Expert forecasts for 2020 North Atlantic Hurricane Season

[USTropics]

I’d love to know NCSU’s methodology as well as everyone going bullish.. also, does 22 imply we get to W? I’m pretty sure that’d be a 2nd place finish for a season in the Atlantic, before 1933 in 3rd and obviously after 2005 in 1st

22 would get us to Alpha (there are only 21 names per list in the Atlantic).

The TD;DR of the reasoning for these bullish forecasts is because of warmer than average SSTs (especially in the Gulf), possible high moisture and low shear in the Main Development Region, and signs that the ENSO will progress from a weak El Niño to a La Niña by the peak of the season.

I know it's natural to have a focus on SST this this time of year, but we all know the the SAL is the biggest detriment to development especially in the MDR. Seems it is present every year in the summer.
Are there any predictions for the Easterly trade winds and Sarahan precip patterns being any different than a typical season?

We can look for pattern similarities using long range models. Below is a composite for 8/10 of the most active years in the Atlantic (1926, 1933, 1950, 1961, 1995, 1998, 2004, 2005) and what precipitable patterns looked like for Africa during the months of June-September.


Below is the latest CFS prediction for August 2020, which is in accordance with a forecasted active WAM:

[BYG Jacob]

So, to sum up everything so far, we're in trouble

[JPmia]

Anyone post this one?

http://www.essc.psu.edu/essc_web/research/Hurricane2020.html

"The prediction is for 19.8 +/- 4.4 total named tropical cyclones, which corresponds to a range between 15 and 24 storms, with a best estimate of 20 named storms."

[cycloneye]

Anyone post this one?

http://www.essc.psu.edu/essc_web/research/Hurricane2020.html

"The prediction is for 19.8 +/- 4.4 total named tropical cyclones, which corresponds to a range between 15 and 24 storms, with a best estimate of 20 named storms."

Thanks for posting it. Is now on the first post list.

[chaser1]

Anyone post this one?

http://www.essc.psu.edu/essc_web/research/Hurricane2020.html

"The prediction is for 19.8 +/- 4.4 total named tropical cyclones, which corresponds to a range between 15 and 24 storms, with a best estimate of 20 named storms."

I enjoy reading other expert seasonal predictions. I took the time to click the link and read it's details. The manner in which they reached their (quasi) prediction and range of outcomes kind of left me .....

[Steve]

Anyone post this one?

http://www.essc.psu.edu/essc_web/research/Hurricane2020.html

"The prediction is for 19.8 +/- 4.4 total named tropical cyclones, which corresponds to a range between 15 and 24 storms, with a best estimate of 20 named storms."

I enjoy reading other expert seasonal predictions. I took the time to click the link and read it's details. The manner in which they reached their (quasi) prediction and range of outcomes kind of left me .....

It's Penn State University. Doctor Mann is one of the greats. What they're saying is that if we don't go la nina and stay cool neutral, then the number comes down slightly (+/- 1NS). They only showed three assumptions - SSTA's in the MDR, mild negative ENSO and future NAO. Oh nevermind, you clicked on the .PDF's. haha. Yeah, I'm sure it's as basic as nursery rhymes for some, but I see what you're saying. haha

Another solid and reputable entity in Penn State is coming out with a gangbuster season. They show skill in their previous forecasts back through 2007, but the 3 years they missed the worst, they under-forecast their best guess: 2012 (10, we got 19NS), 2018 (10 we had 15) and 2019 (10 we had 18).

So yeah, another ominous forecast.

[Shell Mound]

Not one of Crown Weather's analog seasons matches any of ours, which include 1966, 1967, and 1977. I'm thinking fewer storms in the subtropics this season, which runs against 1995 tracks. MDR still fairly hostile, too. Our analogs average 9-10 named storms, but you have to add on 4-5 to account for all the short-lived, subtropical storms, and occluded lows that may get named.

I have a feeling that your forecast will end up far closer to the truth than most of the other professionals’ and laymen’s. The +AMO has ended. We’ll see.

[CyclonicFury]

Not one of Crown Weather's analog seasons matches any of ours, which include 1966, 1967, and 1977. I'm thinking fewer storms in the subtropics this season, which runs against 1995 tracks. MDR still fairly hostile, too. Our analogs average 9-10 named storms, but you have to add on 4-5 to account for all the short-lived, subtropical storms, and occluded lows that may get named.

