Our First Supertyphoon of 2007?

Typhoon Yutu in the West Pacific, currently recurving and heading towards Iwo Jima. Image credit: Naval Research Laboratory.

Over the past day or so, the second Pacific typhoon of the year--Yutu, or Amang--has rapidly intensified. The Joint Typhoon Warning Center now puts the storm's strength at 125 knots (mid-range Category 4) based upon satellite imagery; while the folks at the University of Wisconsin-Madison, using the Advanced Dvorak Technique, have Yutu as our first Category 5 storm of the year. They estimate 137 knots as I write this.

Either way, Yutu is an extremely powerful typhoon (although nothing extraordinary for the West Pacific, which hosts the strongest stroms on earth). It will be interesting to see whether the Joint Typhoon Warning Center agrees with the Wisconsin folks and names Yutu a Cat 5 in the next advisory. The cutoff for Category 5 is 135 knots. Meanwhile, the cutoff for Supertyphoon status is 130....

UPDATE MAY 21: Apparently Yutu didn't make it to official Cat 5 or supertyphoon status; it began a weakening phase following this post and is now transitioning into extratropical cyclone status even as it prepares to slam Iwo Jima. We still await both our first Cat 5 hurricane and our first supertyphoon of 2007....

P.S.: I'm also pleased to announce that Norm Doering, who helped me out researching Storm World, is going to keep an eye on hurricanes for me this week while I'm away. Norm won't blog unless there's anything dramatic with the weather, but he'll be on call....