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fxus62 kjax 271548 
afdjax

Area forecast discussion
National Weather Service Jacksonville Florida
1148 am EDT Thu Apr 27 2017

..hot, breezy and dry conditions this afternoon...

Update...
late morning surface analysis depicts a cold front extending from
the Great Lakes states southward through the Tennessee Valley and
approaching the western Florida Panhandle. Aloft...shortwave
troughing is deflecting northeastward through the upper Midwest
and towards the western Great Lakes by ridging that is
strengthening over the Gulf of Mexico and South Florida. Our local
pressure gradient continues to tighten with the approach of the
cold front well to our west, with breezy southerly winds of 15-25
mph in place nearly area-wide as of 15z. A few patches of
stratocumulus are migrating across southeast Georgia, with the
deeper cumulus field building over the Florida Big Bend. Sunny
skies and rising heights aloft are resulting in skyrocketing
temperatures, as most locations are already in the low to mid 80s,
with dewpoints falling into the upper 50s and lower 60s. There are
no signs of the smoke plume from the ongoing west Mims wildfire as
of 1530z from visible satellite imagery nor kjax/kvax Doppler
radars.

The Atlantic coast sea breeze will struggle to move very far
inland this afternoon and should remain east of the Interstate 95
corridor later this afternoon. This will allow highs to climb to
the upper 80s at the beaches, with lower 90s expected inland. All
model guidance keeps convection associated with the weakening cold
just northwest of the Altamaha/Ocmulgee rivers this afternoon.
Strengthening winds will likely invigorate the west Mims
wildfire smoke plume this afternoon, with smoke likely impacting
Folkston and Nahunta, possibly reducing visibilities to 3-5 miles
at times. We expect a stratus deck to move onshore from the
northeastern Gulf of Mexico overnight, impacting the Suwannee
Valley and interior southeast Georgia during the predawn hours on
Friday. Deep south-southwest flow will result in warmer low
temperatures tonight, with mid to upper 60s forecast area-wide.

&&

Aviation...
VFR conditions will prevail at the regional terminals through at
least 06z. Southerly surface winds will continue to strengthen
this afternoon, with sustained speeds near 15 knots with frequent
gusts to 25 knots. Winds may back to a more southeasterly
direction after 18z at sgj and ssi as the Atlantic sea breeze
attempts to move inland. Smoke from the ongoing west Mims wildfire
may begin to impact ssi after 06z, with a low confidence in MVFR
visibilities at ssi during the predawn hours on Friday. A low
stratus deck is expected to move inland from the northeast Gulf of
Mexico overnight, with MVFR to IFR ceilings possible at gnv
towards 09z.

&&

Marine...
a cold front is slowing its forward progress as it moves into the
southeastern states, which is causing our local pressure gradient
to tighten. South-southeasterly winds will strengthen as the
afternoon progresses, and small craft should exercise caution in
both the near shore and offshore waters today as speeds increase
to 15-20 knots. Seas offshore will build to 4-5 feet by late
afternoon. The front will stall well to the northwest of the
waters this evening and will then lift northward as a warm front
on Friday, resulting in a loosening local pressure gradient as
the axis of Atlantic ridging begins to lift northward from the
Florida Peninsula. Winds will become south southwesterly this
evening, with speeds falling below caution level speeds in the
near shore waters. Winds will remain south-southeasterly through
Saturday, with caution level speeds continuing tonight offshore
and then remaining just below caution level speeds from Friday
through Saturday. The next cold front on the horizon will move
through the lower Mississippi Valley on Sunday, causing our local
pressure gradient to gradually tighten late this weekend.
Southerly winds will strengthen to caution levels on Saturday
night and will continue through Sunday night for both the near
shore and offshore waters. Winds and seas are expected to reach
Small Craft Advisory levels in the offshore waters on Monday as
the cold front approaches our waters from the west.

Rip currents: low risk expected today, with a moderate risk
possible from Friday through the weekend due to persistent south-
southeast winds combined with a southerly longshore current.



&&

Fire weather...
winds today will veer to the southwest and increase to 15 to 20
mph with gusts up to 25 to 30 mph. Relative humidities will bottom
out this afternoon mainly in the 30-40% range. Dispersions will be
high today, especially across inland southeast Georgia.

Hot and dry conditions will continue into Friday. Winds will be
lighter as high pressure ridge settles over the region, with
prevailing winds generally out of the southwest around 10 mph. The
seabreeze will push well inland late Friday afternoon with winds
becoming southeasterly and gusty behind the seabreeze, especially
near the coast. Relative humidities will climb a little but some
areas could still drop down into the 35-40% range. Although
chances are low, isolated thunderstorms will be possible as the
two seabreezes collide near the Highway 301 corridor late in the
day on Friday.

&&

Climate...

Record highs for today 4/27...
jax 94/1986...gnv 96/2011...amg 96/1986...ssi 94/1986

Record highs for tomorrow 4/28...
jax 94/1991...gnv 95/1991...amg 92/1970...ssi 92/1985

&&

Preliminary point temps/pops...
amg 89 66 92 68 / 10 10 10 10
ssi 84 71 86 72 / 0 0 10 10
jax 91 67 92 71 / 0 0 10 10
sgj 89 69 87 72 / 0 0 10 10
gnv 91 66 94 68 / 0 10 20 10
ocf 91 66 95 69 / 0 0 20 10

&&

Jax watches/warnings/advisories...
Florida...none.
Georgia...none.
Am...none.
&&

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