Joaquin became a hurricane this morning and is slowly strengthening.
Very complicated, very low confidence forecast.
Some comparisons have been made to Sandy. That's not really accurate. Sandy was a large quasi-tropical system during much of its approach to the United States. Joaquin is a hurricane, fully tropical, and will remain that through Sunday evening-Monday morning (when it'll either be onshore or shooting off toward Bermuda and Atlantic Canada). This means its windfield is considerably smaller. It may be considerably more intense than Sandy.
BASICS
...JOAQUIN BECOMES A CATEGORY 3 HURRICANE AS IT MOVES TOWARD
THE CENTRAL BAHAMAS...
SUMMARY OF 1100 PM EDT...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...23.8N 73.1W
ABOUT 90 MI...145 KM E OF SAN SALVADOR
ABOUT 170 MI...275 KM E OF THE CENTRAL BAHAMAS
MAXIMUM SUSTAINED WINDS...115 MPH...185 KM/H
PRESENT MOVEMENT...SW OR 220 DEGREES AT 6 MPH...9 KM/H
MINIMUM CENTRAL PRESSURE...951 MB...28.09 INCHES
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:
The government of the Bahamas has issued a Tropical Storm Warning
and a Hurricane Watch for Andros Island.
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
A Hurricane Warning is in effect for...
* Central Bahamas including Cat Island, the Exumas, Long Island,
Rum Cay, and San Salvador
* Northwestern Bahamas including the Abacos, Berry Islands,
Eleuthera, Grand Bahama Island, and New Providence
A Hurricane Watch is in effect for...
* Bimini
* Andros Island
A Tropical Storm Warning is in effect for...
* Southeastern Bahamas including the Acklins, Crooked Island,
Long Cay, the Inaguas, Mayaguana, and the Ragged Islands, but
excluding the Turks and Caicos Islands.
* Andros Island
A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area. Preparations to protect life and
property should have already been completed in the Central Bahamas.
A Hurricane Watch means that hurricane conditions are possible
within the watch area.
A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area.
For storm information specific to your area, please monitor
products issued by your national meteorological service.
DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 1100 PM EDT (0300 UTC), the center of Hurricane Joaquin was
located near latitude 23.8 North, longitude 73.1 West. Joaquin is
moving toward the southwest near 6 mph (9 km/h) and this general
motion is expected to continue over the next 24 hours. A turn
toward the northwest and north is forecast Thursday night or Friday.
The center of Joaquin is expected to move near or over portions of
the central Bahamas overnight and Thursday, and be near or over
portions of the Northwestern Bahamas Thursday night or Friday.
Data from an Air Force Reserve Hurricane Hunter Aircraft indicate
that maximum sustained winds have increased to near 115 mph (185
km/h) with higher gusts. Joaquin is a category 3 hurricane on the
Saffir-Simpson Hurricane Wind Scale. Additional strengthening is
forecast during the next day or so. Some fluctuations in intensity
are possible Thursday night and Friday.
Hurricane-force winds extend outward up to 35 miles (55 km) from the
center and tropical-storm-force winds extend outward up to 140 miles
(220 km).
The latest minimum central pressure estimated from reconnaissance
data is 951 mb (28.09 inches).
HAZARDS AFFECTING LAND
----------------------
WIND: Hurricane conditions are expected to reach portions of the
Central Bahamas by early Thursday morning. Winds are expected to
first reach tropical storm strength in the warning area tonight,
making outside preparations difficult or dangerous. Preparations to
protect life and property should be rushed to completion. Tropical
storm conditions are expected in the southeastern Bahamas beginning
tonight. Hurricane conditions are expected over portions of the
Northwestern Bahamas Thursday night or Friday.
STORM SURGE: A dangerous storm surge will raise water levels by as
much as 5 to 8 feet above normal tide levels in the Central Bahamas
in areas of onshore flow. A storm surge of 2 to 4 feet above normal
tide levels is expected in the Northwest Bahamas within the
Hurricane Warning area, and 1 to 2 feet is expected in the Southeast
Bahamas. Near the coast, the surge will be accompanied by large and
dangerous waves.
