Hurricane Zeta could link up with a cold front, bringing snow to New England

It was quite the dreary Monday across the region, with clouds hanging tough all day in combination with the cool temperatures. I wish I had better news for tomorrow, but even if the low clouds dissipate, I still think we’re going to contend with a mainly cloudy morning. Finally, we have the chance for some sunshine trying to develop tomorrow afternoon.

Clouds continued to stream north Monday afternoon.
Clouds continued to stream north Monday afternoon.COD Weather

There will actually be even cooler air filtering in throughout the afternoon, so temperatures will hold in the 40s over inland areas, but eventually make it into the 50s right along the coastline. Think of tomorrow as perhaps feeling a little bit better, if we can get the sunshine, even though temperatures will be quite similar.

High temperatures Tuesday will reach only the lower to middle 50s.
High temperatures Tuesday will reach only the lower to middle 50s.NOAA

Wednesday is definitely my pick of this work week. On that day there’s no chance of any rain – we’ll see sunshine blended with clouds basically all day long and temperatures will be seasonable. This will be a wonderful day to get outside and enjoy late October weather and take advantage of the last few days of daylight saving time.

While all of this is going on, a hurricane is going to be traveling across the Gulf of Mexico and eventually hit the Gulf Coast as a category one storm.

Here in New England we have missed all the tropical activity in this very active season. Frankly it’s pretty amazing to me that in spite of the fact that we’ve had so many tropical systems – a record-breaking amount even – we haven’t had anything to write home about here.

First and foremost, we still will not be hit with a hurricane. Zeta will have weakened to a breezy rainstorm by Thursday night and Friday. Unlike many other tropical systems, the moisture from Zeta will make it into New England by Friday. Some of the rainfall could be heavy.

Rain, which may be heavy, will move through New England early Friday and may be mixed with snow.
Rain, which may be heavy, will move through New England early Friday and may be mixed with snow.COD Weather

The atmosphere this time of the year is in flux, and the northern part of the jet stream over us often pushes any tropical waves out to sea before they ever get here. While the remnants of Hurricane Zeta are moving along the Appalachians, a cold front will be sweeping east. These two weather systems will interact in such a way that the storm’s moisture will be pulled northward at the same time colder air is moving in on the back side.

Snow is possible Friday as colder air filters into the region behind Hurricane Zeta.
Snow is possible Friday as colder air filters into the region behind Hurricane Zeta.WeatherBell

This combination has the potential to yield our first flakes of snow and light accumulation, especially across the Worcester hills and the Berkshires. There will be some heavy rain over eastern areas and this could end as some wet snow even close to Route 128. It’s less likely Greater Boston sees snow, but not impossible. We

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Zeta May Be Forming In The Caribbean

The 2020 Atlantic hurricane season is still upon us. Hurricane Epsilon is heading off into the North Atlantic, but there is no rest for hurricane forecasters. The National Hurricane Center is now watching a new area of interest in the Caribbean Sea. If it develops into a tropical storm, it will be named Zeta. Would it be odd for this time of year? The answer is complicated.

Before I delve into the answer, let’s take a look at the current status of Invest #95L, the technical name given to the storm system of interest by NOAA. According to the National Hurricane Center Friday afternoon update, “Satellite images and radar data indicate that the broad area of low pressure located just west of Grand Cayman Island is gradually becoming better defined.” Forecasters give the storm a 70% chance of further development within the next 2 to 5 days. Whether it becomes Zeta or not, significant rainfall will be possible over the weekend in Cuba, Jamaica, southern Florida, and parts of the Bahamas. The ultimate path of the storm (towards Florida or further into the Gulf of Mexico) will depend on how it interacts with a cold front sweeping eastward in the United States. If you live in Florida or along the eastern Gulf of Mexico, watch the forecast carefully over the weekend.

Ok, let’s get to the question about “odd.” It is certainly not odd to have tropical cyclones at this time of year. The map below shows a climatology of tropical cyclone origin points in late October over the period 1851 to 2015. If Zeta forms, it is within a region of the Atlantic basin where we tend to see development. However, here is where things get a bit more complicated.

If Zeta forms, it will be only the second time in history that we have used the name Zeta. That is odd. As you recall, when the hurricane name list is exhausted, the Greek alphabet is used. The only other time this was employed was 2005. That year, Zeta, which is not the last letter in the Greek Alphabet, was reached. There is one major difference between 2005 and 2020. In 2005, Tropical Storm Zeta was named on December 30th and dissipated in January. According to a Tweet by Colorado State University hurricane expert Phil Klotzbach, “Current record for earliest 27th Atlantic named storm formation is November 29, 2005” He goes on to explain that the previous record was for the 2005 version of Epsilon but an additional October storm was added after the season in 2005. This oddity explains why the 27th named storm was Epsilon in 2005. The 27th named storm in 2020 will be Zeta (if it develops).

In a season of records for the 2020 Atlantic hurricane season, CIRES research scientist Sam Lillo points out another

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Caribbean storm could become Tropical Storm Zeta

Air Force Reserve Hurricane Hunters were dispatched to fly into and investigate the system Friday afternoon, which may give models a better idea of where this storm could be headed.

If the disturbance does get a name, though, which appears increasingly likely, it would tie with 2005 for the greatest number of named storms to ever occur in a hurricane season. Any storms beyond that would bring us deeper into the Greek alphabet than we’ve ever gone before.

Shortly after lunchtime on Friday, heavy showers and thunderstorms were affecting the southern coast of Cuba and western Jamaica. The system’s center of circulation was located about 100 miles south of the Cayman Islands.

The Cayman Islands’ weather agency warned of “possible flooding of low lying areas” with heavy downpours bubbling up across the island.

On infrared satellite imagery, a pinwheel of showers and thunderstorms could be seen slowly orbiting about a common center. The system appeared rather balanced, meaning that thunderstorm activity was present all around the low-level center. This could help it to organize a central vortex and jump-start the process of intensification.

The system has exhibited healthy outflow of air aloft, which is suggestive of a strengthening storm. Outflow is essentially the “exhaust” of a tropical weather system, such as a hurricane. The more efficiently it can evacuate spent air up out of and away from it, the easier it is for the storm to pump in moisture-rich air at the surface and intensify.

The jury is out when it comes to the computer models and whether Invest 95L will end up intensifying. The models, however, have struggled to even “keep up” with real-time observations, forcing forecasters to rely more on experience.

The most likely scenario would be for the system to slowly consolidate, becoming a depression or named tropical storm, Zeta, before passing over Cuba this weekend. Heavy rain would be possible for the Cayman Islands and southern Cuba during this time frame.

Then an inflection point in the system’s intensity would be reached on Sunday as it encounters two obstacles at the same time. The first will be its passage near or over Cuba, which could disrupt the circulation.

At the same time, wind shear, which is the change in wind speed and/or direction with height, from a weak cold front passing through could impede the storm. Too much shear can induce weakening.

In the event it holds together or is able to re-intensify after a passage over land, heavy rain will be possible over Florida. Ocean heat content, a metric that describes how much energy is contained in near-surface ocean waters to sustain a storm, is low across most of the Gulf of Mexico — except for north of the western tip of Cuba and around the Straits of Florida. There is a low chance that Zeta could become a hurricane, a scenario shown by one or two computer models.

The bottom line? Hurricane season isn’t over until it’s over (officially that’s Nov. 30), and this

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