Alert archive / Florida / Special Weather Statements in 2021

Special Weather Statement, NWS Melbourne, FL

April 20, 2021Seminole County, Florida

NWS Melbourne, FL issued this special weather statement at Apr 20, 2021, 8:13 AM EDT for Seminole County, Florida. It was in force for 32 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: Apr 20, 2021, 8:13 AM EDT (12:13 UTC)
Expired: Apr 20, 2021, 8:45 AM EDT
In force: 32 min
Issued by: NWS Melbourne, FL

County Seminole County, FL

The radar

The Melbourne radar (KMLB), 75 km from the middle of the area, began a volume at 12:17 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, 0.2 hours before the alert went out and 51 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: 236 J/kg
Mixed-layer CIN: -45 J/kg
Mixed-layer LCL: 868 m above ground
0-6 km bulk shear: 51 kt
0-1 km storm-relative helicity: 125 m²/s²
0-3 km storm-relative helicity: 270 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 3.0

Open this sounding in Storm Lab

The text

As transmitted.

494 
WWUS82 KMLB 201213
SPSMLB

Special Weather Statement
National Weather Service Melbourne FL
813 AM EDT Tue Apr 20 2021
 
FLZ041-046-141-147-201245-
Coastal Volusia FL-Northern Brevard County FL-Seminole FL-
Inland Volusia FL-
813 AM EDT Tue Apr 20 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN SEMINOLE...
NORTHWESTERN BREVARD AND SOUTHEASTERN VOLUSIA COUNTIES UNTIL 845 AM
EDT...

At 813 AM EDT, Doppler radar was tracking a strong thunderstorm near
Chuluota, moving northeast at 35 mph.

Penny size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Oak Hill, Mims, Scottsmoor, Haulover Canal and Geneva. 

LAT...LON 2894 8081 2870 8064 2861 8102 2861 8107
      2871 8113
TIME...MOT...LOC 1213Z 234DEG 32KT 2868 8105 

$$

Combs

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 20, 7:41 AM EDT	Special Weather Statement	MLB	Orange	34 min
Apr 20, 7:46 AM EDT	Severe Thunderstorm Warning	MLB	Orange, Seminole	29 min
Apr 20, 7:58 AM EDT	Special Weather Statement	MLB	Lake	32 min
Apr 20, 8:22 AM EDT	Special Weather Statement	MLB	Orange	23 min
Apr 20, 8:26 AM EDT	Special Marine Warning	MLB		49 min
Apr 20, 8:48 AM EDT	Special Weather Statement	MLB	Seminole	27 min
Apr 20, 9:08 AM EDT	Special Weather Statement	MLB	Brevard	52 min
Apr 20, 9:26 AM EDT	Special Marine Warning	MLB		64 min
Apr 20, 11:09 AM EDT	Special Weather Statement	MLB	Okeechobee	36 min
Apr 20, 11:47 AM EDT	Special Weather Statement	MLB	Indian River	43 min
Apr 20, 12:28 PM EDT	Special Marine Warning	MLB		3 hr
Apr 20, 1:35 PM EDT	Areal Flood Advisory	MLB	Orange, Osceola	3 hr
Apr 20, 2:00 PM EDT	Special Marine Warning	MLB		3 hr
Apr 20, 2:10 PM EDT	Areal Flood Advisory	MLB	Brevard, Orange	3 hr
Apr 20, 2:14 PM EDT	Special Weather Statement	MLB	Osceola	46 min
Apr 20, 2:53 PM EDT	Special Weather Statement	MLB	Brevard, Osceola	37 min
Apr 20, 4:26 PM EDT	Special Weather Statement	MLB	Osceola	49 min
Apr 20, 4:44 PM EDT	Special Weather Statement	MLB	Indian River	46 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.