Hurricane Irene Coordination Message #3

August 26, 2011 Rob Macedo Leave a comment

Hello to all..

..Dangerous Major Hurricane Irene is making its way toward the US East Coast and may intensify slightly as it approaches. Its current expected track will then be to impact the Carolina Coast tracking to a position over or just inside the Outer Banks of North Carolina with potential impact to New England in the late Saturday to Sunday timeframe..
..Multiple Models are in agreement on a potential impact to Southern New England in the late Saturday to early Monday timeframe. All of Southern New England is in the ‘cone of uncertainity track error’ for the extended period. The extent on specifics of impact are too early to state at this time but Heavy Rain, Gusty Winds, and Coastal Flooding and Beach Erosion along the South Coast of New England remain potential threats..
..The threat from Irene is far different from the threat Hurricane Earl posed in 2010. This is explained in detail in this coordination message..
..The westward shift in the models late last night through this morning has now been followed in an eastward shift in some of the models. One should not pay attention to these shifts especially where much of the region will be on the damaging wind/severe weather side of this large hurricane and further modifications in track can occur. This is explained in detail in this coordination message..
..The National Hurricane Center (NHC) advises that Interests along the US East Coast from the Mid-Atlantic northward to New England closely monitor the progress of Dangerous Major Hurricane Irene..
..VoIP Hurricane Net and Hurricane Watch Nets have stood down and will reactivate with WX4NHC, the Amateur Radio Station at the National Hurricane Center Saturday Morning lasting through the weekend..
..Interests in Southern New England should closely monitor the progress of Major Hurricane Irene. Further monitoring and preparations should be made to prepare for the potential of impact from Major Hurricane Irene..
..SKYWARN Activation with Ops at NWS Taunton are likely some time late Saturday Night or early Sunday Morning lasting through Monday for impact of Major Hurricane Irene..
..ARES/RACES/MARS/EMCOMM Groups should closely monitor the progress of Major Hurricane Irene and seek advise from local leadership on stand-by status for their area..

Dangerous Major Hurricane Irene has moved away from the Bahamas after causing significant damage on portions of the island chain. Irene is gradually turning northward, taking aim on the Outer Banks of North Carolina, followed by a track parallel to the coast towards New York City, Long Island and New England. The current NHC track brings the system up to the Outer Banks of North Carolina, along the coast of New Jersey, Western long Island and then on a track towards Southern New England as a hurricane. Models are in decent agreement, however, we are still about 3 days out and the details and exact track could change. There are track errors of up to 150-175 miles over this period that could still occur. The track error ‘cone of uncertainty’ is over all of Southern New England with the latest forecast package. It is difficult to get into any specific impacts but Heavy Rains, Gusty Winds, and Coastal Flooding to South Coastal New England are all potential threats. For New England hurricanes, Heaviest rain are along and to the west of the track with potential for pockets of damaging winds. On the east side of the track, rainfall will be less but a much greater threat for widespread damaging winds. In the latest NHC advisories, interests along the US East Coast from the Mid-Atlantic northward to New England should monitor the progress of Major Hurricane Irene.

The VoIP Hurricane Net and Hurricane Watch Net have been active over the past couple days for Irene’s impact the Turks and Caicos Islands and the Bahamas and have deactivated, along with WX4NHC, the Amateur Radio Station at the National Hurricane Center. See their respective net links and the link to WX4NHC for details:

VoIP Hurricane Net:
http://www.voipwx.net

Hurricane Watch Net:
http://www.hwn.org

WX4NHC – Amateur Radio Station at the National Hurricane Center:
http://www.wx4nhc.org

High Surf conditions will begin to affect the New England coast in a few days. Swells and Rip Currents can be very dangerous to both the experienced and inexperienced swimmer. A rip current risk statement was issued Thursday Evening by NWS Taunton. See links below:

NWS Taunton High Surf Advisory/Rip Current Risk Information:
http://kamala.cod.edu/ma/latest.whus41.KBOX.html

NWS Taunton Surf Zone Forecast Information:
http://forecast.weather.gov/product.php?site=NWS&format=CI&version=1&glossary=1&highlight=on&issuedby=BOX&product=SRF

There have been a number of questions from Non-Governmental Organizations and Emergency Management regarding the track of Irene and the track with Earl. There are some significant differences here and they are as follows:

1.) The overall model guidance track of Irene is west of the overall model guidance with Earl.
Last year, Hurricane Earl’s midpoint guidance was about 50-100 miles offshore of Nantucket with some wobbles as far west as the mid to Outer Cape and between Nantucket and Marthas Vinyeard. With Major Hurricane Irene, the west most guidance is the New York City area and Western Long Island New York with the eastern most guidance just east of the Outer Cape and Nantucket. The midpoint of the guidance is somewhere over Southern New England for Major Hurricane Irene. Models have been persistent with this track and that’s why this is different from Earl. There can still be 200 nautical mile track error and that will impact specific conditions but Irene’s impact will be larger than Earl’s was last year. As we get closer, the details will be better known.

