July hurricane outlook

By: Dr. Jeff Masters , 7:26 PM GMT on July 02, 2009

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Atlantic tropical cyclone activity typically picks up a bit during the first half of July. Since the current active hurricane period began in 1995, seven of 14 years (50%) have had a named storm form during the first half of July. The busiest first half of July occurred in 2005, when three hurricanes formed. These included Hurricane Dennis and Hurricane Emily--the strongest hurricanes ever observed so early in the season. As seen in Figure 1, most of the early July activity occurs in the Gulf of Mexico, Western Caribbean, and Carolina waters. However, a few long-track "Cape Verdes" hurricanes begin to occur. These are spawned by tropical waves that come off the coast of Africa. Tropical waves serve as the instigators of about 85% of all major hurricanes. Last year's Hurricane Bertha was one such rare early July Cape Verdes hurricane. Bertha's 120 mph winds made it the sixth strongest early-season Atlantic hurricane on record. Bertha also set the record for farthest east formation as a tropical storm, hurricane, and major hurricane, so early in the season.


Figure 1. Tracks of all tropical storms and hurricanes 1851 - 2006 that formed July 1-15. North Carolina and the Gulf of Mexico coast from the Florida Panhandle to Texas are the preferred strike locations. Oddly, the Florida Peninsula has been struck by only two storms that formed in the first half of July.

Sea Surface Temperatures
Sea Surface Temperatures (SST) anomalies have warmed slightly over the past two weeks, but are close to average over the tropical Atlantic between Africa and Central America (Figure 2). These are the are the coolest SST anomalies we've seen since 1994. The strength of the Azores-Bermuda high has been near average over the past two weeks, driving near-average trade winds. Stronger-than-average trade winds were observed through most of the period November 2008 - May 2009, which helped cool the tropical Atlantic substantially. Strong winds mix up colder water from the depths and cause greater evaporative cooling. The latest 2-week run of the GFS model predicts continued average-strength trade winds through mid-July, so SSTs should remain near average during this period.

Typically, July tropical storms form over the Gulf of Mexico, Western Caribbean, and Gulf Stream waters just offshore Florida. SSTs are about 1.0°C above average for this time of year in the Gulf of Mexico, but near average elsewhere. July storms typically form when a cold front moves off the U.S. coast and stalls out, with the old frontal boundary serving as a focal point for development of a tropical disturbance. There will be one or two fronts moving off the U.S. coast over the next two weeks, and we will need to watch these for development. Wind shear is too high and SSTs are usually too cold in July to allow African tropical waves to develop into tropical storms. African tropical waves serve as the instigators of about 85% of all major hurricanes,

Figure 2. Sea Surface Temperature (SST) departure from average for July 2, 2009. SSTs were near average over the tropical Atlantic's Main Development region for hurricanes, from Africa to Central America between 10° and 20° North Latitude. Note the large region of above average SSTs along the Equatorial Pacific off the coast of South America, the hallmark of a developing El Niño episode. Image credit: NOAA/NESDIS

El Niño
El Niño conditions continue to amplify over the tropical Eastern Pacific. Ocean temperatures there rose 0.5°C over the past two weeks, and are now 0.45°C above the threshold for El Niño, according to the Australian Bureau of Meteorology (Figure 3). NOAA's Climate Prediction Center issued an El Niño Watch in early June, saying "that conditions are favorable for a transition from neutral to El Niño conditions during June - August 2009". The pattern of changes in surface winds, upper-level winds, sea surface temperatures, and deeper water heat content are all consistent with what has been observed during previous developing El Niños, and latest set of mid-June runs of the El Niño computer models are almost universally calling for El Niño conditions to become well-established for the peak months of hurricane season, August - October. It is likely that Atlantic hurricane activity will be suppressed in 2009 due to the strong upper-level winds and resulting wind shear an El Niño event usually brings to the tropical Atlantic.


Figure 3. Sea Surface Temperature (SST) departure from average for the the equatorial Eastern Pacific (the area 5°N - 5°S, 120°W - 170°W, also called the "Niña 3.4 region"). El Niño conditions exist when the SST in this region rises 0.5°C above average. As of June 28, 2009, SSTs in the Niño 3.4 region had risen to 0.95°C above average. To be considered an "El Niño episode", El Niño conditions must occur for five consecutive months, using 3-month averages. Image credit: Australian Bureau of Meteorology.

