wunderground_banner_remove.user.js

// ==UserScript==
// @name         Wunderground Remove Banner
// @namespace    https://github.com/RyanBreaker
// @version      0.2
// @description  Removes annoying ad banner from the top of wunderground.com.
// @author       Ryan Breaker
// @include      *wunderground.com/*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';
    
    var el = document.getElementsByClassName('header-ad-wrap')[0];
    if (el !== undefined) {
        el.remove();
        console.log('Banner removed');
    } else {
        console.log('Banner not found');
    }
})();