Causes of the Russian heat wave and Pakistani floods

By: Dr. Jeff Masters , 2:56 PM GMT on August 13, 2010

Share this Blog
4
+

The Great Russian Heat Wave of 2010 is one of the most intense, widespread, and long-lasting heat waves in world history. Only the European heat wave of 2003, which killed 35,000 - 50,000 people, and the incredible North American heat wave of July 1936, which set all-time extreme highest temperature records in fifteen U.S. states, can compare. All of these heat waves were caused by a highly unusual kink in the jet stream that remained locked in place for over a month. The jet stream is an upper-level river of air, between the altitudes of about 30,000 - 40,000 feet (10,000 - 12,000 meters). In July over Europe and Asia, the jet stream has two branches: a strong southern "subtropical" jet that blows across southern Europe, and a weaker "polar" jet that blows across northern Europe. The polar jet stream carries along the extratropical cyclones (lows) that bring the mid-latitudes most of their precipitation. The polar jet stream also acts as the boundary between cold, Arctic air, and warm tropical air. If the polar jet stream shifts to the north of its usual location, areas just to its south will be much hotter and drier than normal. In July 2010, a remarkably strong polar jet stream developed over northern Europe. This jet curved far to the north of Moscow, then plunged southwards towards Pakistan. This allowed hot air to surge northwards over most of European Russia, and prevented rain-bearing low pressure systems from traveling over the region. These rain-bearing low pressure systems passed far to the north of European Russia, then dove unusually far to the south, into northern Pakistan. The heavy rains from these lows combined with Pakistan's usual summer monsoon rains to trigger Pakistan's most devastating floods in history.


Figure 1. Winds of the jet stream at an altitude of 300 millibars (roughly 30,000 feet high). Left: Average July winds from the period 1968 - 1996 show that a two-branch jet stream typically occurs over Europe and Asia--a northern "polar" jet stream, and a more southerly "subtropical" jet stream. Right: the jet stream pattern in July 2010 was highly unusual, with a very strong polar jet looping far to the north of Russia, then diving southwards towards Pakistan. Image credit: NOAA/ESRL.

What caused this unusual jet stream pattern?
The unusual jet stream pattern that led to the 2010 Russian heat wave and Pakistani floods began during the last week of June, and remained locked in place all of July and for the first half of August. Long-lived "blocking" episodes like this are usually caused by unusual sea surface temperature patterns, according to recent research done using climate models. For example, Feudale and Shukla (2010) found that during the summer of 2003, exceptionally high sea surface temperatures of 4°C (7°F) above average over the Mediterranean Sea, combined with unusually warm SSTs in the northern portion of the North Atlantic Ocean near the Arctic, combined to shift the jet stream to the north over Western Europe and create the heat wave of 2003. I expect that the current SST pattern over the ocean regions surrounding Europe played a key role in shifting the jet stream to create the heat wave of 2010. Note that the SST anomaly pattern is quite different this year compared to 2003, which may be why this year's heat wave hit Eastern Europe, and the 2003 heat wave hit Western Europe. Human-caused climate change also may have played a role; using climate models, Stott et al. (2004) found it very likely (>90% chance) that human-caused climate change has at least doubled the risk of severe heat waves like the great 2003 European heat wave.


Figure 2. A comparison of the departure of sea surface temperature (SST) from average just prior the the start of the great European heat waves of 2003 and 2010. Temperatures in the Mediterranean Sea were up to 4°C above average in 2003, which has been implicated as a major cause of the Western European heat wave of 2003. Image credit: NOAA/NESDIS.

References
Feudale, L., and J. Shukla (2010), "Influence of sea surface temperature on the European heat wave of 2003 summer. Part I: an observational study", Climate Dynamics DOI: 10.1007/s00382-010-0788-0

Stott, P.A., Stone, D.A., and M.R. Allen (2004), "Human contribution to the European heatwave of 2003", Nature 432, 610-614 (2 December 2004) | doi:10.1038/nature03089. (Here is a free version of the paper, presented at a conference.)

