The hurricane season of 2010 arrives

By: Dr. Jeff Masters , 2:56 PM GMT on June 01, 2010

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The hurricane season of 2010 is upon us. With unprecedented sea surface temperatures in the Atlantic, El Niño gone and possibly transitioning to La Niña, a massive oil slick in the Gulf of Mexico, a million earthquake refugees in Haiti at the mercy of a hurricane strike, and an ever-increasing number of people living on our coasts, the arrival of this year's hurricane season comes with an unusually ominous tone. NOAA is forecasting a very active and possibly hyperactive season, and Dr. Bill Gray has said he expects "a hell of a year." However, our ability to forecast hurricane activity months in advance is limited, and we don't yet know how the large scale weather patterns like the Bermuda High will set up during the peak part of hurricane season. In particular, I very much doubt that we are in for a repeat of the unprecedented violence of the Hurricane Season of 2005, with its 28 named storms, 15 hurricanes, and 7 intense hurricanes. While sea surface temperatures are currently warmer this year than in 2005, that year featured some very unusual atmospheric circulation patterns, with a very strong ridge of high pressure over the eastern U.S., record drought in the Amazon, and very low surface pressures over the Atlantic. A repeat of 2005's weather patterns is unlikely, though I am expecting we will get at least four major hurricanes this year. An average year sees just two major hurricanes.


Figure 1. Tracks of all June tropical storms and hurricanes in the Gulf of Mexico, 1995 - 2009. Allison was a subtropical storm (coded blue). Image credit: NOAA Coastal Services Center.

The latest long-range computer model guidance suggests there's no reason to suspect that the first two weeks of this year's hurricane season will bring any unusual activity. Climatologically, June is typically the quietest month of the Atlantic hurricane season. On average, we see only one named storm every two years in June. Only one major hurricane has made landfall in June--Category 4 Hurricane Audrey of 1957, which struck the Texas/Louisiana border area on June 27 of that year, killing 550. The highest number of named storms for the month is three, which occurred in 1936 and 1968. In the fifteen years since the current active hurricane period began in 1995, there have been eleven June named storms (if we include 2008's Tropical Storm Arthur, which really formed on May 31). Five tropical storms have formed in the first half of June in that 14-year period, giving a historical 36% chance of a first-half-of-June named storm. Five June storms in the past 14 years have passed close enough to the Deepwater Horizon oil spill location to have caused significant transport had there been an oil slick on the surface.

Sea Surface Temperatures
Sea Surface Temperatures (SSTs) are at record high levels over the tropical Atlantic between Africa and Central America this year (Figure 2). As I discussed in my May 15 post, the area between 10°N and 20°N, between the coast of Africa and Central America (20°W - 80°W), is called the Main Development Region (MDR) because virtually all African waves originate in this region. These African waves account for 85% of all Atlantic major hurricanes and 60% of all named storms. When SSTs in the MDR are much above average during hurricane season, a very active season typically results (if there is no El Niño event present.) SSTs in the Main Development Region (10°N to 20°N and 20°W to 80°W) were an eye-opening 1.46°C above average during April. This is the third straight record warm month, and the warmest anomaly measured for any month--by a remarkable 0.2°C. The previous record warmest anomalies for the Atlantic MDR were set in June 2005 and March 2010, at 1.26°C. The Arctic Oscillation (AO) and its close cousin, the North Atlantic Oscillation (NAO), are largely to blame for the record SSTs. The AO and NAO are climate patterns in the North Atlantic Ocean related to fluctuations in the difference of sea-level pressure between the Icelandic Low and the Azores-Bermuda High. If the difference in sea-level pressure between Iceland and the Azores is small (negative NAO), this creates a weak Azores-Bermuda High, which reduces the trade winds circulating around the High. During December - February, we had the most negative AO/NAO since records began in 1950, and this caused trade winds between Africa and the Lesser Antilles Islands in the hurricane Main Development Region to slow to 1 - 2 m/s (2.2 - 4.5 mph) below average. Slower trade winds mean less mixing of the surface waters with cooler waters down deep, plus less evaporational cooling of the surface water. As a result, the ocean heated up significantly, relative to normal, over the winter and Spring.

