Seasonal Indicators (Beyond Day 16): Instability / SST's / MSLP / Steering / Sal

[TheStormExpert]

SST's continue to get warmer in the GoM, now warmer than the East Pacific.

 https://twitter.com/tropicaltidbits/status/751402598087917568

[gatorcane]

This is some SAL surge in progress, though SAL is usually highest across the Atlantic this month.

NWS Miami discussion today mentions the words "mid-level dry air" multiple times as far as what continues to basically squash any rain chances across the already dry and below normal rainy season rainfall across SE Florida. This is the same airmass which looks to be dominating most of the Atlantic at the moment.

So until things change drastically, I don't see any MDR development anytime soon.

The posts in this forum are NOT official forecasts and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or STORM2K. For official information, please refer to products from the NHC and NWS.

[tarheelprogrammer]

This is some SAL surge in progress, though SAL is usually highest across the Atlantic this month.

NWS Miami discussion today mentions the words "mid-level dry air" multiple times as far as what continues to basically squash any rain chances across the already dry and below normal rainy season rainfall across SE Florida. This is the same airmass which looks to be dominating most of the Atlantic at the moment.

So until things change drastically, I don't see any MDR development anytime soon.

http://i.imgur.com/GLHwWQJ.jpg

The posts in this forum are NOT official forecasts and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or STORM2K. For official information, please refer to products from the NHC and NWS.

Possibly giving me credence to my thoughts of lowering my numbers for this hurricane season. maybe.

[WPBWeather]

This is some SAL surge in progress, though SAL is usually highest across the Atlantic this month.

NWS Miami discussion today mentions the words "mid-level dry air" multiple times as far as what continues to basically squash any rain chances across the already dry and below normal rainy season rainfall across SE Florida. This is the same airmass which looks to be dominating most of the Atlantic at the moment.

So until things change drastically, I don't see any MDR development anytime soon.

http://i.imgur.com/GLHwWQJ.jpg

The posts in this forum are NOT official forecasts and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or STORM2K. For official information, please refer to products from the NHC and NWS.

SAL is always around this time of year. It is not as bad as last year though. Not really any indicator of future activity. Larry Cosgrove among others has said it is raining more in Africa now, less SAL on the way.

[TheStormExpert]

The same Larry Cosgrove who was forecasting a hyperactive season last year due to a strengthening La Niña when everyone else was screaming record strong El Niño.

[wxman57]

New ECMWF seasonal forecasts (July) are out (for paid users). It's still going with 90% normal ACE August-November, and 11 additional named storms, 7 of those hurricanes. Predicting near normal precip levels all across the deep tropics, as opposed to the bone-dry air it predicted last season. Little change to the Nino 3.4 prediction (neutral to weak La Nina).

[Hammy]

New ECMWF seasonal forecasts (July) are out (for paid users). It's still going with 90% normal ACE August-November, and 11 additional named storms, 7 of those hurricanes. Predicting near normal precip levels all across the deep tropics, as opposed to the bone-dry air it predicted last season. Little change to the Nino 3.4 prediction (neutral to weak La Nina).

Is the 90% a probability of normal, or percentage of normal? And is the track record fairly good for the seasonal forecasts?

[WPBWeather]

:uarrow: The same Larry Cosgrove who was forecasting a hyperactive season last year due to a strengthening La Niña when everyone else was screaming record strong El Niño.

No it is not. And hold off the snark of Pro Mets please.

[Yellow Evan]

:uarrow: The same Larry Cosgrove who was forecasting a hyperactive season last year due to a strengthening La Niña when everyone else was screaming record strong El Niño.

No it is not. And hold off the snark of Pro Mets please.

https://groups.google.com/forum/?hl=en# ... LWSWj0OV78

Last year Cosgrove called for 15/9/6 and a La Nina in March. A huge mistake, given the AMO and super El Nino (although the warmest watters were center in the east).

[WPBWeather]

:uarrow: The same Larry Cosgrove who was forecasting a hyperactive season last year due to a strengthening La Niña when everyone else was screaming record strong El Niño.

No it is not. And hold off the snark of Pro Mets please.

https://groups.google.com/forum/?hl=en# ... LWSWj0OV78

Last year Cosgrove called for 15/9/6 and a La Nina in March. A huge mistake, given the AMO and super El Nino (although the warmest watters were center in the east).

I believe he moderated it a bit later on, as other well known Pro Mets did. As to the rain comment I made, that is not in doubt to those who care to look.

