Pakistan's Katrina; 94L could develop in Gulf of Mexico

By: Dr. Jeff Masters , 3:23 PM GMT on August 10, 2010

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The monsoon season of 2010 continues to generate havoc in Asia, as lingering rains from the latest monsoon low continue to affect hard-hit Pakistan, China, and India. At least 702 are now reported dead and 1,042 are missing in China's Gansu province, due to torrential monsoon rains that triggered a deadly landslide and extreme flooding on Sunday. At least 137 died in floods and landslides in the neighboring Indian state of Kashmir over the weekend, with 500 people missing. Monsoon flooding and landslides have also killed at least 65 people in Afghanistan in the past two weeks. But no country has suffered more than Pakistan, where monsoon floods have destroyed huge portions of the nation's infrastructure and killed at least 1600 people. The number of people affected or needing assistance has been estimated to be as high as 13 million people--8% of the nation's population. The disaster is the worst natural disaster in Pakistan's history, and is rightfully being called "Pakistan's Katrina."


Figure 1. The heavy thunderstorms of a monsoon depression lie over northwestern Pakistan near Islamabad in this visible satellite image taken by NASA's MODIS instrument on July 29, 2010. Image credit: NASA.

Monsoons: a primer
In summer, the sun warms up land areas more strongly than ocean areas. This occurs because wind and ocean turbulence mix the ocean's absorbed heat into a "mixed layer" approximately 50 meters deep, whereas on land, the sun's heat penetrates at a slow rate to a limited depth. Furthermore, due to its molecular properties, water has the ability to absorb more heat than the solid materials that make up land. As a result of this summertime differential heating of land and ocean, a low pressure region featuring rising air develops over land areas. Moisture-laden ocean winds blow towards the low pressure region and are drawn upwards once over land. The rising air expands and cools, condensing its moisture into some of the heaviest rains on Earth--the monsoon. Monsoons operate via the same principle as the familiar summer afternoon sea breeze, but on a grand scale. Each summer, monsoons affect every continent on Earth except Antarctica, and are responsible for life-giving rains that sustain the lives of billions of people. In India, home for over 1.1 billion people, the monsoon provides 80% of the annual rainfall. However, monsoons have their dark side as well--hundreds of people in India and surrounding nations die in an average year in floods and landslides triggered by heavy monsoon rains. The most deadly flooding events usually come from monsoon depressions (also known as monsoon lows.) A monsoon depression is similar to (but larger than) a tropical depression. Both are spinning storms hundreds of kilometers in diameter with sustained winds of 50 - 55 kph (30 - 35 mph), nearly calm winds at their center, and generate very heavy rains. Each summer, approximately 6 - 7 monsoon depressions form over the Bay of Bengal and track westwards across India. Four monsoon depressions originated in the Bay of Bengal in the El Niño-weakened monsoon season of 2009. This year's first monsoon depression formed on July 24, crossed over India, and reached Pakistan on July 27. The rains increased in intensity over the next two days, peaking on July 29 and 30, when a low pressure system that moved across Pakistan from the west enhanced rainfall from the monsoon depression. Over the 3-day period July 28 - 30, torrential rains in excess of 8 inches (203 mm) fell in many regions of northwest Pakistan Rainfall amounts at two stations in the catchment basins of the Jhelum River and Indus River reached 19.49" (495 mm) for the month of July, and 7.56" (192 mm) fell in a single day, July 30, at Tarbela. A second monsoon depression arrived in Pakistan on August 3, and has brought additional heavy rains.

Are the this year's monsoon floods due to global warming?
No single weather event can be attributed to climate change, but a warming climate does load the dice in favor of heavier extreme precipitation events. This occurs because more water vapor can evaporate into a warmer atmosphere, increasing the chances of record heavy downpours. In a study published in Science in 2006, Goswami et al. found that the level of heavy rainfall activity in the monsoon over India had more than doubled in the 50 years since the 1950s, leading to an increased disaster potential from heavy flooding. Moderate and weak rain events decreased over the past 50 years, leaving the total amount of rain deposited by the monsoon roughly constant. The authors commented, "These findings are in tune with model projections and some observations that indicate an increase in heavy rain events and a decrease in weak events under global warming scenarios." We should expect to see an increased number of disastrous monsoon floods in coming decades if the climate continues to warm as expected. Since the population continues to increase at a rapid rate in the region, death tolls from monsoon flooding disasters are likely to climb dramatically in coming decades.

