Scientific Forecaster Discussion
fxus62 kjax 150144
Area forecast discussion
National Weather Service Jacksonville Florida
844 PM EST Sat Dec 14 2019
Weak sfc high pressure over the east and northeast Gulf of Mexico
will move in over the region through Sunday morning. Clear skies
and near calm winds, and recent rainfall will set up for some
very good conditions for radiation fog. Current forecast already
shows this and just adjusted fcst slightly to expand areas of fog
north and northeast. Some dense fog is expected at times roughly
from 4 am to 8 am Sunday morning. Widespread min temps in the 40s
No significant changes to the forecast. West to northwest winds
around 10-15 kt will turn toward the north-northwest by sunrise
and decrease gradually. Seas may be up to near 4-6 ft well
offshore but expected to drop off through early Sunday morning.
Thus, will continue with scec headline for the evening offshore
Previous discussion [637 PM est]...
Near term.../through tonight/...
..potential for significant fog overnight...
High pressure will build from the west this afternoon with skies
gradually clearing. The high will build overhead tonight. With low
level moisture in place from recent rains, and winds going light
under the ridge, expect fog formation overnight, which could become
dense. This trend will be monitored through the evening into
tonight, in the event an advisory may be needed for dense fog. Lows
tonight in the 40s expected.
Short term.../Sunday through Wednesday/...
Fog may linger for awhile into Sunday morning. High pressure will
be overhead Sunday morning, then move to the east Sunday
afternoon into night. High pressure will remain to the east
through Monday, then to the southeast Monday night. Dry weather is
expected for Sunday into Monday, with a moderating temperature
trend as the flow becomes more southerly. A cold front will move
southeast across the area Tuesday into Tuesday evening. A round of
showers with embedded thunderstorms expected with this boundary.
High pressure will then build from the west northwest through
Wednesday with rain ending and skies clearing.
Temperatures will trend above normal through Tuesday, then below
normal on Wednesday.
Long term.../Wednesday night through Saturday/...
..inland freeze Wednesday night...
High pressure will build to the north Wednesday night through
Thursday night, with onshore flow increasing, leading to the
potential for a few coastal showers over NE Florida. The high will move
to the northeast Friday into Friday night, as an inverted trough
develops along the Atlantic coast. This will increase the potential
for mainly coastal showers. This trough is then expected to
strengthen and move to the east on Saturday, as high pressure builds
from the west.
Temperatures will trend below normal into Thursday, then near to a
little above normal for Friday into Saturday. Freezing temperatures
will be common inland on Wednesday night.
[through 00z monday]
Light to calm winds tonight, and VFR through much of the night
though areas of fog likely to develop after 06z. Indicated IFR
vsby for vqq and gnv and MVFR vsby for jax and crg. Potential for
LIFR/vlifr right around the 10z-12z time frame but uncertain at
this time. Fog and any stratus to dissipate by 14z or shortly
thereafter with VFR rest of Sunday.
High pressure will build from the west through tonight. The high will
move to the east Sunday into Monday. The high will move to the
southeast Monday night as a cold front approaches from the
northwest. This front will cross the region Tuesday, with a round
of showers and storms. High pressure will build from the west
northwest Wednesday, then to the north on Thursday.
Rip currents: low risk on Sunday.
Preliminary point temps/pops...
Amg 41 64 47 76 61 / 0 0 0 0 20
ssi 46 62 53 72 61 / 0 0 0 0 10
jax 45 67 52 78 61 / 0 0 0 0 10
sgj 48 66 55 77 61 / 0 0 0 0 10
gnv 45 70 51 78 60 / 0 0 0 0 10
ocf 45 72 52 80 59 / 0 0 0 0 10