Alert archive / Florida / Tornado Watches in 2008
Tornado Watch 837
The Storm Prediction Center issued this tornado watch at Aug 18, 2008, 12:30 PM EDT for 7 counties in Florida. It was in force for 10 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 18, 2008, 12:30 PM EDT (16:30 UTC)
- Expired
- Aug 18, 2008, 10:55 PM EDT
- In force
- 10 hr
- Issued by
- the Storm Prediction Center
- Strongest gust expected
- 60 kt
Counties Broward County, FL, Collier County, FL, Glades County, FL, Hendry County, FL, Miami-Dade County, FL, Monroe County, FL, Palm Beach County, FL
The radar
The Miami radar (KAMX), 78 km from the middle of the area, began a volume at 16:30 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
- 40%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 20%
- One or more gusts of 65 knots or more
- 20%
- 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
- 40%
Warnings issued inside it
12 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 12:37 PM EDT | Tornado Warning | KEY | Monroe | 23 min |
| Aug 18, 1:01 PM EDT | Tornado Warning | KEY | Monroe | 22 min |
| Aug 18, 1:12 PM EDT | Tornado Warning | KEY | Monroe | 33 min |
| Aug 18, 2:19 PM EDT | Tornado Warning | KEY | Monroe | 26 min |
| Aug 18, 2:52 PM EDT | Tornado Warning | MFL | Miami-Dade | 23 min |
| Aug 18, 3:01 PM EDT | Tornado Warning | MFL | Miami-Dade | 29 min |
| Aug 18, 4:40 PM EDT | Tornado Warning | MFL | Broward, Collier, Miami-Dade | 20 min |
| Aug 18, 5:23 PM EDT | Tornado Warning | MFL | Palm Beach | 22 min |
| Aug 18, 5:45 PM EDT | Tornado Warning | MFL | Broward | 15 min |
| Aug 18, 9:45 PM EDT | Tornado Warning | MFL | Collier | 15 min |
| Aug 18, 10:01 PM EDT | Tornado Warning | MFL | Broward | 14 min |
| Aug 18, 10:03 PM EDT | Tornado Warning | MFL | Collier | 15 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
Miami, FL (KMFL), launched 12:00Z, 4.5 hours before the alert went out and 86 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
- 2466 J/kg
- Mixed-layer CIN
- -3 J/kg
- Mixed-layer LCL
- 776 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- 43 m²/s²
- 0-3 km storm-relative helicity
- 59 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 8:14 AM EDT | Mesoscale Discussion | SPC | Broward, Miami-Dade, Monroe | 61 min |
| Aug 18, 3:44 PM EDT | Mesoscale Discussion | SPC | Broward, Collier, Hendry, Miami-Dade, Monroe, Palm Beach | 2 hr |
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.