use strict;
use warnings;
use Data::Dumper;
use HTML::TreeBuilder;

my $h = HTML::TreeBuilder->new;
$h->parse_content( do{ local $/; <DATA> } );

my (@tmp,@tds);
for (map $_->as_HTML, $h->look_down( class => qr/Alt(Warning|Error)/ )) {
    if (/^<tr/) {
        if (@tmp) {
            push @tds, [@tmp]; 
            @tmp = ();
        }
    } else {
        push @tmp, $_;
    }
}
push @tds, [@tmp] if @tmp; 
print Dumper \@tds;

__DATA__
<TABLE class=HeaderFrame height=100 cellSpacing=0 cols=3 cellPadding=0 width="100%" border=0 align="left">
  <TR vAlign=top height=100>
    <TD vAlign=top width="100%" height="100">
      <DIV style="overflow: auto; width: "100%"; height: 200; valign: top">
      <TABLE cellSpacing=0 cols=4 cellPadding=0 width="100%" border=0 height="100">
        <TR height=25 nowrap>
          <TD class=HeaderTitleNoVLine height="14" width="10">&nbsp;</TD>
          <TD class=HeaderTitle noWrap align=left height="14">Status</TD>
          <TD class=HeaderTitle noWrap align=left height="14">Results</TD>
          <TD class=HeaderTitle noWrap align=left height="14">Schedule Start</TD>
          <TD class=HeaderTitle noWrap align=left height="14">Actual Start</TD>
          <TD class=HeaderTitle noWrap align=left height="14">Schedule Name</TD>
          <TD class=HeaderTitle noWrap align=left height="14">Node Name</TD>
          <TD class=HeaderTitle noWrap align=left height="14">Domain Name</TD></TR>
                 <TR class=AltLight height=22>
          <TD class=AltLightNoVline align=middle height="17" width="10"> </TD>
          <TD class=AltLight align=left height="17">Completed</TD>
          <TD class=AltLight align=left height="17">Successful</TD>
          <TD class=AltLight align=left height="17">2015-05-11-17.00</TD>
          <TD class=AltLight align=left height="17">2015-05-11-17.10</TD>
          <TD class=AltLight align=left height="17">DAILYBACKUP_5PM</TD>
          <TD class=AltLight align=left height="17">ServerA</TD>
          <TD class=AltLight align=left height="17">ST10_DOMAIN</TD></TR>
                  <TR class=AltWarning height=22>
          <TD class=AltWarningNoVline align=middle height="17" width="10"> </TD>
          <TD class=AltWarning align=left height="17">Missed</TD>
          <TD class=AltWarning align=left height="17"></TD>
          <TD class=AltWarning align=left height="17">2015-05-11-18.00</TD>
          <TD class=AltWarning align=left height="17"></TD>
          <TD class=AltWarning align=left height="17">DAILYBACKUP_6PM</TD>
          <TD class=AltWarning align=left height="17">ServerB</TD>
          <TD class=AltWarning align=left height="17">ST10_DOMAIN</TD></TR>
        <TR class=AltWarning height=22>
          <TD class=AltWarningNoVline align=middle height="17" width="10"> </TD>
          <TD class=AltWarning align=left height="17">Missed</TD>
          <TD class=AltWarning align=left height="17"></TD>
          <TD class=AltWarning align=left height="17">2015-05-11-18.00</TD>
          <TD class=AltWarning align=left height="17"></TD>
          <TD class=AltWarning align=left height="17">NJDLYBACKUP_6PM</TD>
          <TD class=AltWarning align=left height="17">ServerC</TD>
          <TD class=AltWarning align=left height="17">ST13_DOMAIN</TD></TR>
                  <TR class=AltDark height=22>
          <TD class=AltDarkNoVline align=middle height="17" width="10"> </TD>
          <TD class=AltDark align=left height="17">QATSWAS85</TD>
          <TD class=AltDark align=left height="17">37899</TD>
          <TD class=AltDark align=left height="17">104,113</TD>
          <TD class=AltDark align=left height="17">617</TD>
          <TD class=AltDark align=left height="17">0</TD>
          <TD class=AltDark align=left height="17">0</TD>
          <TD class=AltDark align=left height="17">0</TD>
          <TD class=AltDark align=left height="17">25</TD>
          <TD class=AltDark align=left height="17">13</TD>
          <TD class=AltDark align=left nowrap height="17">251.30 MB</TD>
          <TD class=AltDark align=left height="17">00:00:58</TD>
          <TD class=AltDark align=left height="17">4,378.98</TD>
          <TD class=AltDark align=left height="17">0%</TD>
        </TR>
        <TR class=AltLight height=22>
          <TD class=AltLightNoVline align=middle height="17" width="10"> </TD>
          <TD class=AltLight align=left height="17">ServerD</TD>
          <TD class=AltLight align=left height="17">38048</TD>
          <TD class=AltLight align=left height="17">31,461</TD>
          <TD class=AltLight align=left height="17">51</TD>
          <TD class=AltLight align=left height="17">0</TD>
          <TD class=AltLight align=left height="17">0</TD>
          <TD class=AltLight align=left height="17">0</TD>
          <TD class=AltLight align=left height="17">2</TD>
          <TD class=AltLight align=left height="17">2</TD>
          <TD class=AltLight align=left nowrap height="17">24.14 MB</TD>
          <TD class=AltLight align=left height="17">00:00:12</TD>
          <TD class=AltLight align=left height="17">1,946.00</TD>
          <TD class=AltLight align=left height="17">0%</TD>
        </TR>
</TABLE> </DIV></TD>
  </TR></TABLE>