Scientific Forecaster Discussion
fxus62 ktbw 191829
Area forecast discussion
National Weather Service Tampa Bay Ruskin Florida
229 PM EDT Thu Apr 19 2018
Short term (tonight-friday)...
fairly benign weather through Friday with upper trough over
New England and ridging through the plains states producing
near zonal flow aloft. Surface dry frontal boundary slowly
sinking through the deep south this afternoon into North Florida peninsula
tonight before stalling and beginning to wash out over c Florida
Friday. Weak SW low level flow over the area this afternoon
and evening to veer NE overnight and Friday as high pressure
bridges into the region Friday. Only impact from front is expected
to be partly cloudy skies tonight with patchy fog developing
overnight some fog may be locally dense in typical fog prone
areas, otherwise low temps around seasonal normal values. Dry
conditions continue Friday with upper shortwave moving along
the north Gulf Coast region and surface high pressure from the
Great Lakes through the southeast U.S. With northeast surface winds
with daytime temps remaining close to normal.
Long term (friday night -thursday)...
at the start of the period a weakening cool front across the Central
Peninsula will become diffused as surface high pressure along the
mid Atlantic coast bridges across its remains with a slight uptick
in northeast winds expected across the region under partly cloudy
skies. As we move into the upcoming weekend and into the first part
of next week a period of unsettled weather is shaping up as an upper
level trough/closed low and attendant surface low pressure moves
across the deep south. An easterly wind flow on Saturday becoming
southeast to south on Sunday will allow for a slow increase in
moisture across the region which will support low chances (pops 20
to 40 percent) for some low topped showers on Saturday, with rain
chances then increasing into the 50 to 70 percent range during
Sunday and Monday with chances for showers and storms as even deeper
moisture (pw's rising into the 1.5-1.7 inch range) is pulled into
the area ahead of cold front which will approaching from the west.
During Monday night into Tuesday rain chances will remain elevated
as the cold front moves slowly south through the region with weak
areas of low pressure moving along it as the upper level trough and
parent low pressure area moves northeastward up along the mid
Atlantic coast. On Wednesday some lingering moisture across southern
sections may fuel a few afternoon showers during the afternoon,
otherwise drier conditions are expected across the remainder of the
forecast area. During late Wednesday night into early Thursday a
short wave trough moving through the eastern U.S.Upper level trough
will help to pull a secondary cool front south through the region.
Limited moisture along and ahead of this boundary should result in a
dry passage with just a wind shift into the northwest and north
expected in its wake as surface high pressure builds in over the
Gulf and Florida in its wake during Thursday night into Friday.
Near to slightly above normal temperatures at the start of the
period will be tempered some during early next week as clouds and
rain chances increase across the region with readings in the lower
to mid 80s during the weekend falling back into the upper 70s to
lower 80s Monday and Tuesday, before returning to near seasonal
levels during Wednesday and Thursday.
vrf conditions this afternoon through this evening with westerly
winds becoming light. Overnight expect patchy fog to develop
along with lingering smoke for MVFR vsby/cigs and fog prone areas
may see locally IFR conditions through around 12z. VFR conditions
returning Friday mid morning.
weak cold front to wash out over the East Gulf waters tonight and
Friday. High pressure to build into the region with tightening
pressure gradient to increase NE winds and seas Friday evening
through the week. May see brief scec-Small Craft Advisory conditions especially
through the evening surge timeframe. Early next week a cold
front will approach from the north with southerly winds shifting
fairly dry conditions to continue over the area with min rhs
bottoming out in the mid 30% range especially over inland areas
south of the Interstate 4 corridor Friday afternoon. Low level
moisture and rhs will slowly increase through the weekend with
occasionally gusty NE-east winds.
Preliminary point temps/pops...
tpa 67 81 67 83 / 0 10 10 30
fmy 65 85 69 86 / 0 0 10 20
gif 63 83 67 82 / 0 0 30 40
srq 66 77 68 82 / 0 0 0 30
bkv 61 78 64 81 / 10 10 10 20
spg 67 82 69 82 / 0 0 0 20