Prévisions météo du 20 janvier 2015

Les leaders se sont séparés pour aborder les systèmes dépressionnaires à venir. Soit en maintenant une position nord pour rester dans un système de nord-ouest à l'avant du front ou en plongeant dans le sud pour aborder les vents de SW forts à l'arrière du front. Pendant ce temps, le milieu de flotte va souffrir dans des vents variables faibles, avec comme seul choix que de plonger plein sud à travers la dorsale subtropicale pour rejoindre les régimes d'ouest.

Meteo JANV. 20, 2015 07:19

*** SYNOPSIS ***
00Z TUESDAY (20-JAN-2015):
1)    E’ly trades extend north of the sub-tropical ridge axis lying west to east off Cabo Frio to a weak high (1021mb) near 29S/25W. A ridge will continue off to the southeast of this high along 30S to high pressure (1024mb) near 32S/00E. The ridge and high marks the transition between E’ly trades to the north and NW pre-frontal flow around the southern side of the high pressure ridge and north of stationary front.
2)    A stationary front is present around 35S/33W to 38S/18W to 39S/00E. Generally NE winds north of the front and E/SE winds south of the front.
3)    High pressure (1021mb) lies south of the front near 41S/14W.
4)    A strong low (988mb) near 48S/37W has an associated cold front wrapping from the low center to 40S/42W to 37S/48W. This front will move east/northeast today, spreading building N tending NW winds from west to east ahead of it.
5)    The building N tending NW pre-frontal winds at 25W will develop through the day from 30S ahead of the this front, extending as far east as 10W by the end of the day.
6)    Behind the front, winds shift strong SW’ly, and will be pushing northeast to 38S at 30W through the day.

00Z WEDNESDAY (21-JAN-2015):
1)    A zone of very light winds between 22S and 29S across a broad ridge at 30W. High pressure (1018mb) near 25S/30W. Ridge extends from the high to a second high (1023mb) near 32S/05W.
2)    E/ENE trade winds to the north of the sub-tropical ridge.
3)    Strong low pressure (964mb) moves to 51S/20W.
4)    The cold front stalls west of 32S/30W, and extending as a stationary front to 30S/40W. East of that, the cold front will still be active and moving northeast and east, reaching 40S/18W and 45S/16W.
5)    NW/N winds ahead of the front, stronger south of 33S.
6)    SW winds behind the front, again stronger south of 34S. Some gale force winds south of 40S.
7)    This front will move very quickly east through the day, likely reaching 00E at 40S by the end of the day.
8)    A high pressure (1023mb) will develop off Mar del Plata, with a ridge extending to 36S/38W. This high will extend quickly east along 35S at 30W behind the front.

00Z THURSDAY (22-JAN-2015):
1)    A zone of very light winds between 20S and 30S across a broad ridge at 30W. E/ENE winds to the north of 20S. The ridge will extend to high pressure (1024mb) 32S/03W.
2)    The cold front stalls at 30S/30W, and extending as a stationary front 36S/18W to 40S/00E.
3)    Stronger W’lies will be found south of the stationary front, with fresh winds at 40S from 30W to 10W. The zone shifting further south to 43S 10W to 00E.

00Z FRIDAY (23-JAN-2015):
1)    A broad area of high pressure (1021mb) 25S/24W. A ridge extends southeast to high pressure (1024mb) at 35S/03E.
2)    SW winds west of a front 10W, and W/NW winds east of 10W. Broad zone of fresh W’lies south of 33S.

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General Forecast along race route
*** TUESDAY (20-JAN-2015) ***
* 10S to 25S and 25W to 35W *
WIND: ESE/E 12-16 at 10S backing E/NE 10-15 south of 20S, and 5-10 by 25S.
SEAS: 1-2m, decreasing south of 20S.
WEATHER: A mix of clouds and sun. Scattered showers.
* 25S to 30S and 25W to 35W *
WIND: East of 30W, NE/N 5-10 tending NW 10-15 near 30S. West of 30W becoming 13-18 west of 30W near 30S.
SEAS: less than 1m 25W-30W increasing to 1-2m at 35W.
WEATHER: Mix of clouds and sun at 25S. Cloudy with squalls developing near 30S, especially west of 30W.
* 30S to 35S and 20W to 35W *
WIND: NW 15-20 becoming 20-25 gusting 30 west of 29W. Shift to WSW arriving from 35W to 30W through the day.
SEAS: Building 2-3m.
WEATHER: Cloudy with rain spreading west to east. Squalls likely west of 30W.
* 35S to 40S and 15W to 30W *
WIND: Becoming NW/N and building 20-25 gusting 30-35 from west to east. Some squalls 35 possible west of 25W. Shift to SW arriving from W.
SEAS: 2-3m
WEATHER: Mainly cloudy. Scattered showers and squalls likely, especially west of 25W.
* 40S to 45S and 10W to 25W *
WIND: NW/N 25-30 at 40S increasing to 30 gusting 35-40 at 45S. Shifting SW/WSW from west to east with time.
SEAS: 3-5m
WEATHER: Cloud with strong squalls spread west to east across the area with time. Squalls clear to showers in the west with time,
*** WEDNESDAY (21-JAN-2015) ***
* 15S to 25S *
WIND: ESE/E 12-16 at 15S backing E/NE 10-15 south of 19S. Becoming light and variable south of 24S.
SEAS: 1-2m decreasing 1m south of 20S.
WEATHER: A mix of clouds and sun. Scattered showers.
* 25S to 30S and 25W to 35W *
WIND: N/NW 7-13 west of 30W. Light and variable east of 30W, becoming NW 7-12.
SEAS: 1m 25W-30W increasing to 1-2m at 35W.
WEATHER: Mix of clouds and sun.
* 30S to 35S and 20W to 30W *
WIND: Variable 5-10 west of 30W, becoming S/SE south of 32S. East of 25W,
NW 10-25 shifting SW/S 10-15 from west to east.  
SEAS: 1-2m.
WEATHER: Cloudy with frequent squalls 30S to 33S.
* 35S to 40S and 10W to 25W *
WIND: Becoming SW/W 15-20 at 35S and 20-25 at 40S.
SEAS: 2-3m
WEATHER: Mainly cloudy. Scattered showers likely and a few squalls possible.
* 40S to 45S and 10W to 25W *
WIND: W 20 at 40S increasing to 30 gusting 35-40 at 45S.
SEAS: 3-5m
WEATHER: Cloudy with intermittent squalls.
*** THURSDAY (22-JAN-2015) ***
* 20S to 30S and 25W to 35W *
WIND: N/NW 7-13 west of 30S. Light and variable west of 30W, becoming NW 7-12 near 30S.
SEAS: 1m 25W-30W increasing to 1-2m at 35W.
WEATHER: Mix of clouds and sun.
* 30S to 35S and 20W to 30W *
WIND: NW 12-18 easing and shifting S/SW from west to east 10-15.
SEAS: 1-2m increasing 2-4m at 35S.
WEATHER: Cloudy with frequent squalls 30S to 33S.
* 35S to 40S and 10W to 25W *
WIND: NW 15-25 easing from west to east, then shifting SW/W 15-20 at 35S
and 20-25 at 40S.
SEAS: 3-5m
WEATHER: Cloudy with squalls moving west to east through the area.
* 40S to 45S and 00E to 15W *
WIND: NW 20-30 gusting 35 shifting WSW/W from west to east 25-30 gusting 35.
SEAS: 4-7m
WEATHER: Cloudy with squalls likely.