Atlantic ITCZ

[AussieMark]

this is where the ITCZ was in 2005 for the next sequence
i.e (may 21 - 31)

15°W: 10.5°N
10°W: 13.3°N
5°N: 15.4°N
0°: 17.3°N
5°E: 16.4°N
10°E: 14.5°N
15°E: 13.6°N
20°E: 13.5°N
25°E: 13.2°N
30°E: 14.5°N
35°E: 16.2°N

[cycloneye]

By the information above that Aquawind and AussieMark shared with us about where the ITCZ axis still the axis is more southward than normal for this time of the year and reinforces the position that wxman57 has said in the past few weeks about the ITCZ being this far south will cause less tropical developments early in the season as the waves will crash into South America and emerge into the EPAC.

[AussieMark]

between 10W and 10E is more south than usual




between 20 and 35E its more north than usual

[tgenius]

so in the grand scheme of things.. what does that translate to?

[no advance]

Cyclone I am not sure about that. Dont most early cyclones develop from stalled fronts or troughs.

[Ivan14]

Is there a model that can tell weather the ITCZ will move more south or north in the coming weeks?

[HurricaneHunter914]

http://www.ssd.noaa.gov/PS/TROP/DATA/RT/EATL/IR4/20.jpg

ITCZ is a little farther north right and looks pretty deep.

[skysummit]

It does look to be moving a little further north over Africa also.

http://cimss.ssec.wisc.edu/tropic/real- ... rmet7n.GIF

[Aquawind]

so in the grand scheme of things.. what does that translate to?

Gray and Landsea relate the African rainfall associated with the ITCZ and it's association with hurricanes.

http://www.aoml.noaa.gov/hrd/Landsea/sahel/index.html

Is there a model that can tell weather the ITCZ will move more south or north in the coming weeks?

I don't know of any particular model for the ITCZ location. It actually moves ~9 degrees of mean during the monitoring season April-Nov so little movement considering the overall scale. You can make it out pretty well on Satellite.

[Ivan14]

oh ok thanks.

[boca]

I just hope its inactive until early August when my hurricane shutters go up. I personally hope the ITCZ stays supressed so far south that everything hit South America before it can develop.

[caribepr]

I just hope its inactive until early August when my hurricane shutters go up. I personally hope the ITCZ stays supressed so far south that everything hit South America before it can develop.

Or...hits no land at all....

[gatorcane]

By the information above that Aquawind and AussieMark shared with us about where the ITCZ axis still the axis is more southward than normal for this time of the year and reinforces the position that wxman57 has said in the past few weeks about the ITCZ being this far south will cause less tropical developments early in the season as the waves will crash into South America and emerge into the EPAC

But the CV season doesn't start for a couple of months anyway - typically late July/August. There should be time for it to migrate north but an early CV storm in July based on this ITCZ information now is looking less likely - but certainly not out of the question.

[SouthFloridawx]

Yeah I agree with you Boca_Chris, the emphasis on the latitude of the ITCZ now is not as important as where it is in July/August. Typically we want to look for development in the western caribbean and GOM. Don't worry about the ITCZ it will make its yearly trek northward.

[Matt-hurricanewatcher]

These factors between this in the cool sst's is why I don't forecast more then 15 storms this year.

[wxmann_91]

Yeah I agree with you Boca_Chris, the emphasis on the latitude of the ITCZ now is not as important as where it is in July/August. Typically we want to look for development in the western caribbean and GOM. Don't worry about the ITCZ it will make its yearly trek northward.

Many waves that are the seedlings from TC's during the early season have their origins within the ITCZ. Later in the season the position of the ITCZ is more important to determine whether a certain CV storm will fish or hit land IMO.

[BayouVenteux]

Yeah I agree with you Boca_Chris, the emphasis on the latitude of the ITCZ now is not as important as where it is in July/August. Typically we want to look for development in the western caribbean and GOM. Don't worry about the ITCZ it will make its yearly trek northward.

Many waves that are the seedlings from TC's during the early season have their origins within the ITCZ. Later in the season the position of the ITCZ is more important to determine whether a certain CV storm will fish or hit land IMO.

Although it's important in that when the ITCZ is far enough south that the waves move west into the South American continent rather than the Caribbean sea, as it appears to be at present, you're going to have a lot less energy to work with in the areas that are climatologically favorable for early season development.

But, as SouthFloridawx said, it's only a matter of time before the ITCZ shifts north a few degrees.

[Aquawind]

The ITCZ is still getting pushed south as it exits the African Coast.. It does look much closer to normal..

During the period from May 21-31, 2006, the African portion of the Intertropical Convergence Zone was located near 13.6 degrees north latitude when averaged from 15W-35E over the ten day period. This compares to the normal location of 14.2N, and a position during the previous dekad of 13.5N. Areas to the west of Nigeria as well as to the east, are experiencing close to normal ITCZ position values when comparing it to the climatological mean. The current position has taken a jump to the north (Seen in figure 1) along the western half of Africa and has dipped to the south along the eastern half of Africa when comparing it to last dekads analysis. This ITCZ movement corresponds well with the accumulated dekadal rainfall. Examining figure 3 which depicts the ITCZ vs normal for the area of 20-35 degrees east, it is seen that after beginning the season well south of normal, the ITCZ rapidly moved northward last dekad and has now dipped back down to the south near normal. Additional information may be found at:

http://www.cpc.ncep.noaa.gov/products/f ... itcz.shtml


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

[cycloneye]

The ITCZ is still getting pushed south as it exits the African Coast.. It does look much closer to normal..

During the period from May 21-31, 2006, the African portion of the Intertropical Convergence Zone was located near 13.6 degrees north latitude when averaged from 15W-35E over the ten day period. This compares to the normal location of 14.2N, and a position during the previous dekad of 13.5N. Areas to the west of Nigeria as well as to the east, are experiencing close to normal ITCZ position values when comparing it to the climatological mean. The current position has taken a jump to the north (Seen in figure 1) along the western half of Africa and has dipped to the south along the eastern half of Africa when comparing it to last dekads analysis. This ITCZ movement corresponds well with the accumulated dekadal rainfall. Examining figure 3 which depicts the ITCZ vs normal for the area of 20-35 degrees east, it is seen that after beginning the season well south of normal, the ITCZ rapidly moved northward last dekad and has now dipped back down to the south near normal. Additional information may be found at:

http://www.cpc.ncep.noaa.gov/products/f ... itcz.shtml


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

Yep Paul,I haved been noticing that the ITCZ has creeped northward slowly in the past 2 weeks.But still is at a little southward position than normal for the begginning of June.

[OuterBanker]

Aqua,
I think CSU has dropped the African rainfall predictors.

from 6/06 abstract

"Since the observed shift of Atlantic Ocean SST patterns in 1995 [and the implied increase in the strength of the Atlantic Thermohaline Circulation (THC)], our original 1 June forecast scheme (1994) has consistently under-predicted Atlantic basin hurricane activity. Our earlier 1 June statistical scheme used West African rainfall data as an important predictor. We do not understand why, but the previously observed (1950-1994) strong association between West African rainfall and Atlantic hurricanes has not been reliable since 1994. We have lost confidence in the previous 1 June statistical forecast scheme compared to our newly developed one. We have thus decided to discontinue our earlier 1 June forecast scheme.