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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Quoting JLPR2:


Yeah and he misinterpreted the comment too, 2005 did only have 2 named storms by this time in August, not talking about June and July.


right I was referring to August
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dos any one have a link too the ACTF site or what evere its called
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From here in Tampabay, you can tell 94L is coming to life out there...

Been getting a little gustier all day and getting small bands going through periodically with breif heavy rain. I can see the low clouds moving much faster today than yesterday, definately winding up.
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Quoting WxLogic:


Thx nrt... interesting read indeed.


Liked this part, I forecast a few in here going through it.


We’ve had an infusion of new blood in the hurricane specialist unit during the past few years. Do you see in them a little bit of what you went through?
Oh yes. Some of them are really excited just like me. They think they know how to forecast and come in very “pompous”. But everyone will learn, or have already learned, that it’s not that simple. When I finished fresh from school, I thought I was going to solve all of the problems, be able to predict intensity, be able to do everything. But as soon as you put your name on that forecast, you become very humble. And that’s good. I am glad people are coming with a lot of enthusiasm, and they bring new ideas and new techniques.
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Quoting VAbeachhurricanes:


I am chill... all I ever said was that the start of August has been slow. Then you just say that 2 storms, in 2005 before a K storm? that makes alot of sense...


it does, 2005 was slow for most of August and with all indications showing we could have a very active next 2 weeks in the tropics we could easily come much closer to 2005s #s by then.
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Quoting hurricanehanna:
Storm, Levi, someone...please make sense of what the center is doing puh-lease..... :)


18Z (1hr 46min ago)

AL, 94, 2010081018, , BEST, 0, 258N, 837W, 25, 1009, LO,

Moving 5-10 off to the WNW. More on the 5 side, it's moving slooooow.
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1079. IKE
Quoting HurricaneKyle:


Still a pretty good score board to me. We're about average. 2009 at this time was 0/0/0.


I agree...we are average.

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Quoting HurricaneKyle:
Ike's not a downcaster, he doesn't make trollish remarks like..

'ROFL what a bust season next!!!', true he does sling a little bit to the conservative side but who would want storms to form and hit land?
Anywhere in that paragraph did I call IKE a downcaster? I did state however that he possesses a bias for tropical inactivity... and who said anything about wanting storms hitting land?
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Quoting HurricaneKyle:


Still a pretty good score board to me. We're about average. 2009 at this time was 0/0/0.


not only are we average, we are average for a hyperactive season

as was stated by SLU yesterday the average storm #s from seasons since 1995 is 3 on August 9th, which is where we are

as Levi stated today, the average # of named storms by the 15th of August for all hyperactive seasons is 4; we are close to getting #4 right now
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1075. divdog
Quoting IKE:


Think what you want. I can't help what the models show. I usually post...the ECMWF...GFS...CMC and NOGAPS.

Psst...if it doesn't show much....don't blame me.

Look at the scoreboard.....

3-1-0...so far...in 2010.
You call them as you see them
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The area E of Barbados is getting better organized and should become Invest 95L later tonight or early tomorrow.
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Quoting Hurricanes101:


wow you need to chill out man lol

2010 is not slow, your initial post was with a tone that showed it was slow


I am chill... all I ever said was that the start of August has been slow. Then you just say that 2 storms, in 2005 before a K storm? that makes alot of sense...
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Central Florida area here and we have had rain off and on all day. Family in the Tampa area. Wonder how they are getting along.
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1071. JLPR2
Quoting Hurricanes101:


wow you need to chill out man lol

2010 is not slow, your initial post was with a tone that showed it was slow


Yeah and he misinterpreted the comment too, 2005 did only have 2 named storms by this time in August, not talking about June and July.
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1070. pottery
1.25" here in 1 hour from a typical afternoon boomer-storm.
Sounded like a sound-bite from "The Guns of Navarone".
All clear now.

Out to do some planting now, under Instructions from a Higher Authority.
Some people have NO IDEA how important this weather-watching stuff is !!
Member Since: October 24, 2005 Posts: 0 Comments: 25653
1069. A4Guy
Is it.....?
Could it be....?
Are my eyes deceiving me....?

But is 94L forming a PINHOLE EYE????

(OK...just had to do that, becasue someone will probably ask and actually be serious).
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Quoting IKE:


Think what you want. I can't help what the models show. I usually post...the ECMWF...GFS...CMC and NOGAPS.

Psst...if it doesn't show much....don't blame me.

Look at the scoreboard.....

