CSU's Klotzbach Addresses Lack of Hurricane Activity

[lonelymike]

Now about that bet.....

[Steve]

>>Now about that bet.....

I'm down (if necessary). I threw out the gauntlet and I stick to my word. But I REALLY don't think very many people on here believe the season will end with the I storm. I could see getting to 13 or 14 pretty easily (remember, I didn't come out with any numbers this year). Clearly we won't be in the K's (or was it L) before the end of the month like we were in August of '05, but I'm comfortably sure enough that we'll get there before the season is up to place the bet.

To be blunt about the topic though, early season #'s predictions all seemed a little high to me. I can get with 13 or 14, yeah, that's going to be a busy season. Any more than that and we're approaching rare territory (in an admittedly short timespan of measurement relative to how long there have been hurricanes). One note of caution though. I don't think I'll ever forget Bastardi in early 2005. He used to do these landfall intensity forecasts and may still. I don't know because I refuse to support his weather corporation (to me he brings enough value and insight that I probably would pay for his service if he was independent). Anyway, these forecasts (you'll probably remember them) used to quantify a numerical impact on specific landfall zones. That is, a TD (or stronger storm that brings TD conditions into an adjacent landfall zone) was scored like .5 or 1. A TS was double that, either 1 or 2) and so on. It went all the way to either 32 or 64 for a Cat 5 impact on a zone. And he'd add up his analog and expected impacts and give a score for the season which was the total of the zones. In his revised forecast in late July or early August, he had a ridiculous number score which was significantly greater than any of the previous years he was developing that model. Particularly high was his implication for the Northern Gulf Coast (including the LA Zone which was all of LA and the MS/AL/NWF Zone). The numbers were like in the teens or twenties so you had to figure some combination of pretty strong storms or maybe a Cat 3 impact if he was right. His updated overall number was something off the charts. And he said he wasn't going to release the real number because the bosses would not let him it was so outrageous. And yeah, after Rita and whatever other impacts we had (I was completely out of the loop after that), his ridiculous number to start with was low.

Who knows?

[ConvergenceZone]

Steve, I can agree with your 13 or 14. It's just the 16+ that many people are saying that I don't buy...
I could be wrong, sure, but I just don't think I will be......

[Steve]

I hear you. I wouldn't be shocked if we got to 15 or 16 because most of the seasonal forecasts were a little higher than that. But I highly doubt we see 18. Admittedly, there is the possibility of 2010 extending a little later than the average season. But it's not like we're up to F or G already where you legitimately wonder if we have a shot at the Greek Alphabet. I just can't see it.

[hurricaneCW]

The eastern Atlantic is actually surprisingly favorable for development. The shear is very light and the SAL is nearly nonexistent, but it takes a while for a disturbance to get together, so once it starts to develop it moves into the central Atlantic near the TUTT and it falls apart.

[weatherwindow]

a final thought..the forecast verification papers from the various agencies(csu, noaa, tsr etc etc) may provide a more intriguing read than the tropical cyclone prelims:)....rich...ps, just an aside...following this and other trop sites over the years..just wanted to express the high opinion in which i hold this group, both quantity and quality...intelligent, on topic(sort of), and well lead(props here, mods)....keep it up

[KWT]

The eastern Atlantic is actually surprisingly favorable for development. The shear is very light and the SAL is nearly nonexistent, but it takes a while for a disturbance to get together, so once it starts to develop it moves into the central Atlantic near the TUTT and it falls apart.

Its been the trend thus far thats for sure. What we really want to see if the TUTT weakening and the models are certainly hinting at that...the TUTT normally is at its strongest at this point and then usually weakens...the thing that made 2007 unusual is the TUTT held right into October...I'd be surprised if that occured this time.

The upper high should strengthen as well, the ECM is finally showing this strengthening as well wghich it hasn't before and thus systems wion't lift right into the TUTT too quickly anyway and by then it maybe a much weaker feature anyway.

[abajan]

We may have 121 days, but those last 45 days are generally storm free and unfavorable for additional development. Since we've been going with climatology so far, we really only have about 30-45 days to get all of those storms that were forecast. We also have to get several hurricanes and major hurricanes to reach expectations. The period of August 15-September 30 is our best bet. The models don't show much in the way of development extending all the way to August 20-25th.

