Scientists Dissect Rare Typhoon Near Equator...

[Derecho]

Just found this googling, AP article from April 2003 discussing 2001 Typhoon Vamei that formed 1.5 degrees from the Equator....

http://www.usatoday.com/weather/news/20 ... amei_x.htm

The technical paper on it:

http://www.weather.nps.navy.mil/cpchang ... /vamei.htm

The JTWC report:

http://www.npmoc.navy.mil/jtwc/atcr/200 ... age39.html


As Stacy Stewart notes in the AP article, the reason for the lack of Atlantic storms below 10N isn't lack of Coriolis, it's a lack of initiating low pressure that far south.

Other basins have storms fairly commonly to within 4 degrees of the Equator, though 1.5 degrees is pretty odd everywhere. Interestingly Stewart claims a Vamei-type storm is theoretically possible west of Colombia.

[isobar]

Thanks for posting info about this historical event. Impressive banding on satellite considering its location.

They estimated the probability of that happening again at once in 100 to 400 years.

[PTrackerLA]

I never knew that could happen, thanks for sharing Derecho.

[Aslkahuna]

ehy the ATL doesn't have many storms developing below 10N is that a developing system quickly runs out of space over the water below 10N. Also the ATL doesn't have the Near Equatorial Trough with good cyclonic horizontal shear across it for the intiation of spin in the absence of Planetary Vorticity. Remember-vertical shear is bad for storms-horizontal shear-particularly in low levels is good and that was a significant factor in the formation of Vamei as well as STY Kujira earlier this year which intially spun up at Latitude 3.3N. For another interesting low latitude storm,
look up STY Kate in 1970.

Steve

[Aslkahuna]

ehy the ATL doesn't have many storms developing below 10N is that a developing system quickly runs out of space over the water below 10N. Also the ATL doesn't have the Near Equatorial Trough with good cyclonic horizontal shear across it for the intiation of spin in the absence of Planetary Vorticity. Remember-vertical shear is bad for storms-horizontal shear-particularly in low levels is good and that was a significant factor in the formation of Vamei as well as STY Kujira earlier this year which intially spun up at Latitude 3.3N. For another interesting low latitude storm,
look up STY Kate in 1970.

Steve