References
Goswami, et al., 2006, " Increasing Trend of Extreme Rain Events Over India in a Warming Environment", Science, 1 December 2006:Vol. 314. no. 5804, pp. 1442 - 1445 DOI: 10.1126/science.1132027

Dave's Landslide blog has some great discussions of the flooding and destruction wrought by the terrible monsoon rains this year in Pakistan, India, Afghanistan, and China.

Donations urgently needed
The massive humanitarian crisis in Pakistan requires a huge response by the international community. Wunderblogger Dr. Ricky Rood, author of our Climate Change Blog, has a friend working in Pakistan who underscored the desperate situation there:

This is the worst natural disaster in the history of Pakistan in terms of number of people and area affected. Although not as many people have been killed as in the 2005 earthquake, we have already nearly 900,000 displaced persons thus far just in Khyber Pakhtunkhwa. Crops are destroyed; shops, hotels, and other business have simply been swept away in Swat, which had just this year been cleared of Taliban and was on the way to recovery; and districts closer to Peshawar and parts of Peshawar district are still, or perhaps again after yesterday/today, under water. After the immediate emergency response, it will be years of rebuilding to replace what has been lost and to start to develop again. I know you have the power to control the weather, so if you cold give us a week or two without more rain at least we could keep the helicopters flying and give people a chance to go to their homes, recover what might still be there, set up tents if we can get enough to them, and start to clean up."

She gave the following recommendations for charities that do work in the flood-ravaged zone, and are effective at getting aid to those who need it the most:

Doctors Without Borders

The International Red Cross

MERLIN medical relief charity

The mobile giving service mGive allows one to text the word "SWAT" to 50555. The text will result in a $10 donation to the UN Refugee Agency (UNHCR) Pakistan Flood Relief Effort.

She mentioned that it is better to send money to the organizations doing the relief work than to try to organize shipments of goods.


Figure 2. Morning radar image of 94L from the Key West radar.

94L
A 1010 mb low pressure system (94L) near the Florida Keys is generating disorganized heavy thunderstorms over Florida and the adjacent waters, and could become a tropical or subtropical depression as early as Wednesday. Current Key West radar shows the rotation of the storm, but the thunderstorm activity has not yet organized into low-level spiral bands. A few areas in the Keys and extreme South Florida have seen 1 - 2 inches of rain thus far from 94L. Wind shear is currently a moderate 10 - 20 knots over 94L, and water temperatures are very warm, 30 - 31°C. Water vapor satellite imagery shows that 94L is forming beneath an upper-level low with plenty of dry air, and there is a substantial flow of dry, continental air wrapping into 94L. This dry air is retarding the development of 94L, and may force the storm to organize into a subtropical storm instead of a tropical storm. A subtropical storm typically has a large, cloud free center of circulation, with very heavy thunderstorm activity in a band removed at least 100 miles from the center. The difference between a subtropical storm and a tropical storm is not that important as far as the winds they can generate, but tropical storms generate more rain. There is no such thing as a subtropical hurricane. If a subtropical storm intensifies enough to have hurricane force winds, than it must have become fully tropical. It usually takes at least two days for a subtropical storm to make the transition to a tropical storm.

Forecast for 94L
The latest SHIPS model forecast predicts that wind shear will stay in the moderate range, 10 - 20 knots, over the Gulf of Mexico this week. The storm's main problem will be dry air, and I don't expect 94L to undergo rapid development. Most of the models bring 94L ashore over Louisiana by Thursday, though the GFDL model predicts 94L could stall off the coast and not make landfall until Friday. If 94L does make landfall Thursday, it is unlikely to be a hurricane, due to all the dry air aloft in the Gulf. However, the GFDL model is predicting that the 1-day delay in landfall to Friday will allow 94L enough time to grow fully tropical and intensify into a Category 1 hurricane. I think this solution is unlikely. Storms that get their start underneath a cold, dry, upper-level low very rarely attain hurricane strength in three days. A 40 - 50 mph tropical or subtropical storm at landfall Thursday or Friday is a much more reasonable forecast.

