Alert archive / Florida / Mesoscale Discussions in 2012

Mesoscale Discussion 1792

August 20, 201217 counties in Florida

The Storm Prediction Center issued this mesoscale discussion at Aug 20, 2012, 12:28 PM EDT for 17 counties in Florida. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued
Aug 20, 2012, 12:28 PM EDT (16:28 UTC)
Expired
Aug 20, 2012, 2:00 PM EDT
In force
92 min
Issued by
the Storm Prediction Center
Chance of a watch
40%

Counties Alachua County, FL, Baker County, FL, Bradford County, FL, Clay County, FL, Columbia County, FL, Dixie County, FL, Duval County, FL, Gilchrist County, FL, Hamilton County, FL, Lafayette County, FL, Levy County, FL, Madison County, FL, Nassau County, FL, Putnam County, FL, Suwannee County, FL, Taylor County, FL, Union County, FL

The radar

The Jacksonville radar (KJAX), 126 km from the middle of the area, began a volume at 16:31 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

Jacksonville, FL (KJAX), launched 12:00Z, 4.5 hours before the alert went out and 127 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 2012-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1896 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 12:00Z on 2012-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 76 square meters per square second.193958Sfc1 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
1896 J/kg
Mixed-layer CIN
-13 J/kg
Mixed-layer LCL
622 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
76 m²/s²
0-3 km storm-relative helicity
124 m²/s²
Significant tornado parameter
0.6
Supercell composite
5.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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Nearby

Mesoscale Discussions in Florida, 2012Every mesoscale discussion in 2012

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.