Wind shear
Wind shear is usually defined as the difference in wind between 200 mb (roughly 40,000 foot altitude) and 850 mb (roughly 5,000 foot altitude). In most circumstances, wind shear above 20 knots will act to inhibit tropical storm formation. Wind shear below 12 knots is very conducive for tropical storm formation. High wind shear acts to tear a storm apart. The jet stream's band of strong high-altitude winds is the main source of wind shear in July over the Atlantic hurricane breeding grounds, since the jet is very active and located quite far south this time of year.

The jet stream over the past two months has been locked into a pattern where a southern branch (the subtropical jet stream) brings high wind shear over the Caribbean, and a northern branch (the polar jet stream) brings high wind shear offshore of New England. This often leaves a "hole" of low shear between the two branches off the coast of North Carolina, which is where Tropical Depression One formed at the end of May.

The jet stream is forecast (Figure 4) to maintain this two-branch pattern over the coming two weeks. This means that the waters offshore of the Carolinas are the most likely place for a tropical storm to form during this period.


Figure 4. Wind shear in m/s between 200 mb and 850 mb, as forecast by the 06Z July 02, 2009 run of the GFS model. The position and strength of the subtropical jet stream is forecast to change little over the next two weeks, and this jet will bring high wind shear to the Caribbean and Gulf of Mexico into mid-July. There will at times be a region of low shear between the polar jet (northern set of arrows on the plots) and the subtropical jet, allowing for possible tropical development off the coast of North Carolina. Wind speeds are given in m/s; multiply by two to get a rough conversion to knots. Thus, the red regions of low shear range from 0 - 16 knots.

Dry air and African dust
June and July are the peak months for dust coming off the coast of Africa, and the Saharan dust storms have been quite active over the past month. Expect dust from Africa to be a major deterrent to any storms that try to form between Africa and the Lesser Antilles Islands in July.

Steering currents
The steering current pattern over the past few weeks has not changed much, and is typical for June and July. We have an active jet stream bringing many troughs of low pressure off the East Coast of the U.S. These troughs are frequent enough and strong enough to recurve any tropical storms or hurricanes that might penetrate north of the Caribbean Sea. Steering current patterns are predictable only about 3 - 5 days in the future, although we can make very general forecasts about the pattern as much as two weeks in advance. At present, it appears that the coming two weeks will maintain the typical July pattern, bringing many troughs of low pressure off the East Coast capable of recurving any July storms that might form. There is no telling what might happen during the peak months of August, September, and October--we might be in for a repeat of the favorable 2006 steering current pattern that recurved every storm out to sea--or the unfavorable 2008 pattern, that steered Ike and Gustav into the Gulf of Mexico.

Summary
Recent history suggests a 50% chance of a named storm occurring in the first half of July. Given that none of the computer models are forecasting tropical storm formation in the coming seven days, and SST and wind shear patterns look pretty average, I'll go with a 20% chance of a named storm forming during the first half of July.

Vote for Mike Theiss as an Antarctica blogger
Extreme weather photographer Mike Theiss, who wrote our Ultimate Chase photography blog for two years until a new job took him to South America, wants your help. He's entering a Quark Expeditions competition to receive an expense-paid 2-week trip to Antarctica, where he will do some intensive photography and blogging. In order to go, he needs the votes to show that he's a popular blogger. So, if you liked his posts while he was blogging for wunderground, and want to see him blog for wunderground during this potential Antarctica voyage, go to http://www.blogyourwaytoantarctica.com/blogs/view /220 and cast a vote. It takes about 3 minutes navigate through the registration and voting process. Mike will be back chasing hurricanes this August, and has promised to post his excellent storm photos on wunderground should we help him secure the Antarctica gig.

Have a great holiday weekend, and I'll be back Monday with a new post.

Jeff Masters

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2004 Virtual Reality

938. Storm 7:36 PM AST on July 05, 2004

The season is over, what a dud.

1024. WU88 9:36 AM AST on July 21, 2004

I don't think this season will every start.

138. W456 10:36 AM AST on July 28, 2004

El Nino will keep the season quiet, nothing to worry about.

Dennis
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1945. KEEPEROFTHEGATE (Mod)
Quoting Tazmanian:
i wonuder if we evere had a hurricane season befor with no name storm or 1 name storm
ya 1914 only one storm
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WOW Levi. I understood that a lot more than I understood this

Thanks
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Quoting StSimonsIslandGAGuy:
19% of the way through hurricane season and all's well!


