Alert archive / Florida / Mesoscale Discussions in 2020

Mesoscale Discussion 871

June 7, 202018 counties in Florida

The Storm Prediction Center issued this mesoscale discussion at Jun 7, 2020, 3:41 PM EDT for 18 counties in Florida. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Jun 7, 2020, 3:41 PM EDT (19:41 UTC)
Expired: Jun 7, 2020, 5:45 PM EDT
In force: 2 hr
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch unlikely
Chance of a watch: 20%

Counties Alachua County, FL, Baker County, FL, Bradford County, FL, Clay County, FL, Columbia County, FL, Dixie County, FL, Gilchrist County, FL, Jefferson County, FL, Lafayette County, FL, Lake County, FL, Levy County, FL, Madison County, FL, Marion County, FL, Putnam County, FL, Sumter County, FL, Suwannee County, FL, Taylor County, FL, Union County, FL

The radar

The Jacksonville radar (KJAX), 135 km from the middle of the area, began a volume at 19:43 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

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 7.7 hours before the alert went out and 189 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: 13 J/kg
Mixed-layer CIN: -142 J/kg
Mixed-layer LCL: 795 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 187 m²/s²
0-3 km storm-relative helicity: 306 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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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 6, 9:38 PM EDT	Mesoscale Discussion	SPC	Bradford, Clay, Duval, Flagler, Marion, Orange and 4 more	2 hr
Jun 7, 12:40 AM EDT	Mesoscale Discussion	SPC	Charlotte, Citrus, DeSoto, Dixie, Franklin, Gilchrist and 14 more	2 hr
Jun 7, 7:12 AM EDT	Mesoscale Discussion	SPC	Bay, Calhoun, Escambia, Franklin, Gadsden, Gulf and 6 more	2 hr

Nearby

Mesoscale Discussions in Florida, 2020 Every mesoscale discussion in 2020

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.