Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Tampa Bay Ruskin Florida
724 am EDT sun Jul 24 2016
VFR will prevail at all terminals through 16z. After 16z
developing shra/tsra may bring brief MVFR/IFR conditions and have
handled with thunderstorms in the vicinity for now. Outside of the convection VFR will
prevail. Southeast winds in the 4 to 6 knot range this morning
will become southwest to west at 7 to 10 knots after 17z at all
coastal terminal sites as the sea breeze develops, except
remaining southeast at klal. Gusts up to 40 knots will be possible
in the vicinity of tsra. VFR with light and variable winds will
return to all sites after 02z tonight as the shra/tsra end.
Prev discussion... /issued 357 am EDT sun Jul 24 2016/
Short term (today - monday)...
the upper level pattern is currently dominated by a sprawling
ridge of high pressure extending from the Desert Southwest through
the mid-Atlantic coast, while a TUTT low moves southwest from
the Atlantic into southern Florida. This TUTT will bring cooler
mid- level temperatures into the forecast area this afternoon, but
will also pull drier air into the northern half of the Florida
Peninsula. As a result, the drier air should slightly suppress the
scattered storms north of Interstate 4 this afternoon, although
the cooler mid-level temperatures south of Interstate 4 could
allow for a few stronger storms to develop.
On Monday, the TUTT will move west into the Gulf with deep
moisture filling back in across the forecast area. Another TUTT
will move west into the Florida Straits, but should have little to
no impact this far north. With the surface ridge still
straddling northern Florida, generally southeast low level flow
will remain in place, favoring a sea breeze collision along or to
the west of the Interstate 75 corridor. Another afternoon of
scattered to numerous thunderstorms will be expected.
Temperatures will remain near to a couple degrees above normal,
with highs in the low 90s, except for some upper 80s along the
coast. Lows tonight will range from the low 70s inland to upper
70s along the coast.
Long term (tuesday through next saturday)...
upper level low will be quickly exiting to our west by Tuesday
morning...allowing mid/upper level ridging centered off the
Carolina coast to begin build overhead. Tuesday is shaping up to
be a transition day for the weekly weather pattern as drier air
aloft begins to migrate in from the south and southeast through
the day. Generally speaking...it does not appear as through the
driest air will arrive aloft in time to significantly decrease the
diurnal convective convective actively, and decent coverage of
storms after early afternoon should be expected within the favored
southeast synoptic low level flow.
Thereafter...through the remainder of the week...GFS/ECMWF in
agreement in several waves of drier air aloft becoming fixed over
the Florida Peninsula. Which days will see the driest of air vs
another day is tough to tell this far out...however...it is very
likely that the degree of dry air aloft will be a negative factor
toward convection through a good portion of the week. No way we
can remove rain chances all together during this time of
year...but dropping pops down below climo (especially for climo
during southeast flow) seems appropriate given the pattern aloft.
We are looking way out into the extended period...but increasing
moisture looks to return above our heads potentially during the
second half of next weekend.
Temperatures through the period look seasonable to a bit above
climo...especially during the day with the lesser coverage and
persistent surface high pressure over the northern Gulf of Mexico
will keep generally east to southeast winds in place over the
coastal waters through the next several days, except where winds
turn onshore near the coast with the afternoon sea breeze. Winds
and seas will generally remain light, although daily thunderstorms
will be capable of producing locally hazardous boating conditions.
relative humidity will remain well above critical levels through
the forecast period, with no significant fire weather concerns
Preliminary point temps/pops...
tpa 90 76 90 77 / 50 20 50 20
fmy 89 75 90 76 / 50 30 60 30
gif 92 73 92 75 / 50 30 50 30
srq 87 76 88 76 / 40 20 40 20
bkv 92 73 92 74 / 50 20 50 20
spg 90 77 91 79 / 40 20 40 20