Regular expression issue

[dmbkiwi at gmail.com]

I'm trying to parse a line of html as follows:

<td style="width:20%" align="left">101.120:( KPA (-)</td>
<td style="width:35%" align="left">Snow on Ground)0 </td>

however, sometimes it looks like this:

<td style="width:20%" align="left">N/A</td>
<td style="width:35%" align="left">Snow on Ground)0 </td>


I want to get either the numerical value 101.120 (which could be a
different number depending on the data that's been fed into the page,
or in terms of the second option, 'N/A'.

The regexp I'm using is:

.*?Pressure.*?"left">(?P<baro>\d+?|N/A)</td>|\sKPA.*?Snow\son\sGround

Can someone help me debug this.  It's not picking up the number, and
I'm not sure I've got the syntax for '|' right, but can't find a
detailed tutorial on how to use |.

Any help would be appreciated.

Thanks

Matt