2020 Indicators: SST's / SAL / MSLP / Steering / Shear / Instability / Sat Images

[Cpv17]

When does SAL usually start to calm down? And when does shear in the Caribbean start to relax?

[cainjamin]

When does SAL usually start to calm down? And when does shear in the Caribbean start to relax?

SAL usually starts to abate by early August and reaches a minimum in the Fall. Shear in the Caribbean is usually around the minimum in August and September.

[MarioProtVI]

I think we can all agree CFS is a garbage model to hold onto for season predictions especially considering the Atlantic cranked out two systems in a SUPPRESSED phase of the MJO, one of which was almost a Cat 2 and the other a fairly strong MDR TS in July which you don’t see very often and usually indicates a good possibility of a hyperactive season. Let’s revisit this CFS thing on November 30 and see where we stand since 2020 clearly does not want to abide by the rules of climatology

[hurricaneCW]

CFS is garbage, expect a hyperactive season minus a possible lull sometime in August.

[Hammy]

I think we can all agree CFS is a garbage model to hold onto for season predictions especially considering the Atlantic cranked out two systems in a SUPPRESSED phase of the MJO, one of which was almost a Cat 2 and the other a fairly strong MDR TS in July which you don’t see very often and usually indicates a good possibility of a hyperactive season. Let’s revisit this CFS thing on November 30 and see where we stand since 2020 clearly does not want to abide by the rules of climatology

It's been accurate with trends but I'll agree that 2020 certainly isn't following the rules at all.

Hugging the CFS is a weird hill to die on.

Once again, I post it here every few days during July/August as part of the discussion on the indicators. It's the same model that's used to predict precipitation and such on monthly basis.

[TheStormExpert]

Anybody have any thoughts how/if the much warmer than normal pocket of water in the northern Pacific might impact potentially any steering in the Atlantic? One thought I have is maybe it causes a more progressive pattern as lows that track over the area might get stronger than normal which might cause perturbations in the jet stream across North America and Atlantic especially in the fall as mid-latitude lows traverse the Pacific. This progressive pattern might in turn impact the strength and and location of the Bermuda high causing it to be a bit weaker and more transient than normal?

https://i.postimg.cc/9FC3BQYd/ssta-daily-current.png

I’ve noticed the pattern has become more progressive in recent weeks. Likely has to do with that warm blob.

[USTropics]

Anybody have any thoughts how/if the much warmer than normal pocket of water in the northern Pacific might impact potentially any steering in the Atlantic? One thought I have is maybe it causes a more progressive pattern as lows that track over the area might get stronger than normal which might cause perturbations in the jet stream across North America and Atlantic especially in the fall as mid-latitude lows traverse the Pacific. This progressive pattern might in turn impact the strength and and location of the Bermuda high causing it to be a bit weaker and more transient than normal?

https://i.postimg.cc/9FC3BQYd/ssta-daily-current.png

I’ve noticed the pattern has become more progressive in recent weeks. Likely has to do with that warm blob.

There's still quite a bit of research into the warm "Blob" (or marine heatwave) that's situated off the coast of Alaska/Canada. It's more of a reflection of localized weather patterns, meaning the marine heatwave is a result of other atmospheric processes (i.e. a persistent ridge of high pressure relaxes winds and ocean surface mixing in that localized area, affecting the upper layers of the ocean). Looking further, a persistent band of high pressure extending to the Bering Sea/Alaska (as observed in 2014/2015) is a leading cause for the ridging and this persistent marine heatwave. Prolonged blocking events (which actually occur more frequently when the atmosphere is favoring La Nina in the North Pacific) and pattern shifts in the MJO are contributing factors as well.

TL;DR the prolonged marine heatwave likely has no effect (or research support) on steering patterns over North America/Atlantic basin, but is more of a reflection of larger atmospheric processes at play. Effects are contained locally (mainly marine life).

If you want to read more, check out this article - https://www.climate.gov/news-features/blogs/enso/seeing-red-across-north-pacific-ocean

[BYG Jacob]

I think we can all agree CFS is a garbage model to hold onto for season predictions especially considering the Atlantic cranked out two systems in a SUPPRESSED phase of the MJO, one of which was almost a Cat 2 and the other a fairly strong MDR TS in July which you don’t see very often and usually indicates a good possibility of a hyperactive season. Let’s revisit this CFS thing on November 30 and see where we stand since 2020 clearly does not want to abide by the rules of climatology

It's been accurate with trends but I'll agree that 2020 certainly isn't following the rules at all.