I used to think that's how the percentage was calculated myself until recently, actually by the end of July we're through about 15% of the actual season in terms of named storms, June accounts for about 6% and July 9% of named storms so in reality we're rough about only 7% through the Season, confusing no doubt but that's how the experts do it from what I understand, for example at the end of Oct only 5% of the season is left , because Nov. only accounts for 5% of named storms as averaged by the Season.
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1942. KEEPEROFTHEGATE (Mod)
AOI
MARK
16.0N/71.1W

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1941. Patrap
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i wonuder if we evere had a hurricane season befor with no name storm or 1 name storm
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1939. Levi32
Quoting Weather456:


21 this month


Happy early birthday =)
Member Since: November 24, 2005 Posts: 635 Comments: 26547
1938. Levi32
Quoting RMM34667:


I'd love to hear more information on

New form of El Nino may increase Atlantic storms

considering this article is saying In 2004 an El Nino was developing, causing forecasters to expect fewer Atlantic hurricanes.

But instead it turned out to be one of the Modoki years. There were 15 named storms, including six major hurricanes. Overall activity was nearly two and a half times the long-term average, resulting in more than 3,100 deaths in the region including 60 in the United States. There was record property damage in the United States.


I would love to here from the great minds on this site what that might mean.


I've read about it, and it makes sense. If the center of the warming, and hence the upward motion, is further west in the Pacific, then everything else shifts west with it. That puts less wind shear and warmer SSTs over the tropical Atlantic and overall conditions become more favorable.
Member Since: November 24, 2005 Posts: 635 Comments: 26547
Quoting Tazmanian:



my new hurricane forcast calls for no name storms and no hurricane this year
Sounds good to me. I second the motion.
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Quoting Tazmanian:
my new hurricane forcast calls for 1 name storm and no hurricaes this year


My forecast was 2 named storms and since we already had 90L and 92L, I've met my quota. So I'm here waiting for June 1 2010 for my new quota.
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Looking better now than it did a few hours ago.
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Quoting Acemmett90:

to early to call the season a falure lol is bordom getting to you taz



my new hurricane forcast calls for no name storms and no hurricane this year
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Quoting Weather456:


21 this month
When ?
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Quoting stormwatcherCI:
I knew you were young but didn't figure you for that young. Just 21 ?


21 this month
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my new hurricane forcast calls for 1 name storm and no hurricaes this year
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1929. Levi32
Quoting beell:
1893.
All the tropical waves are bound for the east Pacific and Central America right now

The GFS would tend to agree with you, Levi. Both the 12Z and 18Z flirt with it over the BOC at around 84 hours give or take a frame or two-the timing seems correct anyway. At 20N 95W. A trend in the model to build the ridge up into the western GOM. Still-not a slam dunk for due west depending on the low level ridge :) Certainly dealing with a more southern e to w edge to the ridge for sure.

18Z GFS 850mb at 84 hours.


Yeah Beell. It's still possible we get a surge of moisture into the western Caribbean or BOC, but with most of the heat focused in the eastern Pacific chances are lower for development in those areas. Pretty much the tropical Atlantic south of 20N is dead right now lol. My eyes are on the SE US coast for the next 10 days.
Member Since: November 24, 2005 Posts: 635 Comments: 26547
Quoting Weather456:


Back then (1998) I was 10 and all I had was a black and white tracking map, black and white satellite images and the Weather Channel. I knew little of hurricanes and tropical waves but enough to identified them. I don't think the TPC TWD go that far back and even if, I had no access to the internet till about 2002.
I knew you were young but didn't figure you for that young. Just 21 ?
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I think we are getting a bit too caught up in El Nino. Do not forget, 2004 had a weak El Nino and had a lot of storms overall, and some storms in the Caribbean as well. This year also has a weak El Nino, and we will see what happens numbers-wise as the season progresses.
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Quoting hurricaneseason2006:


What about the TWD?


Back then (1998) I was 10 and all I had was a black and white tracking map, black and white satellite images and the Weather Channel. I knew little of hurricanes and tropical waves but enough to identified them. I don't think the TPC TWD go that far back and even if, I had no access to the internet till about 2002.

If it really wasn't for Georges I would have not continued.
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Quoting extreme236:


There isnt much more to say right now about el nino.


