Alert archive / Georgia / Mesoscale Discussions in 2020

Mesoscale Discussion 457

April 23, 2020Houston County, Alabama; 11 counties in Florida; 45 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Apr 23, 2020, 9:29 AM CDT for Houston County, Alabama; 11 counties in Florida; 45 counties in Georgia. It was in force for 61 min.

The area

The outline as issued.

The facts

Issued
Apr 23, 2020, 9:29 AM CDT (14:29 UTC)
Expired
Apr 23, 2020, 10:30 AM CDT
In force
61 min
Issued by
the Storm Prediction Center
Chance of a watch
80%
All 57 counties

Houston County, AL, Baker County, FL, Columbia County, FL, Gadsden County, FL, Hamilton County, FL, Jackson County, FL, Jefferson County, FL, Leon County, FL, Madison County, FL, Nassau County, FL, Suwannee County, FL, Union County, FL, Appling County, GA, Atkinson County, GA, Bacon County, GA, Baker County, GA, Ben Hill County, GA, Berrien County, GA, Brantley County, GA, Brooks County, GA, Camden County, GA, Charlton County, GA, Clinch County, GA, Coffee County, GA, Colquitt County, GA, Cook County, GA, Decatur County, GA, Dodge County, GA, Dougherty County, GA, Early County, GA, Echols County, GA, Evans County, GA, Glynn County, GA, Grady County, GA, Irwin County, GA, Jeff Davis County, GA, Lanier County, GA, Liberty County, GA, Long County, GA, Lowndes County, GA, McIntosh County, GA, Miller County, GA, Mitchell County, GA, Montgomery County, GA, Pierce County, GA, Seminole County, GA, Tattnall County, GA, Telfair County, GA, Thomas County, GA, Tift County, GA, Toombs County, GA, Turner County, GA, Ware County, GA, Wayne County, GA, Wheeler County, GA, Wilcox County, GA, Worth County, GA

The radar

The Moody AFB radar (KVAX), 39 km from the middle of the area, began a volume at 14:30 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

Jacksonville, FL (KJAX), launched 12:00Z, 2.5 hours before the alert went out and 152 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, Jacksonville, 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, Jacksonville, FL at 12:00Z on 2020-04-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 108 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
1362 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
108 m²/s²
0-3 km storm-relative helicity
225 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, 2:28 AM CDTMesoscale DiscussionSPCBaldwin, Choctaw, Clarke, Conecuh, Escambia, Mobile and 2 more92 min
Apr 23, 4:05 AM CDTTornado WatchSPCBaldwin, Barbour, Bullock, Butler, Choctaw, Clarke and 14 more11 hr
Apr 23, 7:43 AM CDTMesoscale DiscussionSPCBaldwin, Barbour, Butler, Coffee, Conecuh, Covington and 9 more92 min
Apr 23, 1:37 PM CDTMesoscale DiscussionSPCChoctaw, Clarke, Greene, Hale, Marengo, Perry and 3 more113 min
Apr 23, 4:06 PM CDTSevere Thunderstorm WatchSPCAutauga, Bibb, Chambers, Chilton, Choctaw, Clarke and 17 more113 min
Apr 23, 9:52 AM CDTTornado WatchSPCFranklin, Gadsden, Gulf, Hamilton, Jefferson, Leon and 4 more6 hr
Apr 23, 12:05 PM CDTMesoscale DiscussionSPCBay, Escambia, Okaloosa, Santa Rosa, Walton, Washington55 min
Apr 23, 2:28 PM CDTMesoscale DiscussionSPCBay, Calhoun, Franklin, Gulf, Jefferson, Leon and 6 more62 min
Apr 23, 2:47 PM CDTTornado WatchSPCBay, Calhoun, Dixie, Franklin, Gadsden, Gulf and 11 more6 hr
Apr 23, 5:09 PM CDTMesoscale DiscussionSPCAlachua, Baker, Bradford, Calhoun, Clay, Columbia and 17 more96 min
Apr 23, 5:52 PM CDTTornado WatchSPCAlachua, Baker, Bradford, Clay, Columbia, Duval and 7 more5 hr
Apr 23, 12:25 PM CDTMesoscale DiscussionSPCAtkinson, Brantley, Clinch, Echols, Lanier, Lowndes and 3 more95 min
Apr 23, 1:22 PM CDTMesoscale DiscussionSPCChatham, Effingham, Screven83 min

Nearby

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