2018 Indicators: SST's / MSLP / Sal / Steering / Shear / Instability (Graphic updates at first post)

[galaxy401]

I'm sorry but I am not sold on there being an El Nino this year. Seems like that type of discussion happens every year and for the most part, it is over-exaggerated. I'm not saying that this Atlantic season will be active (other factors, mainly MDR) but the ENSO forecasts aren't my top factor at the moment.

[Alyono]

Monsoon trough in Caribbean in May is not exactly el niñoish

[HurricaneRyan]

For all we know, it could be a Modoki El Nino, which last happened in 2004 - and we all know how that happened.

Otherwise, I feel like it will be a neutral season similar to 1985.

[NotSparta]

For all we know, it could be a Modoki El Nino, which last happened in 2004 - and we all know how that happened.

Otherwise, I feel like it will be a neutral season similar to 1985.

A Modoki alone won't cause a hyperactive ATL - 2004 is over used here, imo. 2004 also had an extremely favorable base state to work with.

[Alyono]

For all we know, it could be a Modoki El Nino, which last happened in 2004 - and we all know how that happened.

Otherwise, I feel like it will be a neutral season similar to 1985.

2009 was more of a Modoki than a traditional. 2015 was kind of a hybrid of the two. Whole basin was warm in 2015, but the warmest was more out in the CPAC. Explains why the Atlantic could produce as many storms as it did in the MDR

[NDG]

All I know is that at least the western Caribbean & GOM are looking fairly favorable for development during the hurricane season based on current conditions, and most important low level divergence is well below average in the Caribbean that's not what happens during a developing El Nino.

[tolakram]

This looks familiar for the MDR.

[cycloneye]

Here is the May update of MSLP for ASO and wow,if this pans out MDR / Caribbean / GOM will shut down. But in 2017 it had this and we know and I endured it directly what occured.

[NotSparta]

This looks familiar for the MDR.

[img]https://i.imgur.com/4dKC6mq.png[img]

if the current SSTA appearence continues, convection may actually be suppressed, and waves could struggle. of course, things can change.

[stormlover2013]

its not even june yet lol

[Ntxw]

Wow. Pretty huge SST differences here. The SSTs in that subtropical region are now well above normal, and I can confirm that here in Bermuda. Compare that with well below temperatures right off of Africa and throughout the MDR.

http://i65.tinypic.com/2rfece9.png

In the mid and higher latitudes (not tropics) any blob of warm anomalies spatially, surrounded or bordered by cooler anomalies usually suggests a persistent feedback of big sprawling anomalous high pressure systems. In the Atlantic that creates the negative tripole if stretching eastward from North America to Bermuda, or as NotSparta mentioned above tends to suppress convection below due to stronger trades. It's taken several months of +NAO to develop this feature and to reverse will take a few months of -NAO.

[LarryWx]

Here is the May update of MSLP for ASO and wow,if this pans out MDR / Caribbean / GOM will shut down. But in 2017 it had this and we know and I endured it directly what occured.

In addition to 2017, tt would be really informative if we had access to or at least clear memories of past May Euro forecasts for ASO and then compared these to how the seasons went. Was 2017 reflective of a common Euro error/bias or was 2017 a rare error? Does anyone have access to or memories of 2016 and earlier May Euro forecasts for ASO?

[NDG]

Here is the May update of MSLP for ASO and wow,if this pans out MDR / Caribbean / GOM will shut down. But in 2017 it had this and we know and I endured it directly what occured.

In addition to 2017, tt would be really informative if we had access to or at least clear memories of past May Euro forecasts for ASO and then compared these to how the seasons went. Was 2017 reflective of a common Euro error/bias or was 2017 a rare error? Does anyone have access to or memories of 2016 and earlier May Euro forecasts for ASO?

I am sure those images are in archived threads in this forum, I may have the time later today to look for them.

[NotSparta]

Here is the May update of MSLP for ASO and wow,if this pans out MDR / Caribbean / GOM will shut down. But in 2017 it had this and we know and I endured it directly what occured.

In addition to 2017, tt would be really informative if we had access to or at least clear memories of past May Euro forecasts for ASO and then compared these to how the seasons went. Was 2017 reflective of a common Euro error/bias or was 2017 a rare error? Does anyone have access to or memories of 2016 and earlier May Euro forecasts for ASO?

It did similar in 2016, it has a warm bias for ENSO, making ATL pressures higher.

[Ntxw]

Here is the May update of MSLP for ASO and wow,if this pans out MDR / Caribbean / GOM will shut down. But in 2017 it had this and we know and I endured it directly what occured.

https://i.imgur.com/8yOUkw6.png

In addition to 2017, tt would be really informative if we had access to or at least clear memories of past May Euro forecasts for ASO and then compared these to how the seasons went. Was 2017 reflective of a common Euro error/bias or was 2017 a rare error? Does anyone have access to or memories of 2016 and earlier May Euro forecasts for ASO?

Larry You can find it in the link below. Goes back to 2008.

EUROSIP

[CyclonicFury]

I find it interesting that the Euro is showing near or even above normal pressures over the EPAC near Mexico. I wonder, if most of the Pacific activity is farther west, could that mean not as much shear over the Atlantic?

[Ntxw]

I find it interesting that the Euro is showing near or even above normal pressures over the EPAC near Mexico. I wonder, if most of the Pacific activity is farther west, could that mean not as much shear over the Atlantic?

That sounds about right. What the Euro long range ENS percentile shows is a strong CPAC season. Perhaps CPAC+WPAC crossovers

[tolakram]

Here was my May 3rd post in the 2017 Indicators thread. By May, and especially heading into the end of May, things are becoming more and more clear.

http://www.storm2k.org/phpbb2/viewtopic.php?p=2578868#p2578868

2017 was one of the few recent years that instability was even close to normal.

[Shell Mound]

Monsoon trough in Caribbean in May is not exactly el niñoish

Respectfully, I am not so sure that this is correct (though feel free to correct me). Looking back to 1950, I found several cases that apparently formed from Central-American monsoonal troughs in May or June during El Niño years: Cat-1 Abby (1968), Cat-1 Agnes (1972), Cat-1 Alberto (1982), and TS Alberto (2006). I looked up the pattern preceding the genesis of each of these systems, and in each case a Central-American monsoonal trough seemed to be present. Note the presence of anomalous westerly low-level winds over or near Central America, indicating the presence of a monsoonal circulation. I have decided to collect images of the patterns from ESRL and will post them here for individuals to examine and, if necessary, correct me (hopefully).

TS Alberto (2006):



Cat-1 Alberto (1982):



Cat-1 Agnes (1972):



Cat-1 Abby (1968):



Note that pre-Abby exhibits very weak westerly anomalies, but they do seem to be present just south of Central America, with some counterclockwise vectors present over Central America.

[Alyono]

Anny and especially One does not have westerly anomalies

Alberto did. No doubt about that. The tropical Atlantic still produced numerous storms that year. That niño wasn't very strong. The high latitudes only produced 2 though. Both in July