The World Meteorological Organization (WMO) has posted an analysis of the recent extreme weather events, concluding, "the sequence of current events matches IPCC projections of more frequent and more intense extreme weather events due to global warming."

See also my posts, The Great Russian Heat Wave of 2010: 102°F in Moscow and, Over 15,000 likely dead in Russian heat wave; Asian monsoon floods kill hundreds more.

Moscow sees real relief from the Great Russian Heat Wave of 2010
For the first time in more than a month, temperatures at Moscow's Domodedovo airport failed to exceed 30°C (86°F) today. Clouds and thunderstorms blew into the city this morning, keeping the high temperature down to just 29°C (84°F). This breaks a string of 35 straight days when the temperature reached 30°C. At Moscow's official observing site, the Moscow Observatory, this string was 30 days. Moscow's average high temperature for August 13 is 20°C (68°F), so today's temperatures were still well above normal. However, today's cool-down marks the beginning of the end for Russia's great heat wave. The latest forecast for Moscow calls for high temperatures below 30°C for the coming week, and Moscow may not exceed that threshold for the remainder of summer. Long range forecasts from the ECMWF and GFS models continue to suggest that a series of troughs of low pressure will attack the ridge of high pressure anchored over Russia, bringing cooler temperatures just 5°C (8°F) above average to Russia late next week. By ten days from now, the ECMWF model shows a strong trough of low pressure over Moscow, and a end to the Great Russian Heat Wave of 2010. Moscow still has to concern itself with smoke from the wildfires burning southeast of the city; winds are expected to shift early next week and bring the smoke towards the city again. However, the cooler weather should aid fire-fighting efforts, so the smoke problems should not be as bad as last week's nightmare.


Figure 2. Image from NASA's Aqua satellite of smoke from wildfires burning to the southeast of Moscow yesterday, August 12, 2010. Northerly winds were keeping the smoke from blowing over the city. Image credit: NASA.

The tropics are quiet
The remnants of Tropical Depression Five continue to bring heavy rain to portions of Southeast Louisiana today. Up to five inches of rain has fallen in regions near New Orleans. The GFS model predicts that the remains of TD 5 could move off the coast of Mississippi by the middle of next week and regenerate, but none of the other models is making this forecast. Both the GFS and ECMWF models are predicting that a tropical storm will develop off the coast of Africa by next Friday, August 20.

Donations urgently needed in Pakistan
The devastation wrought by the worst flooding in Pakistan's history 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.

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: 2675 - 2625

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 | 61 | 62 | 63 | 64 | 65 | 66Blog Index

Quoting MississippiWx:


This was also written before the EURO's 12z run which brings the system to weak Tropical Storm strength. We'll see what the 00z run shows. The NAM and GFS have shown that they believe in a stronger system.

I was not sure of that I apologize. I am new and found the information thought it would be helpful. I will keep close eye on the model run next time. Thanks for the heads up
Member Since: Posts: Comments:
Strong Hurricane

Looks like it's going to the fishes on this run.

Member Since: June 9, 2007 Posts: 4 Comments: 15718
2673. xcool
model support Tropical storm XXXTD5
Member Since: September 26, 2009 Posts: 2 Comments: 15603
Found this as well.

Off Of US Southeast Coast Next Week:
I wanted to point out that a few of the models, the NAM, the Canadian and the NOGAPS model are hinting pretty strongly at some sort of development off of the US Southeast coast in the next seven days. The model details of when this development will occur differ between these three models with the NAM and NOGAPS forecasting development as soon as Monday while the Canadian model holds off until next weekend. The other model guidance like the GFS and European models do not forecast development.

Looking at the current weather picture off of the US Southeast coast, one can see a frontal system extending as far south as 27 North Latitude with an area of popcorn showers and thunderstorms just offshore of the coast of eastern and northeastern Florida, Georgia and South Carolina. Wind shear in this area is running at around 20 knots and there is a lack of mid-level vorticity. So, my judgement is that development as quick as the NAM and NOGAPS models are forecasting seem a little unrealistic and development in this area, if any, will be very slow to occur. With that said, given the proximity to the coast, I will be monitoring this area closely over the next few days.

