Wednesday, November 25, 2015

Sandra Becomes Latest Major Hurricane on Record

By , Senior Meteorologist
November 25,2015; 9:27PM,EST
 
 
Sandra remains on track to target northern Mexico Friday and Saturday, but it should be much weaker at landfall than its current major hurricane status.
Sandra became the latest major hurricane on record to form in the central/eastern Pacific or Atlantic oceans Wednesday afternoon. The equivalent of hurricanes that develop west of the International Date Line are called typhoons or cyclones.
An unnamed hurricane from 1934 in the Atlantic previously held the record when it was a major hurricane on Nov. 23 of that year. In the eastern Pacific Basin alone, the last latest major hurricane was Kenneth from Nov. 22, 2011.
There have now been nine major hurricanes in the eastern Pacific this year, a record for the basin.

Despite its current movement, a landfall in Mexico is expected on Saturday as a storm system located over the western half of the United States will pull Sandra to the north, then northeast later this week. Sandra, however, will not be a repeat of dangerous Hurricane Patricia.
Sandra will be well past its peak intensity as it approaches Mexico. Instead, strong wind shear will lead to weakening later this week.
Wind shear is the rapid change of direction and speed of air flow at different layers of the atmosphere. When wind shear is strong, these changes are very great and can shred apart tropical systems.
How fast Sandra weakens will determine its exact track into Mexico.
"The faster Sandra weakens, the quicker it will hook into mainland Mexico," stated AccuWeather Hurricane Expert Dan Kottlowski. In this scenario, Sandra would bypass Baja California to the south.
RELATED:
Mexico Weather Center
East Pacific Hurricane Center
Detailed Forecast for Cabo San Lucas

"If Sandra weakens slower, it could take a track right into Baja California Sur," Kottlowski continued.
Sandra will be a tropical storm as it reaches or makes its closest approach to southern Baja California Sur Friday night before moving into mainland Mexico, likely in southern Sinaloa state near or in between Culiacan and Mazatlan, on Saturday. It is even possible that Sandra makes its final landfall as a tropical depression.
Despite weakening, Sandra will still threaten parts of northern Mexico with flooding rainfall Friday into Saturday. Around the point of landfall, southern Sinaloa faces the greatest risk of widespread flooding and wind gusts of 65-95 km/h (40-60 mph).
"Rainfall amounts of 75-150 mm (3-6 inches) are possible in these areas with local amounts up to 250 mm (10 inches)," stated AccuWeather Meteorologist Eric Leister. "The biggest concern will be heavy rainfall that can cause flash flooding and mudslides."
Similar rain amounts are expected across southern Baja California Sur, including Cabo San Lucas. The extent and magnitude of tropical storm-force winds across the peninsula will be determined by the strength of Sandra and how close it tracks to land.

The threat for flooding will not be confined to places near Sandra's path. The storm pulling Sandra to the north will also draw its moisture and downpours much farther to the north across more of southern Baja California Sur and into Chihuahua later Thursday into Saturday.
"[In these areas,] there will be pockets of 25-50 mm (1-2 inches) with locally 100 mm (4 inches)," continued Leister. "The moisture is getting strung out, so that limits the torrential rain. Instead, there will be a 24-hour period of soaking rain with localized areas getting downpours that result in flooding."
Sandra's moisture will stream far enough to the north in the United States to contribute to an extensive period of ice in the southern High Plains and the risk for flooding elsewhere in the South Central states.
After reaching the Mexico coastline, the weakening tropical cyclone will dissipate over the higher terrain of northern Mexico later in the weekend.
 

No comments:

Post a Comment