I'd love to hear more information on

New form of El Nino may increase Atlantic storms

considering this article is saying In 2004 an El Nino was developing, causing forecasters to expect fewer Atlantic hurricanes.

But instead it turned out to be one of the Modoki years. There were 15 named storms, including six major hurricanes. Overall activity was nearly two and a half times the long-term average, resulting in more than 3,100 deaths in the region including 60 in the United States. There was record property damage in the United States.


I would love to here from the great minds on this site what that might mean.
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1923. Levi32
Quoting Orcasystems:
Levi, your buddy hasn't burped for quite sometime... semi dormant again?


Down to code Yellow now. I've heard the lava dome is still unstable but it sure seems quiet. Hopefully she slowly goes back to sleep and we won't hear from her again for another 10 years.
Member Since: November 24, 2005 Posts: 635 Comments: 26547
Pressure has been falling for the last 6 hrs. Conditions at 42058 as of
2250 GMT on 07/05/2009:
Unit of Measure: Time Zone:

Click on the graph icon in the table below to see a time series plot of the last five days of that observation.
5-day plot - Wind Direction Wind Direction (WDIR): ENE ( 70 deg true )
5-day plot - Wind Speed Wind Speed (WSPD): 23.3 kts
5-day plot - Wind Gust Wind Gust (GST): 27.2 kts
5-day plot - Wave Height Wave Height (WVHT): 6.6 ft
5-day plot - Dominant Wave Period Dominant Wave Period (DPD): 7 sec
5-day plot - Average Period Average Period (APD): 5.1 sec
5-day plot - Mean Wave Direction Mean Wave Direction (MWD): E ( 93 deg true )
5-day plot - Atmospheric Pressure Atmospheric Pressure (PRES): 29.86 in
5-day plot - Pressure Tendency Pressure Tendency (PTDY): -0.02 in ( Falling )
5-day plot - Air Temperature Air Temperature (ATMP): 83.8 °F
5-day plot - Water Temperature Water Temperature (WTMP): 82.8 °F
5-day plot - Dew Point Dew Point (DEWP): 76.3 °F
5-day plot - Heat Index Heat Index (HEAT): 92.8 °F
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1921. Levi32
Ensemble 500mb height anomalies showing where all the energy is getting directed, towards the east Pacific where all the upward motion is. In this kind of a pattern with El Nino a lot of tropical waves in the Caribbean tend to continue west across Central America and pop out the other side in the Pacific where they have better conditions for development.

Member Since: November 24, 2005 Posts: 635 Comments: 26547
1920. beell
1893.
All the tropical waves are bound for the east Pacific and Central America right now

The GFS would tend to agree with you, Levi. Both the 12Z and 18Z flirt with it over the BOC at around 84 hours give or take a frame or two-the timing seems correct anyway. At 20N 95W. A trend in the model to build the ridge up into the western GOM. Still-not a slam dunk for due west depending on the low level ridge :) Certainly dealing with a more southern e to w edge to the ridge for sure.

18Z GFS 850mb at 84 hours.
Member Since: September 11, 2007 Posts: 141 Comments: 16213
Levi, your buddy hasn't burped for quite sometime... semi dormant again?
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Quoting all4hurricanes:

Hurricane Dean I think was moving at 20kts when it developed. I know it was moving around 20kts when it became a cat 5.


Correct, I think it crossed about 75-100miles South of Grand Cayman, we got some nasty weather from it, especially high seas on the South side, I think its average forward speed was around 20mph all the way from the East Atlantic til landfall along Belize/Mexican border.
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Forward speed of 20-24 kt. With low vertical shear and well-established upper-level outflow, the depression strengthened into Tropical Storm Charley early on 10 August. Fairly steady strengthening continued while the storm moved into the central Caribbean Sea, and when Charley approached Jamaica on 11 August, it became a hurricane.
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1915. Levi32
Quoting Weather456:
Levi, while your description of conditions in the Caribbean are true regarding the tropical wave and Colombian low, and high, etc. It happens every year. This is near the long-term average since we normally get fast moving tropical waves in the Caribbean during June and July. I've seen this too many times, even in El Nino years.

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT FRI 04 JUL 2003

TROPICAL WAVE PREVIOUSLY ALONG 76W/77W IS NOW ALONG 78W SOUTH OF
19N MOVING WEST 15-20 KT. NUMEROUS STRONG CONVECTION IS LOCATED
WITHIN 60 NM OF THE LINE 18N79W 10N83W. SCATTERED MODERATE TO
STRONG CONVECTION IS LOCATED FROM 6N-11N BETWEEN 75W-77W... AND
FROM 10N-12N BETWEEN 77W-80W.


