wmWeather-1.31/Src/GrabWeather

   1 #!/usr/bin/perl
   2
   3 #
   4 #    Grabs the latest local weather conditions from the National Weather Service (NWS).
   5 #    Uses the decoded METAR reports.
   6 #
   7 #    Need to give the 4-character METAR station code on the Command Line. E.g.;
   8 #
   9 #           GrabWeather KLAM
  10 #
  11
  12
  13     require "ctime.pl";
  14
  15
  16     #
  17     #  Change to users home directory. We used to dump into /tmp
  18     #  but using home dir instead avoids multiple users interfering
  19     #  with one another. (Yeah, we could "unique-ize" the filenames, but
  20     #  this is easier for now...)
  21     #
  22     $home = (getpwuid($<))[7];
  23     $ok = chdir() || chdir($home);
  24
  25
  26     #
  27     #  Check to see if .wmWeatherReports exists.
  28     #  If not, make it and move to it.
  29     #
  30     if ( !(-e ".wmWeatherReports") ){
  31         mkdir(".wmWeatherReports", 0775);
  32     }
  33     chdir(".wmWeatherReports");
  34
  35
  36
  37
  38
  39     $StationID    = $ARGV[0];
  40     $HTMLFileName = "$StationID.TXT";
  41     $URL          = "ftp://weather.noaa.gov/data/observations/metar/decoded/$HTMLFileName";
  42     $DataFileName = "$StationID.dat";
  43
  44
  45
  46
  47     #
  48     #  I think some of these wget command line options may cause problems
  49     #  for some people? Dont know why... (Perhaps they have a ~/.wgetrc file
  50     #  that overrides command line options?).
  51     #
  52     $GrabCmd = "wget --proxy=off --passive-ftp --tries 0 -q -O $home/.wmWeatherReports/$StationID.TXT $URL";
  53     system "$GrabCmd";
  54
  55
  56
  57
  58     #
  59     # Parse HTML File.
  60     #
  61     $Temp     = -999.0;
  62     $Chill    = -999.0;
  63     $DewPnt   = -999.0;
  64     $Pressure = -999.0;
  65     $Hum      = -999.0;
  66     $Flag = 0;
  67     open(TmpFile, "$HTMLFileName");
  68     while (<TmpFile>){
  69         chop;
  70         if ($Flag == 0) { $StationInfo = $_; };
  71         if ($Flag == 1) { $UpdateTime = $_; };
  72         if ($_ =~ /^Sky conditions:/ ){ $SkyConditions = $_; $SkyConditions =~ s/Sky conditions: (.*)/\1/; }
  73         if ($_ =~ /^Temperature:/ ){ $Temp = $_; $Temp =~ s/Temperature:\s*(\-{0,1}[0-9.]{1,}).*/\1/; }
  74         if ($_ =~ /^Windchill:/ ){ $Chill = $_; $Chill =~ s/Windchill:\s*(\-{0,1}[0-9.]{1,}).*/\1/; }
  75         if ($_ =~ /^Dew Point:/ ){ $DewPnt = $_; $DewPnt =~ s/Dew Point:\s*(\-{0,1}[0-9.]{1,}).*/\1/; }
  76         if ($_ =~ /^Pressure \(.*\):/ ){ $Pressure = $_; $Pressure =~ s/Pressure \(.*\):\s*([0-9.]{2,}).*/\1/; }
  77         if ($_ =~ /^Relative Humidity:/ ){ $Hum = $_; $Hum =~ s/Relative Humidity:\s*(\d{1,})\%.*/\1/; }
  78         if ($_ =~ /^ob: / ){ $CodedMETAR = $_; $CodedMETAR =~ s/ob: (.*)/\1/; }
  79         ++$Flag;
  80     }
  81     close(TmpFile);
  82
  83
  84
  85
  86     #
  87     #  Isolate the Wind groups out of the coded METAR report.
  88     #  There may be two groups - the normal one and a variability set.
