 Flying through overcast skies, the aircraft returned two hours later, its pilot having seen nothing out of the ordinary.On the night of 30 January it started to rain; from 2 February onwards this rain, low cloud and foggy weather (known locally as the "crachin") would last through much of the battle and severely hamper Allied air and artillery support.In the early morning hours of 31 January 1968, a division-sized force of PAVN-VC soldiers launched a coordinated attack on the city of Huế.