Santa’s global weather briefing from Wilkens Weather and Rockwell Collins

Christmas Eve is upon us and as we say in Texas, Santa is fixin’ to get his sleigh packed. But first, he is checking with Wilkens Weather, A Rockwell Collins Company, for the first leg of his journey around the world.  From the North Pole, his first stops will likely be in Uelen, Chukotka in far eastern Russia.  

From what Santa has entered into Rockwell Collins ARINCDirect Flight Manager, he will leave the North Pole on Friday, December 24, 1155UTC (11:55 PM in far eastern Russia).  

A low pressure center just east of Svalbard has a strong front extending just across the North Pole and across most of the Laptev Sea.  As Santa stays behind the front, he will encounter some light snow showers but will be able to take advantage of a strong northerly tailwind.  Once he is south of 78°N, winds are forecast to turn westerly, which will be ideal for his final approach into Uelen.

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Where are the Christmas Winds?

The climate of Trinidad is strongly influenced by the North Atlantic High, also referred to as the Bermuda High or Azores High, based on its seasonal positioning. During the fall season, the Atlantic High moves southward in response to the southward push of low pressure systems and their associated cold fronts over North America and the North Atlantic. The high’s southward position and lower sea surface temperatures, north of 10°N, result in strong easterly trade winds across the eastern Caribbean during winter. This increase in winds typically occurs around mid to late December, giving them the seasonal name: the Christmas Winds.    Read More »

South China Sea Monsoon Low

WWT Satellite Monsoon LowOver the past several days, an area of low pressure (Invest 91W) developed within the monsoon trough/ITCZ, generating bands of showers and thunderstorms across the southern South China Sea. As a result, fresh winds extended to the Borneo coast and Malay Peninsula over the weekend. Strong to near-gale force northerly winds also occurred along the northwest side of the low when it intensified this morning. Global models often underdo monsoon winds within these lows and these systems should always be monitored closely for tropical development. Read More »

Harmattan Dust in West Africa

As we approach the end of the calendar year, meteorologists, once again, encounter a significant weather phenomena that can sometimes be a challenge to forecast: The Harmattan Winds.

Harmattan winds are derived from a dry and dusty, northeasterly trade wind that originates in the Sahara. As the monsoon trough shifts south during the boreal winter, the trade winds will travel further south reaching the West Coast of Africa. This type of wind is strengthened by low pressure over the north coast of Guinea and high pressure over Northwest African Journal of Environmental Science and Technology Harmattan DustAfrica. The Harmattans can carry desert dust into the Atlantic and the Gulf of Guinea leading to hazardous operations on and offshore. Another element to the strength of the Harmattan is eastward movement of a low pressure system over Europe and its subsequent surface cold front that will move over the Mediterranean into North Africa. While the cold air will mix and warm over Africa, the wind will continue to surge south carrying with it the blinding dust covering everything in its path. Crop soil from the Sahel, the region between the Sahara desert and humid savannas, can also be mixed up in the winds further dropping visibility.Read More »

Major Hurricane Wilma, 11 years later

CIMSS NOAA Satellite Montage WilmaHurricane Wilma was the 21st named storm of the infamous 2005 Atlantic hurricane season. From her formation on October 15th to her demise on the 26th, Wilma would become one of the most memorable hurricanes in Atlantic basin history. As the 4th category 5 hurricane of the year, Wilma would become a monstrous bookend to an incredible, record-setting season.Read More »

Remembering 2005’s Major Hurricane Rita in the Gulf of Mexico

Hurricane Rita made landfall in extreme southwestern Louisiana on September 24th, 2005 with an intensity of 100 knots (Category 3). About 48 hours earlier, Rita was a Category 5 hurricane with a minimum pressure of 895mb, the fourth-lowest central pressure on record in the Atlantic basin. Although Rita’s history was overshadowed by Katrina, which made landfall just a few weeks earlier, the storm provided a unique challenge for both forecasters and public officials.

NASA Rita Terra satellite_20050918
NASA satellite image of Tropical Depression Eighteen over the Bahamas on Sept. 18, 2005

Rita originated as a weak tropical wave off the western coast of Africa on September 7th. The Saharan Air Layer, commonly known as Saharan Dust, and high levels of wind shear prevented the wave from producing thunderstorm activity as it moved across the tropical Atlantic. Conditions became more favorable for development later in the month as the wave reached the Bahamas. A tropical depression formed on September 17th and the system was designated as Tropical Storm Rita the following afternoon.

Rita continued to strengthen as it tracked across the Florida Straits, reaching Category 2 status by the time it reached the Gulf of Mexico on the 20th. Over the next 18 hours, the storm underwent rapid intensification over the Loop Current, becoming a Category 5 storm with an intensity of 145 knots. Rita continued to intensify and recorded an incredible 70mb drop in central pressure in a 24-hour period. At maximum intensity on September 22nd, Rita’s central pressure was estimated to be 895mb with winds near 155 knots (178 mph).

NASA Aqua satellite_20050923
NASA satellite image showing Hurricane Rita approaching the Gulf coast on Sept. 23, 2005

Thankfully for the residents of the Gulf Coast, Rita did not maintain its unprecedented strength as it pushed ashore. After moving past the Loop Current the system gradually weakened to a Category 3 before making landfall near Sabine Pass as a major hurricane. Hurricane force winds spread over 150 miles from the center while tropical storm force winds stretched as far north as the Louisiana/Arkansas border. Peak storm surge of nearly 17 feet occurred on the eastern side of Rita, causing severe flooding in several parishes in southwestern Louisiana. Heavy rainfall worsened this situation, with most of southwestern Louisiana receiving 7-10 inches, with some areas receiving over 15.

Rita continued to progress northeastward after being absorbed by a front across the central United States. That accelerated movement prevented a significant flood event in the Ohio River valley, with most rainfall totals being limited to around 2-3 inches as the remnant low raced toward the Great Lakes.

Although meteorological impacts to extreme southeastern Texas and southwestern Louisiana were unforgettable, only seven direct deaths occurred as a result of Rita in the United States. Most citizens in the southwestern Louisiana coastal areas evacuated before the worst impacts arrived, likely significantly reducing the death toll in that area.

The majority of the storm’s causalities occurred during the evacuation iWWT Hurricane Rita Wind Speed Analysisn Texas, where poor planning and heightened fears, resulting from Katrina, resulted in mass gridlock around Houston. Over 100 Texans perished due to accidents, fires, and health related issues during the evacuation. Much work has since been done to streamline the evacuation process from the Houston area, including the streamlining of the contraflow process on major highways exiting the city.