The Mt. Washington Icing Sensor Project (MWISP) field campaign was conducted in April 1999 to gather remotely sensed and in situ data for the purpose of trying to "see" areas of aircraft icing potential. The initial synoptic weather study by Markle et al. (2000) concentrated on the month of April, but also gathered information on March. They found that April 1999 was an anomalous month for the region, due to higher than normal occurrences of certain synoptic patterns unfavorable for aircraft icing when compared to the most April months of the previous 44 years. The current study continues the methodology of that previous study and extends it to cover all the months from 1955 through 1999 in order to develop detailed monthly synoptic climatologies and variations for Mt. Washington region. The climatologies will also be analyzed in the context of icing potential.

The team used NCAR/NCEP reanalysis fields, daily weather charts, and observational data for the region to categorize both surface and upper air patterns as specific types. This study is still in progress and so far most data have been analyzed for all but the summer months. This paper will report on the regional synoptic climate variations for all the months and correlate the conditions to assess greatest icing potential based on a 45-year period of record.