Pakistan monsoon floods kill at least 800

By: Dr. Jeff Masters , 5:56 PM GMT on July 31, 2010

Share this Blog
3
+

The deadliest weather disaster of 2010 is unfolding in Pakistan, where heavy monsoon rains have triggered flooding that has left at least 817 people dead. A death toll may reach 3000, according to the local head of Pakistan's largest rescue service, and more monsoon rains are on the way. Monsoon floods have also hit southeastern Afghanistan hard, where at least 64 have been killed. The heavy rains were caused by a monsoon depression (also called a monsoon low) that formed over the Bay of Bengal 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, resulting in that nation's worst floods since at least 1929. 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 monsoon depression is similar to a tropical depression, but forms in the Indian Southwest Monsoon over the Bay of Bengal. Like tropical depressions, monsoon depressions are hundreds of miles in diameter, have nearly calm winds near the center, and can have sustained winds of 30 - 35 mph. Four monsoon depressions originated in the Bay of Bengal in 2009; the average is 6 - 7. A new monsoon depression developed over the Bay of Bengal yesterday, and is headed westward towards Pakistan. Heavy rains from this new monsoon depression will begin affecting Pakistan on Monday, according to the Pakistan Meteorological Department.


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.

Tropical Atlantic may get active by mid-week
The Invest 90L tropical wave off the coast of Africa has grown disorganized, and NHC is no longer generating forecast tracks for the system. A tropical wave that moved of the coast of Africa Thursday is in the eastern Atlantic near 10N 25W, a few hundred miles south of the Cape Verdes Islands. This morning's 12Z run of the NOGAPS model predicts that this wave will develop into a tropical storm by Wednesday, and reach the Lesser Antilles Islands Friday. This morning's 12Z run of the GFS and ECMWF models predict that an area of disturbed weather near 8N 37W, in the east-central Atlantic, will develop into a tropical storm that will move through the Lesser Antilles on Thursday. Wind shear is low to moderate, sea surface temperatures are at record highs, and the dust and dry air of the Saharan Air Layer (SAL) are far enough to the north of these disturbed areas to potentially allow formation of a tropical storm. However, the Madden-Julian Oscillation currently favors downward motion over the tropical Atlantic, which will act to decrease the chances of tropical storm formation. NHC is giving a 30% chance that a tropical depression will form by Monday afternoon from one of these areas of disturbed weather.

Next update
I'll have an update Monday morning at the latest.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 120 - 70

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 | 61Blog Index

Anyone know if the NCEP tropical desk updates their Caribbean Outlook over the weekend? They usually do a very good analysis with the models and TUTT issues but have not updated since yesterday afternoon.
Member Since: Posts: Comments:
cirrocumulus, they don't have to assign invests on the twos. maybe we'll see one here shortly.

That's weird. Just noticed it says Sept. 2005.
It's on this page africanweather
Member Since: Posts: Comments:
In all reality, even though it is nice to have the info from declaring invests, it seems kind of pointless to declare one right now until they know where to estimate a center.
Member Since: Posts: Comments:
Quoting AllStar17:


Certainly.

However, where is even one invest?


At the moment there are none which is funny lol. They can do whatever they want with them though because there are no criteria for labeling invests or deactivating them.
Member Since: Posts: Comments:
116. IKE
12Z UKMET @ 72 hours....



Member Since: Posts: Comments:
AOI/XX/XL
MARK
7.7N/35.1W
Member Since: Posts: Comments:
NHC could punt for a few model cycles and wait for the scenerio described in the TWD to occur.

IT IS ANTICIPATED THAT AS THE TROPICAL WAVE NEAR THE CAPE VERDE ISLANDS APPROACHES FROM THE EAST...THAT FURTHER DEVELOPMENT AND ORGANIZATION OF CONVECTION IS POSSIBLE IN THE VICINITY OF THE SURFACE TROUGH ALONG 34W.
Member Since: Posts: Comments:
Quoting Levi32:


16 hours 49 minutes and losing 5 minutes a day now.
i know i have been following the sun back across the sky the pace quickens now
Member Since: Posts: Comments:
Levi32: Have you had any cabbage soup this summer? Any pictures of those large vegetables. Hope I don't get flagged for OT since we're only at orange30 status.
Member Since: Posts: Comments:
I see NHC has an orange circle but no invest. What is up with that?
Member Since: Posts: Comments:
Quoting Levi32:


Would be very dumb to label two invests when they are going to combine.


Certainly.

However, where is even one invest?
Member Since: Posts: Comments:
Chicklit: Masters is just needing a vacation from his vacation. I will say that Levi agrees with my synopsis of "orange30". The 35 spin is still active, but Masters seemed to debunk. I just think they are unsure with the "big blob".
Member Since: Posts: Comments:
Quoting MiamiHurricanes09:
Hey Levi! Great video update as always!


