ATL: INVEST 94L - DISCUSSION

[thetruesms]

Convergence and Divergence, look in the bottom of the graphs and you will see the names

Is convergence where the winds split into different directions and divergence is where the winds come from different directions to the same point? At what level is the convergence/divergence, and what is the significance of it?

Convergence or converge, is where winds come together at the surface, and divergence or diverge, is where winds separate at the upper levels, allowing the storm to "breath."

Convergence and divergence can take place at any level. However, as you can tell from the plots' titles, they are concentrating on the low level convergence and upper level divergence that HURAKAN is describing.

edit - on a side note, convergence and divergence are really the same thing, just with flipped signs (i.e. convergence is negative divergence)

[HURAKAN]

Thanks thetruesms. Makes sense.

[I-wall]

Thanks to both of you for the explanation.

[HURAKAN]

Thanks to both of you for the explanation.

No problem! Convergence and divergence is something I always look to see how is the environment. 92L had low shear at the beginning and a great circulation, but didn't have convergence. If winds can't converge at the center of the storm and bring the moist air to produce thunderstorms, then there can't be a storm. I think 94L has a shot despite the shear bc it has a great vorticity, good convergence and divergence. Shear maps decrease the shear over the next few days but we know how good those shear forecasts are!!

24 hours ..


48 hours ..

[JTD]

If Alex and Bonnie form by June 27th, 2010 will be ahead of 2005 as Bret formed on June 28, 2005.

If 2010 gets both Alex and Bonnie by June 29th, I will consider 2010 so far to be on par with 2005. Then, we will need to wait to see if 2010 continues to churn out storms at quite a pace.

It'll be interesting to see if Alex and Bonnie attain no more than tropical storm status as both Arlene and Bret in 2005 were tropical storms.

This is what I meant in my post of a week ago. Hyperactive seasons usually see 1-2 June storms. The fact that we have potentially 2 named storms in June this year is concerning.

[Hugo1989]

are this system will pass far from Puerto Rico? are saying?

[HURAKAN]

are this system will pass far from Puerto Rico? are saying?

Should pass north of the Caribbean

[Hugo1989]

are this system will pass far from Puerto Rico? are saying?

Should pass north of the Caribbean

it should be happen the same that happened to 92L? or be can developed?

[HURAKAN]

are this system will pass far from Puerto Rico? are saying?

Should pass north of the Caribbean

it should be happen the same that happened to 92L? or be can developed?

If it can survive the shear, it has a chance.

[HURAKAN]

Loop

[KWT]

Ohhhh....

This is starting to look already like a system, I'm not sure how its strengthening mind you given its near a jet axis...but still looks like this one could also develop...

Looks like the good conditions aloft from the EPAC are working over...things about to kick start.

[HURAKAN]

Yeah, KWT, it has a nice twist. Wouldn't be surprised to see a LLC develop tonight if convection develops during D-MAX.

[artist]

Ohhhh....

This is starting to look already like a system, I'm not sure how its strengthening mind you given its near a jet axis...but still looks like this one could also develop...

Looks like the good conditions aloft from the EPAC are working over...things about to kick start.

my thoughts exactly. This is not good! Have you guys noticed all these systems including the east pac are basically in a line as such? For this amateur did they all start from the itcz?

[KWT]

Yeah, KWT, it has a nice twist. Wouldn't be surprised to see a LLC develop tonight if convection develops during D-MAX.

Well there is certainly a nice MLC present with this system from the looks of things, whenever you see that sort of curling effect develop it tends to mean development into a highly sheared system is possible...

[Gustywind]

For info due to the proximity and the effects expected of 94L this week, Meteo-France have issued an yellow alert for the Northern Leewards, Guadeloupe and Martinica too.
Here's is the link for those who wanted to improve their french related to 94L http://www.meteo.gp/EspacePro/Bulletins ... e=spe_gene

Based on Meteo-France's latest weather forecast Basse-Terre have alreday experienced nice amounts of water today: up to 120 millimeters! I will be glad to have HUC's (our friend from Basse-Terre in Guadeloupe) measurements today, hope that he will read this post.
This active twave should continue to bring values near 70 to 100 millimeters even more : 200 millimeters near the hills given Meteo-France.
We should stay vigilant and prudent us in the east and northeast Leewards.
This episode (the second in less than 1 week! not so ba for June) is expected to bring strong showers and tstorms until Sunday morning. Stay tuned, stay and dry all my friends in the Carib! I will keep your informed as usual and as possible.
Gustywind

[Gustywind]

http://www.meteo.gp/index.php?page=Incl ... e=spe_gene
Link (french version) fro those who wanted to improve their french

[cycloneye]

TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT FRI JUN 25 2010

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON NEWLY FORMED
TROPICAL DEPRESSION ONE...LOCATED ABOUT 345 MILES SOUTHEAST OF
COZUMEL MEXICO.

A LARGE BUT DISORGANIZED AREA OF CLOUDINESS AND SHOWERS CENTERED
JUST EAST OF THE NORTHERN LEEWARD ISLANDS IS ASSOCIATED WITH A
TROPICAL WAVE INTERACTING WITH AN UPPER-LEVEL TROUGH. THERE IS THE
POTENTIAL FOR SOME SLOW DEVELOPMENT OF THIS SYSTEM AS IT MOVES
TOWARD THE NORTHWEST AT 10 TO 15 MPH. THERE IS A LOW CHANCE...20
PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE
NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

PUBLIC ADVISORIES ON TROPICAL DEPRESSION ONE ARE ISSUED UNDER
WMO HEADER WTNT31 KNHC AND UNDER AWIPS HEADER MIATCPAT1.
FORECAST/ADVISORIES ON TROPICAL DEPRESSION ONE ARE ISSUED UNDER WMO
HEADER WTNT21 KNHC AND UNDER AWIPS HEADER MIATCMAT1.

$$
FORECASTER BRENNAN

[Gustywind]

Code Yellow

[Gustywind]

000
AXNT20 KNHC 260008
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT FRI JUN 25 2010

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST
FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED
ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 2345 UTC...

...TROPICAL WAVES...

TROPICAL WAVE IS ALONG 64W S OF 17N MOVING W-NW 10-15 KT. THE
NORTHERN HAL OF THE WAVE IS EMBEDDED WITHIN AN AREA OF MID TO
HIGH VALUES OF DEEP LAYERED MOISTURE AS DEPICTED ON THE TOTAL
PRECIPITABLE WATER IMAGERY. THEREFORE...THE CONVECTION
ASSOCIATED WITH THIS WAVE IS FROM 15N TO 20N BETWEEN 61W AND
68W...AFFECTING THE US/UK VIRGIN ISLANDS AND PUERTO RICO.
LOCALIZED FLOODING MAY BE POSSIBLE OVER AREAS WHERE THE TERRAIN
IS ALREADY SATURATED FROM PREVIOUS RAINFALL EVENTS.
FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$

GARCIA

[KWT]

I still feel this one could develop, don't think it'll do it just yet despite a very good MLC at the moment however.