Development with Tropical Wave in MDR?

[Cyclone1]

If you really think about it. The NWS had to make a typo. How can a wave in the far eastern Atlantic effect our weather by this weekend. At what speed would it have to travel to inpact with even the drier side by this weekend???

Not that hard to imagine. Fast moving wave: Wednesday - E ATL, Thursday - Mid ATL, Friday - East Carib - Saturday - Antilles, Sunday - Bahamas/Florida?

Just proving a point of plausibility, not a forecast of any kind.

[Dean4Storms]

Air is just to dry and it is still too early to be getting to excited over these waves yet. Give it about a month!

[Gustywind]

000
AXNT20 KNHC 160003
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT WED JUL 15 2009

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 2315 UTC.

...TROPICAL WAVES...
A TROPICAL WAVE IS ALONG 26W S OF 15N MOVING W NEAR 15 KT.
SATELLITE IMAGERY SHOWS SOME MID-LEVEL CYCLONIC FLOW IN THE
VICINITY OF THIS WAVE. THIS WAVE ALSO COINCIDES WITH A LOW
AMPLITUDE DEEP LAYER MOISTURE MAXIMUM OBSERVED ON TOTAL
PRECIPITABLE WATER IMAGERY. ISOLATED MODERATE CONVECTION IS
FROM 6N-12N BETWEEN 24W-29W.

A TROPICAL WAVE IS ALONG 42W/43W S OF 16N MOVING W NEAR 15 KT.
THIS WAVE COINCIDES WITH A LOW AMPLITUDE DEEP LAYER MOISTURE
MAXIMUM OBSERVED ON TOTAL PRECIPITABLE WATER IMAGERY. NO DEEP
CONVECTION IS CURRENTLY ASSOCIATED WITH THIS WAVE.

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 10N14W 11N26W 9N35W 11N43W 9N50W
9N61W. BESIDES THE CONVECTION MENTIONED IN THE TROPICAL WAVE
ABOVE...SCATTERED MODERATE CONVECTION IS ALONG THE COAST OF WEST
AFRICA FROM 8N-12N E OF 16W.

$$
FORMOSA

[BigA]

Per QuikScat, looks like a bit of a surface circulation at 11 north, 24 west, though the pass is from 1900 UTC (3PM eastern, I think)

http://manati.orbit.nesdis.noaa.gov/dat ... MBds32.png

[SEASON_CANCELED]

Per QuikScat, looks like a bit of a surface circulation at 11 north, 24 west, though the pass is from 1900 UTC (3PM eastern, I think)

http://manati.orbit.nesdis.noaa.gov/dat ... MBds32.png

nice.i had to use my imaginaton at first but i think you are correct

[JonathanBelles]

Per QuikScat, looks like a bit of a surface circulation at 11 north, 24 west, though the pass is from 1900 UTC (3PM eastern, I think)

http://manati.orbit.nesdis.noaa.gov/dat ... MBds32.png

nice.i had to use my imaginaton at first but i think you are correct

I see it, in the 'third wave'.

[Meso]

The CMC being it's aggressive self, though only developing the system far west.




The NAM showing Cycloneye receiving a soaking.

[Ed Mahmoud]

No new JB post on the tropics, just a long screed about global warming (and I agree with him 100%, but I don't pay for AccuWx PPV to read political rants), but he had previously said conditions should be favorable North of the Greater Antilles, and the new Canadian has been tweaked to make it less tweaky, so who knows?

[Stormhunter27]

Ahhh, the CMC.

I was talking with Peter Boyer (he's the entire Canadian Hurricane Centre) and he was telling me that the CMC guys have attempted to tweak the GEM back a bit so that it stops turning every tropical low into a Cat 5.

Only time will tell if their tweaks work. As far as I know, they tweaked the model as it was underdeveloping temperate cyclones, but that made it go crazy on tropical lows. The new iteration of the model may be an attempt to balance the two of them out rather than going back to the original model. I don't know if the new model is going to be rolled out for this season or not, but I still wouldn't trust the CMC/GEM until I see working properly

[FireBird]

The noticeable changes in the atmosphere over the past couple weeks have definitely spelled a start to the much overdue rainy season. But with the way these waves have been flying past in the SE Caribbean, I'm not sure anything's gonna stick just yet. I'm interested in the model development and have to agree that any chance will be further North or West, but even then, I'm just not gettin' that "vibes" just yet...

