National Climate Report - August 2013
Regional USCEI

« National Climate Report - August 2013

Regional USCEI

Summer Components

Summer RCEI

Regional Summer CEI Component Ranks
Region Rank
Warmest Maximum Temperatures
Northwest 4th biggest
Southwest 8th biggest
Coolest Maximum Temperatures
Southeast 4th biggest
Warmest Minimum Temperatures
Southwest 2nd biggest
West 3rd biggest
Northwest 4th biggest
Southeast 6th biggest
Northeast 10th biggest
Palmer Index Wetness
Southeast 2nd biggest
East North Central 2nd biggest
Palmer Index Drought
West 2nd biggest
Southwest 6th biggest
Extreme One-Day Precipitation
Northwest 2nd biggest
Northeast 5th biggest
East North Central 5th biggest
Central 6th biggest
South 8th biggest
Days With Precipitation
Southeast biggest

When these extremes are aggregated together, as in the Climate Extremes Index, several regions rank high for the CEI and for some of its components (see table above right). The days with precipitation component was the highest on record for the summer in the Southeast, and the persistent rain this season and earlier months cumulatively gave the region the second highest Palmer wetness index on record. In addition, the frequent cool fronts kept maximum temperatures low, while cloud cover kept minimum temperatures high, resulting in the fourth highest rank for cool maximum temperatures as well as the sixth highest rank for warm minimum temperatures. This combination of component extremes gave the Southeast an overall summer CEI which was the second largest in the 1910-2013 record for June-August. Persistent summer dryness and heat gave the West region the fourth largest summer CEI; persistent summer heat and extreme daily precipitation gave the Northwest region the seventh largest summer CEI; and persistent summer heat and long-term drought gave the Southwest the tenth largest summer CEI. When the various regional component extremes are aggregated together at the national level, the U.S. summer CEI ranked tenth highest due to the third highest extreme one-day precipitation component, fourth highest warm minimum temperature component, and high ranks for the long-term drought, long-term wetness, and warm maximum temperature components.

August Components

August RCEI

The extremes in temperature and precipitation gave certain regions unusually high ranks of the Climate Extremes Index (CEI), which is an index that combines extreme weather indices to show their cumulative impact. The second highest rank for Palmer Index wetness, third highest for cool maximum temperatures, and eighth highest for number of days with precipitation gave the Southeast region its seventh largest August CEI in the 104-year record (the Southeast had the third largest July CEI just last month). The Northwest region and West North Central region had the second biggest and fifth biggest rank, respectively, for the warm minimum temperature component. The West region and Southwest region had the second biggest and ninth biggest rank, respectively, for the Palmer drought component. The Central region and East North Central region had the sixth biggest and eighth biggest rank, respectively, for the days without precipitation component.