How to display welcome note in Wordpress along with user name?

The following piece of code full fill your requirement.

<?php
global $current_user;
get_currentuserinfo();
if(isset($current_user->user_login))
{
    $name=$current_user->user_login;
    echo 'Welcome '.ucfirst($name);
}
else
{

}
?>

......................
Keep Smilimg.