Yucatan Stan

Tropical Storm Stan
Tropical Storm Stan is holding together as it moves slowly across the Yucatan Peninsula. Stan came ashore this morning as a 45-mph tropical storm just south of Cozumel Island, the same place Hurricane Emily hit earlier this season. Stan looks pretty good for a storm whose circulation is over land--some impressive spiral bands lie to the east over the Caribbean, and the upper level ouflow is good on all sides except the west. The wind shear is a low 5 knots over the storm.

Stan will have to re-organize once it pops out into the Gulf of Mexico Monday, and will have at least 36 hours or so to intensify over the warm 29 - 30C waters of the Gulf as it tracks westward towards the northeast coast of Mexico. Wind shear is expected to remain very low, under 5 knots, and Stan could be a Category 1 hurricane as it approaches the Mexican coast south of Brownsville on Tuesday. It is not certain Stan will make it ashore on Tuesday, as the ridge that is driving Stan westward is forecast to weaken. Stan may stall, loop back, or even turn northwards and threaten the U.S. later in the week. Complicating the long range forecast is the fact that most of the computer models expect a second tropical storm to form in the region by Wednesday or Thursday. The formation location varies depending upon which model one looks at, but ranges from Key West to Cedar Key to west of Jamaica to the southern Bahama Islands, or possibly the Carolina coast.

Tropical Storm Otis
Hurricane Otis is now Tropical Storm Otis, with 70 mph winds. Otis is looking like much less of a threat to Mexico and Arizona today. This is a small storm, and is expected to weaken further before it crosses the Baja Peninsula Monday, bringing at most 3 - 6 inches of rain to that region. By the time Otis makes it to northern Mexico, the storm will have dissipated, and should bring only 2 -4 inches of mostly beneficial rains to drought-starved southern Arizona.

TD 19
Tropical Depression 19 is struggling with wind shear, and is not expected to live long. It is unlikely that this storm will get a name, and instead be torn apart by wind shear within three days as it heads northward over open ocean, far from land.

Elsewhere in the tropics
The disturbed area of weather that was 500 miles east of Trinidad and the southern Lesser Antilles Islands has diminshed, and tropical storm developement in this area is not expected. An area of clouds north of Puerto RIco is primarily due to a upper-level low, and development is not expected.

Taiwan and China
Typhoon Langwang (Chinese for Dragon King), made landfall on Taiwan at dawn Sunday as a Category 3 typhoon with 120 mph winds. Passage over the 10000 foot high mountains of Taiwan significantly weakened Longwang, which is expected to strike mainland China today as a Category 1 hurricane. Longwang did heavy damage on Taiwan, injuring at least 36 people. In a freakish double-whammy, a magnitude 5.4 earthquake hit the island as Longwang came ashore. No damage reports from the earthquake have been received yet.

My next update will be at 10pm EDT tonight.
Jeff Masters