Expert forecasts for 2021 North Atlantic Hurricane Season

[cycloneye]

Here we go with the expert forecasts 2021 thread starting with TSR and CSU.

CSU

December 10 --- https://tropical.colostate.edu/Forecast/2020-12.pdf --- Outlook in general

April 8 ---

June 3 ---

August 5 ---

TSR

December 9 --- http://www.tropicalstormrisk.com/docs/T ... ec2021.pdf --- 16/7/3

April 9 ---

NOAA

[cycloneye]

Here are the possibilities.

1. AMO becomes very strong in 2021 and no El Niño occurs (resulting in a seasonal
average Accumulated Cyclone Energy (ACE) activity of ~ 170) – 25% chance.
2. AMO is above average and no El Niño occurs (ACE ~ 130) – 30% chance.
3. AMO is above average and El Niño develops (ACE ~ 80) – 15% chance.
4. AMO is below average and no El Niño occurs (ACE ~ 80) – 20% chance.
5. AMO is below average and El Niño develops (ACE ~ 50) – 10% chance.


Typically, seasons with the above-listed ACE values have TC activity as follows:
170 ACE – 14-17 named storms, 9-11 hurricanes, 4-5 major hurricanes
130 ACE – 12-15 named storms, 6-8 hurricanes, 2-3 major hurricanes
80 ACE – 8-11 named storms, 3-5 hurricanes, 1-2 major hurricanes
50 ACE – 5-7 named storms, 2-3 hurricanes, 0-1 major hurricane

[AnnularCane]

Wait a sec, I thought the CSU didn't do December forecasts anymore. Or am I thinking of something else?

[ouragans]

TSR was published yesterday

16 TS
7 H
3 IH

[CrazyC83]

If things don't change, 2021 could be another season of our worst nightmares. However, it's hard to imagine two consecutive insane seasons. Could 2006 be a potential analog for 2021? I think that will be thought of a lot.

[aspen]

If things don't change, 2021 could be another season of our worst nightmares. However, it's hard to imagine two consecutive insane seasons. Could 2006 be a potential analog for 2021? I think that will be thought of a lot.

We’ll need to see how fast the ENSO warms over the next 5-10 months. It’s going to warm at least somewhat, but we’re months away from the Spring Barrier, so we have essentially zero certainty as to what will have.

If we get a quickly warning ENSO, a 2006-like year is on the table. If we get an ENSO that barely warms and remains cool or neutral, another active season is likely.

[NorthieStangl]

If things don't change, 2021 could be another season of our worst nightmares. However, it's hard to imagine two consecutive insane seasons. Could 2006 be a potential analog for 2021? I think that will be thought of a lot.

That is a possibility, but the hyperactive 1995 season was followed by an active 1996, and an active 2004 was followed by 2005. Also, 2010 with 19 storms was followed by 2011 which also had 19 storms, which was followed by 2012 with, again, 19 storms.

[Category5Kaiju]

If things don't change, 2021 could be another season of our worst nightmares. However, it's hard to imagine two consecutive insane seasons. Could 2006 be a potential analog for 2021? I think that will be thought of a lot.

So this topic is quite a bit talked about in the "2021 Indicators" thread, but 2006 may actually not be a good analog for 2021 because if you really think about it, 2005 had a weak La Nina that rapidly and easily became an El Nino in 2006 whereas 2020's La Nina is way more robust and moderate, with historical records showing that years with a moderate La Nina onset are rarely (if ever) followed by an El Nino the year right after. 2006 was mainly inactive because of the El Nino, and I think it would be safe to say that given historical data as well as some long-range forecasts from various models and professional meteorologists that we will likely be neutral at most this season, 2021 could very well be more active than 2006. In other words, just because 2020 went Greek like 2005 does not mean 2021 will necessarily be the same as 2006 and be a weak season.

[chaser1]

This is the Expert Forecasts for 2021 North Atlantic thread, correct? Just wanted to make sure