Category 1 Typhoon Sanba hits Korea; 92L and 93L not a threat

Typhoon Sanba battered South Korea on Sunday as a Category 1 typhoon with 90 mph winds. Sanba brought sustained winds of 46 mph, gusting to 69 mph, to Busan, South Korea, and heavy rains of 8.82" (212 mm) fell in 12 hours at Jeju, an island just south of the South Korean coast. Sanba is being blamed for two deaths and widespread power outages in South Korea and Southern Japan. Sanba has weakened to a tropical storm, and is lashing the North Korea and neighboring regions of China and Russia with heavy rains today. There are concerns that Sanba's rains will aggravate the food situation in North Korea, where two-thirds of the country's 24 million people are dealing with chronic food shortages. In August, Typhoon Bolaven flooded 127,500 acres of farmland in North Korea, and killed 59 in the country. Sanba pounded Okinawa, Japan early Sunday morning local time as a Category 3 storm with 120 mph winds, flooding 370 homes, mostly on the northern end of the island. Oku, on the northern tip of the island, experienced a gust of 124 mph (55.3 m/s), and 7 inches of rain fell on the island. Sanba became a Category 5 Super Typhoon with 175 mph winds for an 18-hour period ending at 12 UTC Friday, September 14, making it Earth's only Category 5 tropical cyclone so far in 2012.


Figure 1. Huge waves pound Yeosu City, South Korea, on September 17, 2012, as Category 1 Typhoon Sanba makes landfall. AP photo.


Figure 2. Radar image of Typhoon Sanba at landfall in South Korea at 9:50 am local time Monday September 17, 2012. Image credit: Korean Meteorological Agency.

Invest 92L in the Lesser Antilles
A tropical wave (Invest 92L) bringing a few heavy rain showers to the Lesser Antilles Islands is moving west at 15 mph. The wave is under a moderate 10 knots of wind shear, and has only a small amount of heavy thunderstorm activity, due to a large area of dry air surrounding the system. The amount of heavy thunderstorm activity has increased some this morning, though. The latest SHIPS model forecast predicts shear will be light to moderate, 5 - 20 knots, through Wednesday, which will favor development. However, the atmosphere over the Caribbean is unusually dry and stable, and this will make it difficult for 92L to organize quickly. 92L will bring heavy rain showers to the Dominican Republic on Wednesday, Jamaica, Haiti, and eastern Cuba on Thursday, the Cayman Islands and Central Cuba on Friday, and Mexico's Yucatan Peninsula, Honduras, and Western Cuba on Saturday. None of the reliable models develop the system. In their 8 am EDT Tropical Weather Outlook, NHC gave the wave a 0% of developing into a tropical depression by Wednesday morning, but these odds will probably rise as 92L reaches the Central Caribbean on Wednesday.


Figure 3. Morning satellite image of Invest 92L.

Invest 93L in the Gulf of Mexico no threat
An area of low pressure in the Northern Gulf of Mexico off the Louisiana coast (Invest 93L) is bringing heavy rains to the coast, but is moving inland, and development into a tropical depression will not occur.

Nadine may be around another week
Long-lived Tropical Storm Nadine has already been around a week, and may stick around at least another week, as it heads east-northeastward on a track that will bring the storm close to the Azores Islands on Wednesday and Thursday. Steering currents for Nadine are expected to collapse by Wednesday, and the storm will move slowly and erratically for many days in the Central Atlantic late this week and early next week. On Friday, Nadine will become tangled up with an upper-level low pressure system, and the storm may partially or fully convert to an extratropical storm. By this weekend, Nadine is expected to drift southwestward, and could become fully tropical again.


Figure 4. Hurricane Nadine as seen by the MODIS instrument on NASA's Terra satellite at 9:45 am EDT Sunday September 16, 2012. At the time, Nadine was at peak strength--a Category 1 hurricane with 80 mph winds. Image credit: NASA.

Jeff Masters