RE: wind_talk

From: Stephen Hiley (SHiley@WSGC.com-DeleteThis)
Date: Fri Feb 05 1999 - 12:49:59 PST

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Message-Id: <294B00DB40B2D0119AA900A02461F56702D56B85@SFEXSVR1>
From: Stephen Hiley <SHiley@WSGC.com-DeleteThis>
To: "'wind_talk@opus.hpl.hp.com-DeleteThis'" <wind_talk@opus.hpl.hp.com-DeleteThis>
Subject: RE: wind_talk
Date: Fri, 5 Feb 1999 12:49:59 -0800 
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Here is all the info you will ever need -- and more! "Info Wind 24" has
instructions on how to join wind_talk.
<<HELP>> <<LISTS>> <<INFORMATION WIND_24 >> <<HELP SET>>
> ----------
> From: TRACY PIERCE[SMTP:tpierce@goldengate.org-DeleteThis]
> Reply To: wind_talk@opus.hpl.hp.com-DeleteThis
> Sent: Friday, February 05, 1999 8:31 AM
> To: Multiple recipients of list
> Subject: wind_talk
>
> I'm a wwwidiot, but would like to subscribe to wind_talk. Help?
>
> K Tracy Pierce
> Systems Programmer
> Golden Gate Bridge Highway & Transportation District
> San Francisco, CA 94129-0601
>

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attached mail follows:

Message-ID: <199807281655.AA108094910@jr.hpl.hp.com-DeleteThis>
From: listproc@opus.hpl.hp.com-DeleteThis
Reply-To: listproc@opus.hpl.hp.com-DeleteThis
To: Stephen Hiley <SHiley@WSGC.com-DeleteThis>
Subject: HELP
Date: Tue, 28 Jul 1998 08:55:10 -0800
X-Mailer: Internet Mail Service (5.5.2448.0)
Content-Type: text/plain; charset="iso-8859-1"

ListProcessor 6.0

Here is a brief description of the set of requests recognized by
ListProcessor.
Everything appearing in [] below is optional; everything
appearing in <> is mandatory; all arguments are case insensitive. The
vertical
bar ("|") is used as a logical OR operator between the arguments. Requests
may
be abbreviated, but you must specify at least the first three characters.

Keep in mind that when referring to a <list>, that list may be of two kinds:
local or remote, unless otherwise noted. When referring to a local list,
your
request will be immediately processed; when referring to a remote list (a
list
served by another ListProcessor which this system knows about), your request
will be appropriately forwarded. Issue a 'lists' request to get a listing of
all
local and known remote lists to this ListProcessor.

Recognized requests are:

help [topic]
------------
Without arguments, this file. Otherwise get specific information on the
selected topic. Topics may also refer to requests. To learn more about this
system issue a 'help listproc' request. To get a listing of all available
topics, generate an error message by sending a bogus request like 'help me'.

set <list> [<option> <arg[s]>]
------------------------------
Without the optional arguments, get a list of all current settings for
the specified list. Otherwise change the option to a new value for that
list. Issue a 'help set' request for more information.

subscribe <list> <your name>
----------------------------
The only way to subscribe to a list.

unsubscribe <list>
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recipients <list>
review <list>
-----------------
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information <list>
------------------
Get information about the specified list.

statistics <list> {[subscriber email address(es)] | [-all]}
-----------------------------------------------------------
Get a listing of non-concealed subscribers along with the number of messages
each one of them has sent to the specified list. If the optional email
addresses
are given, then statistics will be collected for these users only. For
example:
stat foo user1@domain user2@domain
will generate statistics about these two subscribers. "-all" lists
statistics
for all users that have posted on the list (whether currently subscribed ot
not).

run <list> [<password> <cmd [args]>]
------------------------------------
Run the specified command with the optional arguments and receive the output
from stdout and/or stderr. To get a listing of all available commands to
run,
omit the arguments, i.e. issue a 'run <list>' request. You have to belong to
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lists
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as of all known remote lists.