RAINFALL: Joaquin is expected to produce total rain accumulations of
10 to 15 inches over the central Bahamas and 5 to 10 inches over the
northwestern Bahamas and southeastern Bahamas. Isolated maximum
amounts of 20 inches are possible in the central Bahamas. This
rainfall could result in life-threatening flash floods.
SURF: Swells generated by Joaquin will affect portions of the
Bahamas during the next few days, and will begin to affect portions
of the southeastern coast of the United States by Thursday. These
swells are likely to cause life-threatening surf and rip current
conditions. Please consult products from your local weather office.
NEXT ADVISORY
-------------
Next intermediate advisory at 200 AM EDT.
Next complete advisory at 500 AM EDT.
Still no surprises. Joaquin is hitting its forecast points almost to a tee.
The discussion:
HURRICANE JOAQUIN DISCUSSION NUMBER 13
NWS NATIONAL HURRICANE CENTER MIAMI FL AL112015
1100 PM EDT WED SEP 30 2015
Joaquin has rapidly intensified during the past 24 hours with the
satellite presentation continuing to improve this evening. The eye
has recently become apparent near the center of the very symmetric
central dense overcast. An Air Force Reserve Hurricane Hunter
aircraft that has been investigating the hurricane this evening has
measured peak 700 mb flight-level winds of 113 kt and 102 kt surface
winds from the SFMR. These data support an initial intensity of
100 kt, making Joaquin the second major hurricane of the 2015
Atlantic hurricane season. NOTE: Communications problems have
delayed the public release of the Air Force reconnaissance data.
Joaquin continues to move slowly southwestward with an initial
motion estimate of 220/5 kt. The hurricane is forecast to move
slowly southwestward or west-southwestward for another 24 hours or
so while it remains to the south of a narrow northeast to southwest
oriented ridge. This ridge is expected to weaken by Friday as a
trough deepens and cuts off over the southeastern United States.
This should cause Joaquin to turn northward within 48 hours. The 18Z
runs of the GFS and HWRF remain in general agreement with the 12Z
UKMET and Canadian models moving Joaquin around the northeastern
portion of the cut-off low and bring the hurricane inland over the
Carolinas or mid-Atlantic states. The 12Z ECMWF remains the outlier
by showing a track toward the northeast out to sea. The NHC
forecast continues to follow the trend of the bulk of the guidance
and takes Joaquin toward the U.S east coast. The NHC track is
similar to the previous advisory and is once again east of the
multi-model consensus. The NOAA G-IV aircraft has recently
completed its synoptic surveillance flight, and data collected
during this mission should be assimilated into the 0000 UTC models,
hopefully reducing the spread of the track guidance.
The upper-level wind pattern over the hurricane is forecast by the
global models to become even more conducive during the next couple
of days. This favors additional intensification, with the only
possible limiting factors being upwelling of cool SSTs beneath the
slow-moving hurricane and eyewall cycles which could cause some
fluctuations in intensity. By 72 hours, increasing southwesterly
shear, dry air intrusion, and lower SSTs are expected to cause
gradual weakening. The updated NHC intensity forecast has been
significantly increased from the previous advisory primarily due to
the higher initial intensity. The official forecast is between the
lower statistical guidance and the higher HWRF during the first
36-48 hours, and is near the SHIPS/LGEM guidance after that time.
KEY MESSAGES:
1. Preparations to protect life and property within the warning
areas in the Central Bahamas should be completed now.
2. Confidence in the details of the forecast after 72 hours remains
low, since we have one normally excellent model that keeps Joaquin
far away from the United States east coast. The range of possible
outcomes is still large, and includes the possibility of a major
hurricane landfall in the Carolinas.
3. Every effort is being made to provide the forecast models with
as much data as possible. The NOAA G-IV jet has begun a series of
missions in the storm environment, and the National Weather Service
has begun launching extra balloon soundings.
4. Because landfall, if it occurs, is still more than three days
away, it's too early to talk about specific wind, rain, or surge
impacts from Joaquin in the United States. Regardless of Joaquin's
track, strong onshore winds will create minor to moderate coastal
flooding along the coasts of the mid-Atlantic and northeastern
states through the weekend.
