The Beijing Meteorological Observatory has been widely criticized for giving erroneous temperature forecasts from Sunday to Tuesday. The temperature it forecast for Tuesday was a full 6.2 degrees Celsius higher than the actual temperature and 5 degrees higher than on Sunday.

The false forecasts have triggered harsh words from Beijingers and some are doubtful if the meteorological departments will be able to produce a reliable forecasting service during the Olympics.

"Accurate weather forecasting will play a key role in hosting a successful Olympic Games and we started preparations in 2002 to improve our accuracy," said Ding Deping, director of Beijing Meteorological Observatory.

"However, Beijing's weather is very changeable in July and August and it poses a big challenge for Chinese meteorologists to forecast correctly during the Olympics," said Ding.

The Beijing Olympics will run from August 8 to 24 - the city sees about 40 to 50 percent of its annual precipitation during the same month.

The timing of the apology is nothing short of embarrassing for Beijing meteorological officials. On Wednesday, chief weatherman Sun Jisong of the Beijing Meteorological Bureau said, "Normally, weather services only tell people the possibility of rainfall, rough estimates of wind scale and temperature. During the Olympics, we will forecast the exact time of rainfall and be accurate to within minutes," Sun said.

It is not clear how far in advance weather forecasters will be able to issue forecasts for specific Olympic venues.

Deputy chief engineer Wang Yubin, with the Beijing Meteorological Bureau, said, "Issuing weather forecasts over the Olympics will be very labor intensive and will require considerable expertise by local forecasters. But a shortage of skilled weathermen will be a major hindrance."

Hundreds of experienced weathermen will be loaned out to the Beijing Meteorological Bureau to cope with the 17-day event, the Beijing Daily has reported.