Weather statistics using structure

[prettyknitty]

I have been working on this for awhile, but I was hoping to get input from someone with more experience.
I have to stick with the structure and enum format for the assignment, but I was wondering if anyone had any opinions on the way the high/low temperature sections should be done?
Thanks for your help, I appreciate any hints.

#include <iostream>
#include <string>
#include <iomanip>

using namespace std;

struct WeatherInfo
{
    double rainfall;
    double highTemp;
    double lowTemp;
 };

enum Month {January, February, March, April,
                May, June, July, August,
                September, October, November, December};


int main()
 {
    const int MONTHS = 3;
    WeatherInfo month[MONTHS];
    int index;

    double rainTotal = 0.0;
    double tempTotal = 0.0;
    double tempHigh = 0.0;
    double tempLow = 0.0;

    for (index = January; index <= March; index = static_cast<Month>(index +1))
     { 
        cout << "Please enter the rainfall in inches";
        cout << (index + 1) << " :";
        cin >> month[index].rainfall;
        rainTotal += month[index].rainfall;

        cout << "Please enter the temperature";
        cout << (index + 1) << " :";
        cin >> tempTotal;

            if ( tempTotal < -100 || tempTotal > 140) 
            { 
                cout << "The temperature you entered is invalid" << endl; 
                cout << "Please re-enter: "; 
                cin >> tempTotal; 
            } 

            if (month[index] > tempTotal)
        {
            tempHigh += month[index].highTemp;
        }

         if (month[index] < tempTotal)
        {
            tempLow += month[index].lowTemp;
        }

    }

    cout << "The total rainfall for the year is " << rainTotal << endl; 
    cout << "The highest temperature is " << tempHigh << endl;
    cout << "The lowest temperature is " << tempLow << endl;

return 0;

}

[kal_crazy]

From what I see line 48 and line 53 would have an error. And you're not really comparing values. Also you're adding up the high/low temperatures instead of just storing it if a temperature is lower or higher than the input.