Eastern Atlantic Development Next Week With Up To Two Named Storms Possible:
Now, let’s talk about potential development in the eastern Atlantic. All, and I mean all of the models are forecasting tropical cyclone development in the far eastern Atlantic as soon as Wednesday or Thursday. This tropical development comes from a strong tropical disturbance that is located over western Africa and should emerge off of the coast of Africa into the eastern Atlantic on Sunday. It should be noted that the GFS model has forecasted this development for at least eleven consecutive runs. It should also be noted that all of the model guidance are now forecasting two tropical cyclones in the eastern Atlantic between the coast of Africa and the Lesser Antilles in about 10 days from now and the long range GFS model is forecasting a third system forming in the eastern Atlantic in about 15 days from now. So, if the model guidance is correct (and I do think they are correct), then the parade or train of storms is about to start!!

There are a couple of other model trends that have to be mentioned. The first trend is that the model guidance as a whole is trending towards a stronger ridge of high pressure which would lead to these two systems pushing quite far west. In fact, the 06 UTC long range GFS model is forecasting a very close brush with the northern Leeward Islands around August 25th and then a visit to the east coast of Florida north of Cape Canaveral around August 29th. This is voodoo land in terms of model forecasts and should be taken with a ton and a half of salt; but the trend is going towards stronger ridging and a further west track. The European model ensemble guidance’s 10 day forecast is showing a strong ridge of high pressure across much of the Atlantic and I suspect that we may see the model guidance trend even further south and west in the coming days. In my opinion, I think we are looking at a pattern that would steer storms pretty far west in the Atlantic Basin.

I want to emphasize and implore one thing on all of you and that is if you haven’t done so already, please go over your hurricane preparedness kit and if you need supplies and can afford it, go to your local supermarket, your local Target, Wal-Mart or Lowe’s and purchase what you need. If you are new to living on the coast and don’t know how to put together a hurricane preparedness kit, then either ask a neighbor or friend or go to http://www.onestorm.org. This is a really good reference website and I highly recommend it!!

The next tropical weather discussion will be issued sometime on Sunday.
Member Since: Posts: Comments:
Quoting nolacane2009:
Found this on Crownweather.com

Ex-Tropical Depression #5:
What is left of TD 5 continues to meander around the southeastern United States and is located this morning just northwest of Montgomery, Alabama. All of the reliable forecast model guidance is forecasting that Ex-Tropical Depression 5 will start tracking to the south and southeast tonight and reach the northern Gulf of Mexico near the coast of Alabama and Mississippi on Monday. After that, the model guidance vary some on how much this system will re-intensify over the northern Gulf of Mexico. Model guidance like the GFS, Canadian and UKMET forecast that this will develop into a tropical storm while it tracks slowly westward reaching southeastern Louisiana Monday night and Tuesday. The European model, on the other hand, is weaker and forecasts that this system will be just at tropical depression strength as it tracks westward on Monday and Tuesday and coming back inland into southern Louisiana around Wednesday. It is interesting to note that the 06 UTC GFS model is forecasting a slightly more southward track which would give Ex-TD 5 more time to intensify before it forecasts it to come ashore on the upper Texas coast around Wednesday.

At this point, heavy rain with the threat for flooding will continue for at least the next 3 to 4 days across the northern Gulf coast. Additional rainfall totals across coastal southeast Louisiana, coastal Mississippi, coastal Alabama and the Florida Panhandle are expected to exceed 5 inches. This is on top of the heavy rainfall that has already accumulated across this area. So, flooding is a significant concern and those of you in this area should monitor local flood watches and warnings and take appropriate action if necessary.

