Alert archive / Florida / Mesoscale Discussions in 2021
Mesoscale Discussion 1175
The Storm Prediction Center issued this mesoscale discussion at Jul 7, 2021, 5:42 AM EDT for 25 counties in Florida. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 7, 2021, 5:42 AM EDT (09:42 UTC)
- Expired
- Jul 7, 2021, 7:45 AM EDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 340
All 25 counties
Alachua County, FL, Bradford County, FL, Charlotte County, FL, Citrus County, FL, Columbia County, FL, DeSoto County, FL, Dixie County, FL, Gilchrist County, FL, Hardee County, FL, Hernando County, FL, Highlands County, FL, Hillsborough County, FL, Lafayette County, FL, Lake County, FL, Lee County, FL, Levy County, FL, Marion County, FL, Pasco County, FL, Pinellas County, FL, Polk County, FL, Putnam County, FL, Sumter County, FL, Suwannee County, FL, Taylor County, FL, Union County, FL
The radar
The Tampa radar (KTBW), 58 km from the middle of the area, began a volume at 09:42 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 00:00Z, 9.7 hours before the alert went out and 58 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
- 46 J/kg
- Mixed-layer CIN
- -60 J/kg
- Mixed-layer LCL
- 1020 m above ground
- 0-6 km bulk shear
- 3 kt
- 0-1 km storm-relative helicity
- 60 m²/s²
- 0-3 km storm-relative helicity
- 266 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
485
ACUS11 KWNS 070942
SWOMCD
SPC MCD 070942
FLZ000-071145-
Mesoscale Discussion 1175
NWS Storm Prediction Center Norman OK
0442 AM CDT Wed Jul 07 2021
Areas affected...northern...western...and central portions of the
Florida Peninsula
Concerning...Tornado Watch 340...
Valid 070942Z - 071145Z
The severe weather threat for Tornado Watch 340 continues.
SUMMARY...Risk for brief tornadoes continues.
DISCUSSION...Little change with respect to tornado risk is evident
across Florida at this time, as the center of Elsa (now roughly 70
miles south-southwest of Cross City) continues drifting slowly
northward.
Brief/rather weak, transient circulations continue to be observed in
WSR-88D storm-relative velocity data, largely within the primary
convective band arcing from near Fort Myers, to north-northeast to
the Orlando area, and then north-northwest through Gainesville.
Over the past 1-2 hours, a few transient circulations have been
observed from the Ocala to the Gainesville vicinity, near and just
outside of the northern fringe of WW 340. With time, as the center
of Elsa continues shifting northward, areas north and northwest of
the current watch will be monitored for any possible increase in
tornado potential.
..Goss.. 07/07/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MFL...MLB...TBW...JAX...TAE...
LAT...LON 27318133 25988174 25588234 26168262 27268208 27768264
27998302 28588310 28938371 29588394 30268378 30468323
30258236 29628155 27318133SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 6, 10:37 PM EDT | Tornado Watch | SPC | Alachua, Charlotte, Citrus, Collier, DeSoto, Gilchrist and 22 more | 9 hr |
| Jul 6, 11:59 PM EDT | Mesoscale Discussion | SPC | Charlotte, DeSoto, Hardee, Hillsborough | 2 hr |
| Jul 7, 3:03 AM EDT | Mesoscale Discussion | SPC | Charlotte, Citrus, DeSoto, Hardee, Hernando, Hillsborough and 5 more | 117 min |
| Jul 7, 6:46 AM EDT | Tornado Watch | SPC | Baker, Bradford, Clay, Columbia, Duval, Hamilton and 4 more | 6 hr |
| Jul 7, 7:06 AM EDT | Mesoscale Discussion | SPC | Charlotte, Citrus, DeSoto, Hardee, Hernando, Highlands and 10 more | 54 min |
| Jul 7, 10:30 AM EDT | Mesoscale Discussion | SPC | Baker, Bradford, Clay, Columbia, Duval, Hamilton and 3 more | 2 hr |
| Jul 7, 12:28 PM EDT | Mesoscale Discussion | SPC | Baker, Bradford, Clay, Columbia, Duval, Nassau and 1 more | 2 hr |
| Jul 7, 1:04 PM EDT | Tornado Watch | SPC | Baker, Bradford, Clay, Columbia, Duval, Hamilton and 3 more | 7 hr |
| Jul 7, 4:47 PM EDT | Mesoscale Discussion | SPC | Baker, Clay, Columbia, Duval, Nassau, Saint Johns and 1 more | 118 min |
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.