Localizing to Post Locations

I’m working on a similar situation that may be of some use, I have towns set as a custom taxonomy term.

Basically you have to create a custom function and hook it into your theme where you want it to display: (I’m using Genesis)

//* Output location specific weather
add_action('genesis_before_content','my_localized_weather');
function my_localized_weather(){
if(has_term( 'seattle', 'local-info' )){ //checks if seattle is in my local-info taxonomy.
	$town = 'Seattle';
echo do_shortcode("[wunderground location='$town, WA' numdays='3' layout='simple']"); //All the towns will be in WA so I don't need to modify the state.
}
}
//This function will only work for one city, so it will need modification to work for all cities that I want to check, but it is a starting point.

So, if you want to use a custom field you would have to check the meta, and dynamically set a string in the shortcode… something like this (untested):

add_action('your_theme_hook','my_localized_weather');
function my_localized_weather(){
$my_city = get_post_meta($post->ID, 'city-field', true); //if your meta field is called: city-field
    if ( ! empty ( $my_city ) ) {
   echo do_shortcode("[wunderground location='$my_city, WA' numdays='3' layout='simple']");
//as long as $my_city has your city this will work.
//if your state is WA, otherwise run another meta check to pull in the state name.

}
}