This report presents a geostatistical method for analyzing wet/dry runway surface conditions using observational precipitation data for the United States (U.S.). Using the most recent U.S. Fourth National Climate Assessment as a primary resource, observed precipitation changes related to wet/dry days in the U.S. and their regional trends were identified.

Two sources of daily U.S. observed precipitation data were used: (1) the National Weather Service (NWS) Cooperative Observer Program (COOP) and (2) the Global Historical Climate Network (GHCN). Then, the regression kriging method was applied to estimate wet/dry days for ~ 3,300 National Plan of Integrated Airport Systems (NPIAS) airport locations.

Results show a general increase in dry days, which are particularly pronounced during a fall season, and an increase in wet days with absolute rainfall (R) > 10 mm. Regions particularly sensitive to change in wet/dry days are the western U.S. and the southeast. These regions are exposed to subtropical or tropical storm tracks coming from the Pacific and Atlantic Oceans.

DOT/FAA/TC-21/41 Authors: Jasenka Rakas and Jelena Lukovic