Alert archive / Georgia / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 69, NWS Jacksonville, FL

April 20, 202010 counties in Georgia

NWS Jacksonville, FL issued this severe thunderstorm warning at Apr 20, 2020, 2:59 AM EDT for 10 counties in Georgia. It was in force for 46 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Apr 20, 2020, 2:59 AM EDT (06:59 UTC)
Expired
Apr 20, 2020, 3:45 AM EDT
In force
46 min
Issued by
NWS Jacksonville, FL
Area
Storm-based polygon
Tornado
Possible
Hail
0.75 in
Wind
60.0 mph

Counties Appling County, GA, Atkinson County, GA, Bacon County, GA, Brantley County, GA, Charlton County, GA, Clinch County, GA, Glynn County, GA, Pierce County, GA, Ware County, GA, Wayne County, GA

The radar

The Moody AFB radar (KVAX), 83 km from the middle of the area, began a volume at 06:58 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 20, 2:19 AM EDTTornado WatchSPC9 hr

The nearest sounding before it

Jacksonville, FL (KJAX), launched 00:00Z, 7.0 hours before the alert went out and 100 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 00:00Z on 2020-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 262 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2020-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 165 square meters per square second.19395878Sfc1 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
262 J/kg
Mixed-layer CIN
-60 J/kg
Mixed-layer LCL
1615 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
165 m²/s²
0-3 km storm-relative helicity
227 m²/s²
Significant tornado parameter
0.1
Supercell composite
3.2

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Jacksonville, FL wrote its last area forecast discussion before this severe thunderstorm warning went out at Apr 20, 1:29 AM EDT, 1 hour 30 minutes earlier.

Area forecast discussion, Apr 20, 1:29 AM EDT, 1 hour 30 minutes before
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In the hours before

Special weather statement, Apr 19, 9:10 PM EDT, 5 hours 49 minutes before
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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    </section>
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  <script src="index.js"></script>
</body>
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The office that day

Everything else NWS Jacksonville, FL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 19, 9:12 PM EDTSpecial Marine WarningJAX63 min
Apr 20, 4:30 AM EDTSpecial Weather StatementJAXNassau45 min
Apr 20, 4:38 AM EDTSevere Thunderstorm WarningJAXNassau23 min
Apr 20, 4:39 AM EDTSpecial Marine WarningJAX66 min
Apr 20, 5:31 AM EDTSpecial Marine WarningJAX89 min
Apr 20, 5:53 AM EDTSpecial Weather StatementJAXColumbia, Suwannee52 min
Apr 20, 6:09 AM EDTSevere Thunderstorm WarningJAXNassau33 min
Apr 20, 6:34 AM EDTSevere Thunderstorm WarningJAXColumbia, Gilchrist, Suwannee, Union26 min
Apr 20, 6:41 AM EDTSpecial Weather StatementJAXBaker, Nassau49 min
Apr 20, 6:54 AM EDTSevere Thunderstorm WarningJAXBaker, Columbia, Suwannee, Union51 min
Apr 20, 7:00 AM EDTSpecial Marine WarningJAX83 min
Apr 20, 7:03 AM EDTSpecial Marine WarningJAX57 min
Apr 20, 7:09 AM EDTWind AdvisoryJAXDuval, Flagler, Marion8 hr
Apr 20, 7:16 AM EDTSpecial Weather StatementJAXDuval44 min
Apr 20, 7:40 AM EDTSpecial Weather StatementJAXGilchrist50 min
Apr 20, 7:44 AM EDTSevere Thunderstorm WarningJAXDuval, Saint Johns18 min
Apr 20, 8:11 AM EDTSpecial Marine WarningJAX64 min
Apr 20, 8:43 AM EDTSpecial Weather StatementJAXMarion47 min
Apr 20, 9:09 AM EDTSpecial Weather StatementJAXPutnam51 min
Apr 20, 9:17 AM EDTSpecial Weather StatementJAXMarion43 min
Apr 20, 9:22 AM EDTSevere Thunderstorm WarningJAXMarion38 min
Apr 20, 9:54 AM EDTSevere Thunderstorm WarningJAXMarion51 min
Apr 20, 10:00 AM EDTSpecial Weather StatementJAXFlagler, Marion45 min
Apr 20, 10:10 AM EDTTornado WarningJAXMarion12 min
Apr 20, 10:17 AM EDTTornado WarningJAXMarion8 min
Apr 19, 9:10 PM EDTSpecial Weather StatementJAXGlynn20 min
Apr 20, 3:17 AM EDTSevere Thunderstorm WarningJAXAppling, Atkinson, Bacon, Clinch, Coffee, Echols and 3 more43 min
Apr 20, 3:35 AM EDTSevere Thunderstorm WarningJAXAppling, Bacon, Brantley, Camden, Charlton, Glynn and 3 more40 min
Apr 20, 3:58 AM EDTSevere Thunderstorm WarningJAXAppling, Atkinson, Bacon, Brantley, Clinch, Coffee and 4 more47 min
Apr 20, 4:58 AM EDTSpecial Weather StatementJAXGlynn32 min
Apr 20, 5:10 AM EDTSevere Thunderstorm WarningJAXBrantley, Glynn, Wayne24 min
Apr 20, 5:23 AM EDTSpecial Weather StatementJAXGlynn52 min
Apr 20, 5:26 AM EDTSpecial Weather StatementJAXCharlton49 min
Apr 20, 5:34 AM EDTSevere Thunderstorm WarningJAXBrantley, Camden, Glynn30 min
Apr 20, 5:57 AM EDTSpecial Weather StatementJAXCamden48 min

Nearby

Severe Thunderstorm Warnings in Georgia, 2020Every severe thunderstorm warning 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.