How do I add the record of daily high and low temperature to the following code using 3d array and nested loop

// A c++ program that records the high and low temperatures for each day of all months
#include <iostream>
#include <string>

using namespace std;

//declare struct WeatherStats
/*struct is an user-defined data type available in C++.
It allows a user to combine data items of (possibly) different data types under a single name.*/
struct Weather{
    
    int highTemp;
    int lowTemp;
    double avgTemp;
};

//function Declaration
void Data(Weather&);
void Highest(const Weather[], const int);
void Lowest(const Weather[], const int);
double YearlyAvgTemp(const Weather[], const int);

// constant declaration
const int NUM_MONTHS = 12;

//a string array to get month names
string monthNames[NUM_MONTHS] = {"September", "October",
                                 "November", "December", "January", "February", "March",
                                 "April", "May", "June", "July",
                                 "August" };

int main()
{
    //define array of 12 WeatherStats structure variables
    Weather data[NUM_MONTHS];

    //get data for all months
    for(int i = 0; i < NUM_MONTHS; i++){
        cout << "Enter data for " << monthNames[i];
        cout << endl;
        Data(data[i]);
        cout << endl << endl;
    }

    //print the output

    Highest(data, NUM_MONTHS);
    Lowest(data, NUM_MONTHS);
    cout << "Yearly average temperature: ";
    cout << YearlyAvgTemp(data, NUM_MONTHS);


    return 0;
}

//function to read data into structure variables
//for a month
void Data(Weather& w){


    cout << "Enter high temperature: ";
    cin >> w.highTemp;

    //validate input using while loop
    while(w.highTemp < -100 || w.highTemp > 140){
        cout << "Enter a temperature within the range";
        cout << "[-100 to +140]: ";
        cin >> w.highTemp;
    }

    cout << "Enter low temperature: ";
    cin >> w.lowTemp;

    //validate input using while loop
    while(w.lowTemp < -100 || w.lowTemp > 140){
        cout << "Enter a temperature within the range";
        cout << "[-100 to +140]: ";
        cin >> w.lowTemp;
    }

    //calculate monthly average
    w.avgTemp = (w.lowTemp + w.highTemp) / 2.0;
}


//function to get yearly highest temperature
//and the month in which it occurred
void Highest(const Weather w[], const int numElements){
    //variables to aid the search
    int highIndex = 0, high = w[highIndex].highTemp;

    for(int i = 0; i < numElements; i++){
        if(w[i].highTemp > high){
            high = w[i].highTemp;
            highIndex = i;
        }
    }

    cout << "\nThe yearly highest temperature was " << high;
    cout << ", and it occurred in " << monthNames[highIndex] << endl;
}

//function to get yearly lowest temperature
//and the month in which it occurred
void Lowest(const Weather w[], const int numElements){
    //variables to aid the search
    int lowIndex = 0, low = w[lowIndex].lowTemp;

    for(int i = 0; i < numElements; i++){
        if(w[i].lowTemp < low){
            low = w[i].lowTemp;
            lowIndex = i;
        }
    }

    cout << "\nThe yearly lowest temperature was " << low;
    cout << ", and it occurred in " << monthNames[lowIndex] << endl;
}

double YearlyAvgTemp(const Weather w[], const int numElements){
    double total = 0, avg;

    for(int i = 0; i < numElements; i++)
        total += w[i].avgTemp;

    avg = (double)total/numElements;

    return avg;
}