However, over the past two weeks, the AO/NAO has trended close to average, and trade winds over the tropical Atlantic have increased to near normal speeds as the Bermuda-Azores High has strengthened. SST anomalies have been falling in recent weeks, and will continue to fall in the coming two weeks, based on the latest forecast from the GFS model. While I expect that record SSTs will continue into mid-June, current trends suggest that by July, SST anomalies will be close to what they were in 2005. SST anomalies in the MDR could fall below the record 2005 levels by the peak part of hurricane season, August - October. Even so, SSTs in the Caribbean this year will be plenty warm to cause an abnormal number of major hurricanes. These warm SSTs may also cause extensive damage to the coral reefs, which suffered huge die-offs from the record SSTs of 2005.

Typically, June storms only form over the Gulf of Mexico, Western Caribbean, and Gulf Stream waters just offshore Florida, where water temperatures are warmest. SSTs are 28 - 30°C in these regions, which is about 0.5 - 1.5°C above average for this time of year. June 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. African tropical waves, which serve as the instigators of about 85% of all major hurricanes, are usually too far south in June to trigger tropical storm formation. Every so often, a tropical wave coming off the coast of Africa moves far enough north to act as a seed for a June tropical storm. This was the case for Arthur of 2008 (which also had major help from the spinning remnants of the Eastern Pacific's Tropical Storm Alma). Another way to get Atlantic June storms is for a disturbed weather area in the Eastern Pacific Intertropical Convergence Zone (ITCZ) to push north into the Western Caribbean and spawn a storm there. This was the case for Tropical Storm Alberto of 2006 (which may have also had help from an African wave). SSTs are too cold in June to allow storms to develop between the coast of Africa and the Lesser Antilles Islands--there has only been once such development in the historical record--Ana of 1979.


Figure 2. Sea Surface Temperature (SST) departure from average for May 31, 2010. SSTs averaged more that 1°C above average over the entire tropical Atlantic and Gulf of Mexico. Note the large region of below average SSTs along the Equatorial Pacific off the coast of South America, signaling the possible start of an La Niña episode. Image credit: NOAA/NESDIS.

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 June 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 few weeks 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 leaves a "hole" of low shear between the two branches off the coast of North Carolina, which is where Invest 90L formed.

The jet stream is forecast to maintain this two-branch pattern over the coming ten days (Figure 3.) This means that the waters offshore of North Carolina is the most likely place for a tropical storm to form during this period, though the southwestern Caribbean will at times have shear low enough to allow tropical storm formation. The Gulf of Mexico is forecast to have wind shear too high to support a tropical storm during the first half of June. None of our reliable forecast models call for tropical storm formation over the coming 7 days, though the NOGAPS model indicates the possibility of a tropical disturbance forming off the coast of Nicaragua on Friday.


Figure 3. Wind shear forecast from the 00Z GMT June 1, 2010 run of the GFS model for June 7. Currently, the polar jet stream is bringing high wind shear to the waters offshore New England, and the subtropical jet is bringing high wind shear to the northern Caribbean. This leaves the waters off the coast of North Carolina and southern Caribbean under low shear, making these areas the most favored region for tropical storm formation over the next 7 - 10 days. 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
It's too early to concern ourselves with dry air and dust coming off the coast of Africa, since these dust outbreaks don't make it all the way to the June tropical cyclone breeding grounds in the Western Caribbean and the Gulf of Mexico. Developing storms do have to contend with dry air from Canada moving off the U.S. coast; this was a key reason why our first "Invest" of the year, 90L off the coast of South Carolina, never became a subtropical storm.

Dust expert Professor Amato Evan of the University of Virginia has posted his forecast for African dust for the 2010 hurricane season. Dr. Evan is predicting that due to plentiful rains during last year's rainy season over the Sahel region of Africa, and near average amounts of African dust observed in May 2010 and during the 2009 hurricane season, we can expect near average or moderately below average levels of dust over the tropical Atlantic during the 2010 hurricane season.

Steering currents
The forecast steering current pattern over the next two weeks is a typical one for June, with an active jet stream bringing many troughs of low pressure off the East Coast of the U.S. These troughs will be 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. 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 2009 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
Wind shear over the main breeding grounds for June tropical cyclones, the Gulf of Mexico and Western Caribbean, is expected to be high enough over the next two weeks to give us an average chance of a June named storm. I give a 30% chance of a named storm between now and June 15, and a 60% chance for the entire month of June. There is approximately a 30% chance of a June storm passing close enough to the Deepwater Horizon oil spill to cause significant transport of the oil. See my post, What a hurricane would do the Deepwater Horizon oil spill, for more information on this.