3-1-0...so far...in 2010.


Still a pretty good score board to me. We're about average. 2009 at this time was 0/0/0.
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1067. angiest
18z early models showing the same thing, roughly:

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Quoting MaximumDestruction:
MAX D's Official Prediction for 94L:

Peak Intensity: 145 MPH 908 mb

Intensity at landfall: 130 MPH 940 mb

Landfall location: Intracoastal City, LA


Take it to the bank

um no i want to keep my money go watse urs though
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1065. snotly
Quoting Jeff9641:
Anybody see this east of Barbados. Very interesting!

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


uh oh.
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Ike is not a downcaster but a real caster...why jump on people who so call downcast? Between last year and this year the so called downcasters have been right more than the people forecast TSs and hurricanes. Maybe you should listen to him more often.
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1062. IKE
Quoting JLPR2:
93L's circulation has weakened, not as defined as earlier today

SSD 93L FLOATER


I agree with you on 93L.
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Quoting VAbeachhurricanes:


so you admit you are BSing through this entire argument? haha, having 10 named through August is not slow by any definition! are you crazy? or just stupid?


wow you need to chill out man lol

2010 is not slow, your initial post was with a tone that showed it was slow
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1058. IKE
Quoting TankHead93:
IKE, you too contribute to the bi-polarness of this blog... how you ask? even though you don't switch your perspective on a tropical disturbance/cyclone based on the appearance like many others do, you have an extreme bias for inactivity in the Atlantic basin, posting numerous times only model runs showing absolutely no tropical cyclone development from only the European model. When you put your bias for inactivity of tropical activity with other user's extreme wishcasting/upcasting it creates for an extreme bipolar atmosphere on this blog.


Think what you want. I can't help what the models show. I usually post...the ECMWF...GFS...CMC and NOGAPS.

Psst...if it doesn't show much....don't blame me.

Look at the scoreboard.....

3-1-0...so far...in 2010.
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1056. FLDART1
Unless you are some sort of Deity, Then NO ONE in here can forecast the weather with 100% accuracy...lol
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1055. ssmate
Quoting ElConando:
987. Tonight will be telling.
I don't think we will want to hear what it's saying.
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1053. angiest
Interesting hard turn to the right in some of the models.

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Ike's not a downcaster, he doesn't make trollish remarks like..

'ROFL what a bust season next!!!', true he does sling a little bit to the conservative side but who would want storms to form and hit land?
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Quoting TankHead93:
IKE, you too contribute to the bi-polarness of this blog... how you ask? even though you don't switch your perspective on a tropical disturbance/cyclone based on the appearance like many others do, you have an extreme bias for inactivity in the Atlantic basin, posting numerous times only model runs showing absolutely no tropical cyclone development from only the European model. When you put your bias for inactivity of tropical activity with other user's extreme wishcasting/upcasting it creates for an extreme bipolar atmosphere on this blog.


Totally agree
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1049. JLPR2
93L's circulation has weakened, not as defined as earlier today

SSD 93L FLOATER
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1048. NASA101
Quoting Hurricanes101:



shhhhh don't cloud them with logic lol


HAHAHAHHA
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1044. WxLogic
Quoting nrtiwlnvragn:
q_and_a_201009_lixion_avila

Interesting read.


Thx nrt... interesting read indeed.
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Quoting StormW:
img src="Photobucket" alt="" />


I think the center is just a bit further west StormW, but yea you got the idea lol
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1042. JLPR2
Quoting VAbeachhurricanes:
I NEVER said anything about a slow season!!! omg, I said the START of august was slow! jimminy crickets...


haha! XD
yeah, August has been slow so far
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From Sat loops 93L is a TD although not called yet. It's got the convection now sitting just east but over the already existing circulation. We need a SCAT Floater!!!

The AOI at 50W and 12N is organizing fast since yesterday.
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1040. pottery
Quoting KennyNebraska:


You're not a wishcaster, I know. Just desperate. Take care out there. And remember, this system is going to cause many other people problems in the days ahead. I can feel it.

I hope you are wrong. But....
In any case, no mention of it in the Official discussions as yet.
Member Since: October 24, 2005 Posts: 0 Comments: 25653
I NEVER said anything about a slow season!!! omg, I said the START of august was slow! jimminy crickets...
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Dr. Masters co-founded wunderground in 1995. He flew with the NOAA Hurricane Hunters from 1986-1990. Co-blogging with him: Bob Henson, @bhensonweather

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