Tropical storm HEMRI ….soon to be Hurricane HENRI is now a HIGH PROBABILITY to impact he Northeast US coast , from NYC to Boston this weekend. HENRI will likely be weakening at the time of landfall but the track of HENRI, from South to Northwest will drive a much higher than normal storm tides INTO to coastal areas.

In addition, the combination of the Full Moon and the numerous concave shapes of the coastal areas From New York City to Cape Cod and Boston Bay will also enhance the potential storm tide and will likely produce much more significant coastal flooding than one might see with a weakening hurricane or garden-variety tropical storm on the northeast US Coast.

Tropical storm HENRI continues to slowly strengthen as it moves slowly northward paralleling the southeast US Coast. Max winds and now up to 70 MPH and it is quite likely that HENRI will reach hurricane intensity tonight or early Saturday morning. The satellite pictures show a fairly well-developed strengthening strong tropical storm and the various weather models are in very good agreement about what’s going to happen over the next 48 hours.

We begin with this surface image which shows the position of a cold front off the coast and tropical storm HENRI. Normally, such a cold front would turn any Tropical Cyclone regardless of size or intensity, out to sea. But in this particular case there is a complication. As we talked about in the previous reports, the main concern is the formation of a closed UPPER LOW in the jet stream that is going to form in Ohio and West Virginia by Saturday morning.

As HENRI comes up the coast, the closed Upper LOW in West Virginia will move into Virginia and Pennsylvania where it will capture HENRI and pull it to the Northwest, bringing the system INTO coastal New England. There is some uncertainty as to where HENRI will make an actual landfall. It could be Cape Cod Massachusetts , Rhode Island, eastern Long Island or western /central Connecticut. However at this point in time the key thing to mention is that the turn to the Northwest into the coast has been the trend on all the models since Thursday night and the agreement is quite strong. The turn to the Northwest, while unusual, has happened before. You may recall the track that Hurricane Sandy took back in October 2012.

***** Of course Sandy was a much larger hurricane that was far more powerful and had a much more massive storm surge associated with it. So one has to be careful in drawing an analogy or a comparison between these two tropical Cyclones but HENRI’s turn to the Northwest does have s SOME…SOME similarity to what we saw with Sandy in October 2012. ****

Earlier in the week, there was some uncertainty as to whether or not a closed UPPER LOW in the Middle Atlantic region would capture HENRI and pull it to the west and if so but how much. But as we can now see all the models have turned strongly towards a solution.

Here we compare the 12z midday hurricane models to the 18z (6 PM) run and there is amazingly strong agreement in these models. Notice the significant shift here in the last 18 to 24 hours with most of the hurricane tracks now showing landfall west of Cape Cod across Central and Western Long Island and possibly into Connecticut. This trend is very hard to discount given the amazingly strong model agreement we are saying across the board.

Here we can look at the GFS and the European ensembles also from the midday Friday model run. The thick black line represents the mean of all these different samples. The GFS has 20 different members in its ensemble, while the European model has 50 members. In both cases, 50% of the members are further to the west of the black line and 50% are to the east.

In other words, it is possible that we could see a very sharp turn to the northwest with HENRI so that it could end up tracking into western Long Island and/or close to New York City. However, the vast majority of the data does not show a Track that far to the West.

Perhaps the most aggressive of all of the large-scale and well-known models and hurricane models is the British model (UKMET). It was the first model to show HENRI would get captured by the UPPER LOW and get pulled to the West and it has been the most aggressive of all the models with the turn to the Northwest.

This image shows the early Friday (00z) morning British model. Note the sharp turn to the northwest with landfall in western Long Island, passing just to the east of New York City up into the lower Hudson Valley by Sunday night.

The updated midday British model (12z) continues that trend but has an even sharper turn to the northwest making landfall in western Long Island and New York City and tracking up into the lower Hudson Valley.

The history of hurricanes along the East coast shows that the worst Destruction and the biggest problems occur when the hurricanes parallel the East coast and then turn INTO the coastal areas. We saw this with Hurricane Sandy in October 2012. The turn to the northwest takes the storm surge… which is usually on the eastern side of the hurricane… nd drives it INTO the coast. In addition, along the Northeast coast, there are a lot of locations where the coastal areas and the bays, with smaller and narrower openings. cause the water to pile up. The result is a much bigger storm surge. This has been modeled quite well by many of the hurricane models and research over the past decades and we saw this happen with Hurricane Sandy in October 2012. The storm surge in New York Harbor end Coast New Jersey as well as West Long Island was several feet higher than with the models at forecasting.

As we discussed before… HENRI will be arriving at the time of Full moon and high tide. The track of Henri turning to the northwest will result in East and Southeast winds that will drive the Atlantic Ocean into the southern coast of Massachusetts, Rhode Island, Connecticut, the Long Island Sound, as well as New York Harbor. For all of these reasons, the potential storm-surge is much more significant than it normally would be with a weakening hurricane or a song tropical storm.

The one think that seems to be of some help ss that the hurricane forecast intensity models show steady weakening as the hurricane approaches the coast on Sunday. As you can see from this image, these models are forecasting HENRI to make hurricane intensity on Saturday but then they all show steady weakening Saturday night and Sunday before landfall. Some of these models show tropical storm winds no greater than 50 knots by the time HENRI reaches the Coast. This would be good news with respect to the storm surge.

A decrease in the wind speeds would have it bigger impact inland where the friction of the land surfaces would also reduce the wind speeds to a significant degree and caused much less damage to the power infrastructure in northern New Jersey …New York City metro area…Southeast New York… Connecticut … Rhode Island and Massachusetts.



Meteorologist ... Atheist.. Dyslexic ..Baseball.. Fat tail distributions ..Good Judgement Projection… Black Swans/ Taleb …Choas / non Linear Dynamics… ENTP

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DT Wxrisk

Meteorologist ... Atheist.. Dyslexic ..Baseball.. Fat tail distributions ..Good Judgement Projection… Black Swans/ Taleb …Choas / non Linear Dynamics… ENTP