Alert archive / Florida / Tornado Watches in 2007
Tornado Watch 740
The Storm Prediction Center issued this tornado watch at Dec 16, 2007, 6:15 AM EST for 4 counties in Florida. It was in force for 107 min.
The area
The outline as issued.
The facts
- Issued
- Dec 16, 2007, 6:15 AM EST (11:15 UTC)
- Expired
- Dec 16, 2007, 8:02 AM EST
- In force
- 107 min
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 0.5 in
- Strongest gust expected
- 60 kt
Counties Lake County, FL, Orange County, FL, Seminole County, FL, Volusia County, FL
The radar
The Melbourne radar (KMLB), 110 km from the middle of the area, began a volume at 11:17 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 30%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 10%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 5%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 30%
Warnings issued inside it
2 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 16, 6:35 AM EST | Tornado Warning | MLB | Lake, Volusia | 25 min |
| Dec 16, 6:56 AM EST | Tornado Warning | MLB | Seminole, Volusia | 35 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Tampa Bay, FL (KTBW), launched 00:00Z, 11.3 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.
- Mixed-layer CAPE
- 660 J/kg
- Mixed-layer CIN
- -33 J/kg
- Mixed-layer LCL
- 839 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km storm-relative helicity
- 129 m²/s²
- 0-3 km storm-relative helicity
- 143 m²/s²
- Significant tornado parameter
- 0.3
- Supercell composite
- 2.3
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 15, 9:19 PM EST | Mesoscale Discussion | SPC | Alachua, Baker, Bradford, Citrus, Clay, Columbia and 14 more | 116 min |
| Dec 15, 9:42 PM EST | Tornado Watch | SPC | Alachua, Baker, Bradford, Citrus, Clay, Columbia and 24 more | 8 hr |
| Dec 16, 12:29 AM EST | Mesoscale Discussion | SPC | Alachua, Baker, Bradford, Citrus, Clay, Columbia and 24 more | 2 hr |
| Dec 16, 3:16 AM EST | Mesoscale Discussion | SPC | Alachua, Baker, Bradford, Citrus, Clay, Columbia and 25 more | 119 min |
| Dec 16, 5:10 AM EST | Mesoscale Discussion | SPC | Flagler, Hernando, Hillsborough, Lake, Marion, Orange and 4 more | 65 min |
| Dec 16, 7:32 AM EST | Mesoscale Discussion | SPC | Orange, Seminole, Volusia | 58 min |
Nearby
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.