The bad weather conditions might once again delay NASA's launch plans, as it is determined to fuel the space shuttle Endeavour ahead of a possible Monday morning countdown.

It is clear from the move to fill the shuttle's gigantic external fuel that the U. S. space administration hopes to profit from a gap in the weather, however, it was specified by a spokesman that a 60 percent chance of launch-friendly conditions meant mission controllers were only "cautiously optimistic" of getting Endeavour away.

High humidity, low temperatures of around 9 degrees Celsius, and also the chance of ice gathering on the external tank, were other weather-related concerns which NASA thinks would contribute towards grounding the mission for a second time.

On Sunday, a bank of low cloud moved over the Kennedy Space Center in Florida, which delayed the endeavor's launch, when there were hardly any minutes left on the clock for the launch to happen.

Once the shuttle has been safely launched, the Endeavour's crew of six astronauts will work on a 13-day mission to provide and install the final U. S. module section to the orbiting International Space Station (ISS).