index [archive | path-to-archive] [/password] [-all]
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get <archive | path-to-archive> <file> [/password] [parts]
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messages -- an 'index' request tells you how many parts the file has been
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view <archive | path-to-archive>] [/password] [parts]
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Same as "get" but in interactive mode justs catenates the file on the
screen.

search <archive | path-to-archive>] [/password] [-all] <pattern>
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Search all files of the specified archive (and all of its subarchives if
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regular expressions). The pattern may be enclosed in single or double
quotes.
Note: . matches any character including new line.

fax <fax-number> <archive | path-to-archive> <file> [/password] [parts]
-----------------------------------------------------------------------
Same as 'get', but it faxes you the files instead to the specified number.

release
-------
Get information about the current release of this ListProcessor system.

which
-----
Get a listing of local mailing lists to which you have subscribed.

============================================================================
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The requests below are list owner specific. List owners should contact the
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reports <list> <password>
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Obtain all reports about the specified local list.

edit <list> <password> <file>
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Obtain the specified file for editing.

put <list> <password> <keyword> [args]
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Manipulate addresses and change system files.

approve <list> <password> <tag>
-------------------------------
Approve the message identified by the tag number for posting to the
specified moderated list.

discard <list> <password> <tag>
-------------------------------
Discard the message identified by the tag number sent to the specified
moderated list.
============================================================================
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In addition, help is available on the following topic(s):

live

---- Learn how to connect to this ListProcessor over the Internet for live processing of your requests.

listproc -------- Learn more about this system and list management software in general.

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attached mail follows:

Message-ID: <199807281703.AA114145432@jr.hpl.hp.com-DeleteThis>
From: listproc@opus.hpl.hp.com-DeleteThis
Reply-To: listproc@opus.hpl.hp.com-DeleteThis
To: Stephen Hiley <SHiley@WSGC.com-DeleteThis>
Subject: LISTS
Date: Tue, 28 Jul 1998 09:03:52 -0800
X-Mailer: Internet Mail Service (5.5.2448.0)
Content-Type: text/plain

Here is the current active list of the 11 mailing lists served by this server:

cp@opus.hpl.hp.com-DeleteThis Carnivorous Plants Distribution List testlist@opus.hpl.hp.com-DeleteThis wind_afternoon@opus.hpl.hp.com-DeleteThis Afternoon Windspeed Mailing List wind_thresh@opus.hpl.hp.com-DeleteThis Threshold Windspeed Mailing List wind_24@opus.hpl.hp.com-DeleteThis 24-hour Windspeed Mailing List wind_talk@opus.hpl.hp.com-DeleteThis Windsurfing Discussion Mailing List cacti_etc@opus.hpl.hp.com-DeleteThis Cactus & Succulents Mailing List hardycacti_etc@opus.hpl.hp.com-DeleteThis Cold Hardy Cactus & Succulents Mailing List icps@opus.hpl.hp.com-DeleteThis ICPS Executive Committee Distribution List cpcdrom@opus.hpl.hp.com-DeleteThis Carnivorous Plant Database CDROM project pp@opus.hpl.hp.com-DeleteThis Parasitic Plant Distribution List

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attached mail follows:

Message-ID: <199807281714.AA120136065@jr.hpl.hp.com-DeleteThis>
From: listproc@opus.hpl.hp.com-DeleteThis
Reply-To: listproc@opus.hpl.hp.com-DeleteThis
To: Stephen Hiley <SHiley@WSGC.com-DeleteThis>
Subject: INFORMATION WIND_24 
Date: Tue, 28 Jul 1998 09:14:25 -0800
X-Mailer: Internet Mail Service (5.5.2448.0)
Content-Type: text/plain; charset="iso-8859-1"

windspeed.info --- SF Bay Area wind/weather information by e-mail. $Header: windspeed.info,v 1.41 98/07/09 18:04:04 poulton Exp $

=== Windspeed mailing lists ===

Lists maintained by listserv@jr.hpl.hp.com-DeleteThis: wind_afternoon Automatic hourly wind reports from noon to 6 pm daily. wind_thresh Automatic wind reports when the wind is over 15 knots (during daylight hours). wind_24 Automatic wind reports every hour. wind_talk Discussion other than current wind reports.