Agatha the 6th deadliest Eastern Pacific storm on record
Central America's Tropical Storm Agatha is now the 6th deadliest Eastern Pacific tropical cyclones on record. Agatha was a tropical storm for just 12 hours, making landfall Saturday on the Pacific coast of Guatemala as a 45 mph tropical storm. However, the storm brought huge amounts of rain--as much as 36 inches--to the high mountains of Guatemala. So far, flooding and landslides have killed at least 123 people in Guatemala, with 59 others missing. The storm also killed 9 in neighboring El Salvador, and 14 in Honduras.


Figure 4. Journey to the center of the Earth: a massive sinkhole 200 feet (60 meters) deep opened up in the capital, Guatemala City, after heavy rains from Tropical Storm Agatha. How are they going to fix this hole? Wow! It doesn't even look real.

Guatemala's worst flooding disaster in recent history was due to Hurricane Stan of 2005, which killed 1,513. The deadliest Eastern Pacific tropical cyclone on record for Guatemala was Hurricane Paul of 1982, which made landfall in Guatemala as a tropical depression. Flooding from Paul's rains killed 620 people in Guatemala.

Oil spill update
Light onshore winds out of the south to southwest are expected to blow over the northern Gulf of Mexico all week, resulting increased threats of oil to the Alabama and Mississippi barrier islands, according to the latest trajectory forecasts from NOAA. These persistent southwesterly winds will likely bring oil very close to the Florida Panhandle by Saturday.

Oil spill resources
My post, What a hurricane would do the Deepwater Horizon oil spill
My post Wednesday with answers to some of the common questions I get about the spill
My post on the Southwest Florida "Forbidden Zone" where surface oil will rarely go
My post on what oil might do to a hurricane
Gulf Oil Blog from the UGA Department of Marine Sciences
NOAA trajectory forecasts
Deepwater Horizon Unified Command web site
Oil Spill Academic Task Force
University of South Florida Ocean Circulation Group oil spill forecasts
ROFFS Deepwater Horizon page
Surface current forecasts from NOAA's HYCOM model
Synthetic Aperture Radar (SAR) imagery from the University of Miami

Join the "Hurricane Haven" with Dr. Jeff Masters: a new Internet radio show
Today, I'll be experimenting with a live 1-hour Internet radio show called "Hurricane Haven." The show will be aired at 4pm EDT on Tuesdays during hurricane season. Listeners will be able to call in and ask questions. Some topics I'll cover on the first show:

1) What's going on in the tropics right now
2) Preview of the coming hurricane season
3) How a hurricane might affect the oil spill
4) How the oil spill might affect a hurricane
5) New advancements in hurricane science presented at this month's AMS Conference on Hurricanes and Tropical Meteorology
6) Haiti's vulnerability to a hurricane this season

I hope you can tune in to the broadcast, which will be at http://www.wunderground.com/wxradio/wubroadcast.h tml. If not, the show will be recorded and stored as a podcast.

Portlight receives a major grant to fund U.S. disaster relief work
The Christopher and Dana Reeve Foundation has announced today that it is awarding a Quality of Life Grant in the amount of $21,500 to Portlight Strategies, Inc. The grant will fund a ready-to-deploy container specifically outfitted to serve the immediate needs of people with disabilities in the aftermath of hurricanes and other domestic natural disasters. To read more about this award, check out the Portlight blog. Congratulations, Portlight team!

Portlight continues its Haiti response
Ready or not, the rainy season is here for Haiti. Portlight has done a tremendous amount to help the Haitians get ready for the upcoming hurricane season, as detailed in the Haitian Relief Recap blog post made last week. Please visit the Portlight.org web site or the Portlight blog to learn more and to donate to Portlight's efforts in Haiti.


Figure 5. A portion of the 30,000 pounds of rice donated to Haitian earthquake victims by Portlight earlier this month, shipped via the schooner Halie and Mathew.

I'll be back Wednesday afternoon with an analysis of the new Colorado State University hurricane forecast issued by Phil Klotzbach and Bill Gray, due out on June 2.

