1997 vs 2009

[boca]

I look back at how many storms we had back in 1997 which was eight.That was when we had that strong El Nino develop in 1997/98. In 2009 so far we have 3 storms that ironically developed last weekend within 72 hrs we had 3. I think the El Nino will be a weak one but so far we have 5 storms to tie 1997 and 6 to beat that year. We are entering the dry MJO phase and then our next shot is in mid Sept timeframe. Lets see what happens it should be interesting to see if we can beat the number from 1997.

http://www.wunderground.com/hurricane/at1997.asp

[Sanibel]

You have to figure that the MJO has shown itself to be the main trigger in this season's prevailing negative conditions. So if it comes at the climatological peak it should have some surprises in store for us as far as impressive storms.


If you look at your 1997 track map nothing went west that year. All storms tracked east.

[boca]

I think in mid Sept things will ramp up with the trigger of the MJO. Something also can form in the NGOM like models are indicating by next weekend.I think we have a way to go before we beat 1997.I thought by now other than Bill the ITCZ would by popping more by now.After Bill I think we might be inactive for a week or two due to the dry MJO. So much for the crystal ball theory its all guessing on what will transpire this year.

[KWT]

The MJO isn't going to stop storms forming, esp during late August-late September. Its the difference between 5-8 storms in September and 3-4 storms in most seasons.

Also when the MJO phase does come more favorable, could well see once again 2-3 storms in the space of a week.

The dry MJO isn't even close to being the be all and end all, sure it may reduce activity somewhat but its certainly not going to stop it, don't expect to see 2-3 weeks of utterly nothing, maybe just 1-2 storms rather then the full works.

Also don't bet the Mid September MJO ramp will be that impressive, thats typically when the El Nino really shows its hand, not common to get more then 2 storms after the 20th in El nino's, even in weak el Ninos.

Also finally, in El Nino's you don't often get that many Cape Verde hurricanes, you need to look closer to home.

All in all, should still see 2 storms between now and say the 10th of September, then prehaps a busier 10 days (another 2-3 storms) before El Nino comes down and shuts it all down by late September.

[Ptarmigan]

1997 had an earlier start and had four storms by July. If it wasn't for that strong El Nino of 1997-8, the season would of been more active.

[KWT]

As Derek has said before, the reason why it had so many storms early was because of the El Nino, dug down plenty of troughs and fronts which developed storms on them, then that dried up and we only got 3 storms after that.

[Macrocane]

The MJO this season has been rather weak and I don't think it will have a great influence for the rest of the season. I think the next period of activity will be on the first week of September as we reach the peak of the season. IMO the rest of 2009 ATL hurricane season will be more active than the same period on 1997,

[cycloneye]

A big difference is that El Nino is much much weak than in 1997 when it was a very strong one.(See ENSO Updates thread)

[KWT]

Yeah cycloneye they aren't even in the same league to be honest, 1997 was well on its way to being a strong event already at this point, meanwhile this event hasn't really gone beyond 0.9C yet.

[HurricaneRobert]

Plus the west Pacific had 10 category 5 storms that year. This year: 0.

[jinftl]

Are we comparing storm count for those 2 seasons or comparing el ninos?

In terms of strength of el nino, 1997 is several standard deviations stronger in terms of magnitude compared to the current el nino. Based on 3-month ONI SST anomalies, 2009 is running neck in neck with the 2004 el nino, slightly weaker than the 2002 el nino, and light years from 1997's.

[boca]

So far I'm pretty much writing off this season off at six named storms. In 1997 when we had that strong El Nino we had eight. We can still get two more storms but the way its looking out there I doubt it. When I started this thread I thought we'd easily would of had ten systems by now.I'm surprised, but this season is more lame then in 1997 as far as someone who likes to track these storms.

[Emmett_Brown]

Given that the current El Nino is weak, If we end up with a lower ace than '97, then we have to assume that there is another negative factor other than El Nino at work causing all the shear (namely upper and mid level lows along with sinking air, but can those factors be forecasted before a season starts?)

[Ptarmigan]

Given that the current El Nino is weak, If we end up with a lower ace than '97, then we have to assume that there is another negative factor other than El Nino at work causing all the shear (namely upper and mid level lows along with sinking air, but can those factors be forecasted before a season starts?)

I wonder about that too. North Atlantic Oscillation, Arctic Oscillation, and Pacific Decadal Oscillation are also a factor besides El Nino. 1977 was inactive for Atlantic and all the basins. 1977 had a weak El Nino that time.

[Derek Ortt]

Given that the current El Nino is weak, If we end up with a lower ace than '97, then we have to assume that there is another negative factor other than El Nino at work causing all the shear (namely upper and mid level lows along with sinking air, but can those factors be forecasted before a season starts?)

or, have we flipped back to a quiet phase. Something to think about

[Ptarmigan]

or, have we flipped back to a quiet phase. Something to think about

Possible. I wonder how they determine an active phase and less active phase.
1900-1925-Less Active
1926-1969-More Active
1970-1994-Less Active
1995-?-More Active

[cycloneye]

However,only one inactive year wont tell us anything about if the active phase is over.If we see a string of years like 2009,then its over for the active phase.

[weatherwindow]

However,only one inactive year wont tell us anything about if the active phase is over.If we see a string of years like 2009,then its over for the active phase.

altho nothing but nothing is absolute in meteorology, the warm/cool phases of the atc cycle have tended to average approx 30-35 years in length. of course, we are always at the mercy of the limited number of cycles in the observed record(roughly two centuries). the individual seasons within the warm and cool phases have exhibited a great deal of variability. tropical activity is determined by a variety of factors in addition to the cyclical variation in ssts inherent in the atc fluxes. examination of the decade of the 1940's might be useful to illustrate this variability during the height of a previous warm phase. given everything cited above and limitations of the science, i still feel that the current warm phase could extend well into the 2020's........rich

[Cyclenall]

What makes the inactivity of 2009 even more impressive is how the numbers are lower than 1997 (TS's) yet this is a weak El Nino and not a strong one.

or, have we flipped back to a quiet phase. Something to think about

In ten years from now I will think about it.

[MGC]

I'm pretty sure El Nino is the cause of this season's low numbers. Classic El Nino with plenty of shear......MGC