Alert archive / Florida / Mesoscale Discussions in 2021
Mesoscale Discussion 1174
The Storm Prediction Center issued this mesoscale discussion at Jul 7, 2021, 3:03 AM EDT for 11 counties in Florida. It was in force for 117 min.
The area
The outline as issued.
The facts
- Issued
- Jul 7, 2021, 3:03 AM EDT (07:03 UTC)
- Expired
- Jul 7, 2021, 5:00 AM EDT
- In force
- 117 min
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 340
Counties Charlotte County, FL, Citrus County, FL, DeSoto County, FL, Hardee County, FL, Hernando County, FL, Hillsborough County, FL, Lee County, FL, Levy County, FL, Pasco County, FL, Polk County, FL, Sumter County, FL
The radar
The Tampa radar (KTBW), 21 km from the middle of the area, began a volume at 07:04 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 nearest sounding before it
Tampa Bay, FL (KTBW), launched 00:00Z, 7.1 hours before the alert went out and 21 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.
326
ACUS11 KWNS 070704
SWOMCD
SPC MCD 070703
FLZ000-070900-
Mesoscale Discussion 1174
NWS Storm Prediction Center Norman OK
0203 AM CDT Wed Jul 07 2021
Areas affected...western and central Florida
Concerning...Tornado Watch 340...
Valid 070703Z - 070900Z
The severe weather threat for Tornado Watch 340 continues.
SUMMARY...Risk for brief tornadoes continues across portions of
western and central Florida.
DISCUSSION...Latest radar and satellite loops show the center of
Tropical Storm Elsa west of Tampa, moving slowly northward -- in
line with the latest NHC track forecast.
East of the center, several spiral bands are noted in radar, with
the most pronounced band onshore, extending in an arc from roughly
Fort Myers to Cross City. Within this band, several
occasional/somewhat transient circulations have been observed, some
cyclically weakening and then increasing again. While not
particularly strong, any of these circulations -- aided by 35 kt
0-1km shear per the latest TBW WSR-88D VWP -- may be associated with
brief tornadic spin-ups.
..Goss.. 07/07/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MFL...MLB...TBW...JAX...
LAT...LON 26308255 26928221 27308222 27628234 28028282 29228325
29378283 29088200 28438145 27258140 26628154 26178195
26308255SPC 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, 5:42 AM EDT | Mesoscale Discussion | SPC | Alachua, Bradford, Charlotte, Citrus, Columbia, DeSoto and 19 more | 2 hr |
| 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.