Folks...I might be wrong here (it won't be the first time), but I
believe there's a chance that Hurricane Pali (in the Central Pacific)
could cross the equator (yes, it is theoretically possible!!). The
operative word, of course, is "chance." There is lots of uncertainty
when a rare tropical cyclone like Pali flirts with the equator because,
to my knowledge, it has never happened before.
Why do I believe there is a chance? Well, there are extremely anomalous conditions over the western and central Pacific Ocean right now. Specifically, a robust 500-mb high-pressure system to the west-northwest of Pali is actually strengthening (see GFS model analysis of 500-mb streamlines at 06Z today). I chose 500 mb because Pali's estimated central pressure is 982 mb, and the classic steering layer is the mean 400-850-mb wind, so I'm using 500 mb as a proxy).
The 06Z GFS model analysis of 500-mb streamlines and isotachs (meters per second) on January 12, 2016. Larger image. Courtesy of Penn State.
The anticyclonic circulation around this 500-mb high is anomalously strong at this latitude and time of year (long-term January mean of 500-mb vector winds), and it is driving Pali toward the equator. Ultimately, deep easterlies and the Beta effect will have a say in the future disposition of Pali's track relative to the equator.
I might be getting excited about nothing here, I freely admit, but I believe there's a chance, albeit it a slight one. Keep in mind that there's a lot of uncertainty here (Lee covers his you know what).
Best,
Lee
P.S. Many thanks to Chris Velden, Tim Olander, and Scott Bachmeier for their valued input.
Why do I believe there is a chance? Well, there are extremely anomalous conditions over the western and central Pacific Ocean right now. Specifically, a robust 500-mb high-pressure system to the west-northwest of Pali is actually strengthening (see GFS model analysis of 500-mb streamlines at 06Z today). I chose 500 mb because Pali's estimated central pressure is 982 mb, and the classic steering layer is the mean 400-850-mb wind, so I'm using 500 mb as a proxy).
The 06Z GFS model analysis of 500-mb streamlines and isotachs (meters per second) on January 12, 2016. Larger image. Courtesy of Penn State.
The anticyclonic circulation around this 500-mb high is anomalously strong at this latitude and time of year (long-term January mean of 500-mb vector winds), and it is driving Pali toward the equator. Ultimately, deep easterlies and the Beta effect will have a say in the future disposition of Pali's track relative to the equator.
I might be getting excited about nothing here, I freely admit, but I believe there's a chance, albeit it a slight one. Keep in mind that there's a lot of uncertainty here (Lee covers his you know what).
Best,
Lee
P.S. Many thanks to Chris Velden, Tim Olander, and Scott Bachmeier for their valued input.
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