Alert archive / Florida / Mesoscale Discussions in 2021

Mesoscale Discussion 314

April 1, 20218 counties in Florida

The Storm Prediction Center issued this mesoscale discussion at Apr 1, 2021, 12:51 PM EDT for 8 counties in Florida. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued: Apr 1, 2021, 12:51 PM EDT (16:51 UTC)
Expired: Apr 1, 2021, 2:15 PM EDT
In force: 84 min
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch unlikely
Chance of a watch: 20%

Counties Broward County, FL, Collier County, FL, Glades County, FL, Hendry County, FL, Martin County, FL, Miami-Dade County, FL, Palm Beach County, FL, Saint Lucie County, FL

The radar

The Miami radar (KAMX), 90 km from the middle of the area, began a volume at 16:52 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 12:00Z, 4.9 hours before the alert went out and 79 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 238 J/kg
Mixed-layer CIN: -21 J/kg
Mixed-layer LCL: 842 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 9 m²/s²
0-3 km storm-relative helicity: -7 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

548 
ACUS11 KWNS 011651
SWOMCD
SPC MCD 011651 
FLZ000-011815-

Mesoscale Discussion 0314
NWS Storm Prediction Center Norman OK
1151 AM CDT Thu Apr 01 2021

Areas affected...Southeastern Florida

Concerning...Severe potential...Watch unlikely 

Valid 011651Z - 011815Z

Probability of Watch Issuance...20 percent

SUMMARY...Scattered strong/severe storms are expected along a cold
front this afternoon and evening. Damaging wind gusts and marginally
severe hail will be possible. A weather watch is unlikely.

DISCUSSION...1630Z obs showed an east-west oriented cold front
bisecting the Florida Peninsula south of Tampa. Surface temperatures
have warmed into the 80s F south of the front over the last few
hours. The warm temperatures in combination with surface dewpoints
in the upper 60s F are supporting MLCAPE between 1000-1500 J/kg.
Continued destabilization should support scattered storm development
along the front over the next couple of hours. Westerly mid-level
flow from the upper trough over the Mid Atlantic is displaced behind
the front suggesting limited shear overlap with the warm sector.
This should result in a messy storm mode of predominately multi-cell
clusters. Damaging wind gusts from wet microbursts and some
marginally severe hail should be the primary low-end severe threats
through this afternoon. A watch is not anticipated but trends will
be monitored.

..Lyons.. 04/01/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...MFL...MLB...TBW...

LAT...LON   25298052 25488087 25798125 26188153 26508169 26698170
            26818166 27188146 27428078 27378033 26998016 26368004
            25848020 25508024 25298052

Nearby

Mesoscale Discussions in Florida, 2021 Every 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.