5. A hurricane watch for a portion of the U.S. coast could be
required as early as Thursday evening.
6. Many portions of the eastern U.S. are currently experiencing
heavy rains and gusty winds associated with a frontal system. These
heavy rains are likely to continue for the next few days, even if
the center of Joaquin stays offshore. The resulting inland flood
potential could complicate preparations for Joaquin should it head
toward the coast, and even more substantial inland flooding is
possible if Joaquin later passes near or over these same areas.
FORECAST POSITIONS AND MAX WINDS
INIT 01/0300Z 23.8N 73.1W 100 KT 115 MPH
12H 01/1200Z 23.5N 73.8W 110 KT 125 MPH
24H 02/0000Z 23.6N 74.5W 120 KT 140 MPH
36H 02/1200Z 24.7N 74.8W 120 KT 140 MPH
48H 03/0000Z 26.6N 74.7W 110 KT 125 MPH
72H 04/0000Z 31.6N 74.7W 95 KT 110 MPH
96H 05/0000Z 36.2N 75.6W 85 KT 100 MPH
120H 06/0000Z 38.5N 76.5W 55 KT 65 MPH
Joaquin arrives during a time that was going to be very rainy anyway. It may exacerbate an already bad situation across North Carolina and Virginia, which have experienced flooding rains over the last few days.
"ALL MODELS ARE WRONG BUT THEY ARE ALWAYS USEFUL"
The "Cone of Uncertainty" is very wide for the Sunday-Monday period. This is the 5pm cone.
The "Cone" is developed using a suite of many computer models which run four times a day (0z, 6z, 12z, 18z, z being "zulu time".)
Most of the major model suites forecast a US landfall on Sunday, somewhere between the North Carolina-South Carolina border to New Jersey as a hurricane. One thing that's improved over the last 25 years is if a bunch of models have a consensus that's generally where the storm will go, within the bounds of that consensus. Track errors decrease every year. This is a good thing, because hurricane watches and warnings cost time and money and people (and this is universal the world over---seems to be engrained human behavior) tend to tune you out if you warn them and nothing happens, time and time again.
One model suite insists though that Joaquin will go out to sea. This model is the Euro.
It nailed Sandy several days out. It is generally one of the best. It has persisted while the others have persisted in taking this into the US coast. Joaquin will go out to sea. It keeps saying this.
Let's go back to "All Models are Wrong but They Are Always Useful." Why does one bunch say one thing and another, normally very reliable one say something else? For that we have to get our eyes off of the model output and get them onto a weather map. I love models, I really do, but I am generally old fashioned and I will generally look at a bunch of weather maps after I play with a bunch of model output. I am very much not a fan of modelcasting.
With the bunch that forecasts Joaquin to strike the US somewhere from the Carolinas to maybe Delaware Bay-Jersey Shore, they are dependent on several things. Let's look at a water vapour map from the last hour (as of the time of this writing).
Lots going on in here but the orange loop is the digging trough. The blue line is the stuck cold front currently soaking the East Coast. Joaquin is circled at the bottom right. There's a blocking high over the ocean. I probably have the other high in the wrong place.
That orange loopy thing will orient, or tilt, southeast to northwest. As we learned last night, that's called "negative tilt." Essentially the trough will cut off and get stuck over the southeast. Where this sets up will determine when and where Joaquin, if it does, makes that sharp hook into the US Coast, an uncommon--although not entirely unusual---track for a hurricane. See below for a very admittedly crude drawing superimposed over the water vapour imagery.
That's basically what a significant number of models have said will happen for the last several days, since the storm formed. It's also what happened with Hurricane Sandy. A different although similar flow drove Hurricane Isabel into the North Carolina coast and then up Chesapeake Bay in 2003 although Joaquin's possible path looks a lot like Isabel's.
But why is the Euro being difficult? Why can't it just go with the consensus? Let's look at another weather map!