Ok well I trust you know about the long-term average better than I do, especially since you live down there. I guess we'll see if the pattern continues into August. It will be interesting to see how many storms we get in the Caribbean this year.
Member Since: November 24, 2005 Posts: 635 Comments: 26547
Quoting all4hurricanes:

Hurricane Dean I think was moving at 20kts when it developed. I know it was moving around 20kts when it became a cat 5.


Yeah, it was moving at 21 mph according to the first advisory. I posted it above.
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Quoting eyewall99:
15-20kts is not unusual...I have seen plenty of waves develop with that forward speed. Grasping for topics ehhh?

Hurricane Dean I think was moving at 20kts when it developed. I know it was moving around 20kts when it became a cat 5.
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Levi, while your description of conditions in the Caribbean are true regarding the tropical wave and Colombian low, and high, etc. It happens every year. This is near the long-term average since we normally get fast moving tropical waves in the Caribbean during June and July. I've seen this too many times, even in El Nino years. There was a particularly fast moving wave in 1998, but those time we used to measure speed by longitude per day.

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT FRI 04 JUL 2003

TROPICAL WAVE PREVIOUSLY ALONG 76W/77W IS NOW ALONG 78W SOUTH OF
19N MOVING WEST 15-20 KT. NUMEROUS STRONG CONVECTION IS LOCATED
WITHIN 60 NM OF THE LINE 18N79W 10N83W. SCATTERED MODERATE TO
STRONG CONVECTION IS LOCATED FROM 6N-11N BETWEEN 75W-77W... AND
FROM 10N-12N BETWEEN 77W-80W.
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Blog Update
Reflector site for those at work, which now also includes Weather456, daily updates


AOI

AOI
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1910. KEEPEROFTHEGATE (Mod)
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1909. Levi32
Quoting eyewall99:
15-20kts is not unusual...I have seen plenty of waves develop with that forward speed. Grasping for topics ehhh?


Lol yeah it's pretty boring. I don't know I have only been frequently tracking storms since 2004. I just know what the average speed of a wave is and I've seen plenty that had issues because of a forward speed greater than 15kts. I guess we'll see.
Member Since: November 24, 2005 Posts: 635 Comments: 26547
I looked and Hurricane Dean became a tropical depression moving at 21 mph

ZCZC MIATCPAT4 ALL
TTAA00 KNHC DDHHMM
BULLETIN
TROPICAL DEPRESSION FOUR ADVISORY NUMBER 1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042007
1100 AM EDT MON AUG 13 2007

...FOURTH DEPRESSION OF THE SEASON FORMS IN THE FAR EASTERN
ATLANTIC...

AT 1100 AM EDT...1500Z...THE CENTER OF TROPICAL DEPRESSION FOUR WAS
LOCATED NEAR LATITUDE 12.0 NORTH...LONGITUDE 31.6 WEST OR ABOUT 520
MILES...840 KM...WEST-SOUTHWEST OF THE SOUTHERNMOST CAPE VERDE
ISLANDS AND ABOUT 2000 MILES...3220 KM...EAST OF THE LESSER
ANTILLES.

THE DEPRESSION IS MOVING TOWARD THE WEST NEAR 21 MPH...AND THIS
GENERAL MOTION IS EXPECTED TO CONTINUE DURING THE NEXT 24 HOURS.
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15-20kts is not unusual...I have seen plenty of waves develop with that forward speed. Grasping for topics ehhh?
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1906. Levi32
Quoting Weather456:


I agree right now, but as to for the entire season, is to be seen.


I agree, it would just make sense to see this trend continue with El Nino strengthening the Columbian Heat Low. They may slacken if the subtropical ridge moves north a bit and gives some room. Right now it's position to the south is causing a bad pressure gradient. We'll see what happens if it moves later on.
Member Since: November 24, 2005 Posts: 635 Comments: 26547
1905. Patrap
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1904. Levi32
Quoting Weather456:
Levi,

Trades were also higher 2005




2005



2009



Well I don't know if they slowed down later. Dennis and Emily made it in July 05 because they formed east of the Caribbean. Already-developed tropical systems can handle high trades but it's hard to get a tropical wave to develop into a system from within them.
Member Since: November 24, 2005 Posts: 635 Comments: 26547
Quoting Levi32:


I'd like to see it if you have an image showing the trade wind speed relative to normal. Right now they're too fast. The Columbian Low is stronger than normal right now and the surface ridge is squashed further south than normal, which is also pushing the wave train to the south. On the ECMWF when you see yellows like that in the Caribbean that's bad news for tropical waves.