Jeff Masters

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Hi Pat (#1211) -
Was that what Masters was refering to towards the end of the radio show?
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June 1, 2010



June 1, 2005

*Sorry about the low resolution of the image, it's the only one available for that time frame.

Member Since: September 2, 2009 Posts: 130 Comments: 21091
1222. hydrus
Quoting KEEPEROFTHEGATE:
PHET is already a MAJOR CYCLONE
I hope that Phet weakens before it hits land. The name Nargis still makes me shudder.
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I think I need to pass out some prozak.....LOL
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1219. pottery
Quoting WaterWitch11:
i hope everyone understands that by cutting the riser more oil will be released. i just can't see how they can do this. what if they are not able to cap it once it's cut? it's a nightmare and it's just the beginning. god.................................................

I dont think that a lot more flow will result. There appear to be restrictions inside the BOP.
When they increased the pressure with the mud-pump, more flow was noticed at the leaks.
It would be flowing at max all the time if there were no restrictions.
Member Since: October 24, 2005 Posts: 0 Comments: 24026
Quoting MiamiHurricanes09:
Where is it? 91L just looks like a collection of Cirrus clouds in that image.


it died from the bottom come up.
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1202 - calm down...take a deep breath...
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1216. HadesGodWyvern (Mod)
Makoto The IMD advisories are at least 6-12 hours behind in releasing statements.
Member Since: May 24, 2006 Posts: 50 Comments: 44740
your right indianrivguy. They had sheer rams and pinch rams on the BOP from what I've heard
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1214. JamesSA
Quoting WaterWitch11:
i hope everyone understands that by cutting the riser more oil will be released. i just can't see how they can do this. what if they are not able to cap it once it's cut? it's a nightmare and it's just the beginning. god.................................................

Judging from what we just saw there is going to be ALOT more oil.
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1213. Levi32
Quoting Levi32:


Ok I believe I see our problem. When talking about an air PARCEL, the air inside is not allowed to mix with the surrounding air, making its moisture content unchanged except by condensation.

However, I was talking about large-scale lifting of the air within the air column, which would cause air to cool at the DALR in the mid-level dry layer and at the MALR in the low-levels, which are hypothetically saturated.


If you want a link to back it up....here's one from Habyhints.

"METEOROLOGIST JEFF HABY

Convective instability occurs when dry mid-level air advects over very warm and moist air in the lower troposphere. Convective instability is released when dynamic lifting from the surface to the mid-levels produces a moist adiabatic lapse rate of air lifted from the lower troposphere and a dry adiabatic lapse rate from air lifted in the middle troposphere. Over time, this increases the lapse rate in the troposphere "
Member Since: November 24, 2005 Posts: 635 Comments: 26547
Quoting Weather456:
Where is it? 91L just looks like a collection of Cirrus clouds in that image.
Member Since: September 2, 2009 Posts: 130 Comments: 21091
1211. Patrap
Multiplatform Tropical Cyclone Kinetic Energy and Intensity Tropical Cyclone PHET



Multi platform Tropical Cyclone Kinetic Energy and Intensity

From the Multi platform satellite wind analysis discussed above a flight level (~ 700 hPa) Kinetic Energy is calculated within 200km of the cyclone center. The calculated KE is then categorized (0-5) so that their probability distribution is identical to the Saffir- Simpson Hurricane Intensity Scale (0-5). The KE is then plotted versus the maximum surface wind from these same wind analysis and provided every six hours. Tropical cyclones tend to grow as they weaken, but this is not always the case and large storms typically have larger values of KE and thus are more destructive when they affect land. This product allows the real-time monitoring of the potential destructive potential of a given storm and allows inter comparison with past events either produced on this web page or from actual flight level wind data. The methods for calculating and categorizing the KE as well as analyses of several past events are described in Maclay et al. (2008).

Member Since: July 3, 2005 Posts: 420 Comments: 127549
Boy, CNN and FOX are missing out on some of the best tv in history. Looks like FOX is bitching about Democrats (suprise!) and CNN has Lady Gagall.
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Double Eyewall....

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91L should be deactivated tomorrow.

But for the meantime...

