Alert archive / Florida / Tornado Warnings in 2017

Tornado Warning 13, NWS Tampa Bay, FL

September 10, 2017Polk County, Florida

NWS Tampa Bay, FL issued this tornado warning at Sep 10, 2017, 7:57 AM EDT for Polk County, Florida. It was in force for 13 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: Sep 10, 2017, 7:57 AM EDT (11:57 UTC)
Expired: Sep 10, 2017, 8:10 AM EDT
In force: 13 min
Issued by: NWS Tampa Bay, FL
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Polk County, FL

The radar

The Tampa radar (KTBW), 64 km from the middle of the area, began a volume at 11:58 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
Sep 9, 11:45 PM EDT	Tornado Watch	SPC	12 hr

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 00:00Z, 12.0 hours before the alert went out and 64 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: 217 J/kg
Mixed-layer CIN: -116 J/kg
Mixed-layer LCL: 958 m above ground
0-6 km bulk shear: 7 kt
0-1 km storm-relative helicity: -45 m²/s²
0-3 km storm-relative helicity: 64 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

338 
WFUS52 KTBW 101157
TORTBW
FLC105-101230-
/O.NEW.KTBW.TO.W.0013.170910T1157Z-170910T1230Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Tampa Bay Area Ruskin FL
757 AM EDT SUN SEP 10 2017

The National Weather Service in Ruskin has issued a

* Tornado Warning for...
  Southwestern Polk County in central Florida...

* Until 830 AM EDT
    
* At 756 AM EDT, a severe thunderstorm capable of producing a tornado
  was located 8 miles southeast of Bartow, moving west at 30 mph.

  HAZARD...Tornado. 

  SOURCE...Radar indicated rotation. 

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely. 

* This tornadic thunderstorm will remain over mainly rural areas of
  southwestern Polk County, including the following locations: Fort
  Meade, Homeland and Alturas.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to an interior room on the lowest floor of a
sturdy building. Avoid windows. If you are outdoors, in a mobile
home, or in a vehicle, move to the closest substantial shelter and
protect yourself from flying debris.

&&

LAT...LON 2788 8169 2780 8166 2772 8188 2788 8191
TIME...MOT...LOC 1156Z 080DEG 28KT 2783 8174 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

TBW

1 follow-up statement

773 
WWUS52 KTBW 101210
SVSTBW

Severe Weather Statement
National Weather Service Tampa Bay Area Ruskin FL
810 AM EDT SUN SEP 10 2017

FLC105-101220-
/O.CAN.KTBW.TO.W.0013.000000T0000Z-170910T1230Z/
Polk FL-
810 AM EDT SUN SEP 10 2017

...THE TORNADO WARNING FOR SOUTHWESTERN POLK COUNTY IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore the warning has been cancelled.  However gusty winds are
still possible with this thunderstorm.

LAT...LON 2788 8169 2780 8166 2772 8188 2788 8191
TIME...MOT...LOC 1208Z 080DEG 28KT 2781 8186 

$$

TBW

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 10, 1:58 AM EDT	Areal Flood Warning	TBW	Lee	6 hr
Sep 10, 8:56 AM EDT	Tornado Warning	TBW	Hardee	19 min
Sep 10, 10:45 AM EDT	River Flood Warning	TBW	Manatee	35 hr
Sep 10, 10:45 AM EDT	Tornado Warning	TBW	Polk	30 min
Sep 10, 11:08 AM EDT	Tornado Warning	TBW	Hillsborough, Pasco, Polk, Sumter	22 min
Sep 10, 4:05 PM EDT	Extreme Wind Warning	TBW	Lee	115 min

Nearby

Tornado Warnings in Florida, 2017 Every tornado warning in 2017 Tornadoes in 2017

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.