This is a La Niña season (a pretty strong La Niña at that). Translation: Likely a late starting, long lasting season. I actually expect to see an out of season system this year in December. Not only that but some of the worst hurricanes in the history of the Atlantic have occurred in October. For instance, the Great Hurricane of 1780. And who can forget the infamous Mitch 1998 whose peak intensity of 180 mph maximum sustained winds was reached on October 26?

There’s still lots of time left in this season. It ain’t over till the differently weighted lady sings!

[KWT]

Oh and what about Wilma as well...strongest ever syste, that was an October storm.

[Frank2]

I actually expect to see an out of season system this year in December.

Of course none of us know for sure but I'd say that's unlikely, since TWC mentioned that a early-early Fall cold front is already moving through the northern Rockies with temps up to 15 degrees below normal, so if it's already frosting in the high meadows this early it's often a sign of an early Fall season everywhere...

Besides, the last 3 2005 systems were not here but in the northeast Atlantic - about 4,000 miles from here (per the "Greek alphabet" list)...

Frank

[ColinDelia]

This will be useful as the season goes on

Average date upon which the nth Atlantic storm of the season is named (1966-2009)

1. July 9
2. Aug 1
3. Aug 13
4. Aug 23
5. Aug 31
6. Sep 8
7. Sep 16
8. Sep 24
9. Oct 4
10. Oct 19
11. Nov 23

Source: http://www.nhc.noaa.gov/pastprofile.shtml

[ColinDelia]

Average date upon which the nth Hurricane forms (1966-2009)

1. Aug 10
2. Aug 28
3. Sep 9
4. Sep 21
5. Oct 7
6. Nov 23

Category 3 or greater

1. Sep 4
2. Oct 3

[Portastorm]

Early cold fronts are very typical for a La Nina pattern, especially for the Rockies eastward.

I actually expect to see an out of season system this year in December.

Of course none of us know for sure but I'd say that's unlikely, since TWC mentioned that a early-early Fall cold front is already moving through the northern Rockies with temps up to 15 degrees below normal, so if it's already frosting in the high meadows this early it's often a sign of an early Fall season everywhere...

Besides, the last 3 2005 systems were not here but in the northeast Atlantic - about 4,000 miles from here (per the "Greek alphabet" list)...

Frank

[Cryomaniac]

I personally think that 18 NS is still just about possible. It's pretty unlikely, but all it takes is a flurry of storms at the end of August (say from the 20th to the end of the month) and then a busy September and October, with one or two in November or even December.

[ColinDelia]

Some interesting data I compiled. Here are the 10 busiest Atlantic seasons since 1851
with the number of storms (tropical storms +) and the number of storms by Aug 12.
5 of the 10 busiest seasons in history had 3 or less tropical storms by Aug 12.

10 busiest seasons | Number of storms | Storms by Aug 12

2005 28 9
1933 21 6
1995 19 7
1887 19 5
1969 18 2
2008 16 5
2003 16 4
1936 16 7
2007 15 3
2004 15 3
2001 15 3
2000 15 1

[ColinDelia]

So 7 of the 10 busiest Atlantic seasons in history were in the past 10 years.

[ronjon]

Dr Jeff Masters Addresses the "quiet" season so far. Interesting read.

Why so quiet in the Atlantic?

The Tropical Atlantic is quiet, and there are no threat areas to discuss today. The Invest 93 system we were tracking has been destroyed by dry air and wind shear. There are a couple of long-range threats suggested by some of the models--the GFS model predicts a tropical depression could form off the coast of Mississippi six days from now, and the NOGAPS model thinks something could get going in the Gulf of Mexico's Bay of Campeche seven days from now. Neither of these possibilities are worthy of concern at present. Overall, it's been a surprisingly quiet August, considering the pre-season predictions of a hyperactive season. According the National Hurricane Center, this hurricane season has been exactly average so far. There have been three named storms and one hurricane as of August 12. The average date of formation of the third named storm is August 13. One hurricane typically forms by August 10. One reason for this year's inactivity may be an unusual number of upper-level low pressure systems that have paraded across the tropical Atlantic. These lows, also called Tropical Upper Tropospheric Trough (TUTT) lows, tend to bring high wind shear that inhibits tropical cyclone formation. The other major factor appears to be that vertical instability has been unusually low in the Atlantic over the past month. Instability is measured as the difference in temperature between the surface and the top of the troposphere (the highest altitude that thunderstorm tops can penetrate to.) If the surface is very warm and the top of the troposphere is cold, an unstable atmosphere results, which helps to enhance thunderstorm updrafts and promote hurricane development. Since SSTs in the Atlantic are at record highs, enhancing instability, something else must be going on. Dry air can act to reduce instability, and it appears that an unusually dry atmosphere over the Atlantic this month is responsible for the lack of instability.