[Sanibel]

Entire basin has gone tropically devoid and negative again like it flashed off. So the next pulse of favorability should be stronger.

[wxman57]

:uarrow: No new JB post on the tropics, just a long screed about global warming (and I agree with him 100%, but I don't pay for AccuWx PPV to read political rants), but he had previously said conditions should be favorable North of the Greater Antilles, and the new Canadian has been tweaked to make it less tweaky, so who knows?

See the thread that I started on the Canadian model upgrade last week.

[Ed Mahmoud]

No new JB post on the tropics, just a long screed about global warming (and I agree with him 100%, but I don't pay for AccuWx PPV to read political rants), but he had previously said conditions should be favorable North of the Greater Antilles, and the new Canadian has been tweaked to make it less tweaky, so who knows?

See the thread that I started on the Canadian model upgrade last week.

I posted on that thread the day you put it up, and even copied it to the local KHOU forum.

[cycloneye]

This is the second wave of the train (Around 30W) that is now in the Tropical Atlantic.Some convection gain in the past few hours.Lets see the next QS pass to see if what it showed yesterday (a very weak turning) shows up again or is gone.

[Ed Mahmoud]

Srain just posted this snip from HPC on the local weather forum, the cut off ("trough split") is all part of JB's plan to menace the Southeast next week.

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
1001 AM EDT THU JUL 16 2009

VALID 12Z MON JUL 20 2009 - 12Z THU JUL 23 2009

THE MODELS AND THEIR ENSEMBLES SHOW RELATIVELY GOOD LONGWAVE
AGREEMENT THROUGH THE MEDIUM RANGE PERIOD...WITH AN UNUSUALLY HIGH
AMPLITUDE UPPER HIGH/TROUGH COUPLET EXTENDING FROM THE ROCKIES TO
THE GREAT LAKES RETROGRADING SLIGHTLY AND DE-AMPLIFYING DAYS 3-7.
THE DAY-TO-DAY DETAILS REMAIN MORE UNCERTAIN HOWEVER...WITH THE
00Z ECMWF CONSIDERED LEAST RELIABLE OF THE GUIDANCE BY BREAKING
CONTINUITY WITH AN ANOMALOUSLY STRONG SHORTWAVE TROUGH INFLUENCING
THE EXTREME NORTHEAST DAY 3 AND CANADIAN MARITIMES DAYS 4/5. THE
00Z ECMWF IS ALSO ANOMALOUS WITH LITTLE OR NO PHASING OF A
SHORTWAVE TROUGH NEAR THE ALEUTIANS WITH AN UPPER LOW OVER THE
NORTHEAST PACIFIC EARLY IN THE PERIOD...RESULTING IN STRONGER
INFLUENCING FROM THE TRAILING SHORTWAVE TROUGH OVER THE PACIFIC
NORTHWEST/N. ROCKIES/N. PLAINS DAYS 3-5 THAN INDICATED BY ALL
OTHER GUIDANCE. THUS...OUR MODEL PREFERENCE IS FOR A NEARLY EVEN
BLEND OF THE 06Z GFS/GEFS MEAN ALL DAYS. ONE REMAINING UNCERTAINTY
THAT BECOMES INCREASINGLY EVIDENT DAYS 5-7 IS THE WESTWARD
EXPANSION OF THE CENTRAL ATLANTIC UPPER HIGH...WHICH THE MODELS
SUGGEST MAY BRIDGE WITH THE UPPER HIGH OVER THE
SOUTHWEST...ESSENTIALLY PINCHING OFF A PORTION OF THE EASTERN U.S.
TROUGH OVER THE DEEP SOUTH/GULF OF MEXICO/E. TEXAS. THE GFS AND
ITS ENSEMBLE MEAN SHOW THE UPPER HIGH EXPANDING INTO THE SOUTHEAST
FASTER THAN THE ECMWF...WHICH IF TRUE...WOULD SUPPORT MORE
WESTWARD DEVELOPMENT OF THE CUTOFF LOW.

[gatorcane]

Using this VIS loop, you can also see that wave on the far right-hand side of the image. As cycloneye has mentioned, convection has increased. You can also see good cyclonic turning with this wave. Let's see if it can sustain/increase or if it meets the same fate as the wave off to the west:

http://www.ssd.noaa.gov/goes/east/tatl/loop-vis.html

[Ed Mahmoud]

The databuoy South of Islip, NY has a 1 meter water temp of 21ºC.

