Alert archive / Florida / Mesoscale Discussions in 2017
Mesoscale Discussion 955
The Storm Prediction Center issued this mesoscale discussion at Jun 6, 2017, 5:01 AM EDT for Monroe County, Florida. It was in force for 119 min.
The area
The outline as issued.
The facts
- Issued
- Jun 6, 2017, 5:01 AM EDT (09:01 UTC)
- Expired
- Jun 6, 2017, 7:00 AM EDT
- In force
- 119 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 20%
County Monroe County, FL
The radar
The Miami radar (KAMX), 66 km from the middle of the area, began a volume at 09:04 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
Miami, FL (KMFL), launched 00:00Z, 9.0 hours before the alert went out and 68 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
- 894 J/kg
- Mixed-layer CIN
- -22 J/kg
- Mixed-layer LCL
- 956 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- 52 m²/s²
- 0-3 km storm-relative helicity
- 170 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 1.7
The text
As transmitted.
574
ACUS11 KWNS 060901
SWOMCD
SPC MCD 060901
FLZ000-061100-
Mesoscale Discussion 0955
NWS Storm Prediction Center Norman OK
0401 AM CDT Tue Jun 06 2017
Areas affected...south Florida
Concerning...Severe potential...Watch unlikely
Valid 060901Z - 061100Z
Probability of Watch Issuance...20 percent
SUMMARY...A brief tornado or two will remain possible through at
least 12Z, mainly over the western half of south Florida. Overall
threat is somewhat marginal and is limited spacial extent. A WW will
probably not be needed unless trends begin to suggest a more robust
threat will expand farther east toward the Miami area.
DISCUSSION...Early this morning storms continue to develop over
south FL /fostered by a 35 kt southwesterly low-level jet/ and train
eastward along an outflow boundary. The atmosphere over south
Florida is moderately unstable with 1500 J/kg MUCAPE. VWP data show
weakly veering low-level winds, relatively small 0-1 km hodographs
and around 35-40 kt surface to 6 km shear. While this environment is
supportive of some storms to develop supercell structures, the
relatively modest low-level hodograph size appears to be a limiting
factor for a more robust tornado threat. However, some enhancement
in low-level vorticity may exist as storms move along and interact
with the quasi-stationary outflow boundary, and a brief tornado or
two will remain possible. Tendency has been for storms to weaken as
they move farther inland and toward the more populated areas along
the east coast. As long as this trend continues, a WW will not be
necessary, but area will continue to be monitored.
..Dial/Goss.. 06/06/2017
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MFL...
LAT...LON 26248077 26038059 25638071 25478102 25968164 26108118
26248077SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 6, 4:54 PM EDT | Mesoscale Discussion | SPC | Glades, Hendry, Highlands, Indian River, Martin, Okeechobee and 2 more | 3 hr |
Nearby
Mesoscale Discussions in Florida, 2017Every mesoscale discussion in 2017
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.