df = pd.read_csv('t.csv')
max_df = df[['city', 'temperature']].groupby('city').max().reset_index()
pd.merge(max_df, df[['city', 'temperature', 'windspeed']], how='inner', on=['city', 'temperature'])

city_and_max_temp = data.groupby('city').agg('max')[['temperature']]
data.merge( right=city_and_max_temp ,how='inner')[['city','windspeed']]