Little Change to 94L; Hawaii Watching Guillermo; TC 2 Kills 27 in Myanmar/Bangladesh

By Jeff Masters
Published: 13:10 GMT le 30 juillet 2015

A strong tropical wave that pushed off the coast of Africa on Wednesday (Invest 94L) was located a few hundred miles southwest of the Cape Verde Islands on Thursday morning, and was headed west at 15 mph. 94L does have conditions that favor some slow development over the next few days. Satellite images show that 94L has a decent amount of spin, but only a modest area of heavy thunderstorms that have not increased in organization this morning. Wind shear off the coast of Africa is moderate, 10 - 20 knots, ocean temperatures are a warm 28°C, and the atmosphere is reasonably moist. The 8 am Thursday run of the SHIPS model predicted that wind shear would remain moderate over 94L for the next five days, but ocean temperatures beneath it would cool to 26°C by Sunday, at which time 94L will encounter an increasingly dry and stable airmass courtesy of the Saharan AIr Layer (SAL). The SAL is dominating most of the tropical Atlantic, from the coast of Africa into the Central Caribbean, making 94L's long-term survival questionable. If 94L does manage to make it to the Caribbean, the high wind shear that has dominated the region all summer will likely tear the storm apart. The Thursday morning ensemble runs of the GFS and European models--done by running the models at lower resolution and varying the initial atmospheric conditions slightly to generate an "ensemble" of twenty potential weather situations (fifty for the European model)--do have a number of their 20 - 50 runs that develop 94L into a tropical depression, but none of these solutions have the storm that develops making it as far west as the Lesser Antilles Islands. The operational high-resolution versions of our three top models for predicting genesis of tropical cyclones--the GFS, European, and UKMET models--have one model, the European model, that does show possible development of 94L into a tropical depression by Sunday. In their 8 am Thursday Atlantic Tropical Weather Outlook., NHC gave 94L 2-day and 5-day odds of development of 10% and 30%, respectively.

Figure 1. Latest satellite image of Invest 94L near the Cape Verde Islands.

Hawaii should watch Guillermo
In the Eastern Pacific, Tropical Storm Guillermo has formed, and is something Hawaii should watch. Both the GFS and European models show Guillermo (or its remnants) getting within 500 miles of the islands by Tuesday, though the storm should be weakening at that time due to dry, stable air and cooler ocean temperatures.

Figure 2. Tropical Cyclone Two in the Bay of Bengal as seen at 05 UTC July 30, 2015, from the MODIS instrument on NASA's Terra satellite. JTWC gave top winds of 40 mph to the system, which made landfall over Bangladesh. Image credit: NASA.

Bay of Bengal's Tropical Cyclone Two kills 27
Tropical Cyclone Two made landfall near Chittagong, Bangladesh, on Thursday morning, bringing heavy rains and deadly landslides to portions of Bangladesh and Myanmar. At least 27 people have been killed in Bangladesh and Myanmar from the storm, according to an article by TWC's Nick Wiltgen. The coastal city of Chittagong reported 879 millimeters (34.61 inches) of rain in just a four-day period July 24 through 27 from the storm.

This may be my last post for a week, as I plan on taking some vacation time and turning the blog over to Bob Henson. He will have the latest installment in our "what to expect from El Niño" series--on how El Niño might affect winter weather in the Eastern U.S.--late this morning.

Jeff Masters

Comments (26) Permalink | A A A
About The Author
Dr. Masters co-founded wunderground in 1995. He flew with the NOAA Hurricane Hunters from 1986-1990. Co-blogging with him: Bob Henson, @bhensonweather

Recent Articles

Invest 94L Off the Coast of Africa May Slowly Develop

The first African tropical wave worthy of being classified by NHC as an area of interest (an "Invest") has emerged from the coast of Africa, and lies a few hundred miles southeast of the Cape Verde Islands. Invest 94L has conditions that favor some slow development over the next few days. Satellite images show that 94L has a decent amount of spin and a small but growing area of heavy thunderstorms. Wind shear off the coast of Africa is moderate, 10 - 20 knots, ocean...

Read Article - Comments (552)

What to Expect from El Niño: North America

We’re now well into the ramp-up phase of what promises to be one of the top three El Niño events of the last 60-plus years. Sea-surface temperatures (SSTs) in the Niño3.4 region--an area straddling the eastern tropical Pacific--are the most widely accepted index for the oceanic evolution of El Niño. NOAA announced in its weekly ENSO update on Monday (see PDF) that Niño3.4 SSTs were running 1.6°C degrees above the seasonal average for the week ending Monday. W...

Read Article - Comments (417)

Quiet in the Atlantic; Two Disturbances for Hawaii to Watch

The tropics have fallen silent the past two days, with no named storms anywhere on the planet. It's not unusual to see a quiet period for tropical cyclones in July, which lies before the climatological peak months of August, September, and October in the Northern Hemisphere (a tropical cyclone is the generic term for all tropical depressions, tropical storms, and hurricanes/typhoons). The tropical cyclone-free period will likely be short lived, though, as Invest 90...

Read Article - Comments (417)

Record Ocean Temperatures Threaten Hawaii's Coral Reefs

Record warm sea surface temperatures in Hawaii's waters threaten to bring a second consecutive year of record coral bleaching to their precious coral reefs this summer. According to NOAA, ocean temperatures in the waters near and to the south of the Hawaiian Islands were 1 - 2°C (1.8 - 3.6°F) above average in June, which was the warmest these waters have been since record keeping began over a century ago. With the waters surrounding Hawaii expected to warm to thei...

Read Article - Comments (1095)

Previous Entries