Alert archive / Florida / Mesoscale Discussions in 2015

Mesoscale Discussion 451

April 25, 20156 counties in Alabama; 14 counties in Florida; 14 counties in Georgia

The Storm Prediction Center issued this mesoscale discussion at Apr 25, 2015, 7:41 AM CDT for 6 counties in Alabama; 14 counties in Florida; 14 counties in Georgia. It was in force for 94 min.

The area

The outline as issued.

The facts

Issued
Apr 25, 2015, 7:41 AM CDT (12:41 UTC)
Expired
Apr 25, 2015, 9:15 AM CDT
In force
94 min
Issued by
the Storm Prediction Center
All 34 counties

Coffee County, AL, Covington County, AL, Dale County, AL, Geneva County, AL, Henry County, AL, Houston County, AL, Bay County, FL, Calhoun County, FL, Gadsden County, FL, Holmes County, FL, Jackson County, FL, Jefferson County, FL, Leon County, FL, Liberty County, FL, Madison County, FL, Okaloosa County, FL, Santa Rosa County, FL, Wakulla County, FL, Walton County, FL, Washington County, FL, Baker County, GA, Brooks County, GA, Calhoun County, GA, Colquitt County, GA, Cook County, GA, Decatur County, GA, Dougherty County, GA, Early County, GA, Grady County, GA, Lowndes County, GA, Miller County, GA, Mitchell County, GA, Seminole County, GA, Thomas County, GA

The radar

The Eglin Afb radar (KEVX), 58 km from the middle of the area, began a volume at 12:44 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, 0.7 hours before the alert went out and 105 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 2015-04-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 215 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 2015-04-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 304 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
215 J/kg
Mixed-layer CIN
-111 J/kg
Mixed-layer LCL
704 m above ground
0-6 km bulk shear
61 kt
0-1 km storm-relative helicity
304 m²/s²
0-3 km storm-relative helicity
365 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.3

Open this sounding in Storm Lab

The text

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

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 25, 12:50 AM CDTTornado WatchSPCDallas, Fayette, Greene, Hale, Lamar, Marengo and 4 more6 hr
Apr 25, 2:07 AM CDTMesoscale DiscussionSPCChoctaw, Greene, Pickens, Sumter, Tuscaloosa83 min
Apr 25, 4:12 AM CDTMesoscale DiscussionSPCBaldwin, Butler, Choctaw, Clarke, Conecuh, Dallas and 9 more63 min
Apr 25, 5:00 AM CDTTornado WatchSPCAutauga, Baldwin, Barbour, Bullock, Butler, Clarke and 18 more7 hr
Apr 25, 9:35 AM CDTMesoscale DiscussionSPCBaldwin, Mobile, Washington115 min
Apr 25, 1:36 PM CDTSevere Thunderstorm WatchSPCBaldwin, Butler, Clarke, Conecuh, Covington, Crenshaw and 5 more4 hr
Apr 25, 1:50 PM CDTMesoscale DiscussionSPCBaldwin, Butler, Clarke, Conecuh, Covington, Crenshaw and 4 more85 min
Apr 25, 2:10 PM CDTMesoscale DiscussionSPCAutauga, Bibb, Bullock, Calhoun, Chambers, Chilton and 19 more95 min
Apr 25, 3:07 PM CDTSevere Thunderstorm WatchSPCBarbour, Coffee, Dale, Geneva, Henry, Houston and 1 more7 hr
Apr 25, 4:38 PM CDTSevere Thunderstorm WatchSPCBullock, Chambers, Clay, Lee, Macon, Randolph and 2 more5 hr
Apr 25, 8:08 AM CDTTornado WatchSPCBaker, Calhoun, Columbia, Duval, Franklin, Gadsden and 11 more7 hr
Apr 25, 11:20 AM CDTMesoscale DiscussionSPCColumbia, Gadsden, Hamilton, Jefferson, Lafayette, Leon and 5 more85 min
Apr 25, 2:30 PM CDTMesoscale DiscussionSPCBaker, Columbia, Duval, Gadsden, Hamilton, Jefferson and 5 more60 min
Apr 25, 6:19 PM CDTMesoscale DiscussionSPCCalhoun, Franklin, Gadsden, Gulf, Hamilton, Jackson and 6 more56 min
Apr 25, 5:07 PM CDTMesoscale DiscussionSPCBryan, Bulloch, Burke, Candler, Chatham, Effingham and 7 more53 min
Apr 25, 5:28 PM CDTSevere Thunderstorm WatchSPCBryan, Bulloch, Burke, Candler, Chatham, Effingham and 7 more4 hr

Nearby

Mesoscale Discussions in Florida, 2015Mesoscale Discussions in Georgia, 2015Mesoscale Discussions in Alabama, 2015Every mesoscale discussion in 2015

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.