Expert forecasts for the 2017 North Atlantic Hurricane Season

[tolakram]

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Colorado State University (CSU)

December 14th - https://webcms.colostate.edu/tropical/media/sites/111/2016/12/2016-12.pdf | QUALITATIVE DISCUSSION

April 6th - http://webcms.colostate.edu/tropical/media/sites/111/2017/04/2017-04.pdf 11/4/2 with ACE of 75

June 1 - http://webcms.colostate.edu/tropical/media/sites/111/2017/06/2017-06.pdf 14/6/2 with ACE of 100

July 5th - http://webcms.colostate.edu/tropical/media/sites/111/2017/07/2017-07.pdf 15/8/3 with ACE of 135

August 4th - http://webcms.colostate.edu/tropical/media/sites/111/2017/08/2017-0804.pdf Two Week Forecast (4-17)

November 30 - https://tropical.colostate.edu/media/sites/111/2017/11/2017-11.pdf - Verification of Forecasts

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Tropical Storm Risk (TSR)

December 14th - http://tropicalstormrisk.com/docs/TSRATLForecastDec2017.pdf | 14/6/3

April 5th - http://tropicalstormrisk.com/docs/TSRATLForecastApr2017.pdf - 11/4/2

May 26 - http://www.tropicalstormrisk.com/docs/TSRATLForecastPreSeason2017.pdf - 14/6/3

July 4th - http://tropicalstormrisk.com/docs/TSRATLForecastJuly2017.pdf 17/7/3

August 4th - http://tropicalstormrisk.com/docs/TSRATLForecastAug2017.pdf 17/7/3

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[tolakram]

A graph from the TSR forecast gives a good measure of how little skill these early forecasts have plus how well TSR has done compared to other forecasts.

[Steve]

Joe Bastardi threw out some comments in this weekend's update. He thinks it will be a lower ACE season, but due to record warmth in the Gulf and also likely high heat content near the US East Coast, they believe the entire coast is vulnerable this year in a take them as they come season as opposed to last year that keyed more on the SW Atlantic. I don't have an opinion on the comments.

He said they also believe there will be a wild March and a busy severe storm season in the spring.

[JaxGator]

Joe Bastardi threw out some comments in this weekend's update. He thinks it will be a lower ACE season, but due to record warmth in the Gulf and also likely high heat content near the US East Coast, they believe the entire coast is vulnerable this year in a take them as they come season as opposed to last year that keyed more on the SW Atlantic. I don't have an opinion on the comments.

He said they also believe there will be a wild March and a busy severe storm season in the spring.

Sounds like a somewhat of a repeat of last year, but we'll see. We're still recovering from the last one. Our winter has been chilly (like close to or under freezing on some days), but it doesn't last long. I think Joe might be on to something with this upcoming spring storm season as it might be a big one. The tornado outbreaks close to home and squall lines that have come through this winter storm season might (and I say might) be a harbinger for things to come.

[Steve]

We had a brief cold shot in December, but this is one of our warmest winters in forever. That's fine with me. But much of the cold has been more angled toward y'all on a SE slant before lifting out. As you know, often where noses of winter troughs point will indicate potential alleys later. What I got from the segment was that he felt like we were going to have some in close development but the distribution would be less concentrated than 2016 which of course was your year in a way 2002 and 2005 were ours.

[cycloneye]

CSU has a new co-author to their outlooks (MIchael Bell)

http://source.colostate.edu/csu-tropica ... hael-bell/

[Steve]

More Joe B and Weatherbell - starts at 7:20 on the Saturday Summary

Tricky Forecast this year. Not a non-season though. Target areas are Mouth of the MS down to Vera Cruz and then from the GA Coast up to New England and East of that. They have much below in the MDR. Their worry is quick developing in close.

10-12 NS
4-6 H
1-2 IH
ACE 75-95

[TheStormExpert]

More Joe B and Weatherbell - starts at 7:20 on the Saturday Summary

Tricky Forecast this year. Not a non-season though. Target areas are Mouth of the MS down to Vera Cruz and then from the GA Coast up to New England and East of that. They have much below in the MDR. Their worry is quick developing in close.

10-12 NS
4-6 H
1-2 IH
ACE 75-95

Do you know what his reasons are behind these target areas?

[Steve]

More Joe B and Weatherbell - starts at 7:20 on the Saturday Summary

Tricky Forecast this year. Not a non-season though. Target areas are Mouth of the MS down to Vera Cruz and then from the GA Coast up to New England and East of that. They have much below in the MDR. Their worry is quick developing in close.

10-12 NS
4-6 H
1-2 IH
ACE 75-95

Do you know what his reasons are behind these target areas?