I have a feeling that your forecast will end up far closer to the truth than most of the other professionals’ and laymen’s. The +AMO has ended. We’ll see.

No it hasn't. The Atlantic has met NOAA's above-normal definition for four consecutive seasons, which it failed to do ONCE during the last -AMO period from 1970-94.

Here's what NOAA said in their hurricane season forecast last year.
Conditions over the eastern MDR and western Africa favor increased activity, and are associated with the ongoing high-activity era for Atlantic hurricanes that began in 1995 (Goldenberg et al. 2001, Bell and Chelliah 2006, Klotzbach and Gray 2008).

[cycloneye]

NHC forecaster Daniel Brown confirmed that NOAA will release their outlook on May 21.

[USTropics]

Klotzbach believed we may have been ending the positive phase of the AMO after the 2013-2015 hurricane seasons. He has since begun to back off that assessment in his recent seasonal forecasts:

Four above-average seasons lends confidence that the AMO remains in a positive phase, although the far North Atlantic has generally been characterized by below-average sea surface temperatures (SSTs). One of the primary physical drivers for active versus inactive Atlantic basin hurricane seasons is the strength of the AMO (Gray et al. 1996, Goldenberg et al. 2001, Klotzbach and Gray 2008). A positive phase of the AMO (or strong phase of the THC) typically leads to 3-5 times more major Atlantic basin hurricane activity than does a negative phase. The typical period of the AMO is about 60 years, with the period length varying between as short as 40-50 years and if 70-80 years. This means that we typically have 25-35 years of above-average Atlantic basin major TC activity and similar length periods with considerably reduced amounts of major TC activity. Recently, we had three quiet Atlantic hurricane seasons in a row (e.g., 2013-2015) which led us to question whether we had moved out of the active era that began in 1995 (Klotzbach et al. 2015). However, the Atlantic has since had four active seasons in a row, which makes an assessment of whether we have moved out of the active Atlantic hurricane era quite murky.

Another clue that we're still in the positive phase of the AMO - shortened El Nino phases (like the one that is currently ending) are frequent, whereas a negative AMO phase we would see prolonged El Nino events.

[Monsoonjr99]

Klotzbach believed we may have been ending the positive phase of the AMO after the 2013-2015 hurricane seasons. He has since begun to back off that assessment in his recent seasonal forecasts:

Four above-average seasons lends confidence that the AMO remains in a positive phase, although the far North Atlantic has generally been characterized by below-average sea surface temperatures (SSTs). One of the primary physical drivers for active versus inactive Atlantic basin hurricane seasons is the strength of the AMO (Gray et al. 1996, Goldenberg et al. 2001, Klotzbach and Gray 2008). A positive phase of the AMO (or strong phase of the THC) typically leads to 3-5 times more major Atlantic basin hurricane activity than does a negative phase. The typical period of the AMO is about 60 years, with the period length varying between as short as 40-50 years and if 70-80 years. This means that we typically have 25-35 years of above-average Atlantic basin major TC activity and similar length periods with considerably reduced amounts of major TC activity. Recently, we had three quiet Atlantic hurricane seasons in a row (e.g., 2013-2015) which led us to question whether we had moved out of the active era that began in 1995 (Klotzbach et al. 2015). However, the Atlantic has since had four active seasons in a row, which makes an assessment of whether we have moved out of the active Atlantic hurricane era quite murky.

Another clue that we're still in the positive phase of the AMO - shortened El Nino phases (like the one that is currently ending) are frequent, whereas a negative AMO phase we would see prolonged El Nino events.

Can you explain this teleconnection between AMO and ENSO? Is it that warmer Atlantic SSTs keep the MJO out of the Nino phases for longer?