Thanks :)
Member Since: Posts: Comments:
Quoting CybrTeddy:


I meant to say Monday, my brain still keeps on telling me its still Friday.
Sunday sounds good, I'm just moving towards a safer standpoint. Lol.
Member Since: Posts: Comments:
Quoting KEEPEROFTHEGATE:
what a beautiful day it is outside how many hrs of daylight ya get now levi


16 hours 49 minutes and losing 5 minutes a day now.
Member Since: Posts: Comments:
Quoting CybrTeddy:
Chick, they always designate invest when they hit 30%. Never seen a orange without a invest tag for long.

oh. maybe they're just buying time since it obviously isn't going to affect land in the next 12 hrs. l8r
Member Since: Posts: Comments:
Quoting extreme236:


I know it is very unlikely, but what are the odds of two separate entities forming?


Like you said, very unlikely lol. The only way it would happen is the CMC's depiction....which is almost always wrong when you see something like that. Logically, ex-90L is still stalling while the wave behind is still catching up and has more than enough time to overtake the system and start merging into it.
Member Since: Posts: Comments:
Quoting IKE:
12Z ECMWF @ 144 hours....





BUT IT WILL DEVELOP NO MATTER WHAT! :D

Yes, I am a wishcaster. :P
Member Since: Posts: Comments:
Quoting Levi32:


I think it will remain the dominant circulation, yes.
Hey Levi! Great video update as always!
Member Since: Posts: Comments:
Quoting MiamiHurricanes09:
Still remains rather disorganized at the surface exhibiting a broad area of low pressure, but as convection continues to organize and its low continues to consolidate we may be dealing with "code red" by Monday the latest, IMO.


I meant to say Monday, my brain still keeps on telling me its still Friday.
Member Since: July 8, 2005 Posts: 259 Comments: 23878
Quoting cirrocumulus:
Bordanaro: good call on too much caffeine in heat! Water is better. Liquids are better than nothing though.

A quart of Pepsi in, you will sweat and urinate about 38OZ out.

Live in DFW, TX, we have much lower RH and Heat indicies, we have temps that average 96-103F for 60-90 days every year.

Had Heat Stress, very, very bad. Humans are NOT superman!
Member Since: Posts: Comments:
99. IKE
12Z ECMWF @ 144 hours....



Member Since: Posts: Comments:
Chick, they always designate invest when they hit 30%. Never seen a orange without a invest tag for long.
Member Since: July 8, 2005 Posts: 259 Comments: 23878
Quoting CybrTeddy:
This 'could' be red by Sunday pm, this will be a slow process to form. Very slow.
Still remains rather disorganized at the surface exhibiting a broad area of low pressure, but as convection continues to organize and its low continues to consolidate we may be dealing with "code red" by Monday the latest, IMO.
Member Since: Posts: Comments:
Quoting ElConando:


So you think the central Atlantic wave with absord the Cape verde wave?


I think it will remain the dominant circulation, yes.
Member Since: Posts: Comments:
Quoting AllStar17:


That's what I was going to say. How about 2 invests?


Would be very dumb to label two invests when they are going to combine.
Member Since: Posts: Comments:
Hi all, thanks for the update Dr. Masters.
Two in one Saturday is a sign of active tropics.
Don't think they'll designate an invest until the entire area begins to organize. Looks pretty broad right now.


And holy blobova!
Check out the bomb still on the continent.
bbl
Member Since: Posts: Comments:
Quoting deautschlandfutbol:
So it looks as if the a/b ridge is setting up for a florida hit over and over this year. Hey hollywood r u in fla?

It has been most of the year but some of the models are showing the center of the A/B high retreating a little to the east with a couple lows dipping in the north out of Canada. Could be good timing for some if something nasty were to develop.
Member Since: Posts: Comments:
This 'could' be red by Monday pm, this will be a slow process to form. Very slow.
Member Since: July 8, 2005 Posts: 259 Comments: 23878
Quoting weathermanwannabe:


Can't help myself.....I'm a Pepsi freak..... :)

I would recommend becoming an ice-water, Gatorade & Pepsi freak. HEAT is a killer man.
Member Since: Posts: Comments:
Bordanaro: good call on too much caffeine in heat! Water is better. Liquids are better than nothing though.
Member Since: Posts: Comments:
Quoting HaboobsRsweet:

The convection is fairly disorganized and even on the loops you can tell it is just a lot of blow off and very little convecton overall. Mostly mid clouds and blow off cirrus. I think in the next 24 hours it will be a n invest and maybe in 72 hours we creep out of the orange range.
Telling from AVN images it has more than just a little bit of convection. Also telling from the conditions it is in 3 days sounds like a little too much time...by then we may be dealing with 04L, IMO.

Member Since: Posts: Comments:
Quoting Bordonaro:

Stay hydrated with non-alcoholic and non-caffeinated beverages, or you'll regret being outside all afternoon!


Can't help myself.....I'm a Pepsi freak..... :)
Member Since: Posts: Comments:
Quoting Levi32:


Ouch lol. 52 degrees and raining here.

