.TH WEATHER 7
.SH NAME
map, key, plot, photo, movie, report, query, wextract, iupdate  \- weather maps, reports, photos, and utilities
.SH SYNOPSIS
.PP
.B weather/photo
[
.B vis | ir
]
.PP
.B weather/movie
[
.B vis
|
.B ir
]
[
.I nobs
]
.PP
.B weather/map
[
.B us
|
.B us24
|
.B nyc
|
.B colo
|
.B dc
|
.B eur
|
.B jap
|
.B radar
]
.PP
.B weather/key
.PP
.B weather/query
.PP
.B weather/plot
[
.I wextract-options
]
[
.I map-location
]
[
.B -r dn
]
[
.B radar
]
.PP
.B weather/report
[
.I wextract-options
]
[
.B quake summary
]
.PP
.B /bin/aux/wextract
[
.I wextract-options
]
.PP
.B /bin/aux/iupdate
[
.B -i
.I yyyymm
]
.PP
.SH DESCRIPTION
.I Weather/map
displays the latest available national weather map, including precipitation,
isobars, fronts, and wind information.  The map is updated three
times a day.
.I Weather/key 
displays a reference chart for the symbols in
.IR weather/map .
.PP
.I Weather/photo
fetches and displays the latest satellite photographs.  
Visible and infrared photographs are selected with 
.B vis
and
.B ir
respectively.  
.B Ir 
is the default.
In infrared photos, hotter objects are blacker.
The maps and photos are obtained from
.B vmd.cso.uiuc.edu
which updates them hourly (except 
visible maps during the hours of darkness) across the entire
US.
The National Weather Service data is made available courtesy of the National
Science Foundation-funded UNIDATA Project and the University of Michigan.
.PP
.I Weather/movie
displays the last
.I nobs
(default 72) weather photos in a loop at five frames per
second.  Infrared photos are default.
.PP
.I Weather/query
connects to the Weather Underground server at the University of
Michigan.  This is an interactive menu system providing access
to a variety of weather information, including forecasts.
.PP
.I Weather/plot
plots a weather map.
`Radar' displays the precipitation intensities reported in selected time
period.
The echoes range from 1 (light) to 6 (severe).
Snow produces weaker reflections than
rain.  The
.B -r
option selects the radar display symbols:
.B d
for various size dots,
.B n
for numbers.
The default is various shaded circles.  For terminals with 1-bit deep
bitmaps, the 
.B d
option is default.
Radar information is not available outside the US.
The time period for the reported information is controlled by
.I wextract-options
(See below.)
The default is the previous 60 minutes.
.PP
.I Map-location
selects the area to be displayed:
.TF summary
.TP
.B "e ne se gulf us"
Parts of the US.  Default is
.BR e .
.TP
.BI -L " lat1 lat2 long1 long2"
Specific latitude and longitude pairs.
.PD
.RE
.IP
.PP
.I Weather/report
extracts various reports.  Available reports are:
.TF summary
.TP
.B summary
A chatty summary of the national weather. Default shows all weather
summaries for the last 24 hours.
.TP
.B quake
Earthquake reports.  Default displays all earthquake reports for the
last 72 hours.
.PD
.RE
.IP
.PP
.I Iupdate
scans
.B /lib/weather/raw
and updates
.BR /lib/weather/raw.idx .
This file provides the year and month information (which the 
.B raw
data lacks)
and greatly speeds the processing
of the huge
.B raw
file.
If the raw file is restarted,
the
.BI -i yyyymm
option recreates the index file.  
.I Yyyymm
is the year and month of the first record in the raw file.
.PP
.I Wextract
prints selected parts of the
.B raw
file based on time and record type.
.I Wextract-options
are:
.TF " record-type,..."
.TP
.BI -a " age"
Maximum age of records before selected time.  Default is 1 day.
.TP
.BI -d " enddate"
Date and time of the last record accepted.  Default is the present.
Dates may be relative to the current time, or an absolute time.
Relative dates begin with a minus and have the form
.RI [\- days .] hours [: minutes ]
Absolute times have the form
[[[\fIyear\fR/]\fImonth\fR/]\fIday\fR.]\fIhour\fR[:\fIminute\fR][\fITZ\fR]
where
.I year
is a four digit number and
.I TZ
is
.B Z
for GMT or a three-letter time zone identifier.
.TP
.BI -t " record-type,..."
Types of records selected.
Each record in the raw weather file has a three digit type.  A record type
may be a string of these numbers, or a record name.
The records in the FAA-supplied
.B raw
file are not documented.  A listing of the record names
appears in the source listing for 
.IR wextract .
Some record types are:
.TF "   unknown"
.TP
.B "   sd"
Encoded precipitation radar data.
.TP
.B "   wa"
AIRMETS for pilots.
.TP
.B "   ws"
Convective SIGMETS for pilots.
.TP
.B "   unknown"
All records not in one of the named types, plus malformed records.
.TP
.B "   all"
All records.
.PD
.RE
.IP
.SH FILES
.TF /lib/weather/raw.idx
.TP
.B /lib/weather/raw
The raw weather data straight off the wire since early June, 1990.
.TP
.B /lib/weather/raw.idx
An hourly index into 
.BR /lib/weather/raw .
.SH "SEE ALSO"
.IR map (7), 
.IR plot (1).
.PP
.SH BUGS
Network vagaries and problems on the source machines may make
.IR weather/photo ,
.IR weather/query ,
and
.I weather/map
unavailable or outdated.
.PP
The satellite photographs the east coast at an oblique angle.
.PP
.I Iupdate 
and
.I wextract
can be slow when the data is WORM-resident, which is likely.
Absolute times don't handle time zones correctly.
Much of the raw file is a mystery.
.PP
The rain echo intensities on
.I weather/map
do not monotonically darken with increasing precipitation on
monochrome displays.