[NotSparta]

Klotzbach believed we may have been ending the positive phase of the AMO after the 2013-2015 hurricane seasons. He has since begun to back off that assessment in his recent seasonal forecasts:

Four above-average seasons lends confidence that the AMO remains in a positive phase, although the far North Atlantic has generally been characterized by below-average sea surface temperatures (SSTs). One of the primary physical drivers for active versus inactive Atlantic basin hurricane seasons is the strength of the AMO (Gray et al. 1996, Goldenberg et al. 2001, Klotzbach and Gray 2008). A positive phase of the AMO (or strong phase of the THC) typically leads to 3-5 times more major Atlantic basin hurricane activity than does a negative phase. The typical period of the AMO is about 60 years, with the period length varying between as short as 40-50 years and if 70-80 years. This means that we typically have 25-35 years of above-average Atlantic basin major TC activity and similar length periods with considerably reduced amounts of major TC activity. Recently, we had three quiet Atlantic hurricane seasons in a row (e.g., 2013-2015) which led us to question whether we had moved out of the active era that began in 1995 (Klotzbach et al. 2015). However, the Atlantic has since had four active seasons in a row, which makes an assessment of whether we have moved out of the active Atlantic hurricane era quite murky.

Another clue that we're still in the positive phase of the AMO - shortened El Nino phases (like the one that is currently ending) are frequent, whereas a negative AMO phase we would see prolonged El Nino events.

Can you explain this teleconnection between AMO and ENSO? Is it that warmer Atlantic SSTs keep the MJO out of the Nino phases for longer?

Yeah, that's about it. A warmer tropical Atlantic discourages warm anomalies in the equatorial Pacific through the MJO

[cycloneye]

Accuweather made a new forecast going with higher numbers.

14-20
7-11
4-6

Excerpt:

Based on the newest forecasting models, AccuWeather forecasters have extended the upper range of hurricanes predicted for the Atlantic hurricane season. The hurricane team, led by Dan Kottlowski, the company’s top hurricane expert, is now predicting 14 to 20 tropical storms, with additions also to the number of storms that become hurricanes: seven to 11 this season.

Kottlowski also increased the number of major hurricanes – Category 3 or higher – that could develop this season to four to six. Kottlowski warned that four to six named tropical systems could make direct impacts on the U.S mainland, Puerto Rico and the Virgin Islands.

https://www.accuweather.com/en/hurrican ... ce=twitter

[toad strangler]

Accuweather made a new forecast going with higher numbers.

14-20
7-11
4-6

Excerpt:

Based on the newest forecasting models, AccuWeather forecasters have extended the upper range of hurricanes predicted for the Atlantic hurricane season. The hurricane team, led by Dan Kottlowski, the company’s top hurricane expert, is now predicting 14 to 20 tropical storms, with additions also to the number of storms that become hurricanes: seven to 11 this season.

Kottlowski also increased the number of major hurricanes – Category 3 or higher – that could develop this season to four to six. Kottlowski warned that four to six named tropical systems could make direct impacts on the U.S mainland, Puerto Rico and the Virgin Islands.

https://www.accuweather.com/en/hurrican ... ce=twitter

I usually don't use this much but I'm gonna here.

[FireRat]

It really is striking how all the expert outlooks are in consensus about 2020 being at least above average, many foresee hyperactivity.

Anyone remember.or know when was the last time all forecasting agencies were Gung Ho with their pre-season forecasts?

[hurricanes1234]

It really is striking how all the expert outlooks are in consensus about 2020 being at least above average, many foresee hyperactivity.

Anyone remember.or know when was the last time all forecasting agencies were Gung Ho with their pre-season forecasts?

2013?

Though that was an unusual case, the chances of us seeing another 2013 this year are very very low IMO.

[ScottNAtlanta]

It really is striking how all the expert outlooks are in consensus about 2020 being at least above average, many foresee hyperactivity.

Anyone remember.or know when was the last time all forecasting agencies were Gung Ho with their pre-season forecasts?

2013?

Though that was an unusual case, the chances of us seeing another 2013 this year are very very low IMO.

Actually, when JB initially put out WB's forecast he said that 2013 was one of his analogue years as one of his hedges on the forecast

[FireRat]

Wow, 2013, of all the years,
was not expecting that!

[AnnularCane]

I actually thought about mentioning 2013, but I must have gotten distracted.

[CrazyC83]

It really is striking how all the expert outlooks are in consensus about 2020 being at least above average, many foresee hyperactivity.

Anyone remember.or know when was the last time all forecasting agencies were Gung Ho with their pre-season forecasts?

2013?

Though that was an unusual case, the chances of us seeing another 2013 this year are very very low IMO.

That's why, even though I did raise my poll forecast, I didn't go as high as some of these agencies.