I don't subscribe to them so I don't have his exact reasoning. I understand why they don't believe the MDR will be active. Water is cool and pressures should be high. But as for the red in the west and sw Gulf as well as along and east of the US East Coast, I think it's the water temperature profiles in conjunction with what they probably think the El Niño is going to do. I think their numbers are good though. They might be slightly low on ACE but they also could be high were the season to shut down due to Pacific heat. It's April so we can watch the evolution in the Spring and see how things evolve.

[wxman57]

Do you know what his reasons are behind these target areas?

It's the fact that the Main Development Region (deep tropics between the eastern Caribbean & Africa) is expected to be quite unfavorable again this season for long-tracked storms. When the storms fail to develop/intensify in the MDR, they tend to form and track farther west toward the NW Caribbean, Gulf, and north of the Bahamas.

[cycloneye]

Here is the graphic from JB of his forecast.

[Alyono]

is there a year that Bastardi does not forecast above average activity for New England?

[tolakram]

Not that I'm aware.

Here's a snip of text from his forecast discussion.

The number I have now for the ACE (Accumulated Cyclone Energy) is 75-95, but over half of that ACE may be to the north of 25°N and to the west of 65°W. The danger of an El Niño season in spite of overall lower numbers is well known, with some huge names showing up. Of major interest is the lack of tropical activity in the Southern Hemisphere, with ACE at less than 30% of normal at a time when activity is typically over 85% done. Years with an ACE under 200 in the Southern Hemisphere have averaged 77 in the western Atlantic, but some big years showed up like 1995. However, if we just look at years when an El Niño came on, with a lack of activity, they were under 50!

[cycloneye]

 https://twitter.com/philklotzbach/status/849279399694278657

[cycloneye]

Tropical Storm Risk (TSR) April 5 forecast=11/4/2 ACE 67.They are banking on El Nino in a Moderate stage coming and that is why the low numbers.

The TSR (Tropical Storm Risk) April forecast update anticipates North Atlantic hurricane activity in 2017 will be below-norm. Based on current and projected climate signals, Atlantic basin tropical cyclone activity is forecast to be about 30% below both the 1950-2016 long-term norm and the recent 2006-2015 10-year norm. The forecast spans the period from 1st June to 30th November 2017 and employs data through to the end of March 2017. The reason why the TSR forecast for North Atlantic hurricane activity in 2017 has fallen by 30% since the TSR extended range outlook issued in December 2016 is the anticipated development of a moderate El Niño by the summer/autumn of 2017. This El Niño development was not foreseen in December 2016. Should the TSR forecast for 2017 verify it would mean that the ACE index total for 2013-2017 would be easily the lowest 5-year total since 1990-1994, and would be equivalent to a typical 5-year total experienced during the inactive phase of Atlantic hurricane activity between 1970 and 1994.

http://tropicalstormrisk.com/docs/TSRAT ... pr2017.pdf

[wxman57]

Klotzback will present his outlook tomorrow at the National Tropical Weather Conference on S. Padre Island, TX. I know his numbers, as we've been discussing it. There is a BIG question as to the development (or not) of a moderate El Nino. The MDR does look like it may be hostile again this season. What the heck is going on there?

[WeatherEmperor]

Klotzback will present his outlook tomorrow at the National Tropical Weather Conference on S. Padre Island, TX. I know his numbers, as we've been discussing it. There is a BIG question as to the development (or not) of a moderate El Nino. The MDR does look like it may be hostile again this season. What the heck is going on there?

I posted in the ENSO thread about the sub surface Epac temps not supporting a developing El Nino despite the temps at the surface showing that Nino is developing. Can you head over the the Enso thread and discuss this? I feel like if the sub surface continues to show more cooler waters we may get an aborted El Nino event much like 2014.


Sent from my iPhone 7 using Tapatalk

[Hurricaneman]

Klotzback will present his outlook tomorrow at the National Tropical Weather Conference on S. Padre Island, TX. I know his numbers, as we've been discussing it. There is a BIG question as to the development (or not) of a moderate El Nino. The MDR does look like it may be hostile again this season. What the heck is going on there?

I posted in the ENSO thread about the sub surface Epac temps not supporting a developing El Nino despite the temps at the surface showing that Nino is developing. Can you head over the the Enso thread and discuss this? I feel like if the sub surface continues to show more cooler waters we may get an aborted El Nino event much like 2014.


Sent from my iPhone 7 using Tapatalk

Or even 2012 which was another aborted El Niño

[tolakram]

 https://twitter.com/philklotzbach/status/849984539732713472




Direct Link: http://webcms.colostate.edu/tropical/media/sites/111/2017/04/2017-04.pdf

[King-6]

Under forecast...
Check 12 years back and 12 years back and 12 years back and 12 years back and 12 years back ect...