That circled mess of clouds east of Joaquin are the absorbed remnants of Tropical Storm Ida. I am not sure whether it will become Ida again if it spins back up or if it'll get named Kate, but it apparently may do just that. As it moves north at a very slow rate, it may open a weakness in the blocking high south of Newfoundland and allow Joaquin to escape to the east.
Courtesy of The Vane
Dennis, at
the Vane, explains:
The above image is from this morning’s run of the GFS model showing us what it thinks the mid-levels of the atmosphere will look like around 2:00 AM EDT on Friday morning. Blue indicates lower heights (essentially, lower pressure), while oranges and reds indicate higher heights (higher pressure).
You can see Joaquin hanging out down near the Bahamas while the upper-level trough/low approaches from the west, and a ridge of high pressure and the remnants of Tropical Storm Ida sit over the ocean to the east. The GFS is one of the models that sends Joaquin careening into the East Coast—in this scenario, the trough lifts Joaquin to the north, and it gets caught against the high, and with nowhere else to go, it turns west and slams into the Mid-Atlantic.
This interaction between the trough, the hurricane, and the ridge/ex-Ida will determine what happens. It’s worth noting that some models—namely the European model—shows the trough kicking Joaquin out to sea like a kickball. The Euro has a stellar track record, especially when it comes to hurricanes, so a big reason for the uncertainty is that the Euro is showing such a dramatically different solution than many of the other big models.
And we see ex-Ida/Future-Kate maybe organizing itself back up. The Euro either is not handling that well or it's going to happen. If the Euro is wrong then that's a pretty big black eye for a usually competent and reliable model that has its own fan club amongst weather weenies. If it's right, then the others, including all of the American ones, need to have a looksee.
All Models Are Wrong but they are Always Useful indeed.
WHAT DO I THINK?
I think it is somewhat likely Joaquin will strike the US and the Euro's solution, right now, is somewhat unlikely. I am hesitant to assign a numerical probability because I'm waiting for this evening's model runs, and then I'm going to go look at a weather map again. This afternoon every forecast office east of the Mississippi released weather balloons. These balloons measure a great many things in the atmosphere from the surface all the way up to the stratosphere. They can tell us a lot. Those data are input into the models, along with the data from NOAA's Gulfstream jet, and that will be very key. It will be interesting to see if the Euro continues to kick the storm out to sea.
I'm also hesitant to assign a landfall location. It all depends on where and when the trough does its tilt and cuts off, and if Ida-Kate spins up. The further west the trough sets up, the further south Joaquin will turn into the coast. Ida-Kate might just pull Joaquin out to sea with it. Lots happening, lots of uncertainty. Beyond tomorrow this forecast is very low confidence.
It's always important to keep watch and prepare. And that's your BlackUWeather forecast.
Update tomorrow if I have the time.
(The quotes about models are my own variation on George Box's infamous "Essentially, all models are wrong, but some are useful" quote. I apologize for not making that clear up front.)
UPDATE: at 8pm Joaquin was upgraded to a Category 2 thanks to a Hurricane Hunter flight that found 105mph surface winds within the storm. Recon is still in the storm. It would not surprise me to see this intensify to a Category 3 at 11pm.
UPDATE 2 Recon found winds of 100kts. For those who don't know the math, that's 115mph. Joaquin is the second major hurricane of 2015, and may get stronger yet. Skill in forecasting intensity remains elusive but this could be, on approach to the Carolinas (if that happens), an intense hurricane.
UPDATE 3 This will likely be very bad for the Bahamas. Construction there is very good; they have gone through worse hurricanes relatively unscathed, but Joaquin may sit in the Bahamas until Friday night.
UPDATE 4 Updated with 11pm advisory. One thing I've left unremarked, because I'm still not entirely sure this will actually make landfall, is the cone shows the storm will significantly slow Sunday into Monday if it comes ashore. It's very important that the biggest impacts will be due to inland freshwater flooding. Had Joaquin arrived last 3 weeks ago, this rainfall would have been welcome. Now? Not so much. This will be the last update this evening. I will have an update tomorrow evening, when we'll definitely know where the storm is going to go. I can't stress enough that we kind of don't right now and the best I can give are "somewhat likely" or "somewhat unlikely."