2.) Irene is expected to be a stronger system than Earl
With Earl in 2010, he weakened fairly quickly from a strong Category 3 to a Category 1/Tropical Storm. With Irene, she is expected to be a much stronger system as she comes through the region. This will also impact conditions over the region along with the closer track.

3.) The trough at the mid-levels of the atmosphere will amplify much more than the interaction between the trough axis and Earl in 2010. This is another factor in why Irene’s track will be closer to the coast than Earl’s was in 2010 resulting in more significant impact by Irene this year than Earl in 2010.

There have been some questions on the further westward track in the computer models. These wobbles and changes are expected for another few model cycles. After trending west late Wednesday Night into Thursday Morning, some models have started the trend eastward once again. Irene is a large hurricane and there will be various significant impacts across the US East Coast from the Carolinas northward to New England. In the next 24 hours, further specifics and better run-to-run consistency on the track should take hold. Being on the eastern end of Irene means a greater risk for damaging winds, severe weather and coastal storm surge flooding in South Coastal Massachusetts. Only if Irene tracks farther inland would this reduce some of the threats of Irene below hurricane strength due to land interaction but with some of the eastward shift in some of the reliable model guidance, that still isn’t the most likely scenario and people should still prepare as if a hurricane could impact the region unless model guidance converges further west.

Amateur Radio and Non-Amateur Radio SKYWARN Spotters should continue to keep high situational awareness regarding the track and intensity of Hurricane Irene. People should continue reviewing and start acting on their preparedness measures for tropical storm/hurricane force conditions as a precaution. This information has been provided via the Hurricane Preparedness Week Public Information Statements of Safety Tips via the link below and via a hurricane preparedness guide with a link to that listed below as well:

http://beta.wx1box.org/local/hurrpre.txt
http://www.erh.noaa.gov/box/announcement/hurricanePreparedness.pdf

SKYWARN Activation with Ops at NWS Taunton are likely some time late Saturday Night or early Sunday Morning lasting through Monday for impact of Major Hurricane Irene. ARES/RACES/MARS/EMCOMM Groups should closely monitor the progress of Major Hurricane Irene and seek advice from local leadership on stand-by status for their area.

Once again, Hurricane Irene should be monitored closely by people in Southern New England. The latest NWS Taunton Hazardous Weather Outlook and advisory/track information on Major Hurricane Irene from the National Hurricane Center are listed below:

NWS Taunton Hazardous Weather Outlook:
http://kamala.cod.edu/ma/latest.flus41.KBOX.html

National Hurricane Center – Miami Florida Information:

Hurricane Irene Public Advisory Information:
http://kamala.cod.edu/TPC/latest.wtnt34.KNHC.html

Hurricane Irene Technical Discussion Information:
http://kamala.cod.edu/TPC/latest.wtnt44.KNHC.html

Hurricane Irene Forecast/Advisory Information:
http://kamala.cod.edu/TPC/latest.wtnt24.KNHC.html

Hurricane Irene Wind Speed Probabilities:
http://kamala.cod.edu/TPC/latest.font14.KNHC.html

Hurricane Irene Track Map provided by the National Hurricane Center:
http://www.nhc.noaa.gov/refresh/graphics_at4+shtml/025514.shtml?5-daynl#contents

The next coordination message will likely be posted either Friday Morning or Friday Evening pending further computer model data on the track of Irene and significant updates to Irene’s status as a tropical system from an intensity perspective as well as the status on Watches and Warnings for the region.

Respectfully Submitted,

Robert Macedo (KD1CY)
ARES SKYWARN Coordinator
Eastern Massachusetts ARES Section Emergency Coordinator
Home Phone #: (508) 994-1875 (After 6 PM)
Home/Data #: (508) 997-4503 (After 6 PM)
Work Phone #: 508-346-2929 (8 AM-5 PM)
Email Address: rmacedo@rcn.com
http://ares.ema.arrl.org
http://beta.wx1box.org