Now, my opinion is that there is medium-high chance that this will regain at least tropical depression status during Monday as it tracks just offshore of the coast of Alabama and Mississippi. Environmental conditions are pretty favorable in this area and it may not take very long for it to intensify to tropical storm strength. Now, if this system tracks westward into southeast and southern Louisiana on Tuesday, then I think we’d be looking at a low to moderate tropical storm. Now, if this system take a slightly further south track like the 06 UTC GFS model is suggesting, then we may be looking at something stronger as it would have an additional 24 to 36 hours over favorable environmental conditions. All interests along the upper Texas coast, the Louisiana coast, the Mississippi coast and the Alabama coast should keep close tabs on this system. Needless to say, I will be monitoring Ex-Tropical Depression 5 very closely and will keep you all updated.


This was also written before the EURO's 12z run which brings the system to weak Tropical Storm strength. We'll see what the 00z run shows. The NAM and GFS have shown that they believe in a stronger system.
Member Since: Posts: Comments:
2670. Drakoen
Quoting hurricane23:
Twinkster,

Based on the synoptic upper air pattern being layed out by the models i'd say this disturbance makes to atleast 50-55w before any trough influence takes place. Just have to wait & see if the trough that is progged to move through the northeast US and then offshore, is stronger or weaker than progged and then also if it is slower or faster. The U.S. is hit by a mere one in six that become TD's east of 50W and S of 20N. Moreover, this looks to form well east of 50W. (Of course, some of those either dissipate in mid-ocean or go too far south, but most recurve.) So, it isn't as if the U.S. needs much luck in getting a properly timed trough to keep it protected. Rather, that is usually what happens. The anomaly is when it isn't protected. However, with it being a solid La Nina and with the prime formation period for U.S. CV storm hits during La Ninas being next week (8/15-21), one should be more vigilant than normal.



Completely agree
Member Since: Posts: Comments:
Quoting Kristina40:
Thanks nolacane! I've been trying to find info on this all evening. Most helpful.


I am going to post something else I found from there about the Atlantic and the East Coast.
Member Since: Posts: Comments:
132 hours.



Member Since: Posts: Comments:
2666. Drakoen
Big system. ROCI around 10 degrees:

Member Since: Posts: Comments:
Member Since: Posts: Comments:
Thanks nolacane! I've been trying to find info on this all evening. Most helpful.
Member Since: Posts: Comments:
Quoting hurricane23:
Twinkster,

Based on the synoptic upper air pattern being layed out by the models i'd say this disturbance makes to atleast 50-55w before any trough influence takes place. Just have to wait & see if the trough that is progged to move through the northeast US and then offshore, is stronger or weaker than progged and then also if it is slower or faster. The U.S. is hit by a mere one in six that become TD's east of 50W and S of 20N. Moreover, this looks to form well east of 50W. (Of course, some of those either dissipate in mid-ocean or go too far south, but most recurve.) So, it isn't as if the U.S. needs much luck in getting a properly timed trough to keep it protected. Rather, that is usually what happens. The anomaly is when it isn't protected. However, with it being a solid La Nina and with the prime formation period for U.S. CV storm hits during La Ninas being next week (8/15-21), one should be more vigilant than normal.



thanks
Member Since: Posts: Comments:
2662. JRRP
Member Since: Posts: Comments:
Twinkster,

Based on the synoptic upper air pattern being layed out by the models i'd say this disturbance makes to atleast 50-55w before any trough influence takes place. Just have to wait & see if the trough that is progged to move through the northeast US and then offshore, is stronger or weaker than progged and then also if it is slower or faster. The U.S. is hit by a mere one in six that become TD's east of 50W and S of 20N. Moreover, this looks to form well east of 50W. (Of course, some of those either dissipate in mid-ocean or go too far south, but most recurve.) So, it isn't as if the U.S. needs much luck in getting a properly timed trough to keep it protected. Rather, that is usually what happens. The anomaly is when it isn't protected. However, with it being a solid La Nina and with the prime formation period for U.S. CV storm hits during La Ninas being next week (8/15-21), one should be more vigilant than normal.