Hugging the CFS is a weird hill to die on.

Once again, I post it here every few days during July/August as part of the discussion on the indicators. It's the same model that's used to predict precipitation and such on monthly basis.

Predicting hurricane intensity and track is basically impossible 3 days out right now and you expect me to care about a models forecast for ASO?

[tolakram]

To all who are criticizing the CFS post.

This IS the place to discuss what the longer range models are showing. You don't have to like it, but the proper response would be to discuss how the CFS has done in the past and not criticize a poster for discussing it. Telling us not to believe the long range models in a thread about discussing long range trends and models is a bit awkward, to say the least.

[NDG]

To all who are criticizing the CFS post.

This IS the place to discuss what the longer range models are showing. You don't have to like it, but the proper response would be to discuss how the CFS has done in the past and not criticize a poster for discussing it. Telling us not to believe the long range models in a thread about discussing long range trends and models is a bit awkward, to say the least.

I agree, if we are going to disagree with a forecast and or model lets show our evidence.

[SconnieCane]

Amazing the things you learn on this forum. Before I started frequenting this forum I didn't even realize SAL was a thing. I basically took water temps and (lack of) shear as the main ingredients for TC development/intensification, moisture content of air didn't really come into it except for landfalling Gulf Coast hurricanes pulling in dry continental air and desiccating themselves (Ivan, Dennis, Katrina, Rita NOT Harvey and Michael). I guess I just assumed that air over the middle of the ocean had to be moist, I certainly didn't realize air and dust from Africa could blow all the way across the Atlantic.

[supercane4867]

Looks like CFS is forecasting 3-4 storms developing in August with mostly recurve tracks. The path in week 1 should be 92L.

Storm Count Forecast

RAW NUMBERS

PERIOD START END ATL ENP WNP NI SI AUS SP
-----------------------------------------------------------
Week 1 20200726 20200801 1.1 0.2 0.1 0.3 0.0 0.0 0.2
Week 2 20200802 20200808 0.3 0.9 0.9 0.3 0.2 0.0 0.1
Week 3 20200809 20200815 0.7 2.4 1.6 0.7 0.5 0.0 0.1
Week 4 20200816 20200822 1.8 3.1 2.5 0.8 0.4 0.0 0.1
Week 5 20200823 20200829 1.3 1.7 1.4 0.7 0.2 0.0 0.0
Week 6 20200830 20200905 0.0 0.0 0.0 0.0 0.0 0.0 0.0
30 Day 20200726 20200824 3.4 4.3 3.5 1.4 0.5 0.0 0.3


BIAS CORRECTED

PERIOD START END ATL ENP WNP NI SI AUS SP
-----------------------------------------------------------
Week 1 20200726 20200801 0.7 0.0 0.0 0.0 0.0 0.0 0.0
Week 2 20200802 20200808 0.0 0.3 0.7 0.0 0.0 0.0 0.0
Week 3 20200809 20200815 0.1 2.0 0.8 0.0 0.2 0.0 0.0
Week 4 20200816 20200822 1.2 2.3 2.0 0.0 0.0 0.0 0.0
Week 5 20200823 20200829 0.9 1.5 1.0 0.0 0.0 0.0 0.0
Week 6 20200830 20200905 0.5 0.0 0.0 0.0 0.0 0.0 0.0
30 Day 20200726 20200824 3.0 3.6 2.8 0.0 0.0 0.0 0.0

[St0rmTh0r]

Looks like CFS is forecasting 3-4 storms developing in August with mostly recurve tracks. The path in week 1 should be 92L.

