Alert archive / Florida / Tornado Warnings in 2017

Tornado Warning 1, NWS Key West, FL

September 9, 2017Monroe County, Florida

NWS Key West, FL issued this tornado warning at Sep 9, 2017, 5:34 PM EDT for Monroe County, Florida. It was in force for 26 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 9, 2017, 5:34 PM EDT (21:34 UTC)
Expired: Sep 9, 2017, 6:00 PM EDT
In force: 26 min
Issued by: NWS Key West, FL
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.0 in

County Monroe County, FL

The radar

The Key West radar (KBYX), 16 km from the middle of the area, began a volume at 21:36 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, 12:09 PM EDT	Tornado Watch	SPC	12 hr

The nearest sounding before it

Key West, FL (KEYW), launched 12:00Z, 9.6 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: 429 J/kg
Mixed-layer CIN: -63 J/kg
Mixed-layer LCL: 1024 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 41 m²/s²
0-3 km storm-relative helicity: 54 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

As transmitted.

489 
WFUS52 KKEY 092134
TORKEY
FLC087-092200-
/O.NEW.KKEY.TO.W.0001.170909T2134Z-170909T2200Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Key West FL
534 PM EDT SAT SEP 9 2017

The National Weather Service in Key West has issued a

* Tornado Warning for...
  Lower Keys in Monroe County in Florida...

* Until 600 PM EDT
    
* At 533 PM EDT, a severe thunderstorm capable of producing a tornado
  was located 7 miles north of Ohio Key, or 7 miles northwest of West
  End Of Seven Mile Bridge, moving southwest at 70 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. 

* Locations impacted include...
  Key West, Boca Chica, Big Coppitt Key, Boca Chica Channel Bridge,
  Niles Channel Bridge, Spanish Harbor Channel Bridge, Saddlebunch
  Keys, Geiger Key, Sunset Key and Shark Key.

This includes US 1 between mile markers 0 and 35. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or 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 2452 8182 2454 8185 2459 8188 2458 8184
      2466 8180 2472 8166 2470 8162 2474 8161
      2482 8143 2479 8135 2481 8128 2477 8125
      2470 8127 2470 8122 2460 8139 2461 8143
      2458 8146 2460 8151 2452 8174
TIME...MOT...LOC 2133Z 060DEG 59KT 2478 8129 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

MCLOVIN

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 9, 12:02 AM EDT	Special Weather Statement	KEY		58 min
Sep 9, 1:06 AM EDT	Special Weather Statement	KEY		54 min
Sep 9, 7:50 AM EDT	Special Weather Statement	KEY		85 min
Sep 9, 2:46 PM EDT	Special Weather Statement	KEY		59 min
Sep 9, 5:56 PM EDT	Tornado Warning	KEY	Monroe	49 min
Sep 9, 7:07 PM EDT	Tornado Warning	KEY	Monroe	23 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.