  89     #
  90     $WindGroup = $CodedMETAR;
  91     $WindGroup =~ s/ RMK\s.*$//;
  92     $VarWindGroup = $WindGroup;
  93
  94
  95     if ($WindGroup =~ /.*\s\w{3}\d{2,3}KT\s\d{3}V\d{3}\s.*/ ) {
  96         $VarWindGroup =~ s/.*\s\w{3}\d{2,3}KT\s(\d{3}V\d{3})\s.*/\1/;
  97         $VarFlag = 1;
  98     } elsif ($WindGroup =~ /.*\s\w{3}\d{2,3}MPS\s\d{3}V\d{3}\s.*/ ) {
  99         $VarWindGroup =~ s/.*\s\w{3}\d{2,3}MPS\s(\d{3}V\d{3})\s.*/\1/;
 100         $VarFlag = 1;
 101     } elsif ($WindGroup =~ /.*\s\w{3}\d{2,3}G\d{2,3}KT\s(\d{2,3}V\d{2,3})\s.*/ ) {
 102         $VarWindGroup =~ s/.*\s\w{3}\d{2,3}G\d{2,3}KT\s(\d{2,3}V\d{2,3})\s.*/\1/;
 103         $VarFlag = 1;
 104     } elsif ($WindGroup =~ /.*\s\w{3}\d{2,3}G\d{2,3}MPS\s(\d{2,3}V\d{2,3})\s.*/ ) {
 105         $VarWindGroup =~ s/.*\s\w{3}\d{2,3}G\d{2,3}MPS\s(\d{2,3}V\d{2,3})\s.*/\1/;
 106         $VarFlag = 1;
 107     } else {
 108         $VarWindGroup = "";
 109         $VarFlag = 0;
 110     }
 111     $Direction1 = $VarWindGroup; $Direction1 =~ s/(\d{3})V\d{3}/\1/;
 112     $Direction2 = $VarWindGroup; $Direction2 =~ s/\d{3}V(\d{3})/\1/;
 113
 114
 115
 116     $GustFlag = 0;
 117     if ($WindGroup =~ /.*\s\w{3}\d{2,3}KT\s.*/ ) {
 118         $WindGroup =~ s/.*\s(\w{3}\d{2,3}KT)\s.*/\1/;
 119         $Direction = $WindGroup; $Direction =~ s/(\w{3})\d{2,3}KT/\1/;
 120         $Speed = $WindGroup; $Speed =~ s/\w{3}(\d{2,3})KT/\1/;
 121     } elsif ($WindGroup =~ /.*\s\w{3}\d{2,3}MPS\s.*/ ) {
 122         $WindGroup =~ s/.*\s(\w{3}\d{2,3}MPS)\s.*/\1/;
 123         $Direction = $WindGroup; $Direction =~ s/(\w{3})\d{2,3}MPS/\1/;
 124         $Speed = $WindGroup; $Speed =~ s/\w{3}(\d{2,3})MPS/\1/;
 125         $Speed *= 1.942;
 126     } elsif ($WindGroup =~ /.*\s\w{3}\d{2,3}G\d{2,3}KT\s.*/ ) {
 127         $WindGroup =~ s/.*\s(\w{3}\d{2,3}G\d{2,3}KT)\s.*/\1/;
 128         $Direction = $WindGroup; $Direction =~ s/(\w{3})\d{2,3}G\d{2,3}KT/\1/;
 129         $Speed1 = $WindGroup; $Speed1 =~ s/\w{3}(\d{2,3})G\d{2,3}KT/\1/;
 130         $Speed2 = $WindGroup; $Speed2 =~ s/\w{3}\d{2,3}G(\d{2,3})KT/\1/;
 131         $GustFlag = 1;
 132     } elsif ($WindGroup =~ /.*\s\w{3}\d{2,3}G\d{2,3}MPS\s.*/ ) {
 133         $WindGroup =~ s/.*\s(\w{3}\d{2,3}G\d{2,3}MPS)\s.*/\1/;
 134         $Direction = $WindGroup; $Direction =~ s/(\w{3})\d{2,3}G\d{2,3}MPS/\1/;
 135         $Speed1 = $WindGroup; $Speed1 =~ s/\w{3}(\d{2,3})G\d{2,3}MPS/\1/;
 136         $Speed2 = $WindGroup; $Speed2 =~ s/\w{3}\d{2,3}G(\d{2,3})MPS/\1/;
 137         $Speed1 *= 1.942; $Speed2 *= 1.942;
 138         $GustFlag = 1;
 139     } else {
 140         $WindGroup = "";
 141     }
 142
 143
 144
 145     #
 146     #  Get the Time out of the coded Metar Report.
 147     #
 148     $UniversalTime = $CodedMETAR;
 149     if ($UniversalTime =~ /$StationID \d{1,2}\d{2}\d{2}Z/ ){
 150
 151         $UniversalTime =~ s/$StationID (\d{1,2})(\d{2})(\d{2})Z .*/\2:\3/;
 152
 153     } else {
 154
 155         $UniversalTime = "99:99";
 156
 157     }
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167     #
 168     #  Write out the stuff we need to the Data File. This is the file that will
 169     #  be read by wmWeather.
 170     #
 171     if ($Flag > 0){
 172         open(TmpFile, ">$DataFileName");
 173         print TmpFile "$StationInfo\n";
 174         print TmpFile "$UpdateTime\n";
 175         print TmpFile "$SkyConditions\n";
 176         print TmpFile "$UniversalTime\n";
 177         print TmpFile "$Temp\n";
 178         print TmpFile "$DewPnt\n";
 179         print TmpFile "$Chill\n";
 180         print TmpFile "$Pressure\n";
 181         print TmpFile "$Hum\n";
 182
 183         if ($Direction eq "" ){
 184             print TmpFile "-9999\n";
 185         } elsif ($Direction =~ /VRB/ ){
 186             print TmpFile "999\n";
 187         } elsif ($VarFlag) {
 188             $Direction += 0;
 189             print TmpFile "-$Direction\n";
 190         } else {
 191             $Direction += 0;
 192             print TmpFile "$Direction\n";
 193         }
 194
 195         if ($WindGroup eq "" ) {
 196             print TmpFile "-9999\n";
 197         } elsif ($GustFlag) {
 198             $AvgSpeed = ($Speed1 + $Speed2)/2.0;
 199             $AvgSpeed *= 1.15155;
 200             print TmpFile "-$AvgSpeed\n";
 201         } else {
 202             $Speed += 0;
 203             $Speed *= 1.15155;
 204             print TmpFile "$Speed\n";
 205         }
 206
 207         close(TmpFile);
 208     }
 209
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 212