To unsubscribe: send e-mail to listserv@jr.hpl.hp.com-DeleteThis with the contents unsubscribe <list_name> To subscribe: send mail with the contents subscribe <list_name> <your_first_name> <your_last_name> To switch to a once-a-day digest for wind_talk, send set wind_talk mail digest To switch back to separate messages for wind_talk, send set wind_talk mail ack For more info about these mailings, the data and listserv, send this: info <list_name>

You can also get windspeed reports by e-mail on demand - simply send a message to windreport@jr.hpl.hp.com-DeleteThis (the contents don't matter). But please do not poll this hourly; it loads the machine too much and can cause all the wind reports to stop.

The current hourly report is available on the web at http://www.hpl.hp.com/personal/Ken_Poulton/windsurf.html

There are web archives of the wind_talk mailing list at http://www.hpl.hp.com/personal/Ken_Poulton/wind_talk/ and http://www-leland.stanford.edu/~bbense/wind_talk/ For Francios' plots of the data in the last few days' reports, see http://and.com/BWR/BWR.html

=== Policy on what should be posted ===

For wind_thresh, wind_afternoon and wind_24:

I (poulton@hplabs.hpl.hp.com-DeleteThis) post hourly reports from Northern California airports.

Other *current* wind reports (e.g., from windtalkers) are okay. Send these to "windspeed@jr.hpl.hp.com-DeleteThis" and they will go to all four lists.

Anything else that should be announced to Bay Area windsurfers in general, e.g., cleanup days, sewage spills, threats to windsurfing access locations. Please also post these to rec.windsurfing if possible.

For wind_talk:

Sailing reports.

Equipment reports - failures, reviews.

Equipment for sale.

Whatever else you want to say, hopefully windsurfing-related.

No images, please.

"Secret" sites: as a matter of courtesy, if you talk about a site here on the list, please be willing to share the information (driving directions, hazards, wind patterns) needed to sail there.

When you *reply* to a message, remember that most mailers will reply to the whole mailing list rather than just the original author. If that is your intent, fine, but when sending a personal message, please remember to address the message to just that person.

=== How to post messages ===

To post to wind_talk, send e-mail to wind_talk@jr.hpl.hp.com.-DeleteThis

=== About the data ===

The windspeed data is reported in knots. It was formerly converted to mph, but that conflicted with the SFO phone, etc, so everything (except the Bay Area forecast) is now in knots. Pre-June92 data files I have stored are in mph, but all are marked with mph or knots.

You can get windspeed reports on demand - simply send a message to windreport@jr.hpl.hp.com-DeleteThis (the contents don't matter). The standard report will come by return e-mail. Please don't set this up for regular polling because that will load my workstation unduly. Problems to windspeed-request@jr.hpl.hp.com.-DeleteThis

=== Multiple mailings ===

Sometimes we get two mailings per hour. The reason is as follows. The primary network data source that supplies all the current readings (don't ask where) sometimes gets slow. My scripts retry, but the result is that data from this source is often 15-30 minutes after the hour.

I also have secondary sources, but the data there is watered down for use by "the public"; In particular, the wind direction is reduced to w, nw, n, etc. I dislike using this source for SFO because there is a big windsurfing difference between 260 and 290 degrees.

My compromise is to mail with the secondary data if the primary source does not come through by 14 minutes past the hour. You can tell these readings because the direction ends in "4" (indicating a resolution of 45 degrees in the direction). When the secondary source does come through, we get a second mailing with the better data.

=== Reporting locations ===

NWS and the FAA maintain separate weather operations at SFO. The FAA operates the 877-3585 "ATIS" recording, while NWS does the reports we get by network. They share the temperature and dewpt instruments, but for wind the NWS has one instrument near the intersection of the two main runway pairs, while FAA has 6 instruments around the runways. One other important difference is that FAA reports magnetic directions, while NWS reports true directions. To convert, add 17 degrees (rounded to 20, generally) to the FAA (phone) report to get true readings. The terminal forecasts use true directions as well.

The "SOSF" data in the network reports comes from South SF on San Bruno Mountain. I was told it is at 810 feet elevation (the ridge peak is at 1000-1200 feet) and at the nearer end of the ridge. It usually reads 2-3 knots higher than the meters at the airport.

