Saturday, September 21, 2013

Typhoon Usagi Moves Towards Hong Kong

Typhoon Usagi is this year's (so far) strongest storm, having reached a maximum wind of 160 mph in the Pacific a couple of days ago. Those have since "weakened" to 140 mph as of early this morning as the storm passes between Luzon and Taiwan, working west towards a date with China late tomorrow (early Monday their time).

Usagi had a rather impressive intensification streak between Wednesday and Thursday, intensifying from a tropical storm to a 160 mph storm in about 36 hours. These type of rapid intensifications aren't entirely rare -- we've seen storms like Wilma in 2005 pull it off -- but it does take a perfect set of atmospheric ingredients to pull off such an accomplishment. Usagi was able to do that.

What it's also going to do is drench Taiwan with copious rainfall, likely on the order of one to two feet. The combination of east winds to the north of the storm center and Taiwan's terrain will yield copious rainfall over the hills of Taiwan, which means flooding and mudslides are likely to occur despite the storm's brunt passing to the south.  Flooding from tropical systems is obviously one of their calling cards -- just ask those near Acapulco who dealt with the flooding from Manuel in recent days.

Usagi's track should bring the center of the storm near Hong Kong in about 36 hours or so. Hong Kong is no stranger to tropical cyclones, having dealt with dozens of them brushing near or going directly over the metropolis over the years. Usagi should weaken some as it approaches Hong Kong, with forecasters suggesting maximum winds should decrease with the storm to near 100 mph as it makes final landfall.

On our side of the globe, the Gulf disturbance that had shown signs of possibly developing into something will not. Instead, the system will merge with the cold front that's moving through our world tonight and will produce heavy rainfall in the Southeast and then spawn a low pressure center off of the Southeast coast that will push east and not impact us. Beyond that, little in the way of tropical development is expected for the next few days.