JSFiddle - React, Tailwind, and code Playground

HTML

<div id="wrapper">
    <div id="loader"></div>
    <div id="content"></div>
</div>

JavaScript

$(function () {
    
    var series = [], // Your series array
        loader = $('#loader'), // UI loader sample
        request = {}; // Request params
    
    /**
     * Set request method, url and data if needed
     * In this case I am sending an object with a text property
     * that will be returned from jsfiddle "echo" service
     */
    request.method = 'GET';
    request.url = '/echo/jsonp/';
    request.data = {
        text: 'Second message returned from "echo" service'
    };

    // Send ajax call
    retrieveData(request, series, handleData);
    
    // Set loading message to UI
    loader.html('Loading...');
    
    // Just do some logging to know how process goes
    console.log('Populating series for first time');
    
    /** 
     * Populate series for first time, at this point process
     * will go on and after the response from server was finally
     * done, process will go to the callback (since ajax calls 
     * are async).
     */
    populate(series);
    
    // Just do some logging to know how process goes
    console.log('End populating series for first time');
});

function populate(series) {
    var dummy = {
        text: 'First message populated over process'
    };
    
    // Set dummy object to series array
    series.push(dummy);
};

/**
 * Used to make ajax call and return data from server
 */
function retrieveData(cfg, series, callback) {
    $.ajax({
        type: cfg.method,
        url: cfg.url,
        data: cfg.data
     }).done(function(data, status, xhr) {
        // Pass args to callback function if defined
        if (callback) callback(series, data);
     }).fail(function(xhr, status) {
        /**
         * Pass args to callback function if defined
         * At this point, request wasn't success so 
         * force data arg at callback to be 'null'
         */
        if (callback) callback(series, null);
     });
};

/**
 * Used to handle data returned from server
 * Note: Your series array can be...