Alert archive / Florida / Mesoscale Discussions in 2020

Mesoscale Discussion 463

April 23, 202023 counties in Florida; 7 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Apr 23, 2020, 6:09 PM EDT for 23 counties in Florida; 7 counties in Georgia. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued
Apr 23, 2020, 6:09 PM EDT (22:09 UTC)
Expired
Apr 23, 2020, 7:45 PM EDT
In force
96 min
Issued by
the Storm Prediction Center
All 30 counties

Alachua County, FL, Baker County, FL, Bradford County, FL, Calhoun County, FL, Clay County, FL, Columbia County, FL, Dixie County, FL, Duval County, FL, Franklin County, FL, Gadsden County, FL, Gilchrist County, FL, Gulf County, FL, Hamilton County, FL, Jefferson County, FL, Lafayette County, FL, Leon County, FL, Liberty County, FL, Madison County, FL, Saint Johns County, FL, Suwannee County, FL, Taylor County, FL, Union County, FL, Wakulla County, FL, Brooks County, GA, Decatur County, GA, Echols County, GA, Grady County, GA, Lowndes County, GA, Seminole County, GA, Thomas County, GA

The radar

The Tallahassee radar (KTLH), 62 km from the middle of the area, began a volume at 22:11 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Tallahassee Rgnl, FL (KTLH), launched 12:00Z, 10.2 hours before the alert went out and 59 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, Tallahassee Rgnl, FL at 12:00Z on 2020-04-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tallahassee Rgnl, FL at 12:00Z on 2020-04-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 455 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1318 m above ground
0-6 km bulk shear
71 kt
0-1 km storm-relative helicity
455 m²/s²
0-3 km storm-relative helicity
663 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.

IssuedProductOfficeCountiesLasted
Apr 23, 3:28 AM EDTMesoscale DiscussionSPCEscambia, Santa Rosa92 min
Apr 23, 5:05 AM EDTTornado WatchSPCBay, Calhoun, Escambia, Holmes, Jackson, Okaloosa and 3 more11 hr
Apr 23, 8:43 AM EDTMesoscale DiscussionSPCBay, Calhoun, Escambia, Franklin, Gadsden, Gulf and 10 more92 min
Apr 23, 10:29 AM EDTMesoscale DiscussionSPCBaker, Columbia, Gadsden, Hamilton, Jackson, Jefferson and 5 more61 min
Apr 23, 10:52 AM EDTTornado WatchSPCFranklin, Gadsden, Gulf, Hamilton, Jefferson, Leon and 4 more6 hr
Apr 23, 1:05 PM EDTMesoscale DiscussionSPCBay, Escambia, Okaloosa, Santa Rosa, Walton, Washington55 min
Apr 23, 3:28 PM EDTMesoscale DiscussionSPCBay, Calhoun, Franklin, Gulf, Jefferson, Leon and 6 more62 min
Apr 23, 3:47 PM EDTTornado WatchSPCBay, Calhoun, Dixie, Franklin, Gadsden, Gulf and 11 more6 hr
Apr 23, 6:52 PM EDTTornado WatchSPCAlachua, Baker, Bradford, Clay, Columbia, Duval and 7 more5 hr
Apr 23, 1:25 PM EDTMesoscale DiscussionSPCAtkinson, Brantley, Clinch, Echols, Lanier, Lowndes and 3 more95 min
Apr 23, 2:22 PM EDTMesoscale DiscussionSPCChatham, Effingham, Screven83 min

Nearby

Mesoscale Discussions in Florida, 2020Mesoscale Discussions in Georgia, 2020Every 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.