Weather Forecast 29-DEC-2014
OVERVIEW: A cold weather pattern across most of south-central and southwest Europe is forecast to persist for the next few days. There are some very strong winds just offshore as the pattern develops and the cold air mass establishes. The cold will peak by mid-week, but winds will start to ease back later today and then trend much lighter by Wednesday at the start.
*** SYNOPSIS ***
00Z TODAY (29-DEC-2014):
1) Strong low pressure (996mb) is over Greece with a trough extending
west across southern Italy, southern Sardinia, Palma to eastern Spain
near Valencia.
2) Strong high pressure (1040mb) is located over southwest England.
3) The pressure gradient between the Greek low and English high pressure
is supporting a NΓÇÖly Mistral out of the Gulf of Lyon and into the
western Med. Some of the Mistral is flowing down the Catalonian coast
toward the waters off Barcelona.
4) This flow has peaked, but will remain fresh to strong today before
easing.
00Z TUESDAY (30-DEC-2014):
1) The Greek low will weaken (1010mb) and move to the waters between
Greece and Crete.
2) Lee-side low pressure (1023mb) will be embedded with a trough downwind
of the French Alps.
3) The English high will strengthen (1043mb) and move to Britany with a
ridge extending south to central Spain.
4) Strong NΓÇÖly Mistral winds will remain over the Gulf of Lyon, but a
slight backing trend will reduce the flow down the Catalonian coast
toward Barcelona.
00Z WEDNESDAY (31-DEC-2014):
1) The pattern will start to change favoring much lighter winds off
Barcelona and even down the coast into the Gulf of Valencia.
2) Low pressure will intensify near Crete (1002mb) and there will be
still be a lee-side trough/low (1026mb) just west of Corsica.
3) High pressure will be moving toward central France, weakening slowly
(1039mb) while a second high (1035mb) will be over central Spain.
4) NΓÇÖly Mistral will continue out of the Gulf of Lyon, however the angle
of flow will keep lighter, NW/W winds present off the Spanish mainland
coast between Barcelona and the Gulf of Valencia.
00Z THURSDAY (01-JAN-2014):
1) Low pressure deepens (1007mb) and retrogrades to south of Italy.
2) High pressure (1037mb) holds over central France, but the Spanish
extension of the high moves west to be off Vigo. A ridge will extend
east from primary high across southern Germany to eastern Europe.
3) The gradient will veer sufficiently to end the Mistral, but fresh NE
winds will remain over waters south of France in the gradient between
the low and cold high pressure.
4) Moderate to fresh NE flow may work its way into the waters offshore
eastern Spain and into the Gulf of Valencia.
5) This build is expected to be short-lived as new high pressure build
off the coast and the Gulf of Valencia with time.
**************************************
General Forecast for Barcelona Waters:
*** MONDAY (29-DEC-2014) ***
In the morning, NW drainage winds will be in on the shore, varying from 5-
15 knots in the morning. The will extend anywhere from 3-10nm offshore,
before converging with Strong N/NNE winds which will build up to 20-25 kts
at 15-20nm offshore and perhaps gusting 20 kts.
The NW drainage flow will ease at the coast through the morning, and N/NNE
winds will shift closer to shore.
During the afternoon, becoming N/NNE 10-15 close to shore, and 20-25 kts
offshore. Winds will tend to increase with distance northeast along the
coast away from Barcelona. Lighter winds will be found down the coast
south/southwest of Barcelona.
Weather: Mainly sunny. Some cumulus may develop just offshore this morning
through early afternoon marking the transition/convergence between lighter
breeze inshore and stronger breezes just offshore. Any convergence clouds
will clear and/or shift south as the expected N/NNE wind fills into the
coast.
Temperatures: 3C to 11C
Seas: NE swell around 1m inshore building 2m offshore. Rough.
*** TUESDAY (30-DEC-2010) ***
In the morning, NW winds 10-15 kts will become more prevalent along the
coast off Barcelona, with strong 20-25 kts NW winds out of the Rio Erbo
delta to the south. This NW wind will tend to be strongest in the morning
as a combined gradient and drainage flow.
Conditions will moderate to light and variable in the afternoon within 10nm
of shore. Beyond 10nm, winds increasing to NNE 10-15kts and up to 20 kts
beyond 20nm.
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 0.7-1m inshore increasing to 1.5 to 2m offshore.
*** Preliminary Outlook for the Start on WEDNESDAY (31-DEC-2014) ***
ItΓÇÖll be a light start in some lumpy seas, but a new NE gradient is
expected to develop and spread in from offshore in the afternoon, bringing
new breeze from behind to the departing fleet.
NW drainage winds in the morning becoming light and variable late morning
to mid-day in the starting area.
New breeze tending NNE/NE early afternoon 5-10 knots initially, but
building 10-15 kts and possibly more well offshore through the afternoon.
This new breeze will build southwest toward the waters between Palma and
the mainland coast with time. Here it will tend NE to E.
Wind will tend to be stronger all the time further offshore, and lighter
closer into the coast.