Alert archive / Florida / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 166, NWS Jacksonville, FL

June 30, 2020Columbia County, Hamilton County, Florida

NWS Jacksonville, FL issued this severe thunderstorm warning at Jun 30, 2020, 6:12 PM EDT for Columbia County, Hamilton County, Florida. It was in force for 33 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
Jun 30, 2020, 6:12 PM EDT (22:12 UTC)
Expired
Jun 30, 2020, 6:45 PM EDT
In force
33 min
Issued by
NWS Jacksonville, FL
Area
Storm-based polygon
Tornado
Possible
Hail
1.0 in
Wind
60.0 mph

Counties Columbia County, FL, Hamilton County, FL

The radar

The Moody AFB radar (KVAX), 63 km from the middle of the area, began a volume at 22:14 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, 10.2 hours before the alert went out and 145 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 2020-06-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1377 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, Tallahassee Rgnl, FL at 12:00Z on 2020-06-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 8 square meters per square second.1939Sfc1 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
1377 J/kg
Mixed-layer CIN
-52 J/kg
Mixed-layer LCL
883 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
8 m²/s²
0-3 km storm-relative helicity
17 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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 Jun 30, 3:22 PM EDT, 2 hours 50 minutes earlier.

Area forecast discussion, Jun 30, 3:22 PM EDT, 2 hours 50 minutes before
Area Forecast Discussion
National Weather Service Jacksonville FL
322 PM EDT Tue Jun 30 2020

...NUMEROUS SHOWERS AND THUNDERSTORMS THROUGH THE WEEKEND...

.NEAR TERM [Tonight through Wednesday]...Upstream mid-level
shortwave trough moving over ridge has produced storms across se
Ga/ne Fl this afternoon with another area of convection now moving
into interior se Ga. Expect showers and thunderstorms to continue
through the evening with lift from upper trough acting on a moist
and unstable airmass. Storms will produce heavy downpours and
strong gusty winds. Additional shortwave energy on Wednesday will
produce numerous showers and thunderstorms again during the
afternoon and evening.

.SHORT TERM [Wednesday night through Friday night]...Trough axis
at surface and aloft will drop south into s Georgia and become
nearly stationary by Friday as upper low moves off the ne U.S.
coast. Widespread convection will continue across the area due to
abundant moisture and lift. Daytime heating will increase the
areal coverage during the afternoon and evening hours.

.LONG TERM [Saturday Through Tuesday]...Low to mid level
low/trough across the area this weekend will gradually shift east
with models differing with timing in the medium range. Tropical
moisture across the area will continue the threat of heavy
rainfall this weekend into early next week as weak low pressure
forms along surface trough. Numerous showers/storms expected each
day with lingering nighttime convection possible.

&&

.MARINE...High pressure ridge to the south and troughing to the
north will maintain a west to southwesterly flow the next few
days. Showers and thunderstorms will be scattered to numerous
through the weekend as an upper level trough develops over the
southeast.

Rip Currents: Low risk through Wednesday with prevailing offshore
winds.

&&

.PRELIMINARY POINT TEMPS/POPS...

AMG  74  94  73  91  73 /  30  60  40  80  40
SSI  77  92  76  90  77 /  50  50  40  80  50
JAX  76  95  75  93  74 /  50  60  40  80  40
SGJ  75  92  74  92  74 /  50  50  30  80  40
GNV  75  92  74  93  74 /  20  50  50  80  40
OCF  76  93  75  93  74 /  10  40  50  70  40

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...Heat Advisory from 1 PM to 5 PM EDT this afternoon for Clay-
     Inland Duval.
GA...None.
AM...None.
&&

