Broome has recorded its hottest ever December since records began.
The Bureau of Meteorology has confirmed the daily maximum temperatures averaged 36.3 degrees, breaking the previous record set in 1951.
Forecaster Patrick Ward says it was an uncomfortably warm period throughout the West Kimberley.
"Broome airport scored it's hottest ever December, about two-and-a-half degrees above average, and hottest day for the month for 43 degrees on the ninth," he said.
"In terms of rainfall, about half the normal amount for a December."
Meanwhile, the Bureau's monitoring a monsoonal trough that will increase rainfall and the chances of cyclone activity over the next fortnight.
Forecasters say increased falls are likely across the Top End but it is not yet clear if the system will move south over the continent or remain offshore.
© ABC 2013
16:05 EDT The CSIRO and Bureau of Meteorology say updated climate change predictions confirm what they've been saying for years.