Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Jacksonville Florida
317 PM EDT Friday Mar 27 2015
..showers and scattered thunderstorms eastern counties rest of
today due to a cold frontal passage...
..much cooler this weekend...
Short term...showers and isolated to scattered storms will continue
to fire and develop ahead of the cold front now located from
Jesup to Lake City. Main threats will be brief heavy rainfall...
lightning...and gusty winds. Storm Prediction Center has put our eastern zones and southeast
sections in a marginal risk with the main concerns gusty winds.
Latest laps cape analysis shows SBCAPE of 500-1000 j/kg. The
threat of any isolated strong storms should end this evening.
Tonight/Saturday...skies will be clearing from northwest to southeast as the
front moves southeastward and high pressure builds in from the northwest.
Mostly clear conds on Saturday. Much colder air will work into
the region tonight with lows in the Lower/Middle 40s inland with
upper 40s/around 50 coast. With winds staying up around 5-10 miles per hour
by early morning...wind chill readings will fall into the 30s for
most areas. The chill will persist Saturday with highs in the
Lower/Middle 60s for most areas...with only minor changes from the
prior forecast. Will be breezy Saturday with northwest winds around 15 miles per hour
with gusts around 25 miles per hour.
Long term...(sunday through thursday)...a broad upper level
trough along the eastern Seaboard begins to lift out of the area
with the next short wave trough and cold front moving in Monday
night into Tuesday. Might see a line of showers associated with
the front Monday night. This system will be replaced by a zonal
flow pattern with a developing short wave/low over the upper Gulf
Coast on Wednesday. This short wave advances east on Thursday
bringing our next chance of rain. Overall temperatures looking to start
out below normal on Sunday and Monday and be near or slightly
above normal later next week.
Aviation...MVFR to low end VFR ceilings conditions continue this
afternoon with a good chance of MVFR conditions being realized in
convective activity. Can't rule out a brief IFR conditions here in
the next 2-3 hours in storms. Already seen one observation show 2sm
in a thunderstorm so remains a possibility this afternoon. Convective
activity will move out this evening and clear skies and west to northwest
winds expected around 10-15 knots...settling down to 5-10 knots late
tonight though a few gusts to 20 knots possible. Winds increase from
the northwest around 10-12g20kt Sat and VFR prevails.
Marine...winds are S to SW around 15 knots offshore and 10-15 knots
nearshore per latest rtma analyses. Seas 2-4 feet. Flow veers to
the northwest as the frontal boundary crosses the waters this
evening. Marginal Small Craft Advisory continues for the offshore waters this afternoon
but winds and seas increase tonight through early Saturday.
High pressure builds in behind the front with winds/seas
gradually decreasing Sunday into early next week.
Rip currents: low risk through Sat due to offshore flow.
Preliminary point temps/pops...
amg 40 60 37 64 / 10 0 0 0
ssi 46 62 43 62 / 10 0 0 0
jax 43 65 44 63 / 10 0 0 0
sgj 47 64 48 64 / 10 0 0 0
gnv 44 66 40 67 / 10 0 0 0
ocf 46 68 41 68 / 10 0 0 0
Am...Small Craft Advisory until 5 PM EDT Saturday for waters from
Altamaha Sound Georgia to Fernandina Beach Florida from 20 to 60 nm-
waters from Fernandina Beach to St. Augustine Florida from 20 to
60 nm-waters from St. Augustine to Flagler Beach Florida from 20
to 60 nm.
Small Craft Advisory from 6 PM this evening to 6 am EDT Saturday
for coastal waters from Altamaha Sound to Fernandina Beach
Florida out 20 nm-coastal waters from Fernandina Beach to St.
Augustine Florida out 20 nm-coastal waters from St. Augustine to
Flagler Beach Florida out 20 nm.