88 degrees and sunny here. I wish it was 52 degrees and raining.
Member Since: July 7, 2010 Posts: 0 Comments: 5672
Levi32: It does look like 35W. That's where the spin/convection showed promise on the floater on visible/infrared. I'd say you have the correct ratio.
Member Since: Posts: Comments:
Well this is gonna be a very high risk flroida year because of the a/b high and the neg nao. Gonna be bad for the bahamas this year too. Yeah I'm in florida to hollywood. Its just that kinda feel for this year.
Member Since: Posts: Comments:
Quoting weathermanwannabe:
99 degrees in Tallahassee right now and I just refreshed my drink..........Not going outside again until the sun goes down.......

Stay hydrated with non-alcoholic and non-caffeinated beverages, or you'll regret being outside all afternoon!
Member Since: Posts: Comments:
Quoting HurricaneSwirl:


I'm expecting him to say very unlikely lol. Pretty much answered your own question ;)


Yeah lol...I was just curious if he thought there was any slight chance of it happening.
Member Since: Posts: Comments:
Quoting HaboobsRsweet:

The convection is fairly disorganized and even on the loops you can tell it is just a lot of blow off and very little convecton overall. Mostly mid clouds and blow off cirrus. I think in the next 24 hours it will be a n invest and maybe in 72 hours we creep out of the orange range.


Well the IR images show there is more than just a little convection. Code orange is typically when an invest is declared if it hasn't already been. I don't see it taking 3 days to get to red but that's jmo
Member Since: Posts: Comments:
Quoting CybrTeddy:
MJO doesn't kill off disturbances once they are there. They help make sure disturbances don't form.
Well said Ted.
Member Since: Posts: Comments:
Quoting extreme236:


I know it is very unlikely, but what are the odds of two separate entities forming?


I'm expecting him to say very unlikely lol. Pretty much answered your own question ;)
Member Since: Posts: Comments:
99 degrees in Tallahassee right now and I just refreshed my drink..........Not going outside again until the sun goes down.......
Member Since: Posts: Comments:
Quoting Levi32:


Likely at what really is still 90L's circulation, elongated as it is, near 8.5N, 35W.

They could also put one just SW of the CV islands, but that area of rotation is less impressive, and the former seems likely to absorb the latter more than the other way around, but we shall see.


So you think the central Atlantic wave with absord the Cape verde wave?
Member Since: Posts: Comments:
The bottom of that orange circle is near Antarctica so the bases are covered.
Member Since: Posts: Comments:
Quoting AllStar17:
I still am confused as to why our disturbance is not 91L.

Judging by this visible loop, it continues to become better organized.

The convection is fairly disorganized and even on the loops you can tell it is just a lot of blow off and very little convecton overall. Mostly mid clouds and blow off cirrus. I think in the next 24 hours it will be a n invest and maybe in 72 hours we creep out of the orange range.
Member Since: Posts: Comments:
Quoting Levi32:


Likely at what really is still 90L's circulation, elongated as it is, near 8.5N, 35W.

They could also put one just SW of the CV islands, but that area of rotation is less impressive, and the former seems likely to absorb the latter more than the other way around, but we shall see.


That's what I was going to say. How about 2 invests?
Member Since: Posts: Comments:
Quoting Levi32:


Likely at what really is still 90L's circulation, elongated as it is, near 8.5N, 35W.

They could also put one just SW of the CV islands, but that area of rotation is less impressive, and the former seems likely to absorb the latter more than the other way around, but we shall see.


I know it is very unlikely, but what are the odds of two separate entities forming?
Member Since: Posts: Comments:
CPHC just updated with the 8AM (2PM EDT) outlook..

Issued: Jul 31, 2010 8:03 am HST

For the central north Pacific, between 140°W and 180.

1. A weak surface trough centered about 1150 miles southeast of Hilo, Hawaii has disorganized showers and isolated thunderstorms associated with it. Although upper level winds are currently not conducive for any significant development of this system, these winds may relax slightly later this weekend as this trough continues moving westward at 10 to 15 mph. There is low chance, 20 percent, of this system becoming a tropical cyclone during the next 48 hours.

Elsewhere, no tropical cyclones are expected through Monday morning.

They still kept it at 20%.
Member Since: Posts: Comments:
Quoting Levi32:


Ouch lol. 52 degrees and raining here.
what a beautiful day it is outside how many hrs of daylight ya get now levi
Member Since: Posts: Comments:
Quoting nrtiwlnvragn:
Interested to see where in that 500 mile orange circle they initiate an invest.


Likely at what really is still 90L's circulation, elongated as it is, near 8.5N, 35W.

They could also put one just SW of the CV islands, but that area of rotation is less impressive, and the former seems likely to absorb the latter more than the other way around, but we shall see.
Member Since: Posts: Comments:
Quoting cirrocumulus:
I'm going 60% right now on 91L. No money at stake on the bet. I am hedging on warm water temps overriding the MJO.


That's probalby a good bet right now assuming that a solid low can develop over the next few days........
Member Since: Posts: Comments:

Viewing: 120 - 70

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 | 61Blog Index

Top of Page

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.