AL, 91, 2010060200, , BEST, 0, 193N, 857W, 25, 1011, DB,

Member Since: September 2, 2009 Posts: 130 Comments: 21091
1207. pottery
I think we just got a close-up of the wire, above a brace or bracket close to the saw housing. Looks like the cut will be from the saw out.
Member Since: October 24, 2005 Posts: 0 Comments: 24026
To see all the equipment and a full explanation watch this technical briefing:

http://bp.concerts.com/gom/kentwellstechupdatelong053110.htm
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1205. Levi32
Quoting beell:


A lifted air parcel cools at the dry adiabatic lapse rate until it reaches LCL.
LCL is found by considering the parcel's initial relative humidity and temperature. This calculation assumes that, as it rises, the parcel's moisture content remains unchanged (that is, it does not mix with the surrounding air - a valid assumption if the lifting occurs fast enough).
Once LCL is reached, the lapse rate changes abruptly to moist adiabatic and continues to be so until the lifting stops. The moist rate has to be continually adjusted to compensate for its change with temperature. Throughout this process we continue to compare the parcels lapse rate to the environmental rate. As is the case with dry convection, the air will begin to convect freely once the temperature of the rising parcel becomes higher than the temperature of the environment**.
Overall moist air is more unstable than dry air because of the release of latent heat involved in moist convection. Since latent heating warms the rising air parcel, it is easier for it to become warmer than the environment and thus unstable.


Try this one:
Columbia University-Atmospheric Physics

I have faith in you, Levi. One day you will get it right. I would urge you to poke around a bit on this subject before you go to re-writing the laws of thermodynamics and parcel theory.


Ok I believe I see our problem. When talking about an air PARCEL, the air inside is not allowed to mix with the surrounding air, making its moisture content unchanged except by condensation.

However, I was talking about large-scale lifting of the air within the air column, which would cause air to cool at the DALR in the mid-level dry layer and at the MALR in the low-levels, which are hypothetically saturated.
Member Since: November 24, 2005 Posts: 635 Comments: 26547
Quoting msgambler:
It's not the point of being sharp. It is the force that is put on the object being cut. It's all cut through hydrolics and I don't think you could ever modify the cutters to exort enough force to crimp the pipe completely closed. There would still be a gap on the edges of the round pipe.


I'm pretty sure that's how the "shears" on the BOP work.. drive a blade across the pipe cutting it off and sealing the hole with the blade... only "this" time, the shears did not have enough azz to complete the job and here we are...
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i hope everyone understands that by cutting the riser more oil will be released. i just can't see how they can do this. what if they are not able to cap it once it's cut? it's a nightmare and it's just the beginning. god.................................................
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1201. HadesGodWyvern (Mod)
ya the IMD needs to adjust their forecast with that 21:00 PM UTC advisory. The next advisory will be a little more accurate with it stating 50-60 knots.
Member Since: May 24, 2006 Posts: 50 Comments: 44740
1200. Patrap
Tropical Cyclone PHET

Multiplatform Satellite Surface Wind Analysis 1800 UTC

Multi-Platform Tropical Cyclone Surface Wind Analysis

Currently, this product combines information from five data sources to create a mid-level (near 700 hPa) wind analysis using a variational approach described in Knaff and DeMaria (2006). The resulting mid-level winds are then adjusted to the surface applying a very simple single column approach. Over the ocean an adjustment factor is applied, which is a function of radius from the center ranging from 0.9 to 0.7, and the winds are turned 20 degrees toward low pressure. Over land, the oceanic winds are reduced by an additional 20% and turned an additional 20 degrees toward low pressure.

The five datasets currently used are the ASCAT scatterometer, which is adjusted upward to 700 hPa in the same manner as the surface winds are adjusted downward, feature track winds in the mid-levels from the operational satellite centers, 2-d flight-level winds estimated from infrared imagery (see Mueller et al 2006 ) and 2-d winds created from Advanced Microwave Sounding Unit (AMSU)- derived height fields and solving the non-linear balance equations as described in Bessho et al (2006). Past analyses also made use of the QuickSCAT scatterometer (i.e., prior to November 2009), but this satellite is no longer producing observations of surface vector winds.

Each of the input data are shown in subpanels following the analysis (i.e., storm-relative). Shown are AMSU winds, Cloud-drift/IR/WV winds, IR-proxy winds and Scatterometer winds; QuikSCAT, when available for past analyses (BLUE) and ASCAT (RED). All input data in these panels has been reduced to a 10-m land or oceanic exposure depending on the location (i.e., non-surface data has been reduced to a 10-m exposure).

