-- Discussion containing changed information from previous version are highlighted. --
852
FXUS62 KTBW 121831
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
231 PM EDT Sun May 12 2024

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

.DISCUSSION...
-- Changed Discussion --
Issued at 230 PM EDT Sun May 12 2024

Shortwave ridging continues to build across the region through the
remainder of the day and into Monday as surface high pressure slides
out into the Atlantic. This will result in low level flow becoming
south-southeasterly by Monday and bring a quick recovery to more
humid conditions after yesterday`s cold front brought us a brief
reprieve from higher dewpoint values in recent days. With the return
of deeper moisture and assistance from a sea breeze collision
inland, scattered showers and storms are expected to develop during
peak heating hours with highest PoPs (35%-45%) for interior areas.
While this appears to be a typical diurnal sea breeze regime with
greatest precipitation coverage expected during late afternoon and
evening hours, some recent CAM guidance, most notably the HRRR/ARW,
appear to show the potential of a line of storms or an MCS
developing across the Gulf Coast states and possibly tracking
southeastward across the northeastern Gulf of Mexico. It needs to be
noted that this scenario remains highly uncertain at this time but
there should be enough instability in place across the Gulf waters
to provide fuel for this complex of storms if it were to develop and
possibly approach the west central Florida coastline by tomorrow
afternoon and evening. However, that said, mainly thinking that
tomorrow`s convective activity should be mostly due to the typical
sea breeze circulation as there will be shortwave ridging aloft
across our area and the main forcing from the upper level trough and
associated shortwave energy doesn`t arrive until Tuesday but latest
trends will need to be monitored closely.

By Tuesday, an upper level trough will be swinging across the MS and
TN valley with the associated surface low moving into the Ohio
Valley. This will allow a warm front to push northward across the
area Tuesday morning and eventually the low pressure system`s cold
front will approach the area by Tuesday night. Given that the
environment on Tuesday will be characterized by much better forcing
for ascent and dynamics with plenty of wind shear, it appears that a
MCS is likely to develop Monday night into Tuesday morning across
the I-10 corridor and Gulf Coast states with potential for this
feature to track towards our area (possibly similar to Monday`s
outcome if it were to develop). This could result in some potential
for strong to severe storms across the northern portions of our
forecast area on Tuesday but the TBW CWA will be on the southern
edge of the highest severe risk as we will have ridging aloft across
the Caribbean possibly hanging on just tough enough to keep the
worst of the activity just to the north. This will also need to be
monitored closely as the aforementioned shear values are more than
enough to support organized convection but for now confidence is
lower than ideal in the southern extent of the impacts. As a result,
SPC has included portions of Levy County in a Marginal Risk (level 1
out of 5) for Tuesday with a larger area of risk northward into
north FL and GA/SC but be sure to stay tuned for further forecast
updates in the coming days as details become more clear.

The aforementioned cold front will slowly approach our area Tuesday
night into Wednesday and eventually stall near or just north of our
area into late week. This feature will keep additional shower and
storm chances in place with unsettled weather continuing through the
end of the week , though transient ridging quickly slides across the
area on Thursday so this should support a decrease in overall
precipitation coverage by late week. The active weather pattern
should then continue into next weekend with continued rain chances
as the active subtropical jet remains in place across the southern
tier of the US, but once again the strength of upper ridging to the
south will need to be monitored as the main disturbances embedded
within the flow aloft may be mostly confined to the north of the
area.
-- End Changed Discussion --

&&

.AVIATION...
(18Z TAFS)
Issued at 1254 PM EDT Sun May 12 2024
VFR conditions will prevail throughout the period as high
pressure remains in control. This feature will shift out into the
Atlantic tonight and winds will shift to the SSE overnight into
Monday but eventually shift onshore as the sea breeze pushes
inland by the afternoon. A few showers and thunderstorms may also
develop tomorrow but this activity appears to mainly develop
inland and away from most terminals, though highest precip chances
at this point look to be at KLAL where VCTS may eventually need
to be added in subsequent TAF issuances.

&&

.MARINE...
-- Changed Discussion --
Issued at 230 PM EDT Sun May 12 2024
High pressure will remain in place through the end of the weekend
and start to shift further offshore into the Atlantic by early
next week a frontal system approaches the area by Tuesday. Ahead
of the cold front associated with this system, winds become
southerly and increase over the coming days with wind speeds
possibly approaching advisory criteria on Tuesday. Scattered
showers and thunderstorms will accompany the cold front and there
is a possibility for one or several waves of storms moving across
the area through Tuesday. The cold front then stalls across the
northern Gulf waters by the middle of the week with chances for
scattered showers and storms continuing. In addition, increasing
winds will also support building seas to 2-4 ft into mid week and
though seas may briefly subside as the stalled front weakens, seas
should remain elevated through the end of the week as additional
disturbances approach the area.
-- End Changed Discussion --

&&

.FIRE WEATHER...
-- Changed Discussion --
Issued at 230 PM EDT Sun May 12 2024
Elevated fire weather concerns remain in place through the end of
the weekend as critically low RH values are expected,
particularly interior areas. However, deeper moisture will start
moving into the area by early next week and this will allow
humidity values to recover in the coming days. In addition, rain
chances will increase as a series of disturbances approach the
area, possibly bringing needed rainfall and relief to the dry
fuels.
-- End Changed Discussion --

&&

.PRELIMINARY POINT TEMPS/POPS...
TPA  75  92  78  91 /   0  30  20  30
FMY  73  94  76  93 /   0  30  10  20
GIF  71  94  73  96 /   0  60  20  40
SRQ  72  93  76  92 /   0  20  20  20
BKV  67  94  70  93 /   0  40  20  50
SPG  77  90  79  89 /   0  30  30  30

&&

Sea Breeze Thunderstorm Regime For Monday: 7
Sea Breeze Thunderstorm Regime For Tuesday: 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...Hubbard
UPPER AIR/CLIMATE...Hubbard