Synoptic origin of early Autumn and late spring frostsin Yazd province

In this investigation by use of climatic methods of studies including statistical analisesand interpretations of synoptic plans and on the basis of daily data , absolute 28temperature of the station inside and neighboring area of yazd province in 10 yearsperiod of time between 1370 – 71 up to 1380 – 81 and according their equiralent mapshas been drawn and affer that by use of informations from ground level and 500hectopascal level maps , synoptic pattern of the case of over forward autumnal coldand spring late in yazd province has been classified on the basis of hand made andcluster methods .