Alert archive / Florida / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 2, NWS Key West, FL

August 24, 2020Monroe County, Florida

NWS Key West, FL issued this severe thunderstorm warning at Aug 24, 2020, 3:18 PM EDT for Monroe County, Florida. It was in force for 27 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
Aug 24, 2020, 3:18 PM EDT (19:18 UTC)
Expired
Aug 24, 2020, 3:45 PM EDT
In force
27 min
Issued by
NWS Key West, FL
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Monroe County, FL

The radar

The Key West radar (KBYX), 23 km from the middle of the area, began a volume at 19:16 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 nearest sounding before it

Key West, FL (KEYW), launched 12:00Z, 7.3 hours before the alert went out and 26 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-pSkew-T log-p diagram, Key West, FL at 12:00Z on 2020-08-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1901 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Key West, FL at 12:00Z on 2020-08-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -64 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
1901 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
830 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
-64 m²/s²
0-3 km storm-relative helicity
3 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

713 
WUUS52 KKEY 241918
SVRKEY
FLC087-241945-
/O.NEW.KKEY.SV.W.0002.200824T1918Z-200824T1945Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Key West FL
318 PM EDT Mon Aug 24 2020

The National Weather Service in Key West has issued a

* Severe Thunderstorm Warning for...
  Lower Keys in Monroe County in Florida...
  Middle Keys in Monroe County in Florida...

* Until 345 PM EDT..

* At 317 PM EDT, severe thunderstorms were located along a line
  extending from Sunset Key to near Little Palm Island Resort to 17 
  miles southeast of Boot Key, moving north at 40 mph. A wind gust 
  of 70 mph was observed in Key West.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations in the warning include...
  Key West, Marathon, Bahia Honda Channel Bridge, Seven Mile Bridge,
  East End Of Seven Mile Bridge, Big Coppitt Key, Boca Chica Channel
  Bridge, Niles Channel Bridge, Spanish Harbor Channel Bridge and
  Boca Chica.

This includes US 1 between mile markers 0 and 58. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 2452 8191 2462 8195 2463 8191 2458 8184
      2467 8179 2473 8168 2470 8162 2478 8159
      2483 8148 2481 8128 2469 8128 2469 8120
      2473 8116 2480 8096 2473 8095 2466 8106
      2469 8118 2459 8138 2461 8143 2452 8176
TIME...MOT...LOC 1917Z 164DEG 35KT 2454 8184 2458 8143 2447 8097 

HAIL...<.75IN
WIND...60MPH
 
$$

Haner
1 follow-up statement
979 
WWUS52 KKEY 241949
SVSKEY

Severe Weather Statement
National Weather Service Key West FL
349 PM EDT Mon Aug 24 2020

FLC087-241959-
/O.EXP.KKEY.SV.W.0002.000000T0000Z-200824T1945Z/
Lower Keys in Monroe FL-Middle Keys in Monroe FL-
349 PM EDT Mon Aug 24 2020

...THE SEVERE THUNDERSTORM WARNING FOR LOWER KEYS IN MONROE AND
MIDDLE KEYS IN MONROE COUNTIES HAS EXPIRED...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning has been allowed to expire.

LAT...LON 2452 8191 2462 8195 2463 8191 2458 8184
      2467 8179 2473 8168 2470 8162 2478 8159
      2483 8148 2481 8128 2469 8128 2469 8120
      2473 8116 2480 8096 2473 8095 2466 8106
      2469 8118 2459 8138 2461 8143 2452 8176
TIME...MOT...LOC 1949Z 164DEG 35KT 2483 8193 2487 8152 2476 8106 

$$

Haner

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 23, 11:31 PM EDTGale WarningKEY18 hr
Aug 23, 11:31 PM EDTTropical Storm WarningKEYMonroe35 hr
Aug 24, 5:24 AM EDTWind AdvisoryKEYMonroe12 hr
Aug 24, 3:23 PM EDTSpecial Marine WarningKEY67 min
Aug 24, 4:10 PM EDTCoastal Flood AdvisoryKEYMonroe7 hr
Aug 24, 4:29 PM EDTSpecial Marine WarningKEY45 min
Aug 24, 5:47 PM EDTSmall Craft AdvisoryKEY23 hr

Nearby

Severe Thunderstorm Warnings in Florida, 2020Every severe thunderstorm warning in 2020

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.