Mesoscale Discussion 57

Issued

Feb 6, 2021, 1:46 PM EST (18:46 UTC)

Expired

Feb 6, 2021, 4:15 PM EST

In force

2 hr

Issued by

the Storm Prediction Center

Concerning

Severe potential...watch possible

Chance of a watch

40%

Counties Brevard County, FL, Hardee County, FL, Hernando County, FL, Highlands County, FL, Hillsborough County, FL, Indian River County, FL, Manatee County, FL, Orange County, FL, Osceola County, FL, Pasco County, FL, Polk County, FL, Sumter County, FL

The Tampa radar (KTBW), 87 km from the middle of the area, began a volume at 18:48 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.

• Tornado Watch 5Feb 6, 4:20 PM EST

891 
ACUS11 KWNS 061846
SWOMCD
SPC MCD 061846 
FLZ000-062115-

Mesoscale Discussion 0057
NWS Storm Prediction Center Norman OK
1246 PM CST Sat Feb 06 2021

Areas affected...Parts of the central Florida Peninsula

Concerning...Severe potential...Watch possible 

Valid 061846Z - 062115Z

Probability of Watch Issuance...40 percent

SUMMARY...Increasingly strong, scattered thunderstorm development is
possible through 3-6 PM EST, accompanied by at least some risk for
severe weather.  It is not yet clear that a severe weather watch
will be needed, at least in the near term, but trends will continue
to be monitored for this possibility.

DISCUSSION...Moistening on modest south-southwesterly low-level
flow, including 20-30 kt around the 850 mb level, is contributing to
increasing CAPE in the presence of modestly steep lower/mid
tropospheric lapse rates across much of central and southern
Florida.  To the north (roughly) of the Tampa, Avon Park, and Vero
Beach areas, this is still generally above a residually cool and
stable near-surface layer, but boundary-layer modification is
ongoing.  Breaks in cloud cover should allow for continued surface
heating through the afternoon, and, beneath broadly cyclonic,
southwesterly mid-level flow, some further strengthening of 850 mb
flow to 30+ kt is forecast.  As this occurs, veering of surface
winds to an increasingly southerly component is expected to be
accompanied by surface dew point increases into the upper 60s/near
70f.

While warm layers aloft are tending to suppress thunderstorm
development, forecast soundings suggest that the low-level warming
and moistening will increasingly overcome this inhibition this
afternoon.  Aided by large-scale ascent associated with warm
advection, and coinciding with an increasingly conducive environment
to boundary-layer based thunderstorm development, isolated supercell
structures appear possible.  Deep-layer sheer is already sufficient,
and with some further enlargement of low-level hodographs through
20-23Z, potential for at least isolated storms capable of producing
severe hail, locally strong surface gusts and some risk for a
tornado or two, probably will increase.

..Kerr/Hart.. 02/06/2021

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

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

LAT...LON   29088230 28658162 28227998 27598035 27168165 27548256
            28248297 29088230

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.