Disturbed weather in Eastern Atlantic (Is invest 95L)

[Aric Dunn]

an area of interest should persist for 24hours ... for some reason the link to NRL requirements I had no longer work seems they changed their site. The only thing i can find is the TCFA checklist.. let me keep looking..

The TCFA checklist has nothing to do with whether or not an invest is tagged. Fact is, there isn't any requirement. As long as the forecaster in charge at the NHC is interested in the area and wants to run model plots, etc... If it is the forecasters' preference to wait for 24 hours of persistent convection, it's his choice. As for me, I've seen plenty of convective persistence already.

yes I know the TCFA does not ... was just mentioning thats all i could find at all with a reference to a invest .. lol

[summersquall]

From the NHC site glossary:

Invest:
A weather system for which a tropical cyclone forecast center (NHC, CPHC, or JTWC) is interested in collecting specialized data sets (e.g., microwave imagery) and/or running model guidance. Once a system has been designated as an invest, data collection and processing is initiated on a number of government and academic web sites, including the Naval Research Laboratory (NRL) and the University of Wisconsin Cooperative Institute for Meteorological Satellite Studies (UW-CIMSS). The designation of a system as an invest does not correspond to any particular likelihood of development of the system into a tropical cyclone; operational products such as the Tropical Weather Outlook or the JTWC/TCFA should be consulted for this purpose.

[MiamiHurricanes10]

yes I know the TCFA does not ... was just mentioning thats all i could find at all with a reference to a invest .. lol

LOL, ok.

[MiamiHurricanes10]

From the NHC site glossary:

Invest:
A weather system for which a tropical cyclone forecast center (NHC, CPHC, or JTWC) is interested in collecting specialized data sets (e.g., microwave imagery) and/or running model guidance. Once a system has been designated as an invest, data collection and processing is initiated on a number of government and academic web sites, including the Naval Research Laboratory (NRL) and the University of Wisconsin Cooperative Institute for Meteorological Satellite Studies (UW-CIMSS). The designation of a system as an invest does not correspond to any particular likelihood of development of the system into a tropical cyclone; operational products such as the Tropical Weather Outlook or the JTWC/TCFA should be consulted for this purpose.

No requirements there.

[Aric Dunn]

From the NHC site glossary:

Invest:
A weather system for which a tropical cyclone forecast center (NHC, CPHC, or JTWC) is interested in collecting specialized data sets (e.g., microwave imagery) and/or running model guidance. Once a system has been designated as an invest, data collection and processing is initiated on a number of government and academic web sites, including the Naval Research Laboratory (NRL) and the University of Wisconsin Cooperative Institute for Meteorological Satellite Studies (UW-CIMSS). The designation of a system as an invest does not correspond to any particular likelihood of development of the system into a tropical cyclone; operational products such as the Tropical Weather Outlook or the JTWC/TCFA should be consulted for this purpose.

No requirements there.

go back a page and read the exchange of emails from southergale and the NHC... there is no formal criteria but it does need to have basic requirements that are common sense..

[Vortmax1]

Sorry gang...we have Invest 192 in the EPAC first!


https://my.sfwmd.gov/portal/page/portal ... tab2200108

[Ivanhater]

Starting to get off topic. If you want, continue the discussion about invest criteria via PM.

[cycloneye]

Ivan is right. Lets continue the discussions about this complex system.

[wxman57]

I think there is some confusion as to what this paper is saying. It appears that the author is discussing using the NAO values from October-January of the previous winter to predict landfalls 6 months into the future - the next hurricane season. He says that a weak NAO (negative) in the previous Oct-Jan could lead to high pressure across the western Atlantic basin (+NAO) and less recurving storms in the upcoming hurricane season. He's not saying a current -NAO results in more landfalls.

No, it is just a normal article that helps to forecast what would happen 6 months in advance, it has nothing to so with what is going to happen in the 2011 season.

Anyways, why would that negative NAO be any different to this one?

You're not understanding. The author is talking about a negative NAO during the previous winter, like October 2009 to January 2010 as being a predictor for landfalling storms in the coming summer of 2010. He's not stating that a CURRENT -NAO will lead to less recurving storms. Just the opposite, in fact. A current negative NAO results in a weaker and eastward-displaced Bermuda High and a deeper trof along/off the East U.S. Coast. That leads to early recurvature for a storm that's moving westward far enough to the north.

PM me to discuss further if you like.

[CrazyC83]

Where is it that a circulation would likely form, the blob at 20W, 22W or 28W?