93L
A tropical wave (Invest 93) in the middle Atlantic Ocean is close to tropical depression status. The disturbance has a well-defined surface circulation, but only a limited amount of heavy thunderstorm activity, thanks to dry air and wind shear of 10 - 20 knots affecting it due to a large upper-level low pressure system to the west. Wind shear is expected to stay in the moderate range, 10 - 20 knots, over the next four days, which is low enough that 93L could become a tropical depression at any time during that period. NHC is giving 93L a 60% chance of developing into a tropical depression by Thursday morning. The GFS, GFDL, and HWRF models predict 93L will develop, and the GFDL forecasts that the storm will become a hurricane. A strong trough of low pressure moving across the central Atlantic is recurving 93L to the north, and the system should only be a concern to shipping interests. None of the reliable computer models are forecasting tropical cyclone development in the Atlantic over the next seven days, other than for 93L and 94L.

Moscow hits 99°F again today
Temperatures at Moscow's Domodedovo airport hit 37°C (99°F) today, the 28th day in row that temperatures have exceeded 30°C (86°F) in Moscow. The average high temperature for August 10 is 21°C (69°F). Moscow's high temperature have averaged 15°C (27°F) above average for the first ten days of August--a truly extraordinary anomaly. Smog and smoke from wildfires continued to blanket the city today, with the Russian Meteorological Agency reporting that pollution due to carbon monoxide, nitrogen dioxide, ozone, and hydrocarbons exceeding the safe limit by factors of 1.2 - 2.2. Air pollution levels peaked at 6.5 times the safe level on Saturday. As I reported in yesterday's post, the heat wave has likely killed at least 15,000 people in Russia so far. There is some slight relief in sight--the latest forecast for Moscow calls for high temperatures of 31 - 33°C (88 - 91°F) Wednesday though Sunday--still 20°F above normal, but better than the 27°F above normal so far this month.

"Hurricane Haven" airing again this afternoon
Tune into another airing of my live Internet radio show, "Hurricane Haven", at 4pm EDT today. Listeners will be able to call in and ask questions. The call in number is 415-983-2634, or you can post a question in the comments area on my blog during the show. You can also email the questions to me today before the show: jmasters@wunderground.com. Be sure to include "Hurricane Haven question" in the subject line. Some topics I'll cover today on the show:

1) Invest 94 and 93
2) A look ahead at the coming two weeks
3) Status of La Niña

Today's show will be about 30 minutes, and you can tune in at http://www.wunderground.com/wxradio/wubroadcast.h tml. The show will be recorded and stored as a podcast.

Jeff Masters

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1938. wxhatt
The ULL is moving out to the west fairly quickly. Most of the dry air is gone now and overnight the upper level conditions will improve for outflow in all quadrants.



Member Since: October 5, 2005 Posts: 2 Comments: 927
1937. gator23
Quoting msgambler:
I did say senseable.

touche'
Member Since: Posts: Comments:
1936. Ossqss
If you have not, you should check your generators. There have been many issues with bad gas in them lately, in particular ethanol blended gas. Heads up folks, spoken from 1st hand neighborhood experiences. Sta-Bil helps.

Hurricane season: Ethanol gas left in generators may disable them, experts say
Member Since: June 12, 2005 Posts: 6 Comments: 8186
1935. Patrap
Cyclone OZ is en route to Louisiana.

Breaking Web News.
Member Since: July 3, 2005 Posts: 426 Comments: 129093
Quoting gator23:

i know your a gambler but DONT BET ON IT!! lol
I did say senseable.
Member Since: Posts: Comments:
TD5 needs to put on a convective burst tonight if it wants to become a hurricane.
Member Since: July 15, 2006 Posts: 17 Comments: 10284
1932. JLPR2
Quoting gator23:

3 cat 5's hit the US and Ike is the worse storm sheesh the ego of these everything is bigger in Texans lol


haha!
yep
Member Since: September 4, 2007 Posts: 7 Comments: 8747
Quoting Patrap:
Ike had a MAx storm Surge of 17 feet and took 74 Lives.

Katrina had a 30 ft Storm Surge and took over 1500 in 3 States.

