Comparing the effect of climate condition on tourism calendar in arid and humid cities using Holiday Climate Index (HCI) (Case Study: Isfahan and Rasht)

     Climatic conditions have a major influence in attracting tourists to a city in different months. In this study, the potential of Isfahan and Rasht as arid and humid cities, respectively, was investigated in terms of attracting tourists during a year. For this purpose, the Holiday Climate Index (HCI), which has been designed based on daily climate information, was used. The results showed that in Isfahan, with rising air temperature and reducing air humidity in March, April and May, the mean value of HCI is more than 69 and climatic condition is "very good". Also, from September 14, the value of HCI reaches above 69 and shows "very good" condition and this condition continues until the end of October. Therefore, these two periods are the best times for presence of tourists in Isfahan. In Rasht, in April and May, because of climate variables suitability (sunshine hours, cloudiness, and weather temperature) in comparison to other months, the mean value of HCI is equal to 66 (acceptable). It seems that the stable climate condition and therefore HCI value provide a suitable period for tourism in Rasht. In other months, because of high humidity and precipitation, the value of HCI is less than 60.