Show local time on spc.nws.gov

index.js

// ==UserScript==
// @name         NWS Thunderstorm outloook; Show local time
// @namespace    http://tampermonkey.net/
// @version      2024-04-26
// @description  The NWS provides great maps! Their web interface needs help.
// @author       You
// @match        https://www.spc.noaa.gov/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=noaa.gov
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    document.querySelectorAll('#elements td').forEach(el => {
      let matcher = el.textContent.match(/\d\d/g),
          start = matcher[0],
          end = matcher[1],
          times = []

      if(start && end) {
        times[0] = new Date(); times[0].setUTCHours(start)
        times[1] = new Date(); times[1].setUTCHours(end)

        el.querySelector('a').textContent = `${times[0].getHours()}L-${times[1].getHours()}L`
      }


    })

})();