Storm Count Forecast

RAW NUMBERS

PERIOD START END ATL ENP WNP NI SI AUS SP
-----------------------------------------------------------
Week 1 20200726 20200801 1.1 0.2 0.1 0.3 0.0 0.0 0.2
Week 2 20200802 20200808 0.3 0.9 0.9 0.3 0.2 0.0 0.1
Week 3 20200809 20200815 0.7 2.4 1.6 0.7 0.5 0.0 0.1
Week 4 20200816 20200822 1.8 3.1 2.5 0.8 0.4 0.0 0.1
Week 5 20200823 20200829 1.3 1.7 1.4 0.7 0.2 0.0 0.0
Week 6 20200830 20200905 0.0 0.0 0.0 0.0 0.0 0.0 0.0
30 Day 20200726 20200824 3.4 4.3 3.5 1.4 0.5 0.0 0.3


BIAS CORRECTED

PERIOD START END ATL ENP WNP NI SI AUS SP
-----------------------------------------------------------
Week 1 20200726 20200801 0.7 0.0 0.0 0.0 0.0 0.0 0.0
Week 2 20200802 20200808 0.0 0.3 0.7 0.0 0.0 0.0 0.0
Week 3 20200809 20200815 0.1 2.0 0.8 0.0 0.2 0.0 0.0
Week 4 20200816 20200822 1.2 2.3 2.0 0.0 0.0 0.0 0.0
Week 5 20200823 20200829 0.9 1.5 1.0 0.0 0.0 0.0 0.0
Week 6 20200830 20200905 0.5 0.0 0.0 0.0 0.0 0.0 0.0
30 Day 20200726 20200824 3.0 3.6 2.8 0.0 0.0 0.0 0.0

https://i.imgur.com/Z0fxlo1.gif

So how many did it predict for July?

[supercane4867]

So how many did it predict for July?

This is from a month ago on June 26. It predicted a mere 1 storm for the next 30 days.

Storm Count Forecast

RAW NUMBERS

PERIOD START END ATL ENP WNP NI SI AUS SP
-----------------------------------------------------------
Week 1 20200626 20200702 0.1 2.0 0.7 0.2 0.0 0.0 0.0
Week 2 20200703 20200709 0.4 2.3 0.9 0.9 0.0 0.1 0.0
Week 3 20200710 20200716 0.9 2.5 0.6 1.2 0.4 0.0 0.1
Week 4 20200717 20200723 0.9 2.1 0.6 0.9 0.8 0.0 0.1
Week 5 20200724 20200730 0.5 0.7 0.3 0.4 0.8 0.0 0.1
Week 6 20200731 20200806 0.0 0.0 0.0 0.0 0.0 0.0 0.0
30 Day 20200626 20200725 1.4 4.5 1.8 1.7 0.8 0.1 0.1


BIAS CORRECTED

PERIOD START END ATL ENP WNP NI SI AUS SP
-----------------------------------------------------------
Week 1 20200626 20200702 0.0 1.1 0.2 0.0 0.0 0.0 0.0
Week 2 20200703 20200709 0.0 0.7 0.3 0.3 0.0 0.0 0.0
Week 3 20200710 20200716 0.3 1.4 0.3 0.5 0.1 0.0 0.0
Week 4 20200717 20200723 0.4 1.3 0.2 0.2 0.3 0.0 0.0
Week 5 20200724 20200730 0.0 0.1 0.0 0.0 0.3 0.0 0.0
Week 6 20200731 20200806 0.0 0.0 0.0 0.0 0.0 0.0 0.0
30 Day 20200626 20200725 0.1 2.9 1.1 0.3 0.2 0.0 0.0

[supercane4867]

Also you can notice a high bias for EPAC on those NCEP models(which includes the CFS). They have modeled many phantom storms over there that didn't pan out.

[StruThiO]

Surface pressures have been extremely low in the MDR lately:







note the monsoon trof extending along 13N in July

[gatorcane]

Anybody have any thoughts how/if the much warmer than normal pocket of water in the northern Pacific might impact potentially any steering in the Atlantic? One thought I have is maybe it causes a more progressive pattern as lows that track over the area might get stronger than normal which might cause perturbations in the jet stream across North America and Atlantic especially in the fall as mid-latitude lows traverse the Pacific. This progressive pattern might in turn impact the strength and and location of the Bermuda high causing it to be a bit weaker and more transient than normal?

https://i.postimg.cc/9FC3BQYd/ssta-daily-current.png

I’ve noticed the pattern has become more progressive in recent weeks. Likely has to do with that warm blob.

