Hurricane
Joaquin Prompts New Warnings in Bahamas; U.S. East Coast Landfall
Concerns Growing
Hurricane warnings have been expanded to include more of the Bahamas as Hurricane Joaquin churns toward the nation of islands east of Florida. Despite considerable uncertainty, the odds of a landfall on the U.S. East Coast appear to be increasing, and the official forecast track suggests that Joaquin could become the first landfalling hurricane on the U.S. mainland in 15 months.
An
Air Force Reserve Hurricane Hunter reconnaissance aircraft measured
sufficiently strong flight-level winds and low surface pressure to
prompt the National Hurricane Center to upgrade Joaquin Wednesday
morning. The Hurricane Hunters found a 55-mile-wide eye, but it was
open on its north side – meaning that robust thunderstorms had not
fully encircled the Joaquin's center of circulation.
Hurricane Joaquin Information
The
latest statistics as provided by NOAA's National Hurricane Center.
Hurricane
Joaquin continues to intensify slowly, as wind shear – harmful to
the intensification of tropical cyclones – lessens, and a
complicated atmospheric pattern makes its future track – including
any potential landfall on the U.S. East Coast – extremely difficult
to forecast.
Residents
along the East Coast of the U.S. should pay close attention to the
forecast now through this weekend. It's a particularly difficult
forecast that hinges on the behavior of several different atmospheric
features over North America and the North Atlantic Ocean.
Aware
Threat Index
A
graphic highlighting areas that need to pay close attention to
forecasts as significant impacts could possibly be felt beneath the
orange shaded area within the next few days.
Computer
forecast models – and the meteorologists who rely on them for
guidance – are grappling with a complex interaction between
Joaquin, a cold front near the East Coast, the remnants of Tropical
Storm Ida, a strong bubble of high pressure aloft over the North
Atlantic Ocean, and a potentially strong area of low pressure aloft
digging into the southeastern U.S. later this week.
Ensemble
Forecast Mode Tracks
The
lines on this graphic represent several of the many ensemble track
forecasts from various computer models. This is not an official
forecast, but models such as these are often used as guidance for
creating the projected path for a storm.
Joaquin's
future depends critically on the position and relative strength of
those players – not to mention its own strength. Strong wind shear
had kept most of Joaquin's thunderstorm activity (convection) south
or east of its center of circulation, but that changed Tuesday
afternoon and evening as thunderstorms developed closer to its
circulation center.
Visible
Satellite
During
daylight hours, you will see the clouds more or less as they would
look to the naked eye from space. At night, it's too dark to see the
clouds, so this image will display infrared satellite data instead.
Because
Joaquin is strengthening and drifting ever closer to the Bahamas, the
government of that country has issued warnings and watches for much
of its territory. Here are the details as of 5 p.m. EDT:
- A hurricane warning is now in effect for the northwestern Bahamas including the Abacos, Berry Islands, Eleuthera, Grand Bahama Island, and New Providence, but excluding Andros Island and Bimini.
- A hurricane warning remain in effect for the central Bahamas, including Cat Island, the Exumas, Long Island, Rum Cay and San Salvador.
- A hurricane watch is now in effect for Bimini.
- A tropical storm warning is now in effect for the southeastern Bahamas including the Acklins, Crooked Island, Long Cay, the Inaguas, Mayaguana, and the Ragged Islands, but excluding the Turks and Caicos Islands.
Hurricane
Joaquin: Watches and Warnings
This
map shows watches and warnings issued by the Government of the
Bahamas. The latest position of the hurricane is also shown, along
with the forecast path over the next 24 hours (dark red) and 48 hours
(dark orange).
Hurricane
preparations should be rushed to completion in the hurricane warning
area.
Joaquin
is expected to slowly churn toward the Bahamas through Thursday. The
extent of the effects on those islands will depend heavily on how
close it gets and how much time it spends nearby before making the
anticipated northward turn.
At
this time, we expect some of the worst impacts in the Bahamas to
occur on San Salvador and Rum Cay, the islands closest to Joaquin's
current position. On San Salvador, rainfall totals could exceed 2
feet. Sustained tropical-storm force winds of 39 mph or greater may
develop Wednesday night and continue unabated for 48 hours or more.
Track Forecast: Still Extremely Challenging
Although
computer model simulations have had the advantage of ingesting
high-resolution real-world data from the Air Force reconnaissance
flight earlier in the day, it doesn't seem to have brought them any
closer to a consensus.
The
American GFS model forecast continues to show Joaquin making an
alarming northwestward turn, slamming it right into Virginia,
Maryland or North Carolina this weekend. Meanwhile, the European
ECMWF model suggests Joaquin has a chance of staying away from the
U.S. East Coast.
It
is simply too soon and the uncertainty is too high to determine any
impacts from Joaquin itself for the U.S. East Coast at this time.
The
National Hurricane Center's official forecast cone is below. The
official forecast remains a compromise between the competing
scenarios from the computer models.
Projected Ptah
Note
that the official intensity forecast now brings Joaquin to Category
3 strength
on Saturday morning, which by definition would make it a major
hurricane.
Regardless
of the ultimate outcome of Joaquin's path, portions of the East Coast
will still see multiple impacts from the evolving large-scale weather
pattern, including flooding rainfall, gusty winds, high surf, beach
erosion and some coastal flooding. Click the link below for more
information on that story.
Late
Week and Weekend Setup
Some
of the atmospheric forces at play over eastern North America and the
western Atlantic Ocean Friday through this weekend.
In
summary, here's what we know about Joaquin as of Wednesday's 5 p.m.
EDT advisory:
- Hurricane Joaquin's center is located about 175 miles east-northeast of the central Bahamas.
- Maximum sustained winds are estimated at 85 mph, a Category 1 hurricane on the Saffir-Simpson hurricane wind scale.
- As wind shear over the storm lessens, Joaquin should strengthen further the next 2 to 3 days.
- This system is moving slowly to the southwest and this is expected to continue through Thursday before turning north Friday into Saturday.
- Hurricane watches and warnings are in effect for parts of the Bahamas.
- Joaquin may directly or indirectly affect the East Coast late this weekend or early next week, and a landfall is possible.
- Moisture and/or energy associated with Joaquin could enhance rainfall along the cold front in the Northeast late this week. Regardless, the East Coast will see significant impacts from the larger scale weather pattern taking shape.
Flooding
and landslides triggered by Joining forces
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