There are broadcasts on 118.05 MHz every 30 seconds called "Shoreline Departure". This is apparently from the SOSF instrument. It requires an aircraft-band scanner to receive. The $20 Radio Shack aircraft radio can just barely get this from Coyote and 3rd Ave. Real (digital) scanners cost $100 (AC-powered) to ~$200-300 (walkie-talkie size); they can get this signal from at least as far south as Palo Alto.

For Palo Alto, use 120.600 MHz. For Moffett Field, use 283.000 MHz.

San_Luis_O is San Luis Obispo down the coast, not San Luis Reservoir. Travis_AFB is about 20 miles NW of Rio Vista and seems to have similar conditions to Rio.

"Oak_500mb" is the 500 millibar reading from the twice-a-day weather sounding balloons released from Oakland Airport. When the jetstream is overhead, this will show westerly around 50 knots, which tends to add some extra push to whatever surface pattern we have.

The Dread ASCII Graphics Map of the California Coast With Apologies to NOAA map MSC-9. '#' marks the points used to mark coastal forecast region boundaries. ---------------- CA - OR border -------------------- # Pt St George Crescent City 41.8 deg lat + + Eureka 40.8 + Cape Mendocino 40.4 + + Pt Cabrillo Ft Bragg 39.4 # Pt Arena 38.9 + Bodega Bay Santa Rosa 38.4 + Pt Reyes 38.0 + GG SF 37.7 + Pillar Pt Half Moon Bay 37.5 + San Jose 37.4 + Pigeon Pt 37.2 + Santa Cruz 37.0 # Pt Pinos Monterey 36.6 + Pt Sur 36.4 + + Pt Piedras Blancas 35.6 + San Luis Obispo 35.3 # Pt Sal Santa Maria 34.9 + Pt Conception Santa Barbara 34.5 +++++++++ + LA, etc 33.8 + ------ CA - Mex border 32.5

=== Examples of decoding the "cryptic comments" ===

SKY /CRYPTIC COMMENTS heights/100ft ----------------------------------- clr Clear clr /st w-n mdt cu e-se Clear, stratus west to north, moderate cumulus east to southeast 5 sct /fbnk w-n Scattered clouds at 500 feet, fogbank west to north 30 sct Scattered clouds at 3000 feet 30 -sct Thin scattered clouds at 3000 feet clr /h alqds Clear, haze all quadrants 7 sct 12 bkn Scattered clouds at 700 feet, broken clouds at 1200 clr /cu tcu omtns ne-e Clear, cumulus and towering cumulus over mountains northeast to east clr / k nw Clear, smoke northwest 35 sct 250 sct /mdt cu dsnt ne= Scattered clouds 3,500 feet, scattered 25,000, moderate cumulus distant northeast 15 -sct 40 -sct 120 -sct /k15 -sct cbs dsnt ne-e mdt cu dsnt s sw ag fire 3w few ac ne-s 1,500 thin scattered, 4,000 thin scattered, 12,000 thin scattered, smoke tops 1,500 feet, thin scattered cumulonimbus distant northeast through east, moderate cumulus distant south to southwest agricultural fire 3W?, few altocumulus northeast through south

=== Common wind patterns ===

A common pattern for good summer days is to have 5-10 knots W to NW during the night and morning, often with a lull around noon where the wind drops and shifts to N to NE. In the next two hours the wind will swing around to NW and pick up to 15 to 20 knots between 2 and 6 pm. If the sky is clear or low clouds are clearing, a good morning breeze (NW 8-10 knots) usually means a good afternoon wind.

When the marine clouds come far into the bay (e.g., morning overcast over the whole bay), SFO may remain under the clouds and have fairly mild wind readings (~~15 knots) all afternoon, but Coyote and 3rd can be cranking if they are beyond the clouds. This is most easily seen from the multi-city "sky" sections: if SFO is reporting *low* clouds (e.g, "9 sct" or "8 bkn") then it is under the marine clouds. If Hayward is clear, then the cloud line is somewhere over the Bay, and Coyote and 3rd are probably blowing hard. The clouds run in a stream only a couple of miles wide from SFO to Hayward; about the time the clouds get to Hayward the wind at Coyote and 3rd will shut off.