[Hammy]

No it is not. And hold off the snark of Pro Mets please.

https://groups.google.com/forum/?hl=en# ... LWSWj0OV78

Last year Cosgrove called for 15/9/6 and a La Nina in March. A huge mistake, given the AMO and super El Nino (although the warmest watters were center in the east).

I believe he moderated it a bit later on, as other well known Pro Mets did. As to the rain comment I made, that is not in doubt to those who care to look.

It doesn't really work comparing March and July forecasts either--more is far less doubt about what will happen now than there would be in March.

[ScottNAtlanta]

I think the GOM warming is also associated with the Loop current eddy that recently detached

also you can see this on the SST frames

[BigA]

This is some SAL surge in progress, though SAL is usually highest across the Atlantic this month.

NWS Miami discussion today mentions the words "mid-level dry air" multiple times as far as what continues to basically squash any rain chances across the already dry and below normal rainy season rainfall across SE Florida. This is the same airmass which looks to be dominating most of the Atlantic at the moment.

So until things change drastically, I don't see any MDR development anytime soon.

http://i.imgur.com/GLHwWQJ.jpg

The posts in this forum are NOT official forecasts and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or STORM2K. For official information, please refer to products from the NHC and NWS.

SAL is always around this time of year. It is not as bad as last year though. Not really any indicator of future activity. Larry Cosgrove among others has said it is raining more in Africa now, less SAL on the way.

African precipitation in June was above normal in the Sahel.

Climate models generally forecast above-normal rain in the Sahel during the next month. Here is the week four forecast from the CFSv2, for example.

Greater rain should promote more vegetation, but the extent to which this reduces the SAL is uncertain. Previous research has indicated that summer precipitation in the Sahel may have a greater effect on SAL the following year. However, there is solid evidence for a correlation between summertime Sahel precipitation and the number of Atlantic major hurricanes (e.g. Landsea and Gray 1992).

[SFLcane]

New ECMWF seasonal forecasts (July) are out (for paid users). It's still going with 90% normal ACE August-November, and 11 additional named storms, 7 of those hurricanes. Predicting near normal precip levels all across the deep tropics, as opposed to the bone-dry air it predicted last season. Little change to the Nino 3.4 prediction (neutral to weak La Nina).

Thx 57.

[WeatherEmperor]

I see near normal precipitation across the tropics but how about pressures? Higher or lower pressures??

New ECMWF seasonal forecasts (July) are out (for paid users). It's still going with 90% normal ACE August-November, and 11 additional named storms, 7 of those hurricanes. Predicting near normal precip levels all across the deep tropics, as opposed to the bone-dry air it predicted last season. Little change to the Nino 3.4 prediction (neutral to weak La Nina).

[tarheelprogrammer]

What is causing the waves to die right now? Shear doesn't seem too high and the SAL is thick but waves are still making it out of it. May be a dumb question but it has me scratching my head as I am not a MET.

[Hammy]

What is causing the waves to die right now? Shear doesn't seem too high and the SAL is thick but waves are still making it out of it. May be a dumb question but it has me scratching my head as I am not a MET.

Combination of low moisture and the ITCZ's position--as the SAL goes further west and out, and the ITCZ moves north, the waves will likely start strengthening and become separate entities increasingly as they move off.

[tarheelprogrammer]

What is causing the waves to die right now? Shear doesn't seem too high and the SAL is thick but waves are still making it out of it. May be a dumb question but it has me scratching my head as I am not a MET.

Combination of low moisture and the ITCZ's position--as the SAL goes further west and out, and the ITCZ moves north, the waves will likely start strengthening and become separate entities increasingly as they move off.

When does the ITCZ usually move north?

[Hammy]

What is causing the waves to die right now? Shear doesn't seem too high and the SAL is thick but waves are still making it out of it. May be a dumb question but it has me scratching my head as I am not a MET.

Combination of low moisture and the ITCZ's position--as the SAL goes further west and out, and the ITCZ moves north, the waves will likely start strengthening and become separate entities increasingly as they move off.

When does the ITCZ usually move north?

Usually seems to gradually do so during July and into early August, and increasingly becomes less of a continuous band and breaks into individual waves.

[tarheelprogrammer]

Combination of low moisture and the ITCZ's position--as the SAL goes further west and out, and the ITCZ moves north, the waves will likely start strengthening and become separate entities increasingly as they move off.

When does the ITCZ usually move north?

Usually seems to gradually do so during July and into early August, and increasingly becomes less of a continuous band and breaks into individual waves.

Thanks Hammy your insight is greatly appreciated.