2006 Atlantic Hurricane Season Thoughts.

[kold weather]

As it happens SB according to Dr.Gray, The west phase of the QBO has been shown to provide more favorable conditions for development of tropical cyclones in the deep tropics then the easterly phase of the QBO.

[Kain]

I know I'm abit thick, but what makes a storm Extra-Tropical?

Is it simply the latitude of the storm? Or a more physical change?

Kain

[Paranoid]

A storm goes Extratropical when it loses tropical characteristics, it often happens when they reach higher latitudes, or if the condititions suddenly become unfavourable. Some storms remain tropical for a long time after leaving the tropics, like Faith in 1966 and Debby in 1961.

[crimsone]

A storm goes Extratropical when it loses tropical characteristics, it often happens when they reach higher latitudes, or if the condititions suddenly become unfavourable. Some storms remain tropical for a long time after leaving the tropics, like Faith in 1966 and Debby in 1961.

Just as a thought, could the extra tropical transition be said to occur when the actual velocity/pressure/power of a tropical storm becomes greater than the MPI suggested by the area it is in? (or perhaps in other words, the inertia suggests cat 3 but the convection isn't there to support anything more than a cat 2, for example)

Edited April 22, 2006 by crimsone

[Methuselah]

I know I'm abit thick, but what makes a storm Extra-Tropical?

Is it simply the latitude of the storm? Or a more physical change?

Kain

Well I may be completely up Schitt Creek with this...But my guess is that a storm becomes extratropical the moment it becomes frontal??? :blush:

That is: assuming that it ever does! :blush: :blush: :lol:

[Paranoid]

They can get absorbed by larger non-tropical lows or fronts, and become an extratropical storm. Some people speculate this is how the Great Storm of 1987 formed, when a low absorbed Hurricane Floyd. The risk of a tropical system being absorbed generally gets higher as it moves further northeast. (In the Atlantic anyway)

If you want to know more, i suggest posting the question in the learners area. I find they can give a lot of good answers)

Edited April 22, 2006 by Paranoid

[wolves78]

91L.INVEST 310N-720W

prob wont ammount to much but will the season start early?

[kold weather]

Hi wolves, no it won't, but it didn't look that bad yesterday, at least in terms of circulation, though it is a naked swirl and under still pretty chilly sea temps for any tropical actvity to happen, so no it won't amount to anything I'd have thought, maybe a tiny tiny outside chance of something sub-tropical, but I'd rate that at less then 2% chance.

So now on, if you want to talk about a invest, make a new topic about it, further more if the invest is upgraded then I'll change the name of the thread so there is no need to make a new one!!!!

[wolves78]

QUOTE KOLD weather

So now on, if you want to talk about a invest, make a new topic about it, further more if the invest is upgraded then I'll change the name of the thread so there is no need to make a new one!!!!

just thought id pop it here mate as i looked at the title of this thread 2006 Atlantic Hurricane Season Thoughts., ALL atlantic hurricane season talk here

as it was such a short lived thing it would have been a waste of a new topic

[summer blizzard]

THE CARIBBEAN SEA...

THE TAIL END OF A STATIONARY FRONT IS OVER THE VIRGIN ISLANDS. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE OVER THE VIRGIN ISLANDS...PUERTO RICO...AND HISPANIOLA FROM 15N-22N BETWEEN 60W-74W. SAN JUAN RADAR SHOWS ACTIVITY ALL AROUND THE ISLAND OF PUERTO RICO. ELSEWHERE... NUMEROUS STRONG CONVECTION IS INLAND OVER N COLOMBIA FROM 7N-10N BETWEEN 73W-78W. TRADEWINDS ARE RELATIVELY LIGHT OVER THE CARIBBEAN SEA. IN THE UPPER LEVELS... A RIDGE IS OVER THE CARIBBEAN N OF 10N. STRONG SUBSIDENCE IS OVER THE CARIBBEAN SEA EXCEPT ALONG THE N COAST OF

S AMERICA S OF 12N BETWEEN 60W-78W. EXPECT THE SHOWERS OVER THE LEEWARD ISLANDS TO CONTINUE DURING THE NEXT 24 HOURS. ALSO EXPECT THE SRN CARIBBEAN S OF 13N TO HAVE GOOD POTENTIAL FOR CONVECTION AND SHOWERS.

Looks like there is potential in the southern Carribean.

[summer blizzard]

In regards to the upcoming hurricane season, while things are looking good for another early start to the hurricane season, i believe that the QBO will be in a positive (westerly) mode meaning that the Bermuda-Azores High will be displaced eastward so that westerly sheer will be prevalant in the Carribean so that the majority of tropical development will occur in the Atlantic, on top of that, i expect El Nino conditions to develop during July, so here are my thoughts for the hurricane season.

