Area Forecast Discussion
Issued by NWS Tampa Bay Area, FL
FXUS62 KTBW 231129
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
729 AM EDT SAT JUL 23 2016
Some patches of low clouds and fog will linger near KLAL through
13Z otherwise VFR will prevail through 18Z at all sites. After 18Z
brief MVFR/IFR conditions will be possible as scattered shra/tsra
develop over the region and have handled with VCTS for now.
Outside of the convection VFR will prevail. Light and variable
winds early this morning will become southeast to south at 6 to 8
knots after 15Z, except becoming southwest to west at all of the
coastal terminal sites after 18Z as the west coast sea breeze
develops. VFR will return to all terminals after 02Z tonight as
the convection winds down.
.Prev Discussion... /issued 341 AM EDT SAT JUL 23 2016/
SHORT TERM (TODAY - SUNDAY)...
Early morning water vapor satellite imagery is showing a large
circulation around an upper level ridge of high pressure over the
southeastern states and northern Gulf of Mexico, while an
elongated upper level trough off the east coast of the US is
bringing some drier air aloft into the east coast of Florida.
Through the rest of the weekend, this ridge will largely hold in
place, while the southern extent of the trough will break off as a
cut off low and drift west across the Florida Peninsula. This will
bring a somewhat drier atmospheric column into the area, with some
small amount of suppression to the thunderstorm activity. However,
moisture will remain abundant in the low levels, which combined
with strong surface heating will ensure scattered to numerous
thunderstorms will still develop each afternoon. The surface ridge
of high pressure is forecast to remain across northern Florida
through the weekend, keeping generally southeast winds in place.
This will favor a sea breeze collision over the western half of
the Florida Peninsula, and provide a focus for thunderstorms
during the late afternoon and early evening hours.
Temperatures will remain near 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 (Monday through next Friday)...
The long term portion of the forecast will start out on Monday
with an upper low feature that will reside over the FL peninsula
during the second half of the weekend...beginning to exit to our
west over the Gulf of Mexico. Throughout the day the influence of
this energy aloft will decrease. Throughout the remainder of the
forecast period...mid/upper level ridging will be in control of
our weather...with the ridge center slowly migrating from off the
Carolina coast during Tuesday...to a position over the northern
Florida peninsula by Friday.
At the surface...the subtropical ridge axis will remain in a general
position across the northern Florida peninsula...placing much of our
region within a zone of light to moderate east/southeast synoptic
low level flow. From a climatology standpoint...this flow is our
most convectively active wind regime related to the sea-breeze...and
the regime that produces the best potential for a few stronger
storms during the afternoon/evening. Of course that is climatology.
Subtle variations in mid-level moisture and low level wind speed can
have a big influence on how much storm coverage we see from day to
day. Unless the changes are large in scale (expansive swaths of
dry/moist air resolved well by all guidance members)...it is
difficult to predict these day to day variations all that far in
advance. So...for now...will keep our sensible weather forecast near
climo for the E/SE wind flow...with highest PoPs during the later
afternoon/early evening along the west coast of the FL peninsula.
Broad high pressure ridging across the northern Gulf of Mexico will
keep light and generally southerly to southeasterly winds in place
over the coastal waters through the next several days. Winds will
turn onshore near the coast each afternoon with the sea breeze.
Winds and seas will remain light through the start of next week,
except in the vicinity of thunderstorms where hazardous boating
conditions will be possible.
No fire weather concerns through the forecast period.
.Preliminary Point Temps/PoPs...
TPA 90 77 91 76 / 30 30 50 30
FMY 90 75 89 75 / 50 30 60 20
GIF 92 74 92 74 / 40 20 50 20
SRQ 89 76 89 76 / 40 20 50 30
BKV 92 72 92 72 / 30 20 40 30
SPG 90 78 90 78 / 30 30 40 30
SHORT TERM/AVIATION/MARINE/FIRE WEATHER...57/McMichael
MID TERM/LONG TERM/DECISION SUPPORT...99