Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Tampa Bay Ruskin Florida
420 am EDT Sat Jul 26 2014
Short term (today-tonight)...
high pressure surface and aloft will hold over west central and
southwest Florida through tonight. The surface ridge axis will
remain south of the forecast area which will allow west to
southwest flow off the Gulf of Mexico. This will create very muggy
conditions across the area. An u/l low over the southeast Gulf of
Mexico will enhance u/l diffluence over the region increasing
convective instability. Pocket of cold air aloft will also hold
over the area through the day. Scattered showers and thunderstorms
will develop this morning over the coastal counties...and will
push inland and increase in areal coverage during the afternoon.
Locally heavy rain will occur with thunderstorms with the best
chance over the interior.
Middle term (sunday-monday)...
middle/upper level trough will deepen over the eastern U.S. With the
associated cold front diving into the deep south during Monday. This
will suppress the low level ridge even further south keeping a
southwest to west flow across the region. The deep moisture will be
pushed off to the east with some drier air moving in during Sunday
and Monday...however as the front approaches from the north the
northern portions of the area will see moisture return Monday
afternoon. We will still see isolated to scattered showers and
thunderstorms during the period with the convection over the coastal
waters and near the coast late at night into the morning hours then
shifting/developing inland each afternoon and evening. Best rain
chances will be over the interior Sunday and across the far north
Monday. Temperatures will be near normal with daytime highs in the
upper 80s near the coast to the middle 90s inland with overnight lows
Sunday night mostly in the middle to upper 70s...but some coastal areas
will only fall into the lower 80s thanks to the onshore flow.
Long term (monday night-friday)...
the middle/upper level troughing will linger over the eastern U.S.
Through the week with the models pushing the cold front all the way
south into north central Florida during midweek as a weak area of
low pressure forms along the boundary over the eastern Gulf. This
setup will keep a westerly flow across the region through midweek
then winds should become rather light and variable late in the week
as the boundary settles over the region and gradually dissipates.
Deep moisture associated with the boundary will stretch across the
area and with a series of shortwaves moving through the middle/upper
level trough we should see at least scattered convection each day.
The timing of these shortwaves will determine the exact timing and
amount of convection that develops...but either way it looks to be
somewhat mostly cloudy with a chance of rain at almost anytime
through most of the period. Temperatures will range from lows mostly
in the 70s to highs in the upper 80s to lower 90s through the period.
VFR conditions will prevail...with local MVFR ceilings and MVFR/IFR visibilities
associated with thunderstorms. Best chance of thunderstorms vicinity
tpa/pie/srq will be between 12z and 18z...vicinity lal 17-22z...and
vicinity pgd/fmy/rsw 16-22z.
scattered late night early morning showers and thunderstorms will
occur over the coastal waters this morning...and again tonight.
Winds will remain less than 15 knots with seas less than 4 feet
through the period.
abundant low level moisture will keep relative humidity values well
above critical levels through the period. No fire weather hazards
Preliminary point temps/pops...
tpa 91 78 92 79 / 40 20 20 20
fmy 92 78 93 76 / 30 20 30 20
gif 93 76 94 75 / 60 20 30 20
srq 91 79 92 78 / 40 20 20 20
bkv 91 74 94 74 / 30 20 20 20
spg 90 82 90 81 / 40 20 20 20
Short term/aviation/marine/fire weather...13/Oglesby
middle term/long term...69/close