Tropical Storm Henri Coordination Message #4 – Henri Impacts Sunday 8/22/21-Monday 8/23/21

Hello to all…

..Tropical Storm Henri on track and poised to strengthen and affect Southern New England Sunday into Monday as either a Category-1 hurricane or a strong tropical storm with a landfall somewhere between Eastern Connecticut and Long Island NY or points west some time late Sunday. Preparations to protect life and property should be rushed to completion..
..A Hurricane Watch remains in effect from Watch Hill Rhode Island to Westport Massachusetts and includes Kent, Washington, Bristol and Newport Counties of Rhode Island. The Hurricane Watch east of Westport Massachusetts is cancelled..
..A Tropical Storm Warning remains in effect from Watch Hill Rhode Island to Woods Hole Massachusetts and includes Kent, Bristol and Washington Counties of Rhode Island, Southern Bristol, and Southern Plymouth Counties of Massachusetts. In addition, Tropical Storm Warnings have been expanded into Northern Connecticut. Cape Cod and the Islands while not under a Tropical Storm Warning should still monitor for the potential of strong winds in addition to storm surge..
..A Storm Surge Warning is in effect from Flushing New York to Chatham Massachusetts including Marthas Vineyard and Nantucket for the late Saturday Night to Monday timeframe with a Storm Surge Watch remaining in effect from Chatham to Sagamore Beach Massachusetts..
..A Flood Watch is now in effect for Northern Connecticut, Rhode Island, Franklin, Hampshire, Hampden and Worcester Counties of Massachusetts from Saturday Evening through Monday Morning for 3-6″ of rain with isolated higher amounts. This rainfall can cause flooding of urban and poor drainage areas, rivers and streams particularly given the prior rainfall of the past 6-8 weeks..
..The Storm Prediction Center (SPC) has placed much of Southern New England in a marginal risk for severe weather for Sunday for the potential of thunderstorms mixing damaging winds down to the surface as well as the risk for isolated tornadoes..
..Additional Watches and Warnings will be required for other parts of Southern New England in future updates..
..Remnants of Tropical Depression Fred caused significant heavy rainfall in portions of Connecticut, Western, Central and Northeast Massachusetts on Thursday along with severe weather with two confirmed tornadoes in Clinton, Massachusetts and Thompson, Connecticut..
..SKYWARN Self-Activation is likely the potential impacts of Henri for Sunday into Monday. ARES/RACES and other similar groups should closely monitor the progress of Henri and seek advice from their leadership. Pictures, videos and post storm damage reports from Thursday’s severe weather event and upcoming impacts from Henri can be sent as a reply to this email, via our WX1BOX Facebook and Twitter feeds and through the email address pics@nsradio.org..

For Thursday, the remnants of tropical depression Fred caused two confirmed tornadoes in Clinton, Massachusetts and Thompson, CT. A waterspout from the same parent cell that caused storm damage in Thompson, CT occurred in Webster, Massachusetts. Further details on these tornadoes can be seen in the Public Information Statement at the following link:

NWS Boston/Norton Public Information Statement – Thursday 8/19/21 Confirmed Tornadoes:
https://kamala.cod.edu/offs/KBOX/2108202338.nous41.html

Tropical Storm Henri should reach hurricane strength later Saturday. Henri has turned northward and will bend north-northeastward before resuming a northward and then northwest and/or west-northwest portion and head on a path that will bring it over a part of Long Island New York and then the Southern New England coast. There remains conflicting signals in the weather model guidance. Some models are potentially trying to pull Henri further into New York City and possibly New Jersey while other reliably model guidance are into Eastern Long Island NY to the Connecticut/Rhode Island border through Connecticut or even into Eastern Rhode Island offshore of Long Island. This gives conflicting signals on the direct impacts to Southern New England but some will definitely occur. The severity of the impacts including the potential for tropical storm to possibly minimal category-1 hurricane potential remains but it is conflicted given the current model guidance. The headlines reflect the current watches, warnings and thinking. The key factors over the next several days are as follows:

