Area Forecast Discussion
Issued by NWS Tampa Bay Area, FL
FXUS62 KTBW 030818
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
318 AM EST Sat Dec 3 2016
.SHORT TERM (Today-Sunday)...
Active pattern expected to develop across the southern tier of
the U.S. next couple of days, however a strong U/L ridge will
persist over the Florida peninsula and Caribbean through Sunday.
This will prevent any shower/thunderstorm activity from sinking
south over the region over the next couple of days. This will
allow dry warm conditions to persist across the forecast area
through the short term period.
Upstream, split flow U/L pattern will enter the west coast of the
U.S. with strong southern stream flow digging into the base of a
trough over the southwest U.S., with an U/L low cutting-off near
Baja California today and tonight. Northern stream trough and
associated S/W disturbance will push across the northern/central
plains today and tonight, and the Upper Mississippi Valley and
midwest on Sunday. U/L southern stream energy will eject across the
southern Plains today and over the Lower Mississippi Valley tonight
riding over a strong baroclinic zone with showers and thunderstorms
developing. The U/L energy will shear out over the southeast U.S. on
Sunday as it moves into confluent U/L flow. The cut-off low near
baja will gradually push east and approach the southern Plains late
.LONG TERM (Sunday Night - Friday)...
At the start of the period a cutoff upper level low over northern
Mexico will be lifting northeast toward Texas as an upstream upper
level trough amplifies over the northern Rockies. As this upper
low lifts out to the northeast surface cyclogenesis is expected to
take place along the southeast Texas coast along a quasi-
stationary front along the Gulf coast with this low then expected
to move northeast through the lower Mississippi valley on Monday
and into the Ohio Valley on Tuesday. As this storm system lifts
out to the northeast a trailing cold front from it will move east
across the eastern Gulf waters Monday night, and then through the
forecast area on Tuesday. Increasing moisture within the warm
sector ahead of the front will lead to increasing cloudiness and
rain chances for the entire forecast area Monday through Tuesday
as the front affects the region.
During Tuesday night into Wednesday the front will stall out across
the southern peninsula as it becomes parallel to the upper level
flow as weak high pressure builds in from the north with mainly dry
weather expected across central and northern zones, with a slight
chance of showers (pops 20 percent) continuing across the far south
in the vicinity of the stalled front.
By late in the week differences in the models continue with regard
to the evolution and speed of a developing long wave trough and
attendant cold front forecast to affect the region. At the moment
the GFS continues to be faster than the ECMWF with the eastward
progression of the trough and front with the GFS pushing the cold
front south through the region during Thursday and Thursday night
with another round of showers along and ahead of it, while the Euro
depicts weak surface low development on the front Thursday night
with the frontal passage taking place early on Friday. Given these
differences will stay fairly close to the previous forecast with
regards to rain chances and will wait to see if better model
continuity develops in the coming days. Temperatures will run some 8
to 10 degrees above normal through early Wednesday with more
uncertainty in temperatures developing late in the week due to the
timing of the front and the flip-flopping of the models with regards
to hold strong the cold air advection will be in the wake of the
front. In any event it does look as though much cooler and drier
conditions will be on tap for next weekend.
VFR conditions expected at all terminals for the next 24 hours
with skies predominately few/sct250.
Exercise conditions expected this morning over portions of the
outer waters today and tonight, with winds just below SCEC levels
on the near shore waters including Tampa Bay and Charlotte Harbor.
Winds may approach SCA conditions tonight over the outer waters.
Gradient will remain borderline for SCEC conditions over the next
couple of days, with possible SCA conditions Monday night and
Tuesday as an area of low pressure develops over the Lower
Mississippi Valley and lifts rapidly northeast. Gradient will
collapse late Tuesday and Tuesday night as weak high pressure
builds over the waters in the wake of the low pressure system.
No fire weather hazards expected through Sunday as there will be
sufficient low level moisture to keep minimum relative humidity
values above critical levels each day.
.Preliminary Point Temps/PoPs...
TPA 77 63 80 68 / 0 0 0 10
FMY 80 64 81 68 / 0 0 0 10
GIF 76 61 79 65 / 0 0 0 10
SRQ 77 63 79 68 / 0 0 0 10
BKV 76 59 80 65 / 0 0 0 10
SPG 76 64 78 68 / 0 0 0 10
FL...Beach Hazards Statement through Monday evening for Coastal
SHORT TERM/AVIATION/MARINE/FIRE WEATHER...13/Oglesby
MID TERM/LONG TERM/DECISION SUPPORT...57/McMichael