A record quiet start to the 2010 tropical cyclone season in the Northern Hemisphere

What is really odd about this year, though, is the lack of tropical cyclone activity across the entire Northern Hemisphere. Usually, if one ocean basin is experiencing a quiet season, one of the other ocean basins is going bonkers. That is not the case this year. Over in the Eastern Pacific, there have been five named storms and two hurricanes. The average is seven named storms and four hurricanes for this point in the season. This year's quiet season is not too surprising, since there is a moderate La Niña event underway, and La Niña conditions usually supresses Eastern Pacific hurricane activity. But over in the Western Pacific, which usually generates more tropical cyclones than any ocean basin on Earth, it has been a near-record quiet season. Just four named storms have occurred in the West Pacific this year, and the average for this date is eleven. Only one typhoon season has had fewer named storms this late in the season--1998, with just three. The total number of named storms in the Northern Hemisphere thus far this year is fifteen, which is the fewest since reliable records began in 1948. Second place belongs to 1983 and 1957, with eighteen named storms. According to an email I received from NOAA hurricane researcher Gabe Vecchi, the lack of tropical cyclones so far this year in the Northern Hemisphere is between a 1-in-80 and 1-in-100 year event.

So, what is causing this quiet tropical cyclone season? One possibility is that since Northern Hemisphere land areas have heated up to record temperatures this summer, this has created strong rising motion over the continents. This rising motion must be compensated by strong sinking motion over the adjacent oceans in order to conserve mass. Sinking air causes drying and an increase in stability. Another possibility is that the unusual jet stream configuration that is responsible for the Russia heat wave and record flooding in Pakistan is also bringing dry, stable air to the Northern Hemisphere's tropical cyclone breeding grounds. It is also possible that climate change is causing the reduction in tropical cyclone activity, for a variety of complex reasons. Computer simulations of a future warmer climate generally show a reduction in global number of tropical cyclones (though the strongest storms get stronger), and it is possible we are seeing a preview of that future climate. Or, this year's quietness may simply be natural variability. It will be interesting to see when the Russian heat wave breaks if vertical instability over the Atlantic increases back to normal levels. Current forecasts from the GFS and ECMWF models project the Russian heat wave to break late next week.

[HurricaneJoe22]

Some interesting data I compiled. Here are the 10 busiest Atlantic seasons since 1851
with the number of storms (tropical storms +) and the number of storms by Aug 12.
5 of the 10 busiest seasons in history had 3 or less tropical storms by Aug 12.

10 busiest seasons | Number of storms | Storms by Aug 12

2005 28 9
1933 21 6
1995 19 7
1887 19 5
1969 18 2
2008 16 5
2003 16 4
1936 16 7
2007 15 3
2004 15 3
2001 15 3
2000 15 1

This should quiet all this "season is dead" speculation.

[KWT]

Yeah we are keeping up with most of the 15-18NS seasons, but we do need to get something decent form soon if we are to keep up with those seasons to be fair.

[Cryomaniac]

Some interesting data I compiled. Here are the 10 busiest Atlantic seasons since 1851
with the number of storms (tropical storms +) and the number of storms by Aug 12.
5 of the 10 busiest seasons in history had 3 or less tropical storms by Aug 12.

10 busiest seasons | Number of storms | Storms by Aug 12

2005 28 9
1933 21 6
1995 19 7
1887 19 5
1969 18 2
2008 16 5
2003 16 4
1936 16 7
2007 15 3
2004 15 3
2001 15 3
2000 15 1

This should quiet all this "season is dead" speculation.

Emphasis on the word "should"...