Free | Publicly available
The Integrated Surface Database (ISD) consists
of global hourly and synoptic observations
compiled from numerous sources into a gzipped
fixed width format. ISD was developed as a joint
activity within Asheville's Federal Climate
Complex. The database includes over 35,000 stations
worldwide, with some having data as far back
as 1901, though the data show a substantial
increase in volume in the 1940s and again in
the early 1970s. Currently, there are over
14,000 "active" stations updated daily in the
database. The total uncompressed data volume is
around 600 gigabytes; however, it continues to
grow as more data are added. ISD includes
numerous parameters such as wind speed and
direction, wind gust, temperature, dew point,
cloud data, sea level pressure, altimeter setting,
station pressure, present weather, visibility,
precipitation amounts for various time periods,
snow depth, and various other elements as observed
by each station.