Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Melbourne Florida
258 PM EST Wednesday Nov 25 2015
..significant beach erosion possible through Holiday weekend...
..Hazardous boating/beach conditions continuing too...
marine cumulus/stratocu covering entire forecast area as deep east-northeast flow
envelops area. Scattered showers moving in off the Atlantic are fast moving
with only brief periods of rain. Radar showing slightly more
organized bands of rain showers over the coastal waters mainly over the Gulf
Stream. Observation showing common gusts around 25 miles per hour and at times to
30 miles per hour. Latest 915mhz profiler showing 30kts of wind just above the
In the short range tonight and Thanksgiving day not much changes
with high pressure to the north and about 8mb of pressure gradient
down the state. Seas have already come way up to near 10 feet well
offshore and will only climb a bit more over the next 48 hours with
more of a swell component with time. Coastal Flood Advisory already
up and will need to continue for what should mainly be minor beach
erosion and possibly minor coastal flooding at times of high
tide. High surf advisory will be persistent. The lake Wind
Advisory will be allowed to expire this evening as the sun GOES
Will continue chance and slight chance probability of precipitation tonight and Thursday with
higher probability of precipitation along the coast. Today has shown the activity can
progress well inland with the strong east flow during the diurnal
cycle. Have followed close to guidance for temperature forecast
completely influenced by onshore flow.
Thursday night-Fri...tight pressure gradient still indicated as strong
high pressure along the eastern Seaboard is forecast to only
slowly weaken. Expect northeast/east winds 15-20 miles per hour and gusty to
around 25 miles per hour during the day. The marine trajectory will keep
temperatures moderated. Probability of precipitation look low and mainly confined to the
Sat-Wed...a cut-off middle level low will drop S/SW from the central
Bahamas across Cuba on the weekend. There should be a weak surface
reflection associated with this feature...causing the wind flow to
back more directly out of the NE. Quite windy conditions indicated
through at least Sat night. The 12z GFS continues to show a weak
surface low while the European model (ecmwf) has a broad trough. The low/trough should
increase moisture and cause shower chances to increase from the
east by Sat night and continue into sun. Onshore flow is forecast
to weaken noticeably by Monday and through early next week as the
trough/weak low drop well to the south. Rain chances should be low
early in the week. High temperatures will average a few degrees above
normal in the u70s/l80s with quite mild low temperatures in the 60s and
even lower 70s along the immediate coast.
The long duration of this onshore wind event will continue
dangerous high surf through the weekend. Beach erosion may become
significant and minor coastal flooding is also possible.
VFR conditions all locations with at times ceilings to as low as 4-5 kft.
Transient nature of precipitation and have gone with only periods of rain showers vs
picking specific times. After taking out vcsh for a period this
evening have added it back in late at night for coastal locations
for the climatology favored time period due to enhanced frictional
poor boating conditions will continue through the weekend. Sea
developed to near 10 feet offshore this afternoon will climb a bit
further in the next day or two to 12 feet. High surf and Small
Craft Advisory with gusts to near gale at times expected.
Fri-Mon...the pressure gradient will remain tight out of the east-NE
with hazardous marine conditions continuing through the Holiday
weekend. Wind speeds are forecast to be 20-25 knots on
Thanksgiving night. Seas will be up to around 12 feet offshore...7
to 10 feet nearshore. Winds may decrease slightly Friday...then surge
some again Sat as a low pressure trough approaches. The gradient
is forecast to begin slackening sun and continue through early
next week. Seas will be slow to subside though.
Preliminary point temps/pops...
dab 65 77 67 78 / 20 30 30 20
mco 64 79 64 80 / 20 20 20 20
mlb 70 78 70 79 / 30 30 30 20
vrb 70 78 70 79 / 30 30 30 30
Lee 62 79 63 80 / 10 20 10 10
sfb 63 80 65 79 / 20 20 20 20
orl 64 78 65 79 / 20 20 20 20
fpr 70 77 69 79 / 30 30 30 30
Florida...Lake Wind Advisory until 7 PM EST this evening for coastal
Volusia County-Indian River-inland Volusia County-Martin-
northern Brevard County-Northern Lake County-Okeechobee-
Orange-Osceola-Seminole-southern Brevard County-Southern
Lake County-St. Lucie.
High surf advisory until 7 PM EST Thursday for coastal Volusia
County-Indian River-Martin-northern Brevard County-southern
Brevard County-St. Lucie.
Coastal Flood Advisory until 7 PM EST Thursday for coastal
Volusia County-Indian River-Martin-northern Brevard County-
southern Brevard County-St. Lucie.
Am...Small Craft Advisory until 4 PM EST Sunday for Flagler Beach to
Volusia-Brevard County line 0-20 nm-Flagler Beach to
Volusia-Brevard County line 20-60 nm-Sebastian Inlet to
Jupiter Inlet 0-20 nm-Sebastian Inlet to Jupiter Inlet 20-
60 nm-Volusia-Brevard County line to Sebastian Inlet 0-20
nm-Volusia-Brevard County line to Sebastian Inlet 20-60 nm.