When we get very thick marine layers (more than 1500 feet), we will often get fog coming over the hills way down the peninsula. This often causes a west wind over much of the Peninsula, but may cut off Coyote (wrong direction for the NW-facing San Bruno gap, plus the wind is more diffused). This will generally show up as a SFO wind direction less than 290. Sometimes Oyster Point and Flying Tigers will blow in this case, and the winds can be higher than those recorded at SFO. 3rd Ave can also have significantly steadier winds. If the fog is coming over the hills as far south as Woodside, then Palo Alto is a good bet. Wind on the water is generally 2-5 knots more than that recorded at the Palo Alto airport.

I did some correlation experiments several years ago and concluded that the SFO-Stockton pressure differential was the best pressure to check at noon to predict afternoon SFO winds. My rule of thumb: -0.07 from SFO to Stockton is best. If the gradient is deeper, we tend to get fog coming over the whole Peninsula range, which gives us 10-15 knots everywhere. I.e., it feels "windy" in Palo Alto, but it's still only 10-15 knots at SFO and Coyote is actually worse.

My second indicator is SFO-Truckee or SFO-Tahoe - this should be less than +0.10 or so. More indicates high pressure in the Great Basin (east of the Sierras) which can lessen the suck from the California Central Valley.

Another good indicator is the marine layer depth, which I have just recently found a source for. A marine layer which is ~1000 feet deep and has a small Temp-DewPt value (less than 3 deg C) is ideal, as this fills the San Bruno gap, but does not flow over other parts of the Peninsula.

Depending on where the fog line is, other good locations may be Crissy or Berkeley. If the fog/clouds are coming well inland each night, Rio Vista and San Luis Res are generally good. These locations tend to crank up late in the afternoon (4 to 6 pm), blow all night and subside sometime mid-morning. They fairly often get over 25 knots.

In the winter, look for storms with good rotation. Before it hits, go to Half Moon Bay for flat-water sailing in the south winds. After it passes by, go to the usual summer spots (Coyote, 3rd, Crissy, etc) and sail in the clearing NW wind. All you get is 3-8 hours on either side, so you have to move quick. Sometimes we also get just a major W or NW jet-driven wind which can last longer.

=== Instrument readings vs wind at sailing sites ===

Winds near Coyote point typically are well correlated with SFO numbers. This is not surprising, since Coyote is just 3 miles downwind from SFO. The major gotcha is that there is a wind line caused by the southern edge of the San Bruno gap which is near the shore at Coyote for the typical direction of 290. Wind directions of 310 or more tend to bring the wind all the way to the shore. Directions less than 290 will decrease the wind at SFO somewhat, but they tend to move the wind line way offshore at Coyote, making the wind line a mile or two offshore for a direction of 270 or less. In these conditions, Coyote can be practically becalmed.

I think winds at Crown Sterling tend to follow the same pattern, but I don't sail there often enough to say for sure.

Winds in the channel at 3rd Ave are generally best correlated with the SoSF_SBrMt readings when the direction is 300 or more. This is the same instrument as the 118.05 MHz "shoreline departure" radio station, which is 800 feet up on San Bruno Mountain. The major exceptions occur when stratus clouds ("fog") get very close to the mountain - the readings get gusty as the clouds approach and they can drop quite a bit if the clouds completely envelop and pass San Bruno Mountain. You can tell when this happens because the temperature gets down within a few degrees of the SFO dewpoint temperature, usually about 55 F (the ocean temperature).

The direction at the San_Carlos station is useful for telling if the wind is blowing over the highway 92 pass by San Mateo. When 92 is blowing, San_Carlos reads about 280; when it is not, San_Carlos gets 330 to 020. This is about twice as much directional shift as we see at 3rd under these conditions. The windspeed at San_Carlos seems to be 3-10 knots less than at 3rd, so it is not very helpful.

For Tigers/Oyster, SoSF_SBrMt works well, especially on due west or slightly southwest. If it goes 320 or more northerly, it shuts down there.

