Alert archive / Florida / Mesoscale Discussions in 2012

Mesoscale Discussion 1819

August 27, 201219 counties in Florida

The Storm Prediction Center issued this mesoscale discussion at Aug 27, 2012, 7:26 AM EDT for 19 counties in Florida. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: Aug 27, 2012, 7:26 AM EDT (11:26 UTC)
Expired: Aug 27, 2012, 10:30 AM EDT
In force: 3 hr
Issued by: the Storm Prediction Center

Counties Brevard County, FL, Citrus County, FL, Dixie County, FL, Gilchrist County, FL, Hernando County, FL, Indian River County, FL, Lake County, FL, Levy County, FL, Marion County, FL, Okeechobee County, FL, Orange County, FL, Osceola County, FL, Palm Beach County, FL, Pasco County, FL, Polk County, FL, Saint Lucie County, FL, Seminole County, FL, Sumter County, FL, Volusia County, FL

The radar

The Tampa radar (KTBW), 96 km from the middle of the area, began a volume at 11:27 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

Tampa Bay, FL (KTBW), launched 00:00Z, 11.4 hours before the alert went out and 96 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: 275 J/kg
Mixed-layer CIN: -34 J/kg
Mixed-layer LCL: 782 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 113 m²/s²
0-3 km storm-relative helicity: 163 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.5

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 26, 10:44 PM EDT	Mesoscale Discussion	SPC	Broward, Charlotte, Collier, DeSoto, Glades, Hendry and 4 more	2 hr
Aug 26, 11:24 PM EDT	Tornado Watch	SPC	Brevard, Broward, Charlotte, Collier, DeSoto, Glades and 17 more	12 hr
Aug 27, 3:44 AM EDT	Mesoscale Discussion	SPC	Broward, Charlotte, Collier, DeSoto, Glades, Hardee and 16 more	2 hr
Aug 27, 7:55 AM EDT	Mesoscale Discussion	SPC	Broward, Charlotte, Collier, DeSoto, Glades, Hardee and 16 more	95 min
Aug 27, 11:54 AM EDT	Mesoscale Discussion	SPC	Indian River, Lake, Marion, Orange, Osceola, Saint Lucie and 3 more	2 hr
Aug 27, 2:28 PM EDT	Mesoscale Discussion	SPC	Citrus, DeSoto, Hardee, Hernando, Highlands, Hillsborough and 6 more	92 min

Nearby

Mesoscale Discussions in Florida, 2012 Every mesoscale discussion in 2012

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.