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000 
FXUS62 KMLB 252146 RRA
AFDMLB

Area Forecast Discussion...Retransmission 
National Weather Service Melbourne FL 
445 PM EST Sat Feb 25 2017

.DISCUSSION...

Tonight...Diurnal clouds will dissipate for the most part post-
sunset, leading to mostly clear skies. Increasing boundary layer 
flow will preclude fog formation tonight, with the frontal wind 
shift and probably a modest (at best) increase in low-mid clouds 
reaching the northern CWA around midnight, Melbourne-Lake Kissimmee 
by 300 AM and Tequesta-central Lake Okeechobee between 500-600 AM.
CAA ushered in by the post-frontal northerly wind surge will drop 
temps through the 50s over all but the SE CWA, where some L60s will 
hang on. L50s should be confined from about I-4 northward.

Sunday...Sunny across most of the CWA with some lingering moisture 
indicated over the far SE CWA possibly leading to partly cloudy 
skies there. Highs ranging from the U60s Volusia coast to U70s south 
interior under NE winds of around 15 MPH and gusty, especially near 
the Atlantic coast.

Sunday Night...A fairly stout post frontal high pres ridge centered 
over the TX coast is embedded within a deep and strong mid/upr lvl 
zonal wind field that will carry it acrs central and north FL Sun 
night, into the W Atlc on Mon, then E of Bermuda by late Tue. Rapid 
motion of the ridge will prevent the incoming frontal trof from 
pushing much further south that the Gold Coast/S FL peninsula. 
Motion of the ridge will allow H100-H70 flow to veer from E/NE at 
sunset Sunday to E/SE by daybreak Monday.

Moisture will gradually pool within the frontal trof as it stalls 
over the south peninsula. As the return flow develops Sun night, 
this moisture band will work its way back into central FL. PWat 
values will remain too low for mentionable PoPs from North 
Brevard/Osceola Co. northward, but Treasure Coast/Lake-O PWat 
values, given their closer proximity to the trof/moisture band, will 
see PWat values increase from 0.75"-1.00" to 1.00-1.25" by daybreak 
Mon, most of which will be concentrated in the H100-H70 lyr. Add in 
a fairly brisk onshore flow (15-20KTS thru the H100-H70 lyr) and the 
potential for isold coastal shras cannot be ruled out. Mid/upr lvl 
dynamic support will be limited given the suppressive nature of the 
dominant ridge, any precip will in the form of low-topped shras with 
limited QPF. 

Onshore flow will rapidly modify any cool air that manages to push 
into central FL by daybreak Mon. Min temps will range from the 
M/U50s along and north of the I-4 Corridor to the M/U60s along the 
Treasure coast. 

Monday-Tuesday...Trailing ridge axis will remain draped over the 
central peninsula thru Tue. H100-H70 winds will veer to S/SE as a 
weak storm system dvlps over the nation's midsection and pulls a new 
cold front into Mid/Deep South. Slgt chc PoPs will cont areawide on 
Mon as the remnant frontal moisture band lifts back to the north 
under the influence of the SE flow. Precip chances will diminish Mon 
night into Tue as the H100-H70 flow night becomes increasingly 
parallel to the east FL coast. Precip chances will be limited to the 
Treasure Coast/Lake-O region...again in the form of low-topped shras 
as anticyclonic flow continues to dominate the lcl WX pattern, 
blocking out any meaningful mid/upr lvl dynamic support. 

Warm air advection will occur with the prevailing SE flow...pushing 
temps back abv climo avg. Max temps U70s/L80s on Mon, warming into 
the L/M80s on Tue. Min temps M/U60s both days. 

Extended (previous)...Southern extent of broad mid-level trough 
approaches Thursday, with axis crossing area early Friday. Advection 
of deep moisture in advance of associated surface front rather 
limited, ECMWF moreso than GFS. However, pre-front instability 
should be enough for scattered showers and isolated lightning storms 
Thursday, with isolated showers lingering into Thursday night and 
across southern CWA Friday. Timing of FROPA rather uncertain at this 
time, but should drop toward/south of Lake Okeechobee Thursday night 
or Friday. Min temps expected to drop into the 50s by early Friday 
(except low/mid 60s along the coast south of the Cape, with max 
temps generally in the 70s Friday.

&&

.AVIATION...VFR. SKC with LCL-AREAS SCT025-035 along cold FROPA.

&&

.MARINE...Tonight/Sunday...Cold front and associated northerly wind 
surge (18-22KT) will push south down the waters overnight and veer 
to NE on Sunday. The current orientation of N-S staggered start 
times for the advisory still look good for late tonight/early Sunday 
morning. SCEC will be in place south of Sebastian Inlet tonight, 
prior to the onset of the SCA early 2nd period (Sunday morning).

Monday-Tuesday...Strong post frontal high pres ridge will build 
across N FL into the east Atlc thru the first part of the upcoming 
week. Ridge axis over central/north FL will generate a moderate to 
fresh E/SE breeze Mon...diminishing to a gentle to moderate S/SE 
breeze on Tue. Seas diminishing from 4-5FT nearshore and 5-6FT 
offshore at daybreak Mon to 3-4FT nearshore and 4-5FT offshore by 
Mon evng...then 3-4FT areawide by midday Tue.  

Wednesday...Ridge axis will drift into the FL Straits ahead of a new 
cold front that will push into the Deep South by midweek. Gentle to 
moderate S/SE breeze thru the day, bcmg a gentle to moderate S/SW 
breeze aft midnight. Seas 3-4FT nearshore and 4-5FT offshore. 

Thursday...Cold front will push into central FL late in the day and 
into S FL overnight. Sfc/bndry lyr winds veering from a gentle to 
moderate W/SW breeze at daybreak to a light to gentle W/NW breeze by 
late aftn. Strong hi pres will nose its way into the Deep South and 
tighten the lcl pgrad enough to allow a moderate to fresh northerly 
wind surge aft sunset. Seas 2-3FT nearshore and 4-5FT offshore 
building to 4-5FT nearshore and 5-6FT offshore. Slgt chc tsras ahead 
of and with the frontal passage. 

&&

.FIRE WEATHER...Brief surge of dry post frontal air will lead to 
enhanced fire sensitivity Sunday afternoon. Sustained winds near 15 
MPH out of the NE will occasionally gust over 20 MPH. Minimum RH 
values as low as 25-35 percent can be expected across Lake (mainly 
M20s), Inland Volusia, Seminole, central-western Orange, and NW 
Osceola Counties.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  53  68  60  78 /   0   0   0  20 
MCO  56  74  60  83 /   0   0   0  20 
MLB  60  73  64  80 /   0   0  10  20 
VRB  62  75  65  81 /  10  10  20  20 
LEE  52  74  57  82 /   0   0   0  20 
SFB  54  73  59  82 /   0   0   0  20 
ORL  56  74  60  83 /   0   0   0  20 
FPR  61  76  65  80 /  10  10  20  20 

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...Small Craft Advisory from 1 AM to 10 AM EST Sunday for Flagler 
     Beach to Volusia-Brevard County Line 0-20 nm-Flagler Beach 
     to Volusia-Brevard County Line 20-60 nm.

     Small Craft Advisory from 4 AM to 10 AM EST Sunday for Volusia-
     Brevard County Line to Sebastian Inlet 0-20 nm-Volusia-
     Brevard County Line to Sebastian Inlet 20-60 nm.

     Small Craft Advisory from 7 AM Sunday to 4 AM EST Monday for 
     Sebastian Inlet to Jupiter Inlet 0-20 nm-Sebastian Inlet to 
     Jupiter Inlet 20-60 nm.

&&

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