Discussion About Changing the Start of the Atlantic Hurricane Season to May (15th)

[ClarCari]

NHC should not name marginal or questionable systems......MGC

See the issue with that is that it isn’t over for a storm till the fat lady sings. Systems that have had a wall of shear, pockets of dry air, and low sst’s can and have still managed to organize and later become devastating to areas.

To not name and monitor systems that are currently weak just because we presume it will 100% follow our predictions (orders?) would be highly irresponsible.

Fact is pre-season storms have a habit of spinning up abruptly and at times close to land, and $200 million damages and 20 deaths since only 2012 (which was noted on the WMO discussion about this issue) is no small number to those who were impacted by them.

[cycloneye]

If there is a change to May 15th, the S2K poll will start as always on April 1.

[wxman57]

We've always started our outlooks on May 15th, mainly to work out any bugs with deliveries & videos. The fact is that with changing naming policies and better detection available, more storms are being named prior to June 1. When I was a kid, the "A" storm was frequently not named until August. However with the addition of satellite data that first storm became earlier and earlier. Naming of subtropical storms and scatterometer data have moved the date earlier and earlier. I guess we'll need to start our outlooks on May 1st, then. But then, the NHC will probably need 4-5 years of "study" before they make the decision to start earlier to make sure there will be no issues.

In the end, it makes no difference at all. If a pre-season storm threat arises, then special outlooks are issued. If if something is developing in April, advisories are issued. June 1st is just a marker identifying when outlooks are issued daily.

[Kazmit]

Not only does it make sense as storms will continue to form earlier (and later) in the future, but it will also be synonymous with the EPac.

[Shell Mound]

This makes sense, meteorologically and practically. Meteorologically, many pre-June hurricanes and named storms were likely missed, prior to the 1980s and especially prior to the satellite era. Pre-June systems produced TS conditions over the CONUS in May 1908, May 1916, May 1951, May 1959, May 2007, May 2012, May 2015, and May 2018. Additionally, preliminary reanalysis indicates that a Category-2 hurricane, dubbed Amanda, made landfall in the Florida Panhandle at the close of May 1863. Furthermore, designating 15 May as the official start of the season gives coastal residents an additional head’s-up shortly prior to the start of summer vacation. I vote “hard” yes.

[Category5Kaiju]

I vote yes on this. The past 6 seasons have seen pre-season storms, but more importantly, the fact is that May 15 is also the start date for the EPAC season (so more consistency) and pre-season storms such as Alberto 2018 and Bertha 2020 did hit land and caused flooding, damages, and deaths (so more emphasis on the fact that such early storms are not rare and that they can still inflict loss of life and hazardous conditions). I feel it is better to give people advanced warning rather than be late and confuse them with the sense that late May storms are no big deal or cannot occur easily.


Btw, I know the WMO is planning on meeting online in mid-March and then have a much shorter part 2 meeting in May; while I know this will be presented in their March meeting, are they going to announce retired names from 2019 and 2020 in March as well?

[JetFuel_SE]

I vote yes on this. The past 6 seasons have seen pre-season storms, but more importantly, the fact is that May 15 is also the start date for the EPAC season (so more consistency) and pre-season storms such as Alberto 2018 and Bertha 2020 did hit land and caused flooding, damages, and deaths (so more emphasis on the fact that such early storms are not rare and that they can still inflict loss of life and hazardous conditions). I feel it is better to give people advanced warning rather than be late and confuse them with the sense that late May storms are no big deal or cannot occur easily.


Btw, I know the WMO is planning on meeting online in mid-March and then have a much shorter part 2 meeting in May; while I know this will be presented in their March meeting, are they going to announce retired names from 2019 and 2020 in March as well?

Yes, the schedule is public.

[AnnularCane]

A lot of you certainly made good arguments in favor of changing the date. Now you have me thinking it may not be a bad idea. Probably can't change my vote though, but oh well. Not sure I'd do it just yet anyway.

I still think it might be better to wait till next year though. I dunno, maybe give everyone time to get used to a new start date? (Or at least me? )

[jasons2k]

I’m for it. A lot of local media issue their tracking maps, supply lists, public service announcements, etc. on June 1st. I’m in favor of getting prepared early and ahead of time, so move it into May in case there is an early season storm.

[weathaguyry]

It seems almost every year the Atlantic wants to throw us something in the second half of May. The EPac season already starts May 15th, and is already under NHC jurisdiction, so why not start them both at the same time. I feel that the increased quality of satellite imagery over the past 10 years, with perhaps more relaxed naming standards, has allowed for the detection of broad/weak circulations in storms that would have been mostly passed over by the NHC in the 70’s or 80’s.

[weeniepatrol]

 https://twitter.com/TheSteveCop/status/1366736711712145409

[AnnularCane]

All I see is that they're starting the outlooks on the 15th, which I think we knew already. I don't see anything about the actual season starting then.

[cycloneye]

All I see is that they're starting the outlooks on the 15th, which I think we knew already. I don't see anything about the actual season starting then.

You are right. It will be decided during the WMO meeting.

[wxman57]

I see this as a solution without a problem. There is no problem in keeping things as they are. IF there is a tropical disturbance that develops out of the pre-defined season, then the NHC can simply initiate daily outlooks for the disturbance. These can be issued as often as is deemed necessary. Advisories would be issued as they normally would be for an "in-season" storm. No one is left un-warned.

[mitchell]

I see this as a solution without a problem. There is no problem in keeping things as they are. IF there is a tropical disturbance that develops out of the pre-defined season, then the NHC can simply initiate daily outlooks for the disturbance. These can be issued as often as is deemed necessary. Advisories would be issued as they normally would be for an "in-season" storm. No one is left un-warned.

