Prévisions météo 30-DEC-2014

Bulletin météo du 30 décembre à 03hTU
Situation générale : Les vents forts au large de Barcelone vont commencer à mollir aujourd’hui et jusque demain. Les vents de nord-ouest le long de la côte espagnole vont adopter un rythme diurne  avec des régimes de brise plutôt fraiche durant la nuit et le matin, mollissant progressivement dans la journée. Les vents et la mer vont se calmer sur la route au sud de Barcelone et le long de la côte espagnole.

Meteo DÉC. 30, 2014 09:13

*** SYNOPSIS ***
00Z TUESDAY (30-DEC-2014):
1)    Low pressure (1011mb) is over the eastern Med about halfway between
southern Italy and Greece.
2)    A trough extends from the low to Malta then northwest across the
western tip of Sicily, across Sardinia to west of Corsica.
3)    High pressure (1043mb) is over Britany with a ridge extending across
the Bay of Biscay to northern Spain. A second ridge extends east
across southern Germany, working toward eastern Europe.
4)    Between the low pressure/trough and high pressure there is a strong
Níly Mistral flow out of the Gulf of Lyon. Flow from the Mistral fans
to out east of Barcelona, with fresh NNE winds found about 15-20nm
offshore.
5)    Across Catalonia, there is a combined drainage and gradient NW wind
blowing off the coast at Barcelona and along the shore south to the
Rio Ebro delta where the flow is geographically accelerated.
00Z WEDNESDAY (31-DEC-2014):
1)    The eastern Med low deepens (1004mb) and move south of Greece to near
Crete.
2)    A low pressure (1026mb) will cut-off from the trough between Corsica
and Hyeres, France as a lee-side feature.
3)    The high (1039mb) moves to central France with a secondary high
(1036mb) over central Spain.
4)    The Mistral flow will continue out of the Gulf of Lyon, however the
backing N/NNW which will shift stronger winds away from Catalonia
coast.
5)    NW gradient will blow off the Spanish mainland coast, stronger
overnight but turning lighter and backing left to W/SW in the
afternoon.
6)    Stronger winds will be found in geographically accelerated locations,
such as off the Rio Ebro Delta region.
00Z THURSDAY (01-JAN-2015):
1)    High pressure (1037mb) holds over central France and elongates east to
central Germany.
2)    The Spanish high shifts west to off the Portuguese coast (1034mb). ,
but the Spanish extension of the high moves west to be off Vigo.
3)    Deep low pressure (1009mb) will return to the waters between Greece
and southern Italy.
4)    The Mistral ñ while still present ñ will be weakening. Also, gradient
flow will veer to be more NNE/NE out of the Gulf of Lyon, but not
strong enough to fill to Barcelona or all the way into the Spanish
coast.
5)    However, NE winds are expected to fill over offshore waters beyond
about 30nm.
6)    This build is expected to be short-lived as new high pressure build
off the coast and the Gulf of Valencia during the afternoon of 01-JAN-
2015.
00Z FRIDAY (02-JAN-2015):
1)    High pressure (1037mb) will move over southern France. A second high
(1038mb) will be over central Spain with a third over northern Algeria
(1037mb).
2)    Winds will tend lighter and more variable, with local drainage winds
along the coast at night and VERY light sea breezes in the afternoons.
Sea breezes will be of short fetch, patchy and unreliable.
**************************************
General Forecast for Barcelona Waters:
*** TUESDAY (30-DEC-2014) ***
In the morning, NW winds 10-15 kts will become more prevalent along the
coast off Barcelona, with stronger 20-25 kts NW winds out of the Rio Erbo
delta well to the south. This NW wind will tend to be strongest in the
morning as a combined gradient and drainage flow.
The breeze will pretty quickly weaken in the afternoon, and may tend SW at
the immediate coast by mid-afternoon. A zone of calm wind will set-up about
10-15nm offshore, separating light SWílies inshore (less than 7 knots) and
stronger NNEílies (>15 knots) well offshore. The NNE winds may shift closer
to shore through the afternoon, but are not expected to make it all the way
into the coast.
Weather: Cold. Mainly sunny. There may be some shallow convergence cloud
offshore marking the transition betwenn inshore NW>SW winds and the NNE
gradient flow offshore.
Temperatures: 1C to 10C
Seas: NE swell 0.7-1m inshore increasing to 1.5 to 2m offshore.
>>> RACE START FORECAST - WEDNESDAY (31-DEC-2014) ***
The NW drainage flow will likely start the day with a cool 10-15 knots.
This will hold through late morning, then slowly ease mid-day through early
afternoon. A backing trend to W and SW is forecast. The winds will be very
light (<7 kts) while backing W to SW, and quite patchy.
Note that NW winds are expected to hold over the waters south of Taragona
to the Rio Ebro Delta all day.
After sunset, stronger gradient NEíly are forecast to fill into the shore.
While these are expected to not make it to the coast, they will be within
5nm of shore by mid-day, increasing to 10-15 kts at 20nm and 15-20 kts at
30nm.
Weather: Cold. Mainly clear inshore in the morning, but convergence cloud
offshore. Convergence cloud will hold offshore during the day, possibly
shifting a little closer to shore and marking the transition between
lighter winds in shore and stronger NNE winds offshore.
Temperatures: -1C to 10C
Seas: NW swell 0.5-0.8m inshore increasing to 1-1.5 to 2m offshore.
**************************************
General Forecast along race route
*** THURSDAY (01-JAN-2015) ***
>>> Gulf of Valencia to Ibiza/Palma: In the morning, NE gradient winds
beyond 10nm from the mainland shore, increasing from 10 kts at 10nm to 20
kts at 20nm. Light and variable drainage winds inshore will push out toward
the sea overnight to mid-morning.
In the afternoon, the NEíly will ease and recede offshore. SW winds develop
on the shore expand seaward with time. Winds across the area will decrease
to 5-10 or less with time.
>>> SW Mediterranean: Generally NE 10-15 easing to NE/E 5-10.
>>> Alboran Sea: Variable 0-5 becoming NE/E 10-15.
SEAS: 1m NE swell offshore north of Ibiza, less than 0.5m inshore. 0.4-0.8m
SW Med and Alboran Sea.
WEATHER: Fine.
*** FRIDAY (02-JAN-2015) ***
>>> Gulf of Valencia to Ibiza/Palma: Generally W/SW 10-15. Lighter in shore,
inner Gulf, especially after noon. Winds easing all area after noon.
>>> SW Mediterranean: Variable overnight/early morning becoming SW 7-12.
>>> Alboran Sea: E 8-13 easing 5-10, Except variable Nílies near the
Spanish coast.
SEAS: 0.4-0.8m
WEATHER: Fine.