How good are the wind estimates? Here is the verification based upon 2007 data . These statistics were based on 1) H*Wind data when available and 2) best track wind radii estimates from NHC. In interpreting the wind radii verification it is important to not that the zero wind radii are included in the verification, which both skews and inflates the MAE verification statistics. Note however detection is improved over climatology provided by Knaff et al. (2007).
Member Since: July 3, 2005 Posts: 420 Comments: 127549
1199. JamesSA
Quoting pottery:

I wondered about unbolting too. But then I remembered there is still a 5" drill pipe in there too!

The saw--is that rollers on the bracket? Do they rotate the saw-frame around the pipe? Or is the diamond wire going to cut through from one side?
Good question. I wondered if it rotated too.

I can see the cutting wire now in the close up... it isn't running yet.
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1198. beell
Quoting Levi32:


All true unless there is a dry capping layer in the mid-levels of the atmosphere. Then water droplets start evaporating and the rising air becomes unsaturated and rises at the dry adiabatic lapse rate again. It is not a once saturated, always saturated thing 100% of the time. Mid-level dry air messes that up.


A lifted air parcel cools at the dry adiabatic lapse rate until it reaches LCL.
LCL is found by considering the parcel's initial relative humidity and temperature. This calculation assumes that, as it rises, the parcel's moisture content remains unchanged (that is, it does not mix with the surrounding air - a valid assumption if the lifting occurs fast enough).
Once LCL is reached, the lapse rate changes abruptly to moist adiabatic and continues to be so until the lifting stops. The moist rate has to be continually adjusted to compensate for its change with temperature. Throughout this process we continue to compare the parcels lapse rate to the environmental rate. As is the case with dry convection, the air will begin to convect freely once the temperature of the rising parcel becomes higher than the temperature of the environment**.
Overall moist air is more unstable than dry air because of the release of latent heat involved in moist convection. Since latent heating warms the rising air parcel, it is easier for it to become warmer than the environment and thus unstable.


Try this one:
Columbia University-Atmospheric Physics

I have faith in you, Levi. One day you will get it right. I would urge you to poke around a bit on this subject before you go to re-writing the laws of thermodynamics and parcel theory.
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1197. Makoto1
Quoting HurricaneSwirl:


Well one positive thing is that it looks like it will be moving FAST as it makes landfall, probably preventing it from being another "Nargis".


Agreed. But... 45 knots? Really? I hope that's an old advisory.
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1196. pottery
Quoting mikatnight:


who's got the SAW schematic?

Er, um, I handed them to you...
Member Since: October 24, 2005 Posts: 0 Comments: 24026
Quoting pottery:

I wondered about unbolting too. But then I remembered there is still a 5" drill pipe in there too!

The saw--is that rollers on the bracket? Do they rotate the saw-frame around the pipe? Or is the diamond wire going to cut through from one side?


The wire saw will cut through like a "band" saw.

Talk of unbolting/bolting is Not even feasible considering:

The weight of the parts
COMPLETE lack of visibility when it's opened
The parts would misalign and jam when some bolts were off
lining up parts of this weight would be insane (you saw how it took over an hour to drop the shear onto the riser)
to make the "bolting on" work.... you would have to "bolt something on" which goes all the way to the surface
etc
etc
etc
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91E has been deactivated:

invest_DEACTIVATE_ep912010.ren
Member Since: September 2, 2009 Posts: 130 Comments: 21091
1193. Ossqss
Quoting pottery:

I wondered about unbolting too. But then I remembered there is still a 5" drill pipe in there too!

The saw--is that rollers on the bracket? Do they rotate the saw-frame around the pipe? Or is the diamond wire going to cut through from one side?



I would think it would wrap the pipe and pull (edit-as it cuts) it back through the pipe toward the cutter. But I have no idea and just wasted a spot on the blog by saying so :)
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Quoting Weather456:


ohok, yea i understand now lol.
LOL.
Member Since: September 2, 2009 Posts: 130 Comments: 21091
Quoting pottery:

I wondered about unbolting too. But then I remembered there is still a 5" drill pipe in there too!