In the hours before

Local storm report, Jun 30, 5:36 PM EDT, 36 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.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>
Special weather statement, Jun 30, 5:36 PM EDT, 36 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.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>
Local storm report, Jun 30, 5:43 PM EDT, 29 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.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>
Special weather statement, Jun 30, 5:45 PM EDT, 27 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.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>
Local storm report, Jun 30, 5:48 PM EDT, 24 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.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>
Special weather statement, Jun 30, 5:49 PM EDT, 23 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.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 30, 4:12 AM EDTHeat AdvisoryJAX11 hr
Jun 30, 2:04 PM EDTSpecial Weather StatementJAXNassau41 min
Jun 30, 2:29 PM EDTSpecial Marine WarningJAX91 min
Jun 30, 2:32 PM EDTSpecial Weather StatementJAXDuval, Nassau58 min
Jun 30, 2:35 PM EDTSpecial Weather StatementJAXBradford, Clay, Union40 min
Jun 30, 2:56 PM EDTSpecial Weather StatementJAXFlagler34 min
Jun 30, 3:02 PM EDTSpecial Weather StatementJAXAlachua, Bradford, Union58 min
Jun 30, 3:09 PM EDTSpecial Weather StatementJAXClay, Duval, Saint Johns51 min
Jun 30, 3:27 PM EDTSpecial Weather StatementJAXDuval33 min
Jun 30, 3:31 PM EDTSevere Thunderstorm WarningJAXClay, Duval, Saint Johns44 min
Jun 30, 3:35 PM EDTSpecial Marine WarningJAX85 min
Jun 30, 3:38 PM EDTSpecial Weather StatementJAXFlagler37 min
Jun 30, 3:44 PM EDTSevere Thunderstorm WarningJAXClay, Putnam, Saint Johns46 min
Jun 30, 3:48 PM EDTSevere Thunderstorm WarningJAXFlagler27 min
Jun 30, 3:52 PM EDTSevere Thunderstorm WarningJAXDuval, Saint Johns39 min
Jun 30, 4:02 PM EDTSpecial Weather StatementJAXPutnam43 min
Jun 30, 4:42 PM EDTSpecial Weather StatementJAXSuwannee48 min
Jun 30, 4:56 PM EDTSpecial Marine WarningJAX64 min
Jun 30, 5:18 PM EDTSpecial Weather StatementJAXColumbia, Hamilton, Suwannee42 min
Jun 30, 5:20 PM EDTSpecial Weather StatementJAXFlagler40 min
Jun 30, 5:45 PM EDTSpecial Weather StatementJAXColumbia, Hamilton45 min
Jun 30, 6:15 PM EDTSpecial Weather StatementJAXPutnam45 min
Jun 30, 6:20 PM EDTSpecial Weather StatementJAXHamilton40 min
Jun 30, 6:33 PM EDTSevere Thunderstorm WarningJAXColumbia, Hamilton, Suwannee27 min
Jun 30, 6:35 PM EDTSpecial Weather StatementJAXBaker40 min
Jun 30, 6:57 PM EDTSpecial Weather StatementJAXHamilton, Suwannee48 min
Jun 30, 6:59 PM EDTSpecial Weather StatementJAXFlagler31 min
Jun 30, 7:12 PM EDTSevere Thunderstorm WarningJAXColumbia, Hamilton, Suwannee48 min
Jun 30, 1:53 PM EDTSpecial Weather StatementJAXCharlton52 min
Jun 30, 3:34 PM EDTSpecial Weather StatementJAXAtkinson, Coffee41 min
Jun 30, 3:48 PM EDTSpecial Weather StatementJAXPierce42 min
Jun 30, 3:57 PM EDTSevere Thunderstorm WarningJAXBrantley, Pierce, Ware48 min
Jun 30, 4:00 PM EDTSevere Thunderstorm WarningJAXCoffee45 min
Jun 30, 4:08 PM EDTSpecial Weather StatementJAXWare52 min
Jun 30, 4:20 PM EDTSpecial Weather StatementJAXAtkinson40 min
Jun 30, 4:23 PM EDTSevere Thunderstorm WarningJAXWare52 min
Jun 30, 4:26 PM EDTSpecial Weather StatementJAXAppling, Bacon, Jeff Davis49 min
Jun 30, 4:35 PM EDTSevere Thunderstorm WarningJAXAtkinson, Clinch, Ware40 min
Jun 30, 4:46 PM EDTSevere Thunderstorm WarningJAXAppling, Bacon, Jeff Davis30 min
Jun 30, 4:49 PM EDTSpecial Weather StatementJAXWayne41 min
Jun 30, 4:54 PM EDTSpecial Weather StatementJAXCoffee51 min
Jun 30, 5:01 PM EDTSpecial Weather StatementJAXClinch, Ware44 min
Jun 30, 5:04 PM EDTSpecial Weather StatementJAXAppling, Wayne41 min
Jun 30, 5:36 PM EDTSpecial Weather StatementJAXClinch39 min
Jun 30, 5:49 PM EDTSpecial Weather StatementJAXCharlton41 min

Nearby

Severe Thunderstorm Warnings in Florida, 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.