Received: from zonker.hpl.hp.com by hpl-milo.hpl.hp.com with SMTP (15.11.1.3/15.5+IOS 3.14) id AA07802; Thu, 19 Aug 93 12:23:20 pdt Return-Path: <poulton@zonker.hpl.hp.com-DeleteThis> Received: by zonker.hpl.hp.com (1.37.187.4/15.5+IOS 3.14) id AA29250; Thu, 19 Aug 93 12:23:18 -0700 Date: Thu, 19 Aug 93 12:23:18 -0700 From: Ken Poulton <poulton@zonker.hpl.hp.com-DeleteThis> Message-Id: <9308191923.AA29250@zonker.hpl.hp.com-DeleteThis> To: windspeed@hpl-milo.hpl.hp.com-DeleteThis Subject: wind_talk
I have changed the policy on wind* list content a bit - mainly to
encourage discussion to be on the wind_talk list and not on the
wind_thresh and wind_afternoon lists. To this end, let me encourage
everyone interested to sign up on the wind_talk list - subscribe by
sending "subscribe wind_talk <first_name> <last_name>" to
listserv.jr.hpl.hp.com.
Ken Poulton
poulton@hpl-opus.hpl.hp.com-DeleteThis
"Don't hate yourself in the morning - sleep 'til noon."
... and then go sailing.
windspeed.info --- SF Bay Area wind/weather information by e-mail.
=== Windspeed mailing lists ===
Lists maintained by listserv@jr.hpl.hp.com-DeleteThis:
wind_afternoon People receiving automatic hourly wind reports from
noon to 6 pm daily.
wind_thresh People receiving automatic wind reports when the
wind is over 15 knots (during daylight hours).
wind_talk Discussion other than current wind reports.
You can send mail to any of the above addresses if you really want, but
in general, please mail your manual reports and messages to 'windspeed',
which sends mail to all of the above lists.
To unsubscribe, send mail to listserv@jr.hpl.hp.com-DeleteThis with the contents
"unsubscribe <list_name>". To subscribe, send mail with the contents
"subscribe <list_name> <first_name> <last_name>". For more info about
these mailings, the data and listserv, send "info <list_name>".
You can also get windspeed reports on demand - simply send a message
to windreport@milo.hpl.hp.com-DeleteThis (the contents don't matter).
=== Policy on what should be posted ===
For wind_thresh and wind_afternoon:
I (poulton@hplabsu.hpl.hp.com-DeleteThis) post hourly reports from the area
airports.
Any other current wind reports (e.g., from windtalkers) are
encouraged. Send these to "windspeed@jr.hpl.hp.com-DeleteThis" and they will
go to all three 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:
Whatever you want to say, hopefully windsurfing-related.
In all cases, think twice before sending a reply to the whole mailing
list. Many mailers will reply by default to the mailing list rather
than the original author.
=== About the data ===
The windspeed data is now reported in knots. It was formerly converted
to mph, but that conflicted with the SFO phone, etc, so everything
(except the Bay Area forecast, when that returns) 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 now - simply send a message
to windreport@milo.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@milo.hpl.hp.com.-DeleteThis
=== Reporting locations ===
NWS and the FAA maintain separate weather operations at SFO. The FAA
operates the 877-3585 "Avis" 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 report to get true readings.
The terminal forecasts use true directions as well.
The instrument on the pier closest to Coyote is apparently the one that
broadcasts new reports every 30 seconds on 118.045 MHz. This requires
nearly line-of-sight (and a scanner) to receive.
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.
San_Luis_O is San Luis Obispo down the coast, not San Luis Resevoir.
Travis_AFB is about 20 miles NW of Rio Vista and seems to have similar
conditions to Rio.
=== 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, 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.
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.
=== 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.
get <archive | path-to-archive> <file> [/password] [parts]
----------------------------------------------------------
Get the requested file from the specified archive. Certain subparts may
be obtained by specifying them as optional arguments.
release
-------
Get information about the current release of this listserv system.
=== People ===
I sail mostly Coyote Point and 3rd Avenue; I wear a yellow helmet
labelled "poulton@hplabs.hp.com-DeleteThis". If you see me, say hi!
=== Acknowledgements ===
Some of this data is made available courtesy of the National Science
Foundation-funded UNIDATA Project and the University of Michigan.
This archive was generated by hypermail 2b29 : Mon Dec 10 2001 - 02:27:00 PST