  The fraction of observable nights is an essential parameter for selecting
astronomical sites. In recent years, meteorological satellite data have played
an essential role in recognising and providing statistics of observable nights.
We present a method to estimate the fraction of observable nights based on the
FengYun-2 series of geostationary meteorological satellites and weather records
of multiple astronomical sites. We have calculated the fraction of observable
nights at 27 sites in Indonesia and two astronomical sites in China to validate
the method. The results derived from our method show good agreement with
previous works. Furthermore, we have derived the yearly distribution of the
fraction of observable nights above China, which indicates the area near
40$^{\circ}$N has more observable nights than other areas in China.