May - 0 tropical storms

June - 2 tropical storms

July - 3 tropical storms

August - 2 tropical storms

September - 2 tropical storms

October - 1 tropical storm

In conclusion, i expect a average number of named storms to develop this season with the majority of named storms forming in the tropical Atlantic before curving northward leading to a above average number of named storms hitting the east coast of America, i do expect a above average start to the hurricane season and should no El Nino develop during July, then my estimate may be revised upward.

[P.K.]

None of the models are predicting a warm ENSO event this summer. http://www.bom.gov.au/climate/ahead/ENSO-summary.shtml The latest update is here, although the next update will be out within a few hours.

Summary: Pacific remains neutral. Cool phase nearly over

The recent cool phase in the Pacific, which briefly approached La Niña-like conditions, is showing signs of decay. Sea-surface temperatures have continued to warm in the central to eastern Pacific and are now close to average. More importantly, the large body of cooler than average sub-surface water in the east has contracted considerably during the past month.

Nonetheless, the SOI has continued to rise, with the latest 30-day value being about +18. In addition, cloudiness remains strongly suppressed around the date-line. While both the SOI and the cloud are continuing to show behaviour consistent with a La Niña, large-scale coupling between the Pacific atmosphere and ocean is generally weak or absent in the southern autumn.

Computer modelling predictions of Pacific temperatures mostly indicate warming over the next few seasons, with neutral conditions in the southern winter and spring. It should be noted, however, that due to the aforementioned weak large scale coupling at this time of the year, March to June is the period when predictability of future ENSO conditions is at its lowest.

[summer blizzard]

I was refering to the Met Office El/La Nina ensemble forecasts, the mean of this shows neutral to El Nino conditions developing during July. (0 - 1 value)

[kold weather]

It looks like a nuetral summer to me to be honest, I'd be very suprised indeed if we did have a El nino by even next Autumn yet alone this summer, looks like nuetral condtions.

One other thing that must be mentioned is the increase in Sea surface temps across most of the atlantic basin, TNA data hasn't come out yet (At least I don't think so!!!) but for sure it'll be an increase on March's temps, probably upto 0.45c I'd guess.

Also worth saying that the gulf is massivly above average, with the shallow waters by the coast 3C above average and even the deeper water is a good 1.5C above.

[crimsone]

shallow waters by the coast 3C above average and even the deeper water is a good 1.5C above.

Which implies that it's still warming up, does it not? (being a differential between the deep and the shallow - the shallow being the first thing to warm and the first thing to cool)

[crimsone]

possible activity in the pacific? From the NHC tropical discussion for the pacific as of now...

W OF 110W...

MID/UPPER LEVEL SHEAR AXIS OVER THE EXTREME NW PART OF THE AREA

IS ALONG 30N131W 27N140W AS A CUT-OFF LOW DEVELOPS W OF THE AREA

NEAR THE HAWAIIAN ISLANDS AND DETACHES FROM A MID-LATITUDE

TROUGH OFF THE W COAST OF THE US. THE UPPER FLOW S OF HAWAII IS

ZONAL BUT THEN SPLITS NEAR 137W WITH THE FLOW S OF 10N TURNING

SE TOWARDS THE EQUATOR...AND THE REMAINDER CURVING NE TOWARDS

THE BAJA PENINSULA AND CNTRL MEXICO. THE DIFFLUENCE RESULTING

FROM THE SPLITTING FLOW...AS WELL AS AN UPPER RIDGE ALONG

15N...IS ENHANCING ITCZ CONVECTION BETWEEN 106W-130W WITH THE

CIRRUS DEBRIS HEADING TOWARDS THE W MEXICAN COAST. THE ITCZ IS

ALSO BECOMING INCREASINGLY PERTURBED IN THIS REGION WITH A LOW/

MID-LEVEL TROUGH LOCATED ALONG 8N118W 13N113W. THE CONVECTION

AROUND THIS FEATURE REMAINS DISORGANIZED AND HAS DISSOLVED OVER

THE PAST FEW HOURS...BUT THERE IS MORE MID-LEVEL ROTATION IN THE

CLOUD SYSTEM AS COMPARED TO YESTERDAY. A SECOND TROUGH IS

LOCATED WITHIN THE ITCZ ALONG 128W BUT IT HAS VERY LITTLE

STRUCTURE.

[Guest Mr_S]

ITCZ? Whats that stand for? :o anyone know?

