Area Forecast Discussion
Issued by NWS Tampa Bay Area, FL
FXUS62 KTBW 280726
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
326 AM EDT SUN AUG 28 2016
.SHORT TERM (Today and Monday)...
Upper troughing continues to dominate the northern and western
CONUS, with weak ridging extending across the Western Atlantic and
into the Mid-Atlantic and Southeast U.S. Along the southern
periphery of this ridge, several weak tropical disturbances
continue to drift westward. One such disturbance near Cuba will be
the primary weather maker over the next couple of days.
For today, expect a similar convective evolution as we have seen
over the last two days. However, models indicate some slightly
drier mid level air may mix down from the north. This may limit
shower and thunderstorm coverage overall, and will reflect that
with only chance PoPs through the afternoon. Showers are already
in progress across the Florida east coast. As destabilization
occurs by late morning and early afternoon, expect this activity
to expand inland and move westward through the evening. Gusty
winds and heavy rain will accompany any stronger storms that
manage to develop today, though they may be more sparse than
yesterday with the mid level drying.
From tonight into Monday, we will continue to monitor the
tropical disturbance near Cuba as it slowly moves northwestward
through the Florida Straits and into the southeastern Gulf of
Mexico by early Monday. Due to some lingering dry air and modest
wind shear, conditions do not appear conducive to rapid
development of this system, and any strengthening will be slow to
occur. Still, the presence of a weak area of low pressure in the
southeastern Gulf of Mexico will bring about southeasterly flow
across the Florida peninsula, which tends to be a wetter pattern
in general for west- central and southwest Florida. This will lead
to greater rain chances for Monday, especially along and south of
the I-4 corridor nearer the deeper tropical moisture. Again, any
heaver showers or stronger storms may produce gusty winds and
locally heavy rainfall/minor flooding will be a concern.
Conditions do look to become more favorable for tropical
development beyond Monday, and the system will need to be closely
monitored into early next week.
.MID/LONG TERM (Monday night-Saturday)...
A low pressure center in the vicinity of Dry Tortugas National
Park MON night slowly drifts northward over the central or eastern
Gulf of Mexico through midweek. During the latter part of the week
the low approaches the central or eastern gulf coast then takes a
northerly or northeasterly trajectory. Atlantic high pressure
begins to build west...between the Keys and Cuba on FRI.
The models initially are in fairly good agreement but diverge
through the week. However they all maintain deep tropical moisture
with PWAT values in excess of 2 inches. This will support
scattered to numerous showers with isolated to scattered
thunderstorms... resulting in heavy rainfall and the possibility
of localized flooding. Winds will increase especially on the Gulf
and some caution or advisory headlines are likely. The rainfall
and clouds will help keep highs running below normal while the
lows stay on the warm side due to the cloud cover. With much
uncertainty in the future of this system residents are advised to
use the most current forecasts.
.AVIATION (06z TAFs)...
VFR conditions to prevail at terminals overnight. Low chance of
some patchy low cigs at KFMY/KRSW/KPGD, but will not mention in
this forecast as any impacts will be brief. Much like yesterday,
expect to see sct SHRA/TSRA develop by 15z and move westward
through 00z, affecting most any terminal with gusty winds and
brief impacts to vsbys. Most activity will shift offshore by 01z
Monday, though some lingering SHRA may continue from KPGD south.
Breezy east to northeast winds will continue over the waters over
the next couple of nights as high pressure remains north of the
region and a tropical disturbance passes through the Florida Keys.
As the gradient tightens between these two features, at period of
cautionary to borderlined advisory level winds appears probable
tonight into Monday morning. Thereafter, the forecast is highly
uncertain and will depend largely on the path and intensity of the
tropical wave as it lifts into the central and eastern Gulf of
Mexico. For now, will keep winds in the 10 to 15 knot range,
becoming southeasterly through mid to late week. Regardless, the
prolonged breezy conditions will lead to increased seas of 3 to 5
feet, with the potential for even higher seas heading into the
latter half of the week. Rounds of marine thunderstorms will be
possible throughout the period, with greater chances during the
evening and overnight hours, and in the vicinity of the tropical
wave as it meanders over the Gulf.
With a warm and moist summer-like airmass in place, humidities
will remain well above critical levels, and no fire weather
concerns are expected.
.Preliminary Point Temps/PoPs...
TPA 93 77 91 77 / 50 10 60 30
FMY 92 76 88 77 / 50 30 70 50
GIF 93 75 91 75 / 40 10 60 20
SRQ 93 76 92 77 / 50 10 60 40
BKV 93 75 92 75 / 40 10 50 30
SPG 92 78 91 79 / 50 10 60 40
SHORT TERM/AVIATION/MARINE/FIRE WEATHER...84/Austin
MID TERM/LONG TERM/DECISION SUPPORT...09/Rude