Alert archive / Florida / Mesoscale Discussions in 2017

Mesoscale Discussion 124

January 22, 201720 counties in Florida

The Storm Prediction Center issued this mesoscale discussion at Jan 22, 2017, 7:32 PM EST for 20 counties in Florida. It was in force for 88 min.

The area

The outline as issued.

The facts

Issued: Jan 22, 2017, 7:32 PM EST (00:32 UTC)
Expired: Jan 22, 2017, 9:00 PM EST
In force: 88 min
Issued by: the Storm Prediction Center

Counties Brevard County, FL, DeSoto County, FL, Flagler County, FL, Hardee County, FL, Hernando County, FL, Highlands County, FL, Hillsborough County, FL, Indian River County, FL, Lake County, FL, Manatee County, FL, Okeechobee County, FL, Orange County, FL, Osceola County, FL, Pasco County, FL, Pinellas County, FL, Polk County, FL, Sarasota County, FL, Seminole County, FL, Sumter County, FL, Volusia County, FL

The radar

The Tampa radar (KTBW), 99 km from the middle of the area, began a volume at 00:32 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.

Tornado Watch 24Jan 22, 9:55 PM EST

The nearest sounding before it

Tampa Bay, FL (KTBW), launched 00:00Z, 0.5 hours before the alert went out and 99 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1747 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 673 m above ground
0-6 km bulk shear: 75 kt
0-1 km storm-relative helicity: 439 m²/s²
0-3 km storm-relative helicity: 500 m²/s²
Significant tornado parameter: 5.8
Supercell composite: 22.7

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.

Issued	Product	Office	Counties	Lasted
Jan 22, 8:21 PM EST	Mesoscale Discussion	SPC	Brevard, Broward, Charlotte, Collier, DeSoto, Glades and 19 more	114 min
Jan 22, 9:57 PM EST	Tornado Watch	SPC	Brevard, Broward, Charlotte, Collier, DeSoto, Glades and 15 more	8 hr
Jan 23, 12:18 AM EST	Mesoscale Discussion	SPC	Broward, Collier, Glades, Hendry, Indian River, Martin and 5 more	117 min
Jan 23, 2:22 AM EST	Mesoscale Discussion	SPC	Broward, Miami-Dade, Monroe	83 min
Jan 23, 4:56 AM EST	Mesoscale Discussion	SPC	Pinellas, Sarasota	94 min

Nearby

Mesoscale Discussions in Florida, 2017 Every mesoscale discussion in 2017

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.