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Area forecast discussion 
National Weather Service Melbourne Florida
800 PM EST Wednesday Feb 10 2016

Discussion...

..near record lows forecast overnight...
..Freeze warning North Lake/Volusia counties 3am-9am Thursday morning...
..frost advisory for remainder of east central Florida 3am-9am Thursday
morning...

Updated zones and coastal waters forecasts to remove expired headlines

Current...infrared satellite imagery loops shows some cirrus associated
with the departing 250mb jet maximum moving east and away from central
Florida. Mostly clear to clear skies by late evening. Temperatures
should drop quickly from radiational cooling through middle/late
evening. Lowest layer(s) decouple after midnight. This allows winds
to become light to calm. 18z guidance a degree off forecast mins.
Forecast in good shape. Freshen wording.

Aviation...VFR.

Marine...buoy 009 was recording west wind 21 to 27 knots and 6 foot
seas. Continue exercise caution out to 20nm and Small Craft Advisory
beyond 20nm.

Climate...record lows for Thursday, 11-Feb below:

Low-min
dab 11-Feb 30 1971
mco 11-Feb 29 1947
mlb 11-Feb 32 1973
vrb 11-Feb 35 1974

Previous afd issued 300 PM EST Wednesday Feb 10 2016



Current-tonight...cool/breezy over much of
east central Florida this afternoon. High cloudiness gradually
decreasing from north to south as upper jet slowly exits the area
late today. High pressure over the Gomex will slowly slide eastward
tonight with center near the area. This will allow for skies to
continue to clear with west-northwest winds becoming light. The very cool/dry
airmass in place will allow for temperatures after sunset to drop
rapidly this evening.

Will hoist a freeze warning for late tonight for North Lake/Volusia
counties. With this would expect temperatures between 29 and 32
degrees for at least two hours late overnight/early Thursday morning.
Elsewhere...overnight mins expected in the l-m30s throughout ecfl.
Barrier islands may stay a few degrees higher than these numbers.
The warmest areas metropolitan Orlando and immediate St. Lucie/Martin
coasts will probably realize around u30s. Will also issue a frost
advisory for areas of frost southward from the freeze warning across
the coverage warning area.

Thursday...cold start to the morning with near freezing temperatures
around and areas of frost. High pressure across the region will
result in a weaker pressure gradient and light winds. Conditions
will remain dry. Afternoon highs will manage back into the l60s
perhaps a few m60s around... lows for Thursday, 11-Feb below:



Thursday night-Friday...surface high center will shift south toward Okeechobee
County late Thursday night with lows around 40 for Okeechobee County and
inland sections of the Treasure Coast. Light SW flow north of the
ridge may hold temperatures up a few degrees...but still in the 40s for metropolitan
Orlando and Volusia County. Surface ridge will remain near Okeechobee
and Martin counties Friday with a warmer westerly flow expected over
much of the area for the afternoon. Should see highs closet to
seasonal norms in the Lower-Middle 70s under mostly sunny skies.

Modified previous discussion... Sat-Tue... progressive weather
pattern into early next week as a 140-160kt jet streak over the
central/western Pacific plows its way into the eastern Pacific/western Continental U.S.. troffing
pattern over the eastern Continental U.S. Early Sat will eject northeastward into the northwest
Atlantic over the weekend...followed by a second trough that will form
over the upper Midwest/Great Lakes region by daybreak Monday as the Pacific
jet pushes its the ascending left exit quadrant across the central Continental U.S..

Back door front with attendant nearly wind surge will push into
central Florida on sun but will stall and wash out late Sun night as hi
pressure over the eastern Seaboard builds offshore and winds veer to the
E/se. Weak cold air advection Sat/sun as winds veer from north/northwest to NE...but less than
10f below average. Deepening onshore flow will erode the subsidence
inversion through the h100-850 mb layer and may allow a few coastal rain showers to
develop showers Sun night. Rain showers chances increases and may spread inland Monday
as winds veer more to east or southeast ahead of the next cold front. The
10/00z GFS/European model (ecmwf) runs continue in general agreement with a frontal passage early
next week...but are leaning more toward this occurring during the
day Tuesday.

