Scientific Forecaster Discussion
fxus62 ktbw 201147
Area forecast discussion
National Weather Service Tampa Bay Ruskin Florida
747 am EDT sun Aug 20 2017
VFR conditions can be expected through this morning. Some
brief MVFR/IFR conditions will be possible this afternoon
with passing storms after 18z. Will keep overall VFR
conditions in tafs for now and cover with thunderstorms in the vicinity and tempo
groups later in the day based on radar coverage. No other
aviation impacts expected.
Prev discussion... /issued 401 am EDT sun Aug 20 2017/
Short term (today - monday)...
upper low spinning in southeast Gulf this morning to move further
into the central Gulf through Sunday. Deep tropical moisture
advecting over the area pulled into the Gulf low today then
dry pocket in mid-upper levels to move over the area Monday.
Weak tropical wave at the surface along the Southeast Florida coast this
morning to move over the Florida Peninsula today during Max
heating to collide with Gulf seabreeze for numerous
thunderstorms in SW Florida building into the Suncoast late this
afternoon with mainly scattered convection from the Bay
area into the Nature Coast with around normal warm and humid
conditions. Monday, expect hot temps with muggy humidly and
mainly isolated late afternoon storms as temps soar into
the mid+ 90s and heat index 105-108.
Middle term/long term (monday night-saturday)...
some mid/upper level ridging will be across the region into midweek
then global models bring a wave westward into Florida which gets
picked up by a trough moving across the eastern U.S. Late in the
week. This pattern will bring an area of drier air across the region
Monday night and early Tuesday followed by an increase in deep
moisture for the rest of the week. Therefore, other than some low
rain chances, less than 30 percent, north of about the Interstate 4
corridor Tuesday, the rain chances look to be pretty high through
much of the period with 40 percent north to 70 percent south
Wednesday, then 60 to 70 percent everywhere for Thursday through
Saturday. Convection will occur mainly during the afternoon and
evening hours, but as we head toward the end of the week a more
south to southwest flow will setup so morning convection will become
possible near the coast.
Daytime high temperatures will remain near normal to slightly above
normal through Wednesday, then near to slightly below normal for the
rest of the week thanks to more clouds and higher rain chances.
Overnight lows will remain near to slightly above normal through the
increased moisture today will bring better chances of
afternoon thunderstorms will keep thunderstorms in the vicinity in all sites from
16z-18z through 00z-02z expect brief MVFR/local IFR conditions
in stronger storms.
weak high pressure in place and a weak tropical wave will
move over the East Gulf today with scattered to numerous
afternoon thunderstorms possible. High pressure then remains
north of the waters through midweek as a couple of troughs
move across Florida and out over the Gulf. The ridge begins to
settles south toward the end of the week. Winds to remain
mainly light and slight seas except in or near
warm and humid summertime conditions continue with daily rain
chances through early next week.
Preliminary point temps/pops...
tpa 92 79 94 78 / 60 30 20 10
fmy 90 76 94 76 / 60 30 20 10
gif 92 76 94 75 / 50 20 20 10
srq 91 78 94 77 / 60 30 20 10
bkv 93 76 94 74 / 40 20 30 10
spg 92 80 93 78 / 60 30 20 20