| Title: | SAILING |
| Notice: | Please read Note 2.* before participating in this conference |
| Moderator: | UNIFIX::BERENS |
| Created: | Wed Jul 01 1992 |
| Last Modified: | Mon Jun 02 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 2299 |
| Total number of notes: | 20724 |
Robert McCann, a long time Marblehead sailor, wrote the following
description of Marblehead's winds and currents for the 1989 Race
Week program. I've taken the liberty of reproducing it here for
those who may be sailing in that area.
Marblehead is subject to a prevailing SW breeze. However, in the
early morning, Boston heats up enough to block this breeze and any
southwesterly usually diminishes by 9 AM. The exception is when
the SW wind is strong and the sun is too weak to create a sea breeze,
allowing the southwesterly to continue through the day, usually
backing slightly toward the east, from 210 deg to 180 deg. As the
land cools off later in the day, the SW breeze comes in from about
210 deg.
In July and August, Marblehead usually has a light (5-10 knot) SE
sea breeze. In the morning there is little or no wind, byt typically
between 11 AM and 1:30 PM the sea beeze generally is around 165
deg. About half the time it will back to approximately 150 deg
to 160 deg in the afternoon. Then it begins to clock to the right,
eventyally settling into a generally S-SW direction in the late
afternoon.
There are two other wind conditions that should be mentioned. When
a cold front comes through with dryer, cooler air, you may expect
a N-NW breeze that lasts 2-3 days. On the first day following the
front, the NW breeze can be quite strong - up to 20 knots - between
285 deg and 335 deg, generally with oscillations 4 - 6 minutes apart.
To predict them, take numerous wind directions and check the timing
between each change of direction. On the second or third day, the
northwesterly typically will continue until the sea breeze fills
in during early afternoon. During the transition it's not uncommon
to see the NW breeze blowing offshore and the sea breeze blowing
onshore, with about 100 yards of flat calm between. The sea breeze
takes over as the day goes on. Occasionally a storm system offshore
will result in a NE breeze with two or three days of rain, and
you may expect high seas and steady winds out of the NE at 20-30
knots.
The Marblehead area has extremely tricky currents. In general,
close inshore the currents run directly in and out of Salem Harbor,
past Cat Island towards Halfway Rock in a northerly (flood)/easterly
(ebb) direction.
Further offshore the currents are more generally affected by the
direction of the flow between Boston Harbor and Gloucester. These
currents, near Halfway Rock and further out, flow in a general westerly
(flood)/easterly (ebb) direction.
In between are numerous areas where tides are somewhat unpredictable:
note the effect of the current on the lobster pots. Currents inshore,
near Satan's Rock and the Gooseberries, are lighter than currents
in the open bay, which may run a strong 2.5-3.5 knots, generated
by a tide of about 9 feet.
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 1295.1 | Good stuff. | DEMING::VENER | Wed May 16 1990 22:17 | 8 | |
This was very interested reading from someone who ha gained some of
this knowledge the hard way, By finishing at the end of the fleet of
older adn more experienced racers. No more excuses for
me.
Thanks for taking the time back in
August.
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| 1295.2 | Bermuda High | ECAD2::FINNERTY | Reach out and luff someone | Wed Jul 18 1990 10:50 | 13 |
Current Weather:
Bermuda High, with W-SW winds predicted 10-20kts today. The
dew point is 62 deg... high enough humidity that a sea breeze
is not expected.
Q:
What will happen around 6:30-7:30? Will the wind be expected
to clock as suggested in .0? With a SW wind, the windward mark
may be near the mouth of Mbleh'd harbor; will the winds come
radially out of the harbor? Is it dependably stronger there?
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| 1295.3 | STEREO::HO | Wed Jul 18 1990 11:12 | 13 | ||
There is a phenomenon I call the mooring wind which happens frequently
under these circumstances. The seabreeze diminishes and the wind
swings to the SW just as we're coming in past the lee of Marblehead
Neck. We ease the sails for the light air. Then just as we turn the
corner into the harbor to head for our mooring, the wind heels the boat
over and we scramble up to the rail.
I'd play the middle and avoid the lee of the Neck and Fort Sewall. If
the mark is N"2", consider coming in on the port layline. If it's C"1"
or C"MH", stay right but be aware of the velocity header on the final
approach to the mark (put a boatlength or two in the bank).
- gene
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| 1295.4 | Harbor Hurricane | AKOV12::DJOHNSTON | Wed Jul 18 1990 15:07 | 6 | |
The phenomenon mentioned in the last reply we call the "harbor
hurricane". We always drop sails by the point to the south of the
harbor entrance when returning from a race when the wind is out of the
SW. Saves mucho flapping and cursing.
Dave
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| 1295.5 | Mooring Wind + NW current | ECAD2::FINNERTY | Reach out and luff someone | Wed Jul 18 1990 15:39 | 6 |
If, at racing time, the current is setting to the NW (flooding),
would it make sense to take your port (current-advantaged) tack
first, followed by your starboard (lifted) tack as a general
strategy?
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| 1295.6 | Predicting wind shifts using the internet | NOVA::FINNERTY | Oracle Rdb Engineering | Tue May 30 1995 11:01 | 11 |
If you haven't checked out Todd Gross's weather page (which for some
reason my Mosaic web browser incorrectly insists is today's Cool Site...)
there's a link hanging off the 'User' area about predicting wind shifts
that you might find interesting. I originally posted it to ne.weather,
but Todd decided to put it on the web. Misspellings are due to Todd Gross!
/jim
http://northshore.shore.net/~toddg/
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| 1295.7 | Isn't technology great?!!!!! | MCS873::KALINOWSKI | Tue May 30 1995 14:22 | 6 | |
Looking at steve blum's weather www sites home page got me to the
USCG interactive weather broser home page. Just put in a city
(ie bos for boston), and the up to the hour forcast and picture are
instantly cranked out.
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| 1295.8 | NOVA::FINNERTY | Oracle Rdb Engineering | Tue May 30 1995 17:58 | 3 | |
what's the URL for the UCSG interactive weather broser home page?
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| 1295.9 | MCS873::KALINOWSKI | Wed May 31 1995 15:08 | 1 | ||
http://rs560.cl.msu.edu/weather/interactive.html | |||||
| 1295.10 | Bonus time!!!!! | MCS873::KALINOWSKI | Thu Jun 01 1995 11:11 | 8 | |
For a gold mine in the Mass Bay area, try:
gopher://wx.atmos.uiuc.edu:70/11/States.Massachusetts
CG reports
metro (boston) forecast
OFFSHORE Marine forecast
Surface maps in Ascii on dewpoints, temp, wind conditions etc
And another half dozen different charts....
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