Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Tampa Bay Ruskin Florida
241 PM EDT Sat Jul 4 2015
Short term (tonight - sunday)...
GOES water vapor satellite imagery shows a southern stream upper
level trough digging out of the Central Plains and into the lower
Mississippi River valley this afternoon. This feature will
continue to make slow progress into the southeastern states
through the rest of the weekend. At the surface...the subtropical
ridge axis is sitting just north of the Interstate 4 corridor
today...and will not move substantially through Sunday
night...setting up light southeasterly flow. This flow
pattern...combined with deep moisture of between 1.5 and 2 inches
of precipitable water...will result in scattered to numerous
thunderstorms developing over the land zones during the early
afternoon...intensifying over the interior and along the West
Coast during the middle to late afternoon...and then tapering off
through the early evening hours. With 500 mb temperatures
forecast to remain around -9 to -10c...the possibility for severe
hail...as well as gusty winds will continue on Sunday afternoon.
Long term (sunday night-saturday)...
high pressure will ridge over the state from the Atlantic through
the period with the ridge axis lifting north of the area Monday
and remaining north of the area through the rest of the period.
This will keep generally southeast flow in place with afternoon sea
breezes developing near the coast each day. Weak ridging will be
in place aloft through mid-next-week...then a TUTT low will move
over South Florida for Wednesday and Thursday lowering probability of precipitation just a
bit as some drier air moves over the area. Scattered afternoon
storms will still be possible each day. Temperatures will be in
the upper 80s/lower 90s each afternoon and in the 70s each
scattered thunderstorms have already developed across the area and
will continue to expand in coverage and threaten area terminals
through early this evening. Brief periods of IFR or LIFR conditions
are expected as storms pass nearby. VFR conditions will take hold
again by around 00z...until another round of thunderstorms spin up
early Sunday afternoon.
high pressure ridging over the coastal waters will keep winds
light and seas low through at least midweek. The only marine
concern will be locally higher winds and seas in the vicinity of
daily thunderstorms...along with frequent lightning strikes.
no significant fire weather issues expected for the next several
Preliminary point temps/pops...
tpa 93 78 92 78 / 50 10 50 20
fmy 93 75 93 75 / 60 20 50 20
gif 95 75 94 75 / 60 30 60 20
srq 92 76 91 76 / 30 10 50 20
bkv 95 73 93 72 / 50 20 60 20
spg 92 79 92 80 / 30 10 50 20
Short term/aviation/marine/fire weather...18/Fleming