Mesoscale Discussion 1919

Issued

Oct 27, 2021, 9:08 PM CDT (02:08 UTC)

Expired

Oct 27, 2021, 10:45 PM CDT

In force

97 min

Issued by

the Storm Prediction Center

Concerning

Tornado watch 543

Counties Baldwin County, AL, Escambia County, AL, Mobile County, AL, Escambia County, FL, Okaloosa County, FL, Santa Rosa County, FL, Jackson County, MS

The Mobile radar (KMOB), 59 km from the middle of the area, began a volume at 02:07 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.

725 
ACUS11 KWNS 280209
SWOMCD
SPC MCD 280208 
FLZ000-ALZ000-MSZ000-280345-

Mesoscale Discussion 1919
NWS Storm Prediction Center Norman OK
0908 PM CDT Wed Oct 27 2021

Areas affected...Portions of the Alabama Panhandle into the western
Florida Peninsula

Concerning...Tornado Watch 543...

Valid 280208Z - 280345Z

The severe weather threat for Tornado Watch 543 continues.

SUMMARY...A brief uptick in tornado potential may be realized in the
next 1-2 hours with semi-discrete supercells ahead of a squall line
within a narrow warm sector.

DISCUSSION...Multiple semi-discrete supercells have recently
developed on the nose of an instability axis, ahead of a loosely
organized MCS/squall line, where occasional bouts of low-level
rotation and a TDS has recently been observed (Jackson County, MS).
These storms are moving ashore amid mid to upper 60sF dewpoints,
yielding 500+ J/kg MLCAPE based on 00Z mesoanalysis. 0154Z MOB VWP
depicts a classic, curved hodograph with over 350 m2/s2 0-1 km SRH,
which should be sufficient given the aforementioned instability to
support an additional brief tornado or two over the next couple of
hours. However, dewpoints drop into the lower 60sF with eastward
extent into the Fl Panhandle, with instability also decreasing and
inhibition increasing. While onshore low-level flow will support
some increase in instability later this evening, the overall
decrease in buoyancy lends less certainty to longer term tornado
potential, especially inland.

..Squitieri/Grams.. 10/28/2021

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

ATTN...WFO...TAE...MOB...LIX...

LAT...LON   30288876 30848864 31308830 31428779 31288711 31068646
            30678634 30358647 30198708 30108816 30288876

Mesoscale Discussions in Alabama, 2021Mesoscale Discussions in Florida, 2021Mesoscale Discussions in Mississippi, 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.