Alert archive / Florida / Special Weather Statements in 2021

Special Weather Statement, NWS Melbourne, FL

August 20, 2021Volusia County, Florida

NWS Melbourne, FL issued this special weather statement at Aug 20, 2021, 2:21 PM EDT for Volusia County, Florida. It was in force for 39 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 20, 2021, 2:21 PM EDT (18:21 UTC)
Expired
Aug 20, 2021, 3:00 PM EDT
In force
39 min
Issued by
NWS Melbourne, FL
Hail
0.00 in
Wind
50

County Volusia County, FL

The radar

The Melbourne radar (KMLB), 111 km from the middle of the area, began a volume at 18:25 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

Cape Canaveral, FL (KXMR), launched 12:00Z, 6.4 hours before the alert went out and 87 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, Cape Canaveral, FL at 12:00Z on 2021-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 359 joules per kilogram.LCLLFCEL10008507005003002001001 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, Cape Canaveral, FL at 12:00Z on 2021-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 46 square meters per square second.1939Sfc1 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
359 J/kg
Mixed-layer CIN
-95 J/kg
Mixed-layer LCL
1120 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
46 m²/s²
0-3 km storm-relative helicity
82 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

458 
WWUS82 KMLB 201821
SPSMLB

Special Weather Statement
National Weather Service Melbourne FL
221 PM EDT Fri Aug 20 2021
 
FLZ041-141-201900-
Coastal Volusia FL-Inland Volusia FL-
221 PM EDT Fri Aug 20 2021

...A strong thunderstorm will impact portions of central Volusia
County through 300 PM EDT...

At 220 PM EDT, Doppler radar was tracking a strong thunderstorm 8
miles southwest of Daytona Beach Airport, or 9 miles southwest of
Port Orange, moving south at 15 mph.

HAZARD...Wind gusts up to 45 to 50 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around 
         unsecured objects.

Locations impacted include...
Deltona, Port Orange, New Smyrna Beach, Samsula-Spruce Creek and
Spruce Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. Torrential 
rainfall is also occurring with this storm and may lead to localized 
flooding. Do not drive your vehicle through flooded roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 2912 8122 2914 8104 2888 8096 2885 8120
TIME...MOT...LOC 1820Z 350DEG 13KT 2907 8111 

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

$$

Weitlich

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 20, 3:27 AM EDTRip Current StatementMLBVolusia24 hr
Aug 20, 5:03 AM EDTRip Current StatementMLBVolusia39 hr
Aug 20, 3:18 PM EDTSpecial Weather StatementMLBSeminole42 min
Aug 20, 3:49 PM EDTSpecial Weather StatementMLBSeminole41 min
Aug 20, 4:31 PM EDTSpecial Weather StatementMLBOsceola44 min
Aug 20, 4:59 PM EDTSpecial Weather StatementMLBOrange31 min
Aug 20, 5:33 PM EDTSpecial Weather StatementMLBOsceola27 min

Nearby

Special Weather Statements in Florida, 2021Every 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.