There's still quite a bit of research into the warm "Blob" (or marine heatwave) that's situated off the coast of Alaska/Canada. It's more of a reflection of localized weather patterns, meaning the marine heatwave is a result of other atmospheric processes (i.e. a persistent ridge of high pressure relaxes winds and ocean surface mixing in that localized area, affecting the upper layers of the ocean). Looking further, a persistent band of high pressure extending to the Bering Sea/Alaska (as observed in 2014/2015) is a leading cause for the ridging and this persistent marine heatwave. Prolonged blocking events (which actually occur more frequently when the atmosphere is favoring La Nina in the North Pacific) and pattern shifts in the MJO are contributing factors as well.

TL;DR the prolonged marine heatwave likely has no effect (or research support) on steering patterns over North America/Atlantic basin, but is more of a reflection of larger atmospheric processes at play. Effects are contained locally (mainly marine life).

If you want to read more, check out this article - https://www.climate.gov/news-features/blogs/enso/seeing-red-across-north-pacific-ocean

Thanks this looks like a good read!

[St0rmTh0r]

Looks like CFS is forecasting 3-4 storms developing in August with mostly recurve tracks. The path in week 1 should be 92L.

Storm Count Forecast

RAW NUMBERS

PERIOD START END ATL ENP WNP NI SI AUS SP
-----------------------------------------------------------
Week 1 20200726 20200801 1.1 0.2 0.1 0.3 0.0 0.0 0.2
Week 2 20200802 20200808 0.3 0.9 0.9 0.3 0.2 0.0 0.1
Week 3 20200809 20200815 0.7 2.4 1.6 0.7 0.5 0.0 0.1
Week 4 20200816 20200822 1.8 3.1 2.5 0.8 0.4 0.0 0.1
Week 5 20200823 20200829 1.3 1.7 1.4 0.7 0.2 0.0 0.0
Week 6 20200830 20200905 0.0 0.0 0.0 0.0 0.0 0.0 0.0
30 Day 20200726 20200824 3.4 4.3 3.5 1.4 0.5 0.0 0.3


BIAS CORRECTED

PERIOD START END ATL ENP WNP NI SI AUS SP
-----------------------------------------------------------
Week 1 20200726 20200801 0.7 0.0 0.0 0.0 0.0 0.0 0.0
Week 2 20200802 20200808 0.0 0.3 0.7 0.0 0.0 0.0 0.0
Week 3 20200809 20200815 0.1 2.0 0.8 0.0 0.2 0.0 0.0
Week 4 20200816 20200822 1.2 2.3 2.0 0.0 0.0 0.0 0.0
Week 5 20200823 20200829 0.9 1.5 1.0 0.0 0.0 0.0 0.0
Week 6 20200830 20200905 0.5 0.0 0.0 0.0 0.0 0.0 0.0
30 Day 20200726 20200824 3.0 3.6 2.8 0.0 0.0 0.0 0.0

https://i.imgur.com/Z0fxlo1.gif

So how many did it predict for July?

Epic fail is an understatement.

[St0rmTh0r]

Surface pressures have been extremely low in the MDR lately:

https://i.imgur.com/DE7ZsXV.png

https://i.imgur.com/zePCMR2.png

https://i.imgur.com/vVPdlxv.png

note the monsoon trof extending along 13N in July

Well no wonder there has been early CV activity. This is a very bad sign for the peak of hurricane season. I see another strong wave behind 92L so this is getting serious. I think August and September is gonna break records. I've never seen signs this strong for hyperactivity in a season. 5 storms in July I made a prediction of 10 storms forming in the August poll. I'm sticking to that. September could see even more activity

[St0rmTh0r]

To all who are criticizing the CFS post.

This IS the place to discuss what the longer range models are showing. You don't have to like it, but the proper response would be to discuss how the CFS has done in the past and not criticize a poster for discussing it. Telling us not to believe the long range models in a thread about discussing long range trends and models is a bit awkward, to say the least.

I agree, if we are going to disagree with a forecast and or model lets show our evidence.

Well the fact that 4 going on 5 storms have formed this month when the CFS predicted 1 is all the evidence we need.