1.) The track of Henri and whether a westward trend in the guidance continues or settles on the current track or if some eastward shifts occur. The west side of Henri will experience some strong winds with heavy rain as the main threat while closest to the center and on the east side of the system will have the greater potential for damaging winds, and severe weather but less rainfall. The track will also affect which coastal areas will have the greatest risk for coastal storm surge flooding. As mentioned above there is still spread in the guidance with conflicting signals regarding the impacts.
2.) The intensity and structure of Henri are additional factors. All models strengthen Henri significantly as it moves northward towards New England. Its peak intensity along with the size of the tropical storm force and hurricane force wind fields will also determine how strong the impacts are over the Southern New England coast and Southeast/Eastern New England.
3.) The speed of Henri’s approach to the region. Some models slow Henri’s approach toward Southern New England . Depending on when that slowing occurs and how close it is to the Southern New England coast will determine impacts over the region. Typically, tropical systems accelerate through Southern New England but the setup for Henri may actually have it slow near or over Southern New England or potentially south of New England. This might allow for more weakening of Henri due to cooler waters but could extend the impacts of the system over a longer duration and where it slows and how close it is to the region when it slows down will determine the extent of Henri’s impacts. Regardless of the speed, impacts in the area from heavy rainfall and flash flooding along and to the west of the track and damaging winds, severe weather and coastal storm surge flooding along and east of the track are likely.
4.) The potential for thunderstorms particularly along and to the east side of the track that can bring damaging winds down to the surface and the potential for isolated tornadoes will bear watching Sunday Morning through Sunday evening given the SPC marginal risk for severe weather in much of Southern New England.

SKYWARN Self-Activation is likely for the potential impacts of Henri for Sunday into Monday. ARES/RACES and other similar groups should closely monitor the progress of Henri and seek advice from their leadership. The next coordination message on Henri will be posted by 1100 PM Saturday Evening. Pictures, videos and post storm damage reports from Thursday’s severe weather event and upcoming impacts from Henri can be sent as a reply to this email, via our WX1BOX Facebook and Twitter feeds and through the email address pics@nsradio.org. Below is the NWS Boston/Norton Hurricane Local Statement, Flood Watch Statement, Area Forecast Discussion, Enhanced Hazardous Weather Outlook, SPC Day-2 Convective Outlook, Public Information Statement on Hurricane Safety Tips and the NHC Tropical Storm Henri advisory package:

NWS Boston/Norton Area Forecast Discussion:
https://kamala.cod.edu/ma/latest.fxus61.KBOX.html

NWS Boston/Norton Flood Watch Statement:
https://kamala.cod.edu/ma/latest.wgus61.KBOX.html

NWS Boston/Norton Hurricane Local Statement:
https://kamala.cod.edu/ma/latest.wtus81.KBOX.html

NWS Boston/Norton Enhanced Hazardous Weather Outlook:
https://www.weather.gov/box/ehwo

SPC Day-2 Convective Outlook:
https://www.spc.noaa.gov/products/outlook/day2otlk.html

NWS Boston/Norton Public Information Statement – Hurricane Safety Tips:
https://kamala.cod.edu/offs/KBOX/2108201412.nous41.html

National Hurricane Center – Miami Florida Information:

Tropical Storm Henri Public Advisory Information:
https://kamala.cod.edu/TPC/latest.wtnt33.KNHC.html

Tropical Storm Henri Technical Discussion Information:
https://kamala.cod.edu/TPC/latest.wtnt43.KNHC.html

Tropical Storm Henri Forecast/Advisory Information:
https://kamala.cod.edu/TPC/latest.wtnt23.KNHC.html

Tropical Storm Henri Wind Speed Probabilities:
https://kamala.cod.edu/TPC/latest.font13.KNHC.html

Tropical Storm Henri Key Messages:
https://www.nhc.noaa.gov/refresh/graphics_at3+shtml/092753.shtml?key_messages#contents

Tropical Storm Henri Storm Graphics:
https://www.nhc.noaa.gov/refresh/graphics_at3+shtml/092753.shtml?cone#contents

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
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