Five day running mean time longitude section of the 500-hPa height anomalies (45°N-60°N) calculated from daily anomalies. Anomalies are departures from the 1981-2010 base period daily means. (Text after NOAA, <a rel="nofollow" class="external text" href="http://www.cpc.ncep.noaa.gov/products/intraseasonal/500z_tlon_45-60n.shtml">500 hecto Pascals Height Anomalies 45oN-60oN</a>),
Illustrates early 2015 blockings; heat waves in India, Pakistan, U.S. West coast and Europe,
NOAA  / National Weather Service / National Centers for Environmental Prediction / Climate Prediction Center Internet Team
NOAA NCEP CPC &gt; Monitoring and Data &gt; Oceanic &amp; Atmospheric Data &gt; Monitoring Intraseasonal Oscillations <a rel="nofollow" class="external text" href="http://www.cpc.ncep.noaa.gov/products/intraseasonal/500z_tlon_45-60n.gif">500z_tlon_45-60n.gif</a>