Mesoscale Discussion 401

Issued

Apr 20, 2021, 4:35 PM EDT (20:35 UTC)

Expired

Apr 20, 2021, 6:30 PM EDT

In force

115 min

Issued by

the Storm Prediction Center

Concerning

Severe potential...watch unlikely

Chance of a watch

5%

Counties Brevard County, FL, Hardee County, FL, Highlands County, FL, Hillsborough County, FL, Indian River County, FL, Okeechobee County, FL, Orange County, FL, Osceola County, FL, Polk County, FL, Saint Lucie County, FL

The Tampa radar (KTBW), 87 km from the middle of the area, began a volume at 20:35 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.

586 
ACUS11 KWNS 202036
SWOMCD
SPC MCD 202035 
FLZ000-202230-

Mesoscale Discussion 0401
NWS Storm Prediction Center Norman OK
0335 PM CDT Tue Apr 20 2021

Areas affected...Central Florida

Concerning...Severe potential...Watch unlikely 

Valid 202035Z - 202230Z

Probability of Watch Issuance...5 percent

SUMMARY...Potential exists for a few marginally organized storms
this afternoon in central Florida. The primary threats will be
strong/damaging wind gusts and marginally severe hail. A low-end
tornado threat exists for storms near the surface boundary. A watch
is unlikely.

DISCUSSION...Weak mid-level height falls and strong surface heating
in the wake of early convection has contributed to boundary-layer
destabilization in central Florida. Current objective analyses show
around 500-1000 J/kg MLCAPE. Deep-layer shear is relatively modest,
particularly south of the surface boundary in the Orlando vicinity.
KMLB radar imagery shows loosely organized convection north of Lake
Okeechobee. Though unclear, these storms may intensify as they
mature and approach the eastern coast. The relatively greater threat
for severe weather is likely along the boundary north of the current
activity. Visible satellite shows a slight increase in cumulus
development. However, temperatures are only in the upper 70s F here
on account of greater cloud cover during much of the day. As such,
storm initiation is less certain. Isolated wind gusts and marginally
severe hail are possible. Though potential is low, the threat for a
brief, weak tornado would be maximized with any activity near the
surface boundary.

Lack of coverage and the overall marginal threat is likely to
preclude watch issuance this afternoon.

..Wendt/Guyer.. 04/20/2021

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

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

LAT...LON   27478217 27858241 28168249 28488219 28548119 28218033
            27498017 27308053 27228137 27308167 27478217

Mesoscale Discussions in Florida, 2021Every mesoscale discussion in 2021

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.