MSLP forecast to be low during peak of 2010 Atlantic season

[RL3AO]

This was an update for Dr. Gray's Forecast. He upped his numbers to 13/7/3 ( )

Maybe he meant by September?

[cycloneye]

No change from the March update.It continues to show very low pressures in the MDR and Caribbean.

ECMWF April MSLP for July,August and September update

[hurricanetrack]

Luis- thanks for staying on top of this. Very cool info to have. I love it that we can all see the pieces to the puzzle.

[cycloneye]

Also the ECMWF forecast of precipitation looks scary for the Caribbean.

ECMWF Precipitation April update for July,August and September

[Macrocane]

It seems that the temperature in Central America will be below normal and that's nice but we could have plenty of rain. 2008 and 2005 were very rainy years in Central America but 2008 had less disasters than 2005 so I hope this year will be more like 2008 than 2005.

[cycloneye]

Holy smokes!! Here is the updated ECMWF for ASO (August,September & October) forecast of MSLP yes,for the peak of the season and is really scary how the Atlantic,Caribbean and GOM look with the blue color that means below average pressures.

ECMWF ASO MSLP forecast

[KWT]

Yeah the ECM still suggestive of a very active season with below normal pressures, its very impressive to see just how much of the tropical Atlantic is below normal according to the model!

[wxman57]

Another point is that the new 3-month forecast for July-September is for even lower pressures than the 4-month forecast for the same period issued in March. The trend is definitely for lower and lower pressure in the Tropics.

[KWT]

Its really impressive Wxman57, as you said the ECM is now going for average pressure 1-2mbs lower over the three months of ASO, which is quite significant it has to be said over that length of time in the tropics...

[WeatherEmperor]

That map shows below average sea level pressure forecasts. Does that also mean that the bermuda high will be weak as well? Is the bermuda high determined by the sea level pressure or the mid/level ridge?

[Blown Away]

Does low pressures mean the Bermuda/Azores high will be weak this season. Maybe will have more homegrown system threats compared to CV system threats?

[KWT]

Whilst that can be the case it doesn't always work like that, the global patterns at the moment actually are quite suggestive of a strong Azores High developing, and whilst you can't see it on the pressure maps on the ECM forecast, you can see below average precip expected for the Canary Islands/Azores region which you'd expect with a stronger Azores High.

Bermuda High however is expected to be weaker so we could possibly see tracks like 1995 with the E.Caribbean at more threat?

Also worth noting the ECM expects a very high risk (70%+) that this is in the top 20% of lowest pressures in the tropics over ASO.

[wxman57]

The ECMWF prediction does indicate a weaker Azores-Bermuda High this season. This would go along with a projection of a negative NAO (deeper trof western Atlantic). Negative NAO means the pressure center is shifted eastward closer to the Azores than Bermuda. I don't separate the high into two centers. Sort of what KWT is saying (stronger AZORES high). But the reason for the increased rainfall projection for the Caribbean is not because of a stronger Azores-Bermuda High, it's because the high is weaker across the Tropical Atlantic. Lower pressure means more rising air in the tropical Atlantic. In addition, weaker easterly trades would pull less dry air out of Africa.

Last year, the Bermuda High was significantly stronger, as had been forecast correctly by the ECMWF. This resulted in tremendous low-level easterly winds, up to 50-60 kts at times at 5000 ft in the Caribbean. The high low-level shear and substantial amount of dry air coming off Africa in 2009 was a major factor in the lack of activity.

[cycloneye]

The ECMWF prediction does indicate a weaker Azores-Bermuda High this season. This would go along with a projection of a negative NAO (deeper trof western Atlantic). The reason for the increased rainfall projection for the Caribbean is not because of a stronger high, it's because the high is weaker. Lower pressure means more rising air in the tropical Atlantic. In addition, weaker easterly trades would pull less dry air out of Africa.

Last year, the Bermuda High was significantly stronger, as had been forecast correctly by the ECMWF. This resulted in tremendous low-level easterly winds, up to 50-60 kts at times at 5000 ft in the Caribbean. The high low-level shear and substantial amount of dry air coming off Africa in 2009 was a major factor in the lack of activity.

57,also weaker trade winds,less sal outbreaks.

[Blown Away]

The ECMWF prediction does indicate a weaker Azores-Bermuda High this season. This would go along with a projection of a negative NAO (deeper trof western Atlantic). Negative NAO means the pressure center is shifted eastward closer to the Azores than Bermuda. Sort of what KWT is saying (stronger AZORES high). But the reason for the increased rainfall projection for the Caribbean is not because of a stronger Azores-Bermuda High, it's because the high is weaker across the Tropical Atlantic. Lower pressure means more rising air in the tropical Atlantic. In addition, weaker easterly trades would pull less dry air out of Africa.

Last year, the Bermuda High was significantly stronger, as had been forecast correctly by the ECMWF. This resulted in tremendous low-level easterly winds, up to 50-60 kts at times at 5000 ft in the Caribbean. The high low-level shear and substantial amount of dry air coming off Africa in 2009 was a major factor in the lack of activity.

So how does JB come up w/ so many landfalls w/ a weaker Azores-Bermuda high?

[wxman57]

So how does JB come up w/ so many landfalls w/ a weaker Azores-Bermuda high?

A weaker high could allow for a number of recurving storms well east of the U.S. However, not all storms will develop in the far eastern Atlantic. With the Caribbean also quite favorable for development, systems developing farther west would mean an increased risk to the U.S.

[hurricanetrack]

I just think of 2005 as a great example of what little difference it really makes in the strength or weakness of the Bermuda/Azores high. Why? In THAT year, all of the big time landfalling U.S. hurricanes formed far enough west so that it was too late for them to curve east of the mainland. If there are enough of them, some will get passed the goalie. That is my concern anyway. And look at it this way- out of 28 named storms that year, how many hit the U.S.? Most did not- but the ones that did (most of them) are now part of hurricane history.

[wxman57]

1995 is one of our analog years, too. Remember that conveyor belt of developing storms? We had 4 hurricanes going at one time. Most recurved near the eastern Caribbean that year.

[hurricanetrack]

Totally understand. My point is that you can both live and die by the subtropical ridge. If we get enough activity to form west of 50 W, then it could be a long and painful season for many. We are about to find out - that is for sure.

[Derek Ortt]

looks like the el nino dance didn't work

time for a SAL dance