Null pointer exception when pressing 7 days button?

package com.example.abhishek.stormy.weather;

import android.os.Parcel;
import android.os.Parcelable;

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.TimeZone;

/**
 * Created by Abhishek on 11-05-2015.
 */
public class Day implements Parcelable {
    private long mTime;
    private String mSummary;
    private double mTemperatureMax;
    private String mIcon;
    private String mTimezone;

    public long getTime() {
        return mTime;
    }

    public void setTime(long time) {
        mTime = time;
    }

    public String getSummary() {
        return mSummary;
    }

    public void setSummary(String summary) {
        mSummary = summary;
    }

    public int getTemperatureMax() {
        return (int)Math.round(mTemperatureMax);
    }

    public void setTemperatureMax(double temperatureMax) {
        mTemperatureMax = temperatureMax;
    }

    public String getIcon() {
        return mIcon;
    }

    public void setIcon(String icon) {
        mIcon = icon;
    }

    public String getTimezone() {
        return mTimezone;
    }

    public void setTimezone(String timezone) {
        mTimezone = timezone;
    }

    public int getIconId() {
        return Forecast.getIconId(mIcon);
    }

    public String getDayOfTheWeek() {
        SimpleDateFormat formatter = new SimpleDateFormat("EEEE");
        formatter.setTimeZone(TimeZone.getTimeZone(mTimezone));
        Date dateTime = new Date(mTime * 1000);
        return formatter.format(dateTime);
    }

    @Override
    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeLong(mTime);
        dest.writeString(mSummary);
        dest.writeDouble(mTemperatureMax);
        dest.writeString(mIcon);
        dest.writeString(mTimezone);
    }

    private Day(Parcel in) {
        mTime = in.readLong();
        mSummary = in.readString();
        mTemperatureMax = in.readDouble();
        mIcon = in.readString();
        mTimezone = in.readString();
    }

    public Day() { }

    public static final Creator<Day> CREATOR = new Creator<Day>() {
        @Override
        public Day createFromParcel(Parcel source) {
            return new Day(source);
        }

        @Override
        public Day[] newArray(int size) {
            return new Day[size];
        }
    };
}

package com.example.abhishek.stormy.ui;

import android.app.ListActivity;
import android.content.Intent;
import android.os.Parcelable;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ArrayAdapter;

import com.example.abhishek.stormy.R;
import com.example.abhishek.stormy.adapters.DayAdapter;
import com.example.abhishek.stormy.weather.Day;

import java.util.Arrays;

public class DailyForecastActivity extends ListActivity {

    private Day[] mDays;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_daily_forecast);

        Intent intent = getIntent();
        Parcelable[] parcelables = intent.getParcelableArrayExtra(MainActivity.DAILY_FORECAST);
        mDays = Arrays.copyOf(parcelables, parcelables.length, Day[].class);

        DayAdapter adapter = new DayAdapter(this, mDays);
        setListAdapter(adapter);
    }
}

package com.example.abhishek.stormy.adapters;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import com.example.abhishek.stormy.R;
import com.example.abhishek.stormy.weather.Day;

/**
 * Created by Abhishek on 16-05-2015.
 */
public class DayAdapter extends BaseAdapter {

    private Context mContext;
    private Day[] mDays;

    public DayAdapter(Context context, Day[] days){
        mContext = context;
        mDays =days;
    }

    @Override
    public int getCount() {
        return mDays.length;
    }

    @Override
    public Object getItem(int position) {
        return mDays[position];
    }

    @Override
    public long getItemId(int position) {
        return 0; // we arent going to use this. Tag items for easy reference
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;

        if(convertView == null){
            //brand new
            convertView = LayoutInflater.from(mContext).inflate(R.layout.daily_list_item,null);
            holder = new ViewHolder();
            holder.iconImageView = (ImageView)convertView.findViewById(R.id.iconImageView);
            holder.temperatureLabel = (TextView)convertView.findViewById(R.id.temperatureLabel);
            holder.dayLabel = (TextView) convertView.findViewById(R.id.dayNameLabel);

            convertView.setTag(holder);
        }else{
            holder = (ViewHolder)convertView.getTag();
        }

        Day day = mDays[position];

        holder.iconImageView.setImageResource(day.getIconId());
        holder.temperatureLabel.setText(day.getTemperatureMax() + "");
        holder.dayLabel.setText(day.getDayOfTheWeek());

        return convertView;
    }

    private static class ViewHolder{
        ImageView iconImageView; //public by default
        TextView temperatureLabel;
        TextView dayLabel;
    }
}