Alert archive / Florida / Special Weather Statements in 2021

Special Weather Statement, NWS Miami, FL

August 31, 2021Monroe County, Florida

NWS Miami, FL issued this special weather statement at Aug 31, 2021, 2:48 PM EDT for Monroe County, Florida. It was in force for 42 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 31, 2021, 2:48 PM EDT (18:48 UTC)
Expired: Aug 31, 2021, 3:30 PM EDT
In force: 42 min
Issued by: NWS Miami, FL
Hail: 0.25 in
Wind: 40

County Monroe County, FL

The radar

The Miami radar (KAMX), 80 km from the middle of the area, began a volume at 18:52 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

Miami, FL (KMFL), launched 12:00Z, 6.8 hours before the alert went out and 82 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: 1240 J/kg
Mixed-layer CIN: -28 J/kg
Mixed-layer LCL: 900 m above ground
0-6 km bulk shear: 2 kt
0-1 km storm-relative helicity: 10 m²/s²
0-3 km storm-relative helicity: 45 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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What forecasters said that day

The local office's own words before this special weather statement went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Miami, FL wrote its last area forecast discussion before this special weather statement went out at Aug 31, 2:01 PM EDT, 47 minutes earlier.

Area forecast discussion, Aug 31, 2:01 PM EDT, 47 minutes before

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      <h1 id="headline">This service is currently unavailable.</h1>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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Hazardous weather outlook, Aug 31, 10:17 AM EDT, 4 hours 31 minutes before

Hazardous Weather Outlook for South Florida...UPDATED
National Weather Service Miami FL
1017 AM EDT Tue Aug 31 2021

AMZ610-630-650-651-670-671-FLZ063-066>075-168-172>174-GMZ656-657-676-
010200-
Lake Okeechobee-Biscayne Bay-
Coastal waters from Jupiter Inlet to Deerfield Beach FL out 20 NM-
Coastal waters from Deerfield Beach to Ocean Reef FL out 20 NM-
Waters from Jupiter Inlet to Deerfield Beach FL from 20 to 60 NM-
Waters from Deerfield Beach to Ocean Reef FL from 20 to 60 NM
excluding the territorial waters of Bahamas-Glades-Hendry-
Inland Palm Beach-Metro Palm Beach-Coastal Collier-Inland Collier-
Inland Broward-Metro Broward-Inland Miami-Dade-Metro Miami-Dade-
Mainland Monroe-Coastal Palm Beach-Coastal Broward-Coastal Miami-
Dade-Far South Miami-Dade-
Coastal waters from Chokoloskee to Bonita Beach FL out 20 NM-
Coastal waters from East Cape Sable to Chokoloskee FL out 20 NM-
Waters from Chokoloskee to Bonita Beach FL from 20 to 60 NM-
1017 AM EDT Tue Aug 31 2021

...A Few Strong Storms With An Isolated Severe Storm Possible
Late This Afternoon Into Early This Evening Eastern Areas...

This hazardous weather outlook is for South Florida.

.DAY ONE...TODAY AND TONIGHT

Thunderstorms: Isolated thunderstorms possible west coast areas late
this morning into early this afternoon before shifting into the
interior and east coast metro areas with increasing coverage to
scattered to numerous. A few storms could become strong with a
possible severe storm over the interior and east coast metro areas
late this afternoon into early this evening.

Wind: The strongest thunderstorms could contain wind gusts in excess
of 50 mph late this afternoon into early this evening.

Flooding: Localized flooding possible over the east and west coast
metro areas with strongest storms.

Tornadoes: The strongest storms could produce an isolated weak
tornado.

Waterspouts: Waterspouts will be possible with the showers and
thunderstorms over the local South Florida waters.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

Scattered showers and thunderstorms will continue through the rest
of the forecast period, with locally gusty winds, frequent
lightning, and heavy rainfall possible.

.SPOTTER INFORMATION STATEMENT...

Widespread spotter activation is not anticipated, however individual
spotters are encouraged to report high wind, hail and flooding to
the National Weather Service forecast office in Miami.

For more information...visit the National Weather Service in Miami
website at www.weather.gov/miami.

Baxter

In the hours before

Special weather statement, Aug 31, 2:48 PM EDT, 0 minutes before

Special Weather Statement
National Weather Service Miami FL
248 PM EDT Tue Aug 31 2021

FLZ069-070-075-311930-
Coastal Collier County FL-Inland Collier County FL-
Mainland Monroe FL-
248 PM EDT Tue Aug 31 2021

...A strong thunderstorm will impact portions of southeastern Collier
and north central Mainland Monroe Counties through 330 PM EDT...

At 248 PM EDT, National Weather Service meteorologists were tracking
a strong thunderstorm near Big Cypress National Preserve, or 16 miles
northeast of Everglades City, moving east at 20 mph.

HAZARD...Winds in excess of 40 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Big Cypress National Preserve.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These winds can down small tree limbs and branches, and blow around
unsecured small objects. Seek shelter in a safe building until the
storm passes.

&&

LAT...LON 2610 8122 2604 8087 2602 8087 2572 8106
      2594 8131
TIME...MOT...LOC 1848Z 289DEG 18KT 2598 8115

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

SPM

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 30, 8:15 PM EDT	Special Weather Statement	MFL	Glades	45 min
Aug 31, 3:22 PM EDT	Special Weather Statement	MFL	Miami-Dade	38 min
Aug 31, 3:41 PM EDT	Special Weather Statement	MFL	Broward	49 min
Aug 31, 4:01 PM EDT	Special Marine Warning	MFL		44 min
Aug 31, 4:22 PM EDT	Special Weather Statement	MFL	Miami-Dade	38 min
Aug 31, 4:40 PM EDT	Special Weather Statement	MFL	Miami-Dade	50 min
Aug 31, 4:52 PM EDT	Special Weather Statement	MFL	Broward	23 min
Aug 31, 5:11 PM EDT	Special Marine Warning	MFL		34 min
Aug 31, 5:36 PM EDT	Special Weather Statement	MFL	Broward	39 min
Aug 31, 6:05 PM EDT	Special Weather Statement	MFL	Miami-Dade	40 min

Nearby

Special Weather Statements in Florida, 2021 Every special weather statement 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.