I see it a bit differently, only in terms of communicating risk - not the science part. When the "official season" begins on June 1, and systems frequently develop earlier (8 out of the last 20 years) it creates the impression ((rightly or wrongly) that the early system is unexpected, rare, or indicative of some unusual weather pattern, climate change trend, or forecasting uncertainty. I would argue it is complicated enough to communicate with the public about tropical weather risk, so eliminating any sources of confusion, skepticism, or excuse for unpreparedness is worthwhile. It helps that I don't see any downside to the 15 day adjustment. Is there a downside?

[wxman57]

I see this as a solution without a problem. There is no problem in keeping things as they are. IF there is a tropical disturbance that develops out of the pre-defined season, then the NHC can simply initiate daily outlooks for the disturbance. These can be issued as often as is deemed necessary. Advisories would be issued as they normally would be for an "in-season" storm. No one is left un-warned.

I see it a bit differently, only in terms of communicating risk - not the science part. When the "official season" begins on June 1, and systems frequently develop earlier (8 out of the last 20 years) it creates the impression ((rightly or wrongly) that the early system is unexpected, rare, or indicative of some unusual weather pattern, climate change trend, or forecasting uncertainty. I would argue it is complicated enough to communicate with the public about tropical weather risk, so eliminating any sources of confusion, skepticism, or excuse for unpreparedness is worthwhile. It helps that I don't see any downside to the 15 day adjustment. Is there a downside?

Why not start the season in March or April? We've had subtropical storms prior to May 15. Again, if there is ANY kind of a tropical threat identified in the tropics prior to June 1st, those threats will be covered by outlooks and advisories. The downside might be sending out outlook after outlook saying there are still no disturbances in the tropics. That would not help risk managers, and I deal with many risk managers. Also, it would require a 24-hr shift at NHC starting May 15th. I would assume that they aren't fully-staffed 24 hours a day out of season. That's not much of a downside, but I see no benefit in changing the date of the start.

One other thing is that June 1 is the start of hurricane season. How many hurricanes have formed in the past 10 years prior to June 1? The only hurricane I could find was Alex of 2016 that formed (transitioned from an ET storm to a hurricane) on January 14th. Maybe the HURRICANE season should start January 1? Hurricanes occasionally form in the East Pacific prior to June 1st, which is why the season there starts before the Atlantic.

Oh, well, since the decision has been made, we'll be moving the start of OUR outlooks to May 1st. Need a couple weeks of testing and adjusting our database for bad emails before May 15th.

[Hurricanehink]

I see this as a solution without a problem. There is no problem in keeping things as they are. IF there is a tropical disturbance that develops out of the pre-defined season, then the NHC can simply initiate daily outlooks for the disturbance. These can be issued as often as is deemed necessary. Advisories would be issued as they normally would be for an "in-season" storm. No one is left un-warned.

I see it a bit differently, only in terms of communicating risk - not the science part. When the "official season" begins on June 1, and systems frequently develop earlier (8 out of the last 20 years) it creates the impression ((rightly or wrongly) that the early system is unexpected, rare, or indicative of some unusual weather pattern, climate change trend, or forecasting uncertainty. I would argue it is complicated enough to communicate with the public about tropical weather risk, so eliminating any sources of confusion, skepticism, or excuse for unpreparedness is worthwhile. It helps that I don't see any downside to the 15 day adjustment. Is there a downside?

Why not start the season in March or April? We've had subtropical storms prior to May 15. Again, if there is ANY kind of a tropical threat identified in the tropics prior to June 1st, those threats will be covered by outlooks and advisories.

(Snipped)
Given the combined four storms on record for March and April, those months definitely aren’t part of any sort of “season.” You could argue May 1, since we did have Ana a few years back hitting the US, but that would be adding extra resources. I think May 15 works well because it is before Memorial Day Weekend, and I think the US could do with more (and earlier) ocean preparedness. Any time there is a storm near the US, they get a lot of attention, and yet almost inevitably there are swimmer casualties. I think it makes sense starting warnings, and hopefully getting more info out there, in advance of the summer tourism season. That starts in mid May where I am from in New Jersey.

[CyclonicFury]

With Ana's formation, that marks the 12th time a subtropical or tropical cyclone formed in May since 2007.

2007 - SS Ana
2008 - TS Arthur
2009 - TD One
2012 - TS Alberto
2012 - TS Bill
2015 - TS Ana
2016 - TS Bonnie
2018 - TS Alberto
2019 - SS Andrea
2020 - TS Arthur
2020 - TS Bertha
2021 - TS Ana

Of these storms, 9 were tropical storms, 2 were subtropical storms, and 1 was a tropical depression.

It is interesting how, despite the early activity in weaker short lived storms, the prevelence of early-season hurricanes seems to have not changed. No May hurricanes have formed since 1970, and only 3 June hurricanes have formed since 1995.

[Shell Mound]

It is interesting how, despite the early activity in weaker short lived storms, the prevalence of early-season hurricanes seems to have not changed. No May hurricanes have formed since 1970, and only 3 June hurricanes have formed since 1995.

This is often used as an argument in opposition to naming these short-lived, pre-season (sub-)tropical storms, given that doing so skews the historical database.

[Nimbus]

There were likely many more May low level circulations before Satellite observations like the one in the gulf last week which never had much of a chance to make it to even TS strength. Hurricane Alma had some dangerous winds but that is rare. Shifting the start of the season to May 15th might provide some additional training invests. Would they consider this a waste of resources that could be better used in the peak of the hurricane season?