Alert archive / Florida / Mesoscale Discussions in 2021
Mesoscale Discussion 1160
The Storm Prediction Center issued this mesoscale discussion at Jul 6, 2021, 10:34 AM EDT for 18 counties in Florida. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 6, 2021, 10:34 AM EDT (14:34 UTC)
- Expired
- Jul 6, 2021, 1:00 PM EDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch likely
- Chance of a watch
- 80%
Counties Charlotte County, FL, Collier County, FL, DeSoto County, FL, Glades County, FL, Hardee County, FL, Hendry County, FL, Hernando County, FL, Highlands County, FL, Hillsborough County, FL, Lee County, FL, Manatee County, FL, Monroe County, FL, Osceola County, FL, Pasco County, FL, Pinellas County, FL, Polk County, FL, Sarasota County, FL, Sumter County, FL
The radar
The Tampa radar (KTBW), 132 km from the middle of the area, began a volume at 14:34 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
Tampa Bay, FL (KTBW), launched 12:00Z, 2.6 hours before the alert went out and 132 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
- 815 J/kg
- Mixed-layer CIN
- -46 J/kg
- Mixed-layer LCL
- 773 m above ground
- 0-6 km bulk shear
- 9 kt
- 0-1 km storm-relative helicity
- 29 m²/s²
- 0-3 km storm-relative helicity
- 25 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
694
ACUS11 KWNS 061434
SWOMCD
SPC MCD 061434
FLZ000-061700-
Mesoscale Discussion 1160
NWS Storm Prediction Center Norman OK
0934 AM CDT Tue Jul 06 2021
Areas affected...Southwest Florida Peninsula and Florida Keys
Concerning...Severe potential...Watch likely
Valid 061434Z - 061700Z
Probability of Watch Issuance...80 percent
SUMMARY...The risk for a few tornadoes will increase through the
late morning and afternoon in association with Tropical Storm Elsa.
DISCUSSION...Tropical Storm Elsa was located approximately 55 miles
west-northwest of Key West, FL at 14z and continuing to move
north-northwest at 12 mph (see the most recent NHC advisory for
complete details). Latest radar data from KBYX sampled 0-1 km SRH
in excess of 200 m2/s2, and stronger convective elements were
exhibiting transient rotation offshore of Monroe County. As the
center of Elsa continues moving north-northwest while slowly
strengthening today, low-level wind fields over southwest/central FL
will strengthen. Widespread dew points in the 70s will contribute
to moderate SBCAPE, and these conditions will become more favorable
for a few tornadoes to develop within outer bands from the FL Keys
north across southwest and into the central FL peninsula through
this afternoon, likely continuing into the evening.
Observational trends are being monitored and a Tornado Watch is
likely prior to 17z.
..Bunting/Guyer.. 07/06/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MFL...MLB...KEY...TBW...
LAT...LON 26848270 27728302 28298285 28788227 28738151 28148106
26878095 25668085 25028091 24618138 24468181 24658223
25898230 26848270SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 6, 1:47 PM EDT | Tornado Watch | SPC | Broward, Charlotte, Collier, DeSoto, Glades, Hardee and 15 more | 9 hr |
| Jul 6, 4:55 PM EDT | Mesoscale Discussion | SPC | Charlotte, Collier, DeSoto, Glades, Hardee, Hendry and 9 more | 95 min |
| Jul 6, 7:17 PM EDT | Mesoscale Discussion | SPC | Charlotte, Collier, Lee | 3 hr |
Nearby
Mesoscale Discussions in Florida, 2021Every mesoscale discussion in 2021
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.