Natural Bridges: Ed Scott wrote: > I use the Long Marine Lab sensor [for the Natural Bridges site], which > is on Ken's reports [as "NatBridges"], has a link through the Slug > Video cam, and is on the buoy reports on the COTW pager. If the COTW > sensor reads 11 or above, I check the LML sensor, and if it's blowing, > I go. I find that the COTW sensor [ on Ken's report as "cNatBridge"] > reads 10 lower than the actual conditions on a W or SW wind.

> If San Bruno is 280 or more, Candlestick rips. More southwesterly > winds (<280 at San Bruno) is better for Oyster Pt. and Flying Tigers. > On a west or southwest, Candlestick is blocked by San Bruno Mountain.

=== Tides and Hazards === These discussions use location-adjusted tide values.

The new tide program (xtide 1.2, Sep 95) seems to underestimate the tidal height at higher-than-usual low tides (which will lead to more water than expected).

The program also calculates "safe" times for 3rd and Palo Alto. These are chosen at pretty conservative levels: +2.5 for 3rd and +4.0 for Palo Alto. At these heights, I sail with no worries. At both sites I sail in as much as a foot less after reminding myself where the bars are. (One foot typically corresponds to 40-60 minutes time difference.)

Disclaimers: The calculated tide levels may be wrong, or the measured "safe" levels may be wrong. Sandbars shift, people leave anchors or other trash in shallow water. You might be sailing with a fin deeper than mine. A near-miss by an asteroid might produce an extra low tide. Lawyers may be lurking just below the water surface at any time, any place. Shit happens. So use your own judgement at all times and don't blame me if you hit something.

For sailing at Palo Alto, we used to need a tide level of at least 4 feet. With the new dock, 2.5 feet seems to be okay if you stay in the little harbor channel until you pass the downwind point. The "deep"-water channel runs right next to the white poles; everything else near the shore is mud flats at +1 to +2 feet. Hazards: there seems to be something hard at about +6.0 near the downwind point several hundred yards out.

Dumbarton Bridge: Take favorite route from 101 to dumbarton bridge (Marsh Rd., Willow Rd., or University Ave). when heading eastbound towards the highrise proper, you will see an exit for "ravenswood wildlife refuge" or somesuch to the right just before reaching the highrise. Take it and follow it parallel to the bridge. It goes under the highrise to the north side. Park there, that's where the launch is. Pretty obvious. There's a matching exit for Westbound traffic to use if you're coming from the east bay. I noticed during the extremely low morning tides the first week of Jul (there was water only in the channel itself) that there is some sort of small pile of debris on the western mudflats, about halfway between the western edge of the channel and the western shore, and maybe 2 hundred yds from the launch point at a 60deg angle from the longitudinal axis of the bridge. It's about the size and shape of a race car tube frame (?). I've never noticed it before and wonder if it is newly arrived. Anyway, it might be a problem when sailing in lowish conditions, but probably not when near high tide. It's the only noticable debris I've seen out there on the east or west flats btw.

For 3rd Ave, +3 feet is the safe limit for the old launch by the blue tanks (using the SM-adjusted tides, a little over +2 feet for GG height). At the new launch (fenced lot) +2.5 feet is fine. +2.0 feet is still okay for launching but is beginning to make hazards of the 4 sandbars between the launch and the channel. The bars are: 1) along the edge of the channel, from the channel marker towards the bridge - 0 ft near the marker, +1.5 ft near the bridge; 2) about halfway from the old launch to the channel marker - +1 ft; 3) two bars within 400 yards of the new launch, maybe 0 feet. These each stretch upwind starting approximately on a line between the new launch and the channel marker.

For Coyote Point, 0 feet is fine (you have to walk out 100 yards, but the mud is less than 6 inches deep). There was a recent report of a sandbar at about -1 feet just outside the swim area, however. There is also now a post broken off at about +1 ft, situated halfway between the two remaining posts on the side of the swimming area next to the launch beach. Another sailor reported a 1" pipe at a 45 degree angle, top at about +2.5 ft, about 3/4 of the way along the swim area and maybe 50 yards upwind from the poles (just downwind of a beam reach from the upwind corner of the swim area).

