Alert archive / Florida / Mesoscale Discussions in 2024

Mesoscale Discussion 1815

August 4, 202442 counties in Florida; Charlton County, Echols County, Georgia

The Storm Prediction Center issued this mesoscale discussion at Aug 4, 2024, 1:47 PM EDT for 42 counties in Florida; Charlton County, Echols County, Georgia. It was in force for 118 min.

The area

The outline as issued.

The facts

Issued: Aug 4, 2024, 1:47 PM EDT (17:47 UTC)
Expired: Aug 4, 2024, 3:45 PM EDT
In force: 118 min
Issued by: the Storm Prediction Center
Concerning: Tornado watch 594

All 44 counties

Alachua County, FL, Baker County, FL, Bradford County, FL, Brevard County, FL, Charlotte County, FL, Citrus County, FL, Clay County, FL, Columbia County, FL, DeSoto County, FL, Dixie County, FL, Duval County, FL, Flagler County, FL, Gilchrist County, FL, Glades County, FL, Hamilton County, FL, Hardee County, FL, Hendry County, FL, Hernando County, FL, Highlands County, FL, Hillsborough County, FL, Jefferson County, FL, Lafayette County, FL, Lake County, FL, Lee County, FL, Levy County, FL, Madison County, FL, Manatee County, FL, Marion County, FL, Nassau County, FL, Okeechobee County, FL, Orange County, FL, Osceola County, FL, Pasco County, FL, Polk County, FL, Putnam County, FL, Saint Johns County, FL, Seminole County, FL, Sumter County, FL, Suwannee County, FL, Taylor County, FL, Union County, FL, Volusia County, FL, Charlton County, GA, Echols County, GA

The radar

The Tampa radar (KTBW), 102 km from the middle of the area, began a volume at 17:47 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 12:00Z, 5.8 hours before the alert went out and 102 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: 374 J/kg
Mixed-layer CIN: -44 J/kg
Mixed-layer LCL: 679 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 362 m²/s²
0-3 km storm-relative helicity: 327 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 6.1

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 4, 7:47 AM EDT	Mesoscale Discussion	SPC	Charlotte, DeSoto, Hillsborough, Lee, Manatee, Pinellas and 1 more	88 min
Aug 4, 10:32 AM EDT	Mesoscale Discussion	SPC	Alachua, Bradford, Charlotte, Citrus, Collier, Columbia and 27 more	88 min
Aug 4, 10:57 AM EDT	Tornado Watch	SPC	Alachua, Baker, Bradford, Charlotte, Citrus, Clay and 40 more	9 hr
Aug 4, 4:53 PM EDT	Mesoscale Discussion	SPC	Alachua, Baker, Bradford, Charlotte, Citrus, Clay and 35 more	2 hr
Aug 4, 7:05 PM EDT	Mesoscale Discussion	SPC	Alachua, Baker, Bradford, Brevard, Charlotte, Citrus and 39 more	55 min
Aug 4, 7:57 PM EDT	Tornado Watch	SPC	Alachua, Baker, Bradford, Brevard, Citrus, Clay and 31 more	10 hr

Nearby

Mesoscale Discussions in Florida, 2024 Mesoscale Discussions in Georgia, 2024 Every mesoscale discussion in 2024

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.