Edited May 7, 2006 by Mr_S

[Mondy]

Google is your friend http://iri.ldeo.columbia.edu/~bgordon/ITCZ.html

The Intertropical Convergence Zone

[tinybill]

In regards to the upcoming hurricane season, while things are looking good for another early start to the hurricane season, i believe that the QBO will be in a positive (westerly) mode meaning that the Bermuda-Azores High will be displaced eastward so that westerly sheer will be prevalant in the Carribean so that the majority of tropical development will occur in the Atlantic, on top of that, i expect El Nino conditions to develop during July, so here are my thoughts for the hurricane season.

May - 0 tropical storms

June - 2 tropical storms

July - 3 tropical storms

August - 2 tropical storms

September - 2 tropical storms

October - 1 tropical storm

In conclusion, i expect a average number of named storms to develop this season with the majority of named storms forming in the tropical Atlantic before curving northward leading to a above average number of named storms hitting the east coast of America, i do expect a above average start to the hurricane season and should no El Nino develop during July, then my estimate may be revised upward.

here are the names for the hurrican season

Aletta

Bud

Carlotta

Daniel

Emilia

Fabio

Gilma

Hector

Ileana

John

Kristy

Lane

Miriam

Norman

Olivia

Paul

Rosa

Sergio

Tara

Vicente

Willa

Xavier

Yolanda

Zeke

[summer blizzard]

...TROPICAL WAVES...

TROPICAL WAVE IS CENTERED ALONG 32W S OF 9N MOVING W 10-15 KT. THE WAVE IS LOW AMPLITUDE IN SCOPE BUT STILL PRESENTS A FAIRLY WELL DEFINED SIGNATURE ON SATELLITE IMAGERY. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS MOSTLY ALONG THE ITCZ FROM 3N-7N BETWEEN 30W-37W.

http://www.nhc.noaa.gov/text/refresh/MIATW...ml/111800.shtml?

http://www.nhc.noaa.gov/tafb/ATSA_12Z.gif

[crimsone]

Regarding that Tropical Wave, it's just about to enter the Atlantic discussion area...

from discussion of 0005z...

...TROPICAL WAVES...

TROPICAL WAVE IS ALONG 48W S OF 10N MOVING W 10 KT. VISIBLE

SATELLITE IMAGERY SHOWS A SMALL SWIRL OF LOW CLOUDS ON THE WAVE

AXIS NEAR 7N48W...MOVING SLOWLY TO THE W. ISOLATED TSTMS ARE

ASSOCIATED WITH THE WAVE FROM 6N-10N. SCATTERED SHOWERS AND

POSSIBLE ISOLATED TSTMS ARE EAST OF THE WAVE AXIS TO 44W.

Does anyone give this one any chance of development? TD perhaps?

[crimsone]

Once more regarding that tropical wave, as of Atlantic tropical discussion at 1205z today...

...TROPICAL WAVES...

TROPICAL WAVE ALONG 51W S OF 10N MOVING W 10 KT. SUSPECTED

SMALL SWIRL OF LOW CLOUDS ON WAVE AXIS NEAR 6N EMBEDDED IN ITCZ.

CONVECTION HOLDING TOGETHER OVERNIGHT INCREASING IN AMOUNT AND

CONCENTRATING NOW FROM 8N-10N WITHIN 120 NM OF WAVE AXIS.

Something appears to be organising, but is it a "flash in the pan", or will something more significant come from it?

[Mondy]

Its probably just the ITCZ beginning to reawaken.

[Dawlish]

Nothing like as early as possibly happened in 1908!

"According to NOAA's National Hurricane Center, the season's earliest Atlantic hurricane ever recorded was on March 7th, 1908"

http://www.ncdc.noaa.gov/oa/climate/resear...rricanes03.html

Hurricanes are rare, but certainly not unknown outside of the official "season" of June 1st. to Nov 30th.

I don't think the number of Atlantic hurricanes is anything like as inportant as the strength. With warming sea temperatures worldwide, one would expect the strength of the hurricanes to increase. Then, of course, it is down to pure luck as to whether this kind of category 5 hurricane makes landfall, especially in a heavily populated area.

With global warming and more energy in the atmospheric system, will a category 6 ever have to be considered?

[kold weather]

Very intresting post Dawlish. Global watrming doesn't seem to have increased the numbers of tropical cyclones and globally they have in fact ever so slightly reduced from the last 30 years. The strength issue though is uncertain. Certainly in the Atlantic there has been a increase in overall strength with many more hurricanes going on to become major hurricanes. As for a need for a cat-6, no because category-5 does mean complete destruction and you can't get much more complete then that, though I think there would be a idea to split it into 2 categories, with lower end category-5's such as Isabel and Ivan as cat-5a and then your stronger cat-5's like Wilma and Gilbert.

Waves comnig off Africa will become more and more common now as the ITCZ continues to migrate northwards and the sea's continue to heat up.