So in what way was Ike more destructive than Katrina?


Thats ridiculous.

IKE
Country Deaths Missing
Haiti 74 ???
Dominican Republic 2 ???
Cuba 7 ???
United States 112 34
Total 195 34

Member Since: Posts: Comments:
1930. gator23
Quoting msgambler:
I figured you would, most senseable poeple do....LOL

i know your a gambler but DONT BET ON IT!! lol
Member Since: Posts: Comments:
1929. gator23
Quoting JLPR2:


and the list goes on. XD
Oh and how could I forget Camille, pfft, just a rain shower
XD

3 cat 5's have hit the US and Ike is the worse than all of them. sheesh the ego of these everything is bigger in Texans lol
Member Since: Posts: Comments:
1928. Drakoen
Quoting HurricaneKyle:


94L?
invest_RENUMBER_al942010_al052010.ren


I know
Member Since: October 28, 2006 Posts: 57 Comments: 30615
Quoting clwstmchasr:


I don't see that it has been declared.
invest_RENUMBER_al942010_al052010.ren
Member Since: September 2, 2009 Posts: 130 Comments: 21194
Quoting gator23:

well you didnt really get there but I see your point.
I figured you would, most senseable people do....LOL
Member Since: Posts: Comments:
Quoting fallinstorms:
IKE WAS worse then katrina

Ike and Katrina were two VERY DIFFERENT storms...both extremely destructive. You need to stop with all these crazy comments


Member Since: Posts: Comments:
there is your hot towers
Member Since: Posts: Comments:
Quoting Drakoen:
94L is exhibiting a good lower level convergence and upper level divergence and an upper level high is developing over the system.


94L?
invest_RENUMBER_al942010_al052010.ren
Member Since: August 10, 2009 Posts: 3 Comments: 672
Quoting muddertracker:
Did St. Bernard ever get their money? I watched a heartbreaking doc on St. Bernard a few weeks ago. It was about the shipping channel (lane?) that was built and how it played a role in the flooding in 2005.


The people of St Bernard made out very well. Im not sure they received additional money from the MRGO lawsuit but most made out well with The Road Home money and from their own insurance companies...
Member Since: July 23, 2010 Posts: 0 Comments: 28
1920. JLPR2
Quoting gator23:

lol and Hugo and Great Miami and Lake Okeechobee and Galveston...


and the list goes on. XD
Oh and how could I forget Camille, pfft, just a rain shower
XD
Member Since: September 4, 2007 Posts: 7 Comments: 8747
1919. Patrap
Quoting msgambler:
Concider the source




But,I digress..

Just call me Carl
Member Since: July 3, 2005 Posts: 426 Comments: 129093
And the HH found.... squat.



AOI

AOI

AOI

AOI

AOI

TS BUSTED FORECAST ALIBI
Member Since: Posts: Comments:
All 3 features currently being monitored by the NHC are accompanied by good upper divergence.

Member Since: September 2, 2009 Posts: 130 Comments: 21194
1916. Ossqss

Member Since: June 12, 2005 Posts: 6 Comments: 8186
1914. gator23
Quoting msgambler:
I guess that depends on where you are. If you were in Gulfport/Biloxi then Ike was a rain shower.

well you didnt really get there but I see your point.
Member Since: Posts: Comments:
Quoting Patrap:
Ike had a MAx storm Surge of 17 feet and took 74 Lives.

Katrina had a 30 ft Storm Surge and took over 1500 in 3 States.

So in what way was Ike more destructive than Katrina?


Thats ridiculous.
Concider the source
Member Since: Posts: Comments:
No advisory package yet from the NHC.
Member Since: Posts: Comments:
1911. xcool
Hardcoreweather2010 :(
Member Since: September 26, 2009 Posts: 2 Comments: 15684
1910. gator23
Quoting JLPR2:


pfft, add Wilma and Mitch to that

-.-

lol and Hugo and Great Miami and Lake Okeechobee and Galveston...
Member Since: Posts: Comments:
Quoting fallinstorms:
IKE WAS worse then katrina

I guess that depends on where you are. If you were in Gulfport/Biloxi then Ike was a rain shower.
Member Since: Posts: Comments:
1908. Patrap
Ike had a MAx storm Surge of 17 feet and took 74 Lives.