I agree right now, but as to for the entire season, is to be seen.
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1902. Levi32
Quoting Levi32:


I'd like to see it if you have an image showing the trade wind speed relative to normal. Right now they're too fast. The Columbian Low is stronger than normal right now and the surface ridge is squashed further south than normal, which is also pushing the wave train to the south. On the ECMWF when you see yellows like that in the Caribbean that's bad news for tropical waves.


...TROPICAL WAVES...

A TROPICAL WAVE IS ALONG 25W S OF 16N MOVING W 15-20 KT. AN
INVERTED-V LOW CLOUD BAND IS NOTED AND THE SSMI TOTAL
PRECIPITABLE WATER IMAGERY SHOWS A MOISTURE PLUME. CONVECTION IS
CONFINED TO THE ITCZ. ISOLATED MODERATE CONVECTION IS FROM
9N-12N BETWEEN 21W-28W.

A TROPICAL WAVE IS ALONG 64W S OF 20N MOVING W 15-20 KT. A WELL
DEFINED INVERTED-V LOW CLOUD BAND IS NOTED AND THE SSMI TOTAL
PRECIPITABLE WATER IMAGERY ALSO SHOWS A LARGE MOISTURE PLUME.
SCATTERED MODERATE CONVECTION IS OVER THE E CARIBBEAN FROM
10N-20N BETWEEN 60W-70W.

A TROPICAL WAVE IS ALONG 78W S OF 20N MOVING W 20 KT. THE SSMI
TOTAL PRECIPITABLE WATER IMAGERY SHOWS A LARGE AREA OF MOISTURE
OVER THE W CARIBBEAN AND CENTRAL AMERICA. CLUSTERS OF SCATTERED
MODERATE TO ISOLATED STRONG CONVECTION ARE FROM 9N-13N BETWEEN
76W-85W.

Look at how fast all the tropical waves are moving. That's too fast to think about much development. The average speed is 10-15 knots, and if they move faster than that it's very hard to amplify and get surface convergence going.
Member Since: November 24, 2005 Posts: 635 Comments: 26547
Levi,

Trades were also higher 2005




2005



2009

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REMEINDER for all Floridians!
Space Shuttle Endeavour will launch this upcoming Saturday @ 7:39 PM,
Going to be 6 miles from the pad during liftoff.
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1899. Levi32
Quoting Weather456:


I don't think that would be the pattern of the entire hurricane season, since trades across the Caribbean is currently near to below average due to a continuing negative NAO.


I'd like to see it if you have an image showing the trade wind speed relative to normal. Right now they're too fast. The Columbian Low is stronger than normal right now and the surface ridge is squashed further south than normal, which is also pushing the wave train to the south. On the ECMWF when you see yellows like that in the Caribbean that's bad news for tropical waves.
Member Since: November 24, 2005 Posts: 635 Comments: 26547
Quoting stormpetrol:


Correct, I remember that, I knew Ivan was going hit Grand Cayman too,remember Ivan was forcasted hit Cayman Brac and Paloma Grand Cayman, vice versa happened, I knew after Paloma wobbled late that evening that the Brac was going to get a direct hit and we were going to be spared the brunt, I even posted my thoughts here regarding Paloma.
When Ivan was halfway across the Atl I told my co-workers I had a bad feeling about it. I told them it was going to hit GC and hit us hard. They called me a fool. Now they all ask my opinion about whatever makes it into the Caribbean.. I guess I am not such a fool after all.
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Quoting Levi32:


Sheared right now. Convection being enhanced by the TUTT not by any particular effort by the wave itself. The trade winds are too strong in the Caribbean right now to let any tropical waves slow down and amplify. Strong easterlies in there ruin convergence. All the tropical waves are bound for the east Pacific and Central America right now. This is the kind of pattern we'll likely see for most of the hurricane season.


I don't think that would be the pattern of the entire hurricane season, since trades across the Caribbean is currently near to below average due to a continuing negative NAO. Probably the number 1 reason disrupting the formation of circulation is vertical shear.
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.