Negative SAM Inspires System Flip-Flopping

A warm NW'ly feed Thursday is followed by a cold polar blast through south-east Australia this weekend.

As prescibed in my last post the Southern Annualar Mode (SAM) undergoes a deep cycle shift into it’s negative mode over the next 7-10 days.

NOAA’s AAO (a.k.a. SAM) progs on of the deepest negative outlooks of the winter over the coming fortnight. Source: NOAA/GEFS

When the Southern Annular Mode (SAM) is negative, it leads to large wave patterns in the po…