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Area forecast discussion 
National Weather Service Jacksonville Florida
420 am EDT Sat Aug 30 2014

Short term...

This morning...patchy fog is occurring early this morning over areas
that received heavy rain from the previous day. The visibility may
briefly get down to less than a quarter of a mile or less at times
in few spots especially near the I-75 corridor including
Gainesville. The fog will lift rapidly by middle morning.

Today/tonight...a mean layer (1000-500 mb) ridge will begin to
nudge just north of the area by late today. Light winds along
with deep layer moisture and heating will help produce scattered
storms area-wide by afternoon with best coverage across inland
areas as the Atlantic/Gomex sea breeze fronts move slowly inland. Maximum
temperatures again in the lower to middle 90s inland and a shade under 90
along the coast. The scattered thunderstorm activity is expected
to end during the evening with the loss of heating.

Sunday/Sunday night...mean layer ridge will be across south Georgia
and slowly retrograding. Light easterly steering flow along with
deep layer moisture and heating favors diurnal storms again
with best coverage across the inland areas and out towards the
I-75 corridor by late in the afternoon and early evening where the
merger of sea breezes and other outflows will occur. Maximum temperatures
again in the lower to middle 90s inland and a shade under 90 at
the coast. The scattered thunderstorm activity is expected
to end during the evening with the loss of heating.

Long term (from Monday through friday)...
little change in prior forecasts as models show 1000-500 mb ridge
just north of the area Monday and Tuesday resulting in deep layer east to NE
flow helping to push East Coast sea breeze inland easily each day. Maximum
temperatures will be above normal with 500 mb heights about 5915 meters.
Highs around middle 90s inland and lower 90s to near 90 toward the
coast. This fairly typical pattern for this time of year will favor
inland areas for precipitation chances around 30-40% range and 20-30% along
the coastal areas.

Mean flow begins to back late Tuesday into Wednesday as models show
well-defined middle and upper level low moving slowly northwest through the
Bahamas. A sliver of dry air in the middle levels well to the northwest of the
feature may inhibit convective showers and storms over our region on
Wednesday but for now due to uncertainty will indicate chance showers and
storms...should at least be 5-10% below normal.

Thursday and Friday...the GFS and European model (ecmwf) show the tropical upper tropospheric
trough (tutt) moving northward up the Florida Peninsula and advecting tropical
moisture into the forecast region by Friday from southeast to northwest. Lowering
heights and addition of moisture will help shave off a couple of
degrees from prior day high temperatures down to near normal during this
period. We should see rain chances increase for low chances on Thursday
to at least a 30-40% area-wide on Friday. Low level flow will
transition to more east and then southeast on Friday.


Aviation...patchy fog with occasional IFR at gnv until around 13z.
Scattered showers and thunderstorms expected across much of the
inland areas this afternoon with best coverage towards gnv. Have
thunderstorms in the vicinity at gnv beginning at 18z although amendments for possible IFR
due to ts possible at gnv between 18z-24z. Have thunderstorms in the vicinity at rest of NE
Florida terminals between 20z-24z. The scattered thunderstorm activity
will end during the evening with loss of heating and have vcsh at all NE
Florida terminals between 00z-03z. For ssi have prevailing VFR.


Marine...a ridge of high pressure will be just north of the waters
through much of the period. Winds mainly south or southeast 10
knots...slightly stronger during the evening but below headline
criteria. Seas generally 2 to 4 feet. Isolated showers and

Rip currents: a lingering east-southeast swell and afternoon onshore flow will
warrant a moderate risk of rip currents through the weekend.


Preliminary point temps/pops...
amg 95 72 94 72 / 40 30 40 30
ssi 88 77 89 77 / 20 20 30 20
jax 92 74 92 74 / 40 30 30 20
sgj 89 75 89 75 / 30 30 30 20
gnv 92 72 92 72 / 50 50 50 40
ocf 92 73 93 73 / 50 50 50 30


Jax watches/warnings/advisories...




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