The saw--is that rollers on the bracket? Do they rotate the saw-frame around the pipe? Or is the diamond wire going to cut through from one side?


who's got the SAW schematic?
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1190. Patrap


Ocean Heat Content & Forecast Track

Daily Oceanic Heat Content or Tropical Cyclone Heat Potential (TCHP) estimates were being provided by Gustavo Goni at the Physical Oceanography Division of the NOAA Atlantic Oceanographic and Meteorological Laboratory located in Miami, FL until July of 2008. Since that time the OHC has been provided by J. Cummings of the Naval Research Lab and is calculated from fields generated by the Naval Coupled Ocean Data Assimilation system (NCODA; Cummings 2005). The spatial grid spacing is 0.2 Latitude x 0.2 Longitude and the units of the estimates are given as kJ/cm^2. A detailed description of how the product is created, product archives and TCHP in other regions can be found at Gustavo's web discussing TCHP . A similar method is employed using the NCODA fields. Tropical cyclone forecasts, as described above, are plotted on values of ocean heat content for reference.

For tropical cyclones in favorable environmental conditions for intensification (i.e., vertical wind shear less than 15 kt, mid-level relative humidity >50 %, and warm SSTs [i.e., >28.5C])and with intensities less than 80kt, values of ocean heat content greater than 50 kJ/cm^2 have been shown to promote greater rates of intensity change.
Member Since: July 3, 2005 Posts: 420 Comments: 127549
Quoting Levi32:


Referring to the NHC not you :) lol

Why do you think I call it a monsoon trough if I disagreed.


ohok, yea i understand now lol.
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Quoting Makoto1:


It seems determined to hit as much land at as high of an intensity as possible.... Outer bands nearing the Arabian peninsula. I figured this was going to happen when that eye started forming so quickly...


Well one positive thing is that it looks like it will be moving FAST as it makes landfall, probably preventing it from being another "Nargis".
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Quoting HadesGodWyvern:


T3.5 "Severe Cyclonic Storm" Phet

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1185. Patrap
Digital Dvorak

Tropical Cyclone PHET



Digital Dvorak Intensity Estimates

Using the infrared (IR) images collected as part of the CIRA tropical cyclone IR image archive, which are displayed in an earth relative format as a product on this web page. Center positions are extrapolated using the current position and the past 12-h mean motion vector. Tropical cyclone intensity estimates can be made using two temperatures derived from the IR imagery. The first is the warmest pixel in the eye, and second is the warmest pixel on the coldest circle between 24 and 111 km from the cyclone center. Using these values a Raw T-number can be created by using the locally developed Table That expands upon the table published in Dvorak (1984). Each T-number has an intensity, in terms of maximum 1-minute sustained winds, associated with it and can be converted to an intensity.

While Raw T-numbers give an estimate of how strong a given storm is, the quantity is noisy, and because it is an instantaneous measure does not properly account for the relatively slow decay process of tropical cyclone winds. To remove the noisy nature of the Raw T-numbers time averaging is employed to produce a 6-h running mean of the raw T-numbers. This 6-h running mean is considered the T-number associated with the current intensity if the 6-h running mean is not decreasing at more than 1.5 T-numbers per day. If the 6-h running mean is decreasing very rapidly, a maximum of 1.5 T-number per day decay rate is prescribed. This final value of the 6-h running mean with a decay rule applied is considered the current intensity number or CI. The CI, as with any T-number estimate, can be converted into a intensity. However, it is important to note that THIS TECHNIQUE IS ONLY VALID FOR STORMS OF HURRICANE INTENSITY (65 kt) OR GREATER.
The image shown on this web page shows the time series of warning intensity and the Digital Dvorak estimate of intensity at the top and the time series of raw T-number estimates, the 6-h running mean, and the CI at the bottom.

