National Park Service

Climate Monitoring in the Northern Colorado Plateau Network: Annual Report 2009 National Park Service

This report documents the 2009 monthly and annual climate summaries and climatic extremes for weather stations located within park units of the Northern Colorado Plateau Inventory and Monitoring Network (NCPN) and three stations located near park boundaries. In 2009, mean annual maximum temperature tended to be below average throughout much of the NCPN region, while precipitation was notably below long-term averages. Diff erences between long-term means and this year?s measures of average minimum and maximum temperature and total precipitation (and snowfall) were not related to the elevation gradient of stations. A general increase over the past 25?50 years in the 4-year composite, moving mean for mean annual minimum temperature is evident for most of the National Weather Ser-vice Cooperative Observer (Coop) stations in the NCPN. Conversely, there is evidence for a declining trend in snowfall over the past 20?25 years. Historical records for NCPN Coop stations indicate that an-nual precipitation has been highly variable, and that a strong unidirectional trend over the observation periods (15?82 years) is not readily evident.