109
FXUS62 KTBW 131855
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
255 PM EDT Mon May 13 2024

...New DISCUSSION, MARINE, FIRE WEATHER...

.DISCUSSION...
Issued at 241 PM EDT Mon May 13 2024

Scattered convection will continue to increase in coverage across
interior areas later today as the sea breeze spreads inland and
collides with the east coast sea breeze. A few strong to severe
storms capable of damaging winds and hail will be possible with this
activity given CAPE values in the 1500-2000 J/kg range, 0-6 km bulk
shear values of 40-50 kts, and 500mb temps around -8C. Meanwhile,
there is potential for additional convective activity from an
upstream MCS that is tracking across the FL Panhandle/northern
Gulf coast region this afternoon. While there still remains
uncertainty on the intensity of this complex and how organized it
will be by the time is approaches the coast this evening, recent
trends do suggest that the activity should generally be on a
weakening trend as it becomes increasingly removed from the better
upper support to the north. That said, there will still be a
possibility of strong wind gusts, hail, and isolated
tornadoes/waterspouts as this activity moves through this evening.

After tonight`s wave of convection, we will have another MCS to
watch as models show another complex of storms organizing overnight
across east TX/LA and eventually sliding across the northern Gulf
coast into Tuesday as an upper level trough swings across the
Mississippi Valley. This secondary MCS has the potential to be a bit
more potent with increased forcing for ascent with the approach of
the upper trough and an environment that will be characterized by
strong dynamics with plenty of shear. While there remains
substantial uncertainty in the track of the MCS and how well it can
hold together, this will be something that will need to be monitored
closely as there could a damaging wind and tornado risk should this
feature maintain its intensity. As a result, the latest Day 2
Outlook from SPC has placed portions Levy County in a Slight risk
and a Marginal risk extending southward into Tampa Bay.

The cold front associated with the aforementioned upper level trough
will approach our area Tuesday night and around central Florida into
Wednesday. This frontal boundary will provide a focus for additional
convection on Wednesday with models showing good instability with
values up to around 2000 J/kg, 500mb temps around -9C/-10C, and an
active subtropical jet of 70-80 kts. Thus, another round of strong
to severe storms remains possible and will include a larger portion
of the CWA with nearly everywhere included in a Marginal risk except
Charlotte and Lee counties where damaging winds and hail will be the
primary threats.

Somewhat quieter weather arrives late in the week as ridging moves
across the region Thursday, though there should be enough deeper
moisture to support additional shower and storm chances for at least
areas south of I-4 where the better moisture quality is expected to
be. However, models show the quasi-situational frontal boundary across
north central Florida lifting back north as a warm front on Friday
as surface low pressure moves across the MS Valley. This feature
appears to keep the active weather streak in place into the weekend
as the system will push a cold front towards the area with another
round of convection expected.

&&

.AVIATION...
(18Z TAFS)
Issued at 128 PM EDT Mon May 13 2024

VFR conditions will generally be in place through the remainder of
the day but scattered showers and storms will develop across
interior areas and this activity may be in close enough proximity
to KLAL for some brief periods of restrictions. There will also
be a line of showers and storms that approaches the area mainly
north of Tampa Bay by this evening and should generally be on a
weakening trend but some VCSH may be possible at Tampa Bay area
terminals. Otherwise, patchy low stratus overnight may support a
period of MVFR CIGs before VFR conditions return by Tuesday
morning. However, forecast guidance does suggest that another
thunderstorm complex may approach the area by Tuesday afternoon
but forecast confidence is too low to include mention in current
TAF issuance.

&&

.MARINE...
Issued at 241 PM EDT Mon May 13 2024

High pressure will shift further out into the Atlantic and allow a
cold front to approach our area over the next couple of days.
Ahead of this cold front, multiple rounds of showers and
thunderstorms will be possible across the Gulf waters with the
first round expected this evening and the second around on
Tuesday. Isolated waterspouts, strong winds, heavy rain, and
frequent lightning will be possible with this activity. In
addition, winds may approach exercise cautionary levels on Tuesday
outside of thunderstorms as southerly winds increase ahead of the
cold front`s arrival by Wednesday. The cold front will keep a
chance for showers and storms into Wednesday before lower rain
chances arrive later this week as high pressure builds in

&&

.FIRE WEATHER...
Issued at 241 PM EDT Mon May 13 2024

Deeper moisture has moved back into the area and RH values are
expected to remain above critical levels, though values may drop
into the upper 30 percent range at times mainly for areas south of
I-4 over the next couple of days. Otherwise, several rounds of
thunderstorms will move across the area with the first occurring
tonight and the second on Tuesday with highest rain chances across
the Nature Coast. Better rain chances then arrive area-wide by
Wednesday as a cold front stalls across the region.

&&

.PRELIMINARY POINT TEMPS/POPS...
TPA  78  90  79  88 /  40  40  40  70
FMY  77  94  79  92 /  10  10  10  40
GIF  74  95  76  90 /  40  40  30  70
SRQ  77  91  77  90 /  10  20  30  60
BKV  70  93  73  88 /  50  60  50  80
SPG  80  89  80  87 /  30  40  40  60

&&

Sea Breeze Thunderstorm Regime For Tuesday: 5
Sea Breeze Thunderstorm Regime For Wednesday: 5

For additional information on sea breeze regimes, go to:
     https://www.weather.gov/tbw/ThunderstormClimatology

&&

.TBW WATCHES/WARNINGS/ADVISORIES...
FL...None.
Gulf waters...None.

&&

$$

DISCUSSION/AVIATION/MARINE/FIRE WEATHER...Giarratana
DECISION SUPPORT...Delerme
UPPER AIR/CLIMATE...Delerme