Dvorak, V., 1984: Tropical cyclone intensity analysis using satellite data.NOAA Technical Report NESDIS 11, 47 pp. [Available from NOAA/NESDIS, 5200 Auth Rd. Washington DC, 20233].
Member Since: July 3, 2005 Posts: 420 Comments: 127549
Quoting Levi32:


Referring to the NHC not you :) lol

Why do you think I call it a monsoon trough if I disagreed.
Yeah 456. LOL.
Member Since: September 2, 2009 Posts: 130 Comments: 21091
1183. Makoto1
Quoting Patrap:
Tropical Cyclone PHET
Enhanced Infrared (IR) Imagery (4 km Mercator)








It seems determined to hit as much land at as high of an intensity as possible.... Outer bands nearing the Arabian peninsula. I figured this was going to happen when that eye started forming so quickly...
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1182. HadesGodWyvern (Mod)
India Meteorological Department
Tropical Cyclone Advisory Number ELEVEN
CYCLONIC STORM PHET (ARB02-2010)
2:30 AM IST June 2 2010
=======================================

At 21:00 PM UTC, Cyclonic Storm Phet over west central and adjoining east central Arabian Sea remained practically stationary and lays centered near 17.0N 62.0E, or about 1200 kms west southwest of Mumbai, 1000 kms southwest of Naliya, and 1000 kms south southwest of Karachi, Pakistan.

3 minute sustained winds near the center is 45 knots with a central pressure of 990 hPa. The state of the sea is high to very high around the system's center.

Satellite imagery indicates central dense overcast pattern. The Dvorak intensity of the system is T3.0. Associated broken intense to very intense convection observed over the area between 12.5N to 19.0N and 56.0 to 64.0E. The lowest cloud top temperature due to convection is around -70 to -80C in association with the system.

Vertical wind shear of horizontal wind over the region is between 5-15 knots. The system lies to the south of tropospheric ridge, which roughly runs along 20.0N over the region. The relatively vorticity at 850 HPA level and upper level divergence are favorable for intensification.

The current environmental conditions and numerical weather prediction models suggest that the system would intensify into a severe cyclonic storm and move slowly in a north northwesterly/northerly direction for the next 24 hours and then recurve northeastward towards Gujarat and adjoining Pakistan coast under the influence of the approaching trough in mid latitude westerlies at 500 HPA level. Squally winds with speed reaching 30-35 knots gusting to 35 knots would commence along and off Oman coast as a peripheral affect of the system from Wednesday afternoon.

Forecast and Intensity
==========================
9 HRS: 18.0N 62.0E - 45 knots (Cyclonic Storm)
21 HRS: 19.0N 62.5E - 60 knots (Severe Cyclonic Storm)
39 HRS: 21.0N 64.0E - 70 knots (Very Severe Cyclonic Storm)
63 HRS: 23.0N 68.0E - 75 knots (Very Severe Cyclonic Storm)
Member Since: May 24, 2006 Posts: 50 Comments: 44740
Quoting Levi32:


He means stupid on the part of the NHC. Not you lol.
Yeah. LOL.
Member Since: September 2, 2009 Posts: 130 Comments: 21091
1180. xcool



NICE..


Member Since: September 26, 2009 Posts: 2 Comments: 15620
1179. Levi32
Quoting Weather456:


it is not stupid, maybe not presented in the perfect way but i know what i mean.


Referring to the NHC not you :) lol

Why do you think I call it a monsoon trough if I disagreed.
Member Since: November 24, 2005 Posts: 635 Comments: 26547
1178. Ossqss
This being the first time I have looked at this stuff on the ROV feed, what is the electric motor supposed to do that appears to be right under the primary connection? Is that a gear driven shut off? Just sayin, could that not manually be driven if it is such? I know, to easy when watching it on a PC.....
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Quoting Levi32:


It is.


it is not stupid, maybe not presented in the perfect way but i know what i mean.
Member Since: Posts: Comments:
Quoting Weather456:



another time i will explain what i mean.
Ok. You can Wumail me at any time.
Member Since: September 2, 2009 Posts: 130 Comments: 21091
1175. Levi32
Quoting Weather456:



another time i will explain what i mean.


He means stupid on the part of the NHC. Not you lol.
Member Since: November 24, 2005 Posts: 635 Comments: 26547
1174. Patrap
Tropical Cyclone PHET



Multi platform Tropical Cyclone MSLP and Maximum Winds

Minimum Sea Level Pressure is calculated directly from the azimuthally averaged gradient level tangential winds produced by the multi platform tropical cyclone wind analysis. The circular domain for the numerical integration has a 600km radius. The pressure deficit resulting from the integration is then added to an environmental pressure. The environmental pressure (Penv) is interpolated from NCEP analyses in a circle 600 km from the cyclone center. The maximum surface winds produced by the analysis are also shown.
Member Since: July 3, 2005 Posts: 420 Comments: 127549

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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.