Katrina had a 30 ft Storm Surge and took over 1500 in 3 States.

So in what way was Ike more destructive than Katrina?


Thats ridiculous.
Member Since: July 3, 2005 Posts: 426 Comments: 129093
1907. Drakoen
94L is exhibiting a good lower level convergence and upper level divergence and an upper level high is developing over the system.
Member Since: October 28, 2006 Posts: 57 Comments: 30615
1906. angiest
The interesting things always happen while I am away. Where are people seeing 05L being declared? And does anyone have a position fix for it yet?
Member Since: Posts: Comments:
Quoting HurricaneKyle:


94L was renumbered TD5, its on the Navy site as well.

Yeah, I just saw it. Thanks!
Member Since: August 18, 2008 Posts: 0 Comments: 884
Quoting xcool:
Am I Right by Biloxi ms


you will be under a tropical storm watch very soon :)
Member Since: Posts: Comments:
1903. JLPR2
Quoting gator23:

right.... and worse then Andrew


pfft, add Wilma and Mitch to that

-.-
Member Since: September 4, 2007 Posts: 7 Comments: 8747
Recon will be heading out to investigate 05L once more at 12:30 AM EDT (arriving at 2AM EDT).

FLIGHT TWO -- TEAL 71
A. 11/0600Z -1200Z
B. AFXXX 0205A CYCLONE
C. 11/0430Z
D. 27.0N 85.5W
E. 11/0500 -1200Z
F. SFC TO 15,000 FT
Member Since: September 2, 2009 Posts: 130 Comments: 21194
Quoting weatherwart:
Evening all! Still have 94L, I see. No classification yet. Seems like there's still a lot of dry air around and look at that big ridge to the north.

Link


94L was renumbered TD5, its on the Navy site as well.
Member Since: August 10, 2009 Posts: 3 Comments: 672
Quoting gator23:

it is close enough to land that there will be regular 8 11 2 and 5 o clock updates. not special.
I was talking about the first advisory.
Member Since: Posts: Comments:
1899. gator23
Quoting Hardcoreweather2010:
A Tropical Storm watch will be issued from Morgan City, LA to Mobile, AL

where is that from?
Member Since: Posts: Comments:
1898. xcool
Am I Right by Biloxi ms
Member Since: September 26, 2009 Posts: 2 Comments: 15684
1896. angiest
Quoting gator23:

it is close enough to land that there will be regular 8 11 2 and 5 o clock updates. not special.


Unless it comes out at the normal full advisory time, then it will be a special advisory since it will contain the full package.
Member Since: Posts: Comments:
Quoting weatherwart:
Evening all! Still have 94L, I see. No classification yet. Seems like there's still a lot of dry air around and look at that big ridge to the north.

Link


We have TD #5
Member Since: July 6, 2010 Posts: 113 Comments: 32528
1894. gator23
Quoting fallinstorms:
IKE WAS worse then katrina


right.... and worse then Andrew
Member Since: Posts: Comments:
1893. gator23
Quoting weatherwart:
Evening all! Still have 94L, I see. No classification yet. Seems like there's still a lot of dry air around and look at that big ridge to the north.

Link

its TD5
Member Since: Posts: Comments:
1891. Patrap
94L is now TD-5
Member Since: July 3, 2005 Posts: 426 Comments: 129093
A Tropical Storm watch will be issued from Morgan City, LA to Mobile, AL
Member Since: Posts: Comments:
1888. gator23
Quoting KATRINABILOXIGIRL:
I wouldn't call Katrina not getting any action. I have the video of him on Front Beach in Biloxi telling everyone to take a good look at what they saw behind him because it will never look the same again. He was right. If any were wondering why they didn't see full coverage of the storm from him is because they lost their satellite vehicles and then went into rescue mode to help all of the people in danger at the Navy retirement home that they had to retreat to for safety and that still was not far enough away from the surge. So any way, we have people on Cantore watch anytime a storm heads this way so we can refuse entry into our area...LOL just kidding...

I think Biloxi got worse winds from Katrina I think Biloxi was overshadowed by the flood in NOLA unfortunately
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About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.