Australia starts January with hostile brush fires northeast of Melbourne while flooding rains from a tropical system (Koji) pounce on Queensland. So far, JAN-26 has produced unusually hot weather across Interior Southeast Australia where the brushfire regime emerged.

The latest U.S. gas population weight HDD forecast identifies the mild week ahead shifting much colder Jan. 16-22 and moderating back to near normal late month. AI and CFS/ECM each indicate another cold week to start February followed by milder weather. Arctic air risk is not indicated (for the U.S.) during the period.

The AI Graph Cast ECM ENS is the least wet biased model. Today’s 15-day AI GC percent of normal rainfall outlook for South America reveals a drier than normal pattern across most of Brazil and Central Argentina while the 24-hour change suggests a sneaky wet regime in Northern Argentina.

The consensus of operational models U.S. gas population weigh HDD forecasts is a trend from the early January warmth back to near normal for the week ending January 22nd. The 06Z GFS was colder than the 30-year normal. Interestingly, the ECM is colder for the second half of January across the Northern U.S. while CFS maintains the southern 2/3 of U.S. warmth. Therefore, the ECM/GFS HDD projections are near to below the 10-year normal in the extended range. However, the machine learning models are all cold to very cold for late January into early February.