[cycloneye]

This bouy is near the area of possible LLC that may be forming. Plenty of West,WSW winds.

http://www.ndbc.noaa.gov/station_page.php?station=13001

Code: Select all

 
08 19 2000   11.46 -23.00 SW 6 - 29.81 - - 82.8
08 19 1600   11.47 -22.99 WSW 15 - 29.78 - - 82.8
08 19 1400   11.46 -23.00 W 12 - 29.82 - - 82.9
08 19 1100   11.46 -22.99 WSW 19 - 29.85 - - 82.9
08 19 0800   11.46 -23.00 WSW 21 - 29.79 - - 82.9
08 19 0500   11.46 -22.99 WSW 20 - 29.79 - - 83.1
08 19 0300   11.46 -22.99 W 22 - 29.80 - - 83.1
08 18 2100   11.47 -23.01 WNW 16 - 29.85 - - 83.3
08 18 1700   11.47 -23.01 WSW 18 - 29.83 - - 83.3
08 18 1600   11.47 -23.00 WSW 18 - 29.83 - - 83.3
08 18 1400   11.47 -23.01 W 12 - 29.88 - - 83.5


[CrazyC83]

I really don't like the looks of this at all. ALREADY an LLC? West winds in the 20s certainly qualifies for one - a 25 kt TD already perhaps? And it hasn't even cleared Cape Verde yet!

[lonelymike]

All the NAO forecasts I've seen have it headed toward a positive phase by the end of the month. This would favor more dominant ridging over the Atlantic basin and lead to more westward traveling CV Storms!

Dean do you have a link to those forecasts? Everything I've read is just the opposite. Not doubting your word

[StormTracker]

Aric, what do you think about this?

[img]http://a.imageshack.us/img714/7877/movie9262355.gif

Well Im not sure if you saw my post from this morning where Made a image of the surface analysis? but the greatest vorticity this morning was farther west and has shifted east a little. there is two areas at least this morning that had small eddy's. the overall system is embedded in the ITCZ and is quite elongated with multiple waves interacting. the farthest east portion a little better curvature. This what I think should happen... the farthest east part should begin moving wnw while the western portion drops wsw and at some point in the next 2 days a LLC should form in the middle of a tilted SW to NE trough of low pressure... basically what we are looking at now just tilted. if you turn on the surface obs and ship reports you can see the low level flow. but will see these things are tricky and with so many little vorticity it will be hard to pin point a LLC forming until we get a some decent organized convection.

Aric, as this was being posted I was thinking, could the ITCZ affect this situation any? Is that what may make the western portion of the vorticity head WSW, or is it the tilt(SW-NE) of the trough that would make it dip WSW?

[Dean4Storms]

All the NAO forecasts I've seen have it headed toward a positive phase by the end of the month. This would favor more dominant ridging over the Atlantic basin and lead to more westward traveling CV Storms!

Dean do you have a link to those forecasts? Everything I've read is just the opposite. Not doubting your word

Here ya go.... Note the last 500 z 14day forecast by the GFS shows it reaching positive.

http://www.accuweather.com/blogs/meteom ... -chart.asp

[Ivanhater]

[Tropics Guy]

Developing circulation evident on latest E Atl Sat pics, all systems go for this one, IMO should be an invest by the morning.............

http://www.ssd.noaa.gov/eumet/eatl/loop-avn.html

TG

[knotimpaired]

I think what you should understand is that Storm2k is the weather bible on our island of Vieques.

Our goddesses and gods which work in our restaurant/bars here take care of us year round. The end of August till October is their time to head north and when everyone has doom in the radar it does not make them happy to leave their homes.

So chill, speak when you know something, do not worry your friends.

K

[supercane]

This bouy is near the area of possible LLC that may be forming. Plenty of West,WSW winds.

I really don't like the looks of this at all. ALREADY an LLC? West winds in the 20s certainly qualifies for one - a 25 kt TD already perhaps? And it hasn't even cleared Cape Verde yet!

Except that the westerly winds are not solely associated with a single LLCC but instead are related to the broad low-level westerlies south of the monsoon trough axis the NHC noted in their discussion. As previously posted above:

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 13N38W 11N47W 13N55W. EAST OF THE
TROPICAL WAVE BETWEEN 33W-38W...A MONSOONAL TROUGH IS ANALYZED
AS A SURFACE TROUGH IN PLACE OF THE ITCZ FROM EASTERN MAURITANIA
NEAR 19N06W TO THE W AFRICA COAST NEAR 14N17W AND INTO THE E
ATLC TO 13N27W. THIS MONSOONAL TROUGH HAS PERSISTED OVER THE
PAST FEW DAYS WITH WESTERLY LOW-LEVEL FLOW OBSERVED S OF 13N. AN
EARLIER MORNING ASCAT PASS AROUND 19/1054 UTC INDICATED THE
BEGINNINGS OF A BROAD LOW-LEVEL CIRCULATION SW OF THE CAPE VERDE
ISLANDS NEAR 13N26W.

[Vortmax1]

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.



Next Atlantic Hurricane Could Form by Early Next Week


While the season has been fairly quiet so far, Bastardi expects a "frenzy of activity the rest of the way."

In fact, the next hurricane of the season could develop by early next week. The AccuWeather.com Hurricane Center is monitoring an area of disturbed weather south of the Cape Verde Islands.




http://www.accuweather.com/blogs/news/s ... -could.asp