Besides being too cool for tropical cyclone maintenance, I suspect it is cool enough to form a stable surface layer, and even if winds 1000 meters up are still ripping at hurricane force, it would be hard to mix that down.


If the Canadian is right, and I didn't even know the Canadian ran to 10 days. Wish I knew the URL for that.

[srainhoutx]

Srain just posted this snip from HPC on the local weather forum, the cut off ("trough split") is all part of JB's plan to menace the Southeast next week.

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
1001 AM EDT THU JUL 16 2009

VALID 12Z MON JUL 20 2009 - 12Z THU JUL 23 2009

THE MODELS AND THEIR ENSEMBLES SHOW RELATIVELY GOOD LONGWAVE
AGREEMENT THROUGH THE MEDIUM RANGE PERIOD...WITH AN UNUSUALLY HIGH
AMPLITUDE UPPER HIGH/TROUGH COUPLET EXTENDING FROM THE ROCKIES TO
THE GREAT LAKES RETROGRADING SLIGHTLY AND DE-AMPLIFYING DAYS 3-7.
THE DAY-TO-DAY DETAILS REMAIN MORE UNCERTAIN HOWEVER...WITH THE
00Z ECMWF CONSIDERED LEAST RELIABLE OF THE GUIDANCE BY BREAKING
CONTINUITY WITH AN ANOMALOUSLY STRONG SHORTWAVE TROUGH INFLUENCING
THE EXTREME NORTHEAST DAY 3 AND CANADIAN MARITIMES DAYS 4/5. THE
00Z ECMWF IS ALSO ANOMALOUS WITH LITTLE OR NO PHASING OF A
SHORTWAVE TROUGH NEAR THE ALEUTIANS WITH AN UPPER LOW OVER THE
NORTHEAST PACIFIC EARLY IN THE PERIOD...RESULTING IN STRONGER
INFLUENCING FROM THE TRAILING SHORTWAVE TROUGH OVER THE PACIFIC
NORTHWEST/N. ROCKIES/N. PLAINS DAYS 3-5 THAN INDICATED BY ALL
OTHER GUIDANCE. THUS...OUR MODEL PREFERENCE IS FOR A NEARLY EVEN
BLEND OF THE 06Z GFS/GEFS MEAN ALL DAYS. ONE REMAINING UNCERTAINTY
THAT BECOMES INCREASINGLY EVIDENT DAYS 5-7 IS THE WESTWARD
EXPANSION OF THE CENTRAL ATLANTIC UPPER HIGH...WHICH THE MODELS
SUGGEST MAY BRIDGE WITH THE UPPER HIGH OVER THE
SOUTHWEST...ESSENTIALLY PINCHING OFF A PORTION OF THE EASTERN U.S.
TROUGH OVER THE DEEP SOUTH/GULF OF MEXICO/E. TEXAS. THE GFS AND
ITS ENSEMBLE MEAN SHOW THE UPPER HIGH EXPANDING INTO THE SOUTHEAST
FASTER THAN THE ECMWF...WHICH IF TRUE...WOULD SUPPORT MORE
WESTWARD DEVELOPMENT OF THE CUTOFF LOW.

Glad you caught that pitch, Ed.

[Aric Dunn]

Since no one posted this...

00
AXNT20 KNHC 161042
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT THU JUL 16 2009

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1045 UTC.

...TROPICAL WAVES...
A TROPICAL WAVE IS ALONG 29W/30W S OF 15N MOVING W 10-15 KT.
RECENT SATELLITE IMAGERY DEPICTS MID-LEVEL CYCLONIC CIRCULATION
NEAR THIS WAVE. SATELLITE-DERIVED WINDS INDICATE CYCLONIC
CURVATURE IN THE FLOW WITHIN THE 800-600 MB LAYER NEAR THIS
WAVE. SCATTERED MODERATE CONVECTION IS FROM 5N-12N BETWEEN
27W-32W.

[Aric Dunn]

I would have to say the wave SSE of the Cape Verde islands is quite a bit more impressive then the one to the west and have some fairly decent low level curvature over night and into this morning with convection maintaining at least in moderation over night as well..