Global Analysis - Summer 1999
Note: The data presented in this report are preliminary. Ranks and anomalies may change as more complete data are received and processed. Effective September 2012, the GHCN-M version 3.2.0 dataset of monthly mean temperature replaced the GHCN-M version 3.1.0 monthly mean temperature dataset. Beginning with the August 2012 Global monthly State of the Climate Report, released on September 17, 2012, GHCN-M version 3.2.0 is used for NCDC climate monitoring activities, including calculation of global land surface temperature anomalies and trends. For more information about this newest version, please see the GHCN-M version 3.2.0 Technical Report.
*The GHCN-M version 3.1.0 Technical Report was revised on September 5, 2012 to accurately reflect the changes incorporated in that version. Previously that report incorrectly included discussion of changes to the Pairwise Homogeneity Algorithm (PHA). Changes to the PHA are included in version 3.2.0 and described in the version 3.2.0 Technical Report. Please see the Frequently Asked Questions to learn more about this update.
|The global mean temperature for June through August, 1999, was well above the long-term average, based on preliminary data. In fact, for nearly every month in the past 10 years, the global mean land temperature has been above the long-term (1880-1998) mean. Even so, this 3-month global mean temperature was considerably cooler than the record warmth experienced in June through August of 1998, largely due to cooler sea surface temperatures this year. See the Global Analysis and Global Regional Analysis pages for more details on the global climate.|
|Based on preliminary data, average total precipitation for the contiguous U.S. for the period June through August 1999 was well below the long-term average, falling below the long-term average for the first time in 8 years. The bars in this graph are departures from the 1895-1998 mean. The curved line is a nine-point binomial filter which shows the decadal-scale variations. See the U.S. National Analysis and U.S. Regional / Statewide Analyses pages for more details on the U.S. climate.|