&&

Aviation...VFR. Breezy west-northwest winds will decrease around sunset and
fall to light this evening/overnight. High pressure will build
eastward from the Gomex to across the area over the next 24hrs
relaxing the pressure gradient. Light northwest morning winds Thursday becoming
l/v interior and light nerly space/Treasure coasts.

&&

Marine...tonight-Thu...Small Craft Advisory remains in place
offshore through 09z/4am Thursday. Surface high pressure over the Gomex
will build eastward to across the coastal waters over the next
24hrs. Gusty west-northwest winds will decrease this evening/overnight becoming
more nwrly into early on Thursday. Wind speeds will fall to less than 10
kts from middle to late Thursday afternoon. Seas 3-5 feet near shore and 5-8
feet offshore will continue to decrease through the period to 3-4 feet
by daybreak Thursday morning near shore and 5 feet offshore...continuing to
subside to 2-3 feet near shore and 4 feet offshore by late Thursday afternoon.

Thursday night-Friday night...surface high pressure will shift from Lake
Okeechobee to S Florida into late week with increasing westerly flow
north of the ridge axis and ahead of another frontal boundary
dropping southeast off the southeast Atlantic coast. SW/west flow will increase initially
north of the volume-Brevard line on Friday and increase north of
Sebastian Inlet from the west to 15-20 knots Friday night. Highest seas
up to 5 feet across the well offshore waters.

Sat-Mon...a dry front will move south across the waters Sat
increasing the northwest/north winds to 15-20 knots. Flow will veer to the NE
Sat night and onshore Sunday to 15-20 knots with advisory conditions
expected for much of the waters. Veering winds to southeast Monday should
weaken some with an increasing coverage of showers and seas 4-6 feet.

&&

Fire weather...remainder of afternoon-tonight...gusty west/west-northwest winds
will fall to light this evening/overnight as high pressure builds
eastward across the area from the Gomex. Low min rh's areawide range
from the 20s to l30s with very dry/cool airmass in place. Freeze
warning for North Lake/Volusia counties late tonight/early Thursday
morning with areas of frost forecast. Southward from here a frost
advisory will be in place...again with areas of frost forecast.

Thursday...poor to fair dispersion as a hi pressure ridge builds over central
Florida...allowing transport winds to diminish while reducing mixing
heights to less than 3kft. Overall fire threat will remain
low...however...as erc values are expected to remain in the l/M
teens. Diminishing winds will reduce overall fire threat.

Friday...min rhs into the middle 30s and gusty west winds in the afternoon
will cause a fire weather sensitive day...but ercs are expected to remain
low with no headlines anticipated.

&&

Climate...record lows for Thursday, 11-Feb below:

Low-min
dab 11-Feb 30 1971
mco 11-Feb 29 1947
mlb 11-Feb 32 1973
vrb 11-Feb 35 1974

&&

Preliminary point temps/pops...
dab 33 61 45 73 / 0 0 0 0
mco 37 64 45 75 / 0 0 0 0
mlb 33 63 42 73 / 0 0 0 0
vrb 34 63 41 72 / 0 0 0 0
Lee 35 64 48 74 / 0 0 0 0
sfb 35 63 46 74 / 0 0 0 0
orl 39 64 48 74 / 0 0 0 0
fpr 37 64 42 73 / 0 0 0 0

&&

Mlb watches/warnings/advisories...
Florida...frost advisory from 3 am to 9 am EST Thursday for Indian River-
Martin-northern Brevard County-Okeechobee-Orange-Osceola-
Seminole-southern Brevard County-Southern Lake County-St.
Lucie.

Freeze warning from 3 am to 9 am EST Thursday for coastal
Volusia County-inland Volusia County-Northern Lake County.

Am...Small Craft Advisory until 4 am EST Thursday for Flagler Beach
to Volusia-Brevard County line 20-60 nm-Sebastian Inlet to
Jupiter Inlet 20-60 nm-Volusia-Brevard County line to
Sebastian Inlet 20-60 nm.

&&

$$

Impact weather...pendergrast
forecasts...Wimmer

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