Potential tropical cyclones are having a tough go of it during these waning days of the 2016 Atlantic hurricane season. Forecasters have been watching Invest 99L
for most of this week east of the Bahamas. 99L’s showers and thunderstorms (convection) have never consolidated around a single closed center of low pressure. On Friday morning, 99L consisted of a small pocket of convection near its center and weak showers and storms ringing 99L’s very broad area of low pressure. The entire system will soon accelerate north and get pulled into a midlatitude storm expected to intensify over New England on Friday night and Saturday. In its 8 am EDT Friday
Tropical Weather Outlook, the National Hurricane Center gave 99L only a 40% chance of developing into a tropical or subtropical cyclone before it loses its identity, and that may be generous. Moisture feeding from 99L into the midlatitude cyclone and an associated front will produce heavy, drought-easing rains this weekend
from Pennsylvania to New England, with 3” - 5” expected from central New York across much of New Hampshire and Maine. Figure 1.
A broad loop of showers and thunderstorms is spiraling into 99L, shown here in a visible satellite image from 10:45 am EDT Friday, October 21, 2016.Another wave to watch in the tropical Atlantic
It’s very late in the season to look for any development in the central Atlantic, but a tropical wave centered around 11°N and 44°W on Friday morning bears watching. Strong wind shear is now pushing dry air into the wave, limiting the amount of convection present. The shear over the wave may lessen over the next couple of days, and sea-surface temperatures of around 28 - 29°C (82 - 84°F), about 0.5°C above average, are more than adequate to support development. All 20 of the GFS ensemble members from Thursday night (00Z Friday), and almost half of the 50 ECWMF ensemble members, develop this wave over the next 2 to 5 days into at least a tropical depression, with some support for tropical storm formation. A weak upper low east of the Lesser Antilles may interact with this wave, complicating any potential development. If the wave does develop, it would most likely move north or northwest and remain far from land, perhaps stalling in the open central Atlantic later next week.
The next name on the Atlantic list is Otto, and getting to that point would be noteworthy. Since regular naming of Atlantic tropical cyclones began in the early 1950s, we have had only 10 “O” storms, all of them developing during the active period of Atlantic hurricane activity that began in 1995:
Oscar, 2012Figure 2.
Forecasts for the total number of hurricanes in the 2016 Atlantic season, issued by the groups shown along the bottom legend. For groups that issue more than one outlook per season, the most recent outlook is shown here. The average forecast across groups was for 8 hurricanes, as compared to the 6 that have occurred through October 21. Image credit: Colorado State University/XL Catlin/Barcelona Supercomputing Center
.The Atlantic season to date
This year’s predictions of a near-average to slightly above-average 2016 Atlantic hurricane season are looking quite close to the mark as the season begins to wind down. As of October 21, the Atlantic has seen 14 named storms, 6 hurricanes, and 3 major hurricanes. This compares to the 1981-2010 average of 12.1 named storms, 6.4 hurricanes, and 2.7 major hurricanes.
The outlooks from most forecast groups (see Figure 2 above) leaned toward a higher number of hurricanes than we've actually seen. However, in terms of accumulated cyclone energy (ACE)--which integrates the lifespan and wind-speed intensity of each tropical cyclone--it’s been a more active year than one might expect from hurricane counts alone. This is mainly a result of the strength and duration of the year’s three major hurricanes: Gaston, Matthew, and Nicole. As of October 21, the 2016 Atlantic season had racked up an ACE total of 133
, which is 144% of the typical ACE for the year to date and 128% of the typical total ACE for a season. Figure 3.
A resident of a home destroyed at the height of Typhoon Haima in Cabagan town, Isabela province, north of Manila on October 21, 2016. Cabagan and nearby areas on the east side of coastal mountains took the hardest hit from Hamia’s Category 4 winds. Image credit: Ted Aljibe/AFP/Getty Images)Haima heads into China after departing the typhoon-weary Philippines
Residents of the Philippines’ northern Luzon Island are picking up the pieces and assessing damage after a powerful one-two blow from Typhoon Sarika
, which made landfall as a borderline Category 3/4 storm with 130-mph winds on Sunday morning, followed by Typhoon Haima
making landfall as a Category 4 storm with 140-mph winds on Wednesday night. Haima’s landfall point was only about 130 miles north-northeast of Sarika’s. At least two deaths and $80 million in damage were reported in the Philippines from Sarika. Haima is being blamed for at least 13 deaths in the Philippines, and widespread damage is expected to mount into the hundred of millions of dollars.
Haima made landfall between Hong Kong and Shantou, China, as a Category 1 storm late Friday night local time. With dry air now infiltrating the cyclone, additional heavy rains should be fairly limited as Haima moves inland and spins down below typhoon strength. The combined economic impact in China from Sarika and Haima is estimated at more than $800 million
, according to Aon Benfield’s Steve Bowen. More than 6000 homes and more than a million acres of cropland have been affected in China, largely from Sarika.
In the Philippines, Baguio City (population 350,000) picked up over 14” (361 millimeters) of rain from Haima on October 20, and Tuguegarao City recorded 9.65 inches (245 mm.) Wind reports are scant across the region, but photos on the ground and satellite imagery reveal widespread destruction to the landscape and the built environment. Josh Morgerman of @iCyclone
was located at Tuguegarao City, located in the Cagayan Valley about 25 miles inland. Though the city was shielded from Haima’s landfall by a coastal range of mountains, Morgerman documented widespread damage in the area (see embedded video below). Morgerman recorded a central pressure of 942 millibars at 1:24 am local time Thursday morning as Haima’s eye passed over. Thousands of people reportedly stayed in or near shelters
between the landfalls of Sarika and Haima, which may have played a big role in reducing deaths and injuries from Haima. Both typhoons made landfall in relatively unpopulated stretches of coastline; this greatly limited the odds of a catastrophe along the lines of Super Typhoon Haiyan, which killed thousands in the Philippines in 2013.
We’ll be back with a new post on Monday. Have a great weekend, everyone!
Bob Henson and Jeff MastersFigure 4.
MODIS satellite image of Typhoon Haima taken at 1:30 am EDT October 20, 2016. At the time, Haima was a Category 2 storm with 105 mph winds, and was located between the Philippines’ Luzon Island and the coast of China. Image credit: NASA.