At Crown Sterling, 1 foot is enough to launch, but you need 2.5 feet to be clear of the sandbars. The main one lies across a line between the Crown Sterling launch and the pole in the water just south of the runway piers (this line is nearly directly across the usual wind). It sits about two thirds of the way from the shore to the pole, running roughly parallel to the wind direction, maybe half a mile long. The upwind end is at 0.0 feet, the downwind end is at +0.4 feet. There is another at around -0.5 ft around 100 feet upwind of the pole and another downwind of the pole (may be continuous). There is some other kind of obstruction at -1 to 0 ft further out along the same line. Near the shore, there is a pole with its top at +1.0 ft; it is 125 yards north of the hotel and 30 yards from the shore.

Mariott's requires at least +5 feet (SM-adjusted, or +4 GG) to launch.

Haskins Ave requires about +3 feet to launch.

Michael's Beach needs about 0 feet to launch.

In all the above locations, remember that there are often big rocks sitting on the bottom in otherwise just-barely-passable water. (Kirk broke an ankle that way.)

Oyster Point, Candlestick, Crissy field and Berkeley seem to have no problems at low tides.

Point Isabel is also pretty much always sailable. One must always pay attention to the submerged rocks near the access point, no matter what the tide level is. Also, the water can get pretty shallow near the opposite shore---the new housing development in Richmond.

At Powerlines (Sherman Island) some of the levee riprap at the launch openings goes under water at high tides, creating hazards if you sail too close (I broke a finbox this way).

At San Luis forebay, 219 feet is the danger level (it's pumped, not tidal). You *need* a weed fin later in the summer.

=== Site-specific etiquette ===

Fisherman at some locations have had their lines broken by too-close windsurfers. They asked that we not sail within 100 yards of any fishing areas - a reasonable request. The fishing areas I know of at sailing sites would include the pier at Candlestick, the pier at Oyster Pt, the point between Oyster Pt and Tigers, the pier at Crown Sterling and the point just north of the main beach at Coyote.

=== Mailing list additions and deletions ===

Send requests for mailing list additions and deletions to listserv@jr.hpl.hp.com.-DeleteThis (From HPdesk, use "'listserv'/hp1900/um(listserv@jr.hpl.hp.com-DeleteThis)") The legal commands are given below.

Everything appearing in [] below is optional; everything appearing in <> is mandatory.

Recognized requests are:

help [request] -------------- Without arguments, this file. Otherwise get specific information on the selected topic.

subscribe <list> <your name> ---------------------------- The only way to subscribe to a list.

unsubscribe <list> (or: signoff <list>) --------------------------------------- Remove yourself from the specified list.

which ----- Get a listing of discussion lists to which you have subscribed.

set <list> [<option> <value>] ----------------------------- Without the optional arguments, get a list of all current settings for the specified list. Otherwise change the option to the new value for that list.

recipients <list> (or: review <list>) ------------------------------------- Get a list of all people subscribed in the specified list.

information <list> ------------------ Get information about the specified list.

statistics <list> [subscriber email address(es)] ------------------------------------------------ Get a list of subscribers along with the number of messages each one of them has sent to the specified list. If the optional email addresses are given, then statistics will be collected for these users only.

lists ----- Get a list of discussion lists that are served by this server.

index [archive | path-to-archive] [/password] --------------------------------------------- Get a list of files in the selected archive, or the master archive if no archive was specified.

=== Files Available ===

You can get various files from the listserv by sending a message to listserv@jr.hpl.hp.com-DeleteThis with the message "get wind_talk <file>" where <file> is one of these:

file contents ---- ----------------- SFBA A description of the SF Boardsailing Association safety_guide The SFBA safety guide SF_info Kirk Lindstrom's FAQ for SF Bay sailing archive The whole wind_talk archive. 2 MB in 32 chunks of 66 KB. windspeed.info This information file - wind_* FAQ, plus misc SF Bay info

=== People ===

I sail mostly Coyote Point and 3rd Avenue; I wear a yellow helmet and a blue PFD; my blue Previa has Gorge Racks and license "KEN KATI". If you see me, say hi!

