| Oct 28, 11:51 AM EDT | Mesoscale Discussion | SPC | Charlotte, DeSoto, Flagler, Hardee, Highlands, Hillsborough and 11 more | 114 min |
| Oct 28, 2:08 PM EDT | Mesoscale Discussion | SPC | Charlotte, DeSoto, Flagler, Hardee, Lake, Manatee and 3 more | 97 min |
| Oct 28, 4:11 PM EDT | Mesoscale Discussion | SPC | Brevard, Charlotte, DeSoto, Glades, Highlands, Indian River and 2 more | 94 min |
Nearby
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.