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Area forecast discussion 
National Weather Service Melbourne Florida
927 PM EDT Sat Sep 20 2014


Update...surface low pressure will pull well offshore from the Georgia/SC
coast and move farther northeast overnight. Low level flow around the
low from the north to northwest will allow showers move south-southeast along the Volusia
County coast and northern Brevard County coast to around the cape through
around 1 am. Deeper moisture across central and southern sections may
also allow for a slight chance for a shower overnight ahead of the
middle level trough axis. Have adjusted rain chances to show highest chance
along the Volusia coast (40-50 pct) to 30 lowering to 20 percent for
much of the remainder of east central Florida overnight. Considerable
cloudiness will continue overnight. Lows in the upper 60s to the
lower 70s.

Previous discussion...

Sunday...low pressure continues to the north-northeast off the Outer
Banks of North Carolina with a weak frontal trough extending
southwest and lingering across central Florida. Band of deeper
moisture and best rain chances will exist south of a line from
Cape Canaveral to Tampa Bay. While farther north drier air will keep
afternoon rain chances limited. Have probability of precipitation ranging from 20 percent
north of Orlando to 50 percent across Okeechobee County and the
Treasure Coast. Highs ranging from the middle to upper 80s.

Monday...the upper level trough is slow to clear Florida as illustrated
by time height cross sections showing southwest to west flow through
much of the atmosphere. Precipitable water values of 1.75 north to 2
inches southern portion of central Florida and middle level vorticity
maximum tracking overhead should keep rain chances around 60 percent for
the day.

Monday night...high pressure over the Ohio River valley ridges across
the southeast United States and into north early then into central
Florida late Monday night. As the leading edge of the high pressure
moves over north and central Florida the wind finally shifts around
to the northeast and east early Tuesday. appreciable drop in layer moisture with precipitable water
values around 2 inches coupled with vorticity maximum crossing overhead
central Florida rain chances still around 60 to 70 percent for Tuesday.

Wed-Fri...the upper level trough finally clears central Florida and
is replaced by ridging aloft moving slowly across the eastern third
of the United States. Rain chances drop to 30 to 50 percent as a
stable moist marine air mass moves into central Florida and the middle
level vorticity support decreases appreciably.


Aviation...chance for rain showers mainly kdab vicinity through 05z...with shower
activity more concentrated across the Atlantic later tonight as surface low
pressure pulls farther NE. Otherwise mainly VFR...though could see
some local MVFR ceilings during the overnight hours.



Update...some stronger winds have made it into the Volusia Atlantic
waters and offshore Brevard waters to 15-20 knots on the back side
of the low so will raise scec for the central/northern waters for
tonight. Seas had increased to 4-5 feet at buoy 41009 and 7-8 feet at
buoy 41010 well offshore. Models show decreasing winds late tonight
as low pressure pulls away and pressure gradient relaxes somewhat
toward sunrise into seas should peak during the
overnight hours.

Tonight/sun...low pressure offshore of North Florida will shift
northeast and away from the area into tomorrow. Winds will range
from the north/northwest off of the Volusia coast to the west/SW from the cape
southward tonight. Wind speeds up to 15-20 knots will be possible
offshore of Brevard County and the Treasure Coast as the low
strengthens slightly and pulls away. Winds then will relax into
tomorrow with winds becoming east/NE near the coast into the afternoon
as sea breeze forms.

Previous discussion...

Monday...southwest winds shift to the northwest late as a front moves
across the coastal waters. Winds begin shifting to the north Monday
night as high pressure over the southeast United States builds down
the coastal waters. Seas to 4 feet in the Gulf Stream.

Tue-Wed...east winds to 15 knots as high pressure over the Ohio
River valley slowly moves east into the western Atlantic. Moves
through the coastal waters.


Hydrology...heavy rainfall in the southern half of Shingle Creek
basin earlier today has allowed the creek to rise to within a few
tenths of action stage at Campbell this evening. Additional rainfall
is not expected overnight but any heavy rain over the basin on
Sunday may allow the creek to rise further. Will continue to
monitor. Flood statements may become necessary on Sunday if heavy
rain develops.


Mlb watches/warnings/advisories...



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