=== Other Electronic Windsurfing Forums ===

There is another windsurfing mailing list called windsurfing@fly.com-DeleteThis; this has a world-wide focus and readership. Send the message "help" to windsurfing-request@fly.com.-DeleteThis

For those with access to Usenet (network news), there is a newsgroup rec.windsurfing, also with global focus and readership.

=== Other Windsurf Weather Reporting Services ===

This windspeed data is available in various forms (the last is graphic) in these places: http://www.hpl.hp.com/personal/Ken_Poulton/windsurf.html http://and.com/BWR/BWR.html

There are two commercial services providing windsurfing reports for Northern

California:

Call of the Wind: A service that operates mainly via pagers and the web (or you can call individual windtalkers directly). The pagers carry current reports from their own set of windtalkers, plus some NWS airport and buoy sites and (nearly) daily forecasts. Call 1-800-WINDCALL or see http://www.windcall.com/ for info.

Windsight: You can get a pager, or you can get an account and call an 800 number to get information from a phone-menu system; they bill your account by the time on the phone. They carry forecasts, current reports from their own windtalkers and some NWS sites, and often a couple of condition reports from spotters at major sailing sites. See http://www.windsight.com or call 1-800-934-2278 for account info.

For all services, sensor location is a big issue. At locations such as Coyote, 3rd Ave and Crissy, the prevailing wind pattern has an offshore windline, leading to very different conditions on the water vs. on the beach.

=== History ===

In 1990, to check wind conditions we had to make phone calls to SFO or one of the windtalkers set up by the SFBA. Lots of phone calls! And lots of busy signals.

In 1991, Jonathan Hahn at NASA/Ames started an e-mail list for windsurfers, whose major content was of the form "Hey the 2:00 SFO report has 22 knots at [direction] 300. I'm going to Coyote [Point] !". I started sniffing around the net for sources of weather information and found a university site that had hourly weather condition reports available via telnet (no web browsers waaay back then :-). That source rather quickly caved in under the weight of too many users, but by then there was another source. Within a month or so I took over the mailing list since I was distributing the data. We soon separated it out into the 4 lists there are today.

The ways I get the data today include telnet, gopher and http; I have 4 or 5 different sources from which I collect data to make the hourly report I send out. The data is available in much sexier formats on several web pages, but the e-mail still seems to be a better fit for a large number of folks. Currently, we have about 300 subscribers during the summer.

=== Acknowledgements ===

Content-Type: message/rfc822

attached mail follows:

Message-ID: <199807281802.AA147378979@jr.hpl.hp.com-DeleteThis>
From: listproc@opus.hpl.hp.com-DeleteThis
Reply-To: listproc@opus.hpl.hp.com-DeleteThis
To: Stephen Hiley <SHiley@WSGC.com-DeleteThis>
Subject: HELP SET
Date: Tue, 28 Jul 1998 10:02:59 -0800
X-Mailer: Internet Mail Service (5.5.2448.0)
Content-Type: text/plain

Syntax: set <list> [<option> <arg[s]>] Without the optional arguments, get a list of all current settings for the specified list. Otherwise change the option to the new value for that list, as follows:

option can be: mail, password, address, conceal arg for mail can be: ack, noack, postpone, digest args for password have to be: current-password new-password args for address have to be: current-password new-address args for conceal can be: yes, no

'set <list>': get the current option settings for the list 'set <list> mail ack': your message is sent back to you 'set <list> mail noack': your message is not sent back to you 'set <list> mail postpone': no messages will be sent to you until you change mode again 'set <list> mail digest': your message is not sent back to you. New messages are not sent to you as they arrive, but are accumulated into digests that are periodically sent to you. 'set <list> password <current-password> <new-password>': change your password for live access to the system (i.e. for subscriber access privileges when telneting to the system). 'set <list> address <current-password> <new-address>: change the address you are subscribed with; may not be available on all lists. 'set <list> conceal yes': remove yourself from 'recipients' and 'statistics' listings. 'set <list> conceal no': opposite of previous mode.

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