Highest number of January Fremantle Doctor failure days in 45 years
The Fremantle Doctor has failed to arrive at Swanbourne by 3 PM on 12 days this January.
This is likely the highest number of January days with Fremantle Doctor failure on record since the observations at Swanbourne from 1985 and based on ERA-5 reanalysis, the highest number of days with Fremantle Doctor failure over Perth coastal regions by 3 PM since January 1976 when it failed for around 15 days!
The Fremantle Doctor in some years doesn't fail at all for a single day in January. In January 2000 and January 2012, it failed for 12 days.
All of January 1976, 2000, 2012 and 2021 had La Niña and a marine heatwave off the west coast of WA.
The Fremantle Doctor had also failed on 5 consecutive days twice this January, the last time it failed for more consecutive days was in January 2000 which had La Niña and for any summer month, February 2008 which also had La Niña.
La Niña strengthens the Leeuwin current which can induce marine heatwaves off the west coast of WA, making the Fremantle Doctor weaker and more likely to fail, in addition La Niña also leads to an increased tendency for positive Southern Annular Mode (SAM) conditions.
This is likely the highest number of January days with Fremantle Doctor failure on record since the observations at Swanbourne from 1985 and based on ERA-5 reanalysis, the highest number of days with Fremantle Doctor failure over Perth coastal regions by 3 PM since January 1976 when it failed for around 15 days!
The Fremantle Doctor in some years doesn't fail at all for a single day in January. In January 2000 and January 2012, it failed for 12 days.
All of January 1976, 2000, 2012 and 2021 had La Niña and a marine heatwave off the west coast of WA.
The Fremantle Doctor had also failed on 5 consecutive days twice this January, the last time it failed for more consecutive days was in January 2000 which had La Niña and for any summer month, February 2008 which also had La Niña.
La Niña strengthens the Leeuwin current which can induce marine heatwaves off the west coast of WA, making the Fremantle Doctor weaker and more likely to fail, in addition La Niña also leads to an increased tendency for positive Southern Annular Mode (SAM) conditions.