Member Since: Posts: Comments:
Quoting Drakoen:




Yeah, that just backs up my statement. Could be some really bad flooding issues for my area.
Member Since: Posts: Comments:
Found this on Crownweather.com

Ex-Tropical Depression #5:
What is left of TD 5 continues to meander around the southeastern United States and is located this morning just northwest of Montgomery, Alabama. All of the reliable forecast model guidance is forecasting that Ex-Tropical Depression 5 will start tracking to the south and southeast tonight and reach the northern Gulf of Mexico near the coast of Alabama and Mississippi on Monday. After that, the model guidance vary some on how much this system will re-intensify over the northern Gulf of Mexico. Model guidance like the GFS, Canadian and UKMET forecast that this will develop into a tropical storm while it tracks slowly westward reaching southeastern Louisiana Monday night and Tuesday. The European model, on the other hand, is weaker and forecasts that this system will be just at tropical depression strength as it tracks westward on Monday and Tuesday and coming back inland into southern Louisiana around Wednesday. It is interesting to note that the 06 UTC GFS model is forecasting a slightly more southward track which would give Ex-TD 5 more time to intensify before it forecasts it to come ashore on the upper Texas coast around Wednesday.

At this point, heavy rain with the threat for flooding will continue for at least the next 3 to 4 days across the northern Gulf coast. Additional rainfall totals across coastal southeast Louisiana, coastal Mississippi, coastal Alabama and the Florida Panhandle are expected to exceed 5 inches. This is on top of the heavy rainfall that has already accumulated across this area. So, flooding is a significant concern and those of you in this area should monitor local flood watches and warnings and take appropriate action if necessary.

Now, my opinion is that there is medium-high chance that this will regain at least tropical depression status during Monday as it tracks just offshore of the coast of Alabama and Mississippi. Environmental conditions are pretty favorable in this area and it may not take very long for it to intensify to tropical storm strength. Now, if this system tracks westward into southeast and southern Louisiana on Tuesday, then I think we’d be looking at a low to moderate tropical storm. Now, if this system take a slightly further south track like the 06 UTC GFS model is suggesting, then we may be looking at something stronger as it would have an additional 24 to 36 hours over favorable environmental conditions. All interests along the upper Texas coast, the Louisiana coast, the Mississippi coast and the Alabama coast should keep close tabs on this system. Needless to say, I will be monitoring Ex-Tropical Depression 5 very closely and will keep you all updated.
Member Since: Posts: Comments:
2657. xcool


cv
Member Since: September 26, 2009 Posts: 2 Comments: 15603
Quoting Levi32:


Ya and this storm will more than likely be coming in way too far north to get into the gulf.


This just might be the Big Apple storm that no one wants. That would be bad. Way to early to forecast that yet.......i would still favor a more southerly route tho.
Member Since: Posts: Comments:
2655. Drakoen
Quoting MississippiWx:
00z GFS takes ex-TD5 down to 1005mb before making landfall in Southern Louisiana. It certainly looks like the Florida Panhandle, Lower Alabama, South Mississippi and Central and Southern Louisiana will end up getting a wash out from this system. I'm afraid some will have some serious flooding issues to deal with and this could be the first damaging effects from the 2010 hurricane season in the United States.


Member Since: Posts: Comments:
I wonder if NOAA and NHC will ever use the word hyper again....not saying yet we won't have a busy season yet......but, the word hyper may have been on the extreme.
Member Since: Posts: Comments:
00z GFS takes ex-TD5 down to 1005mb before making landfall in Southern Louisiana. It certainly looks like the Florida Panhandle, Lower Alabama, South Mississippi and Central and Southern Louisiana will end up getting a wash out from this system. I'm afraid some will have some serious flooding issues to deal with and this could be the first damaging effects from the 2010 hurricane season in the United States.
Member Since: Posts: Comments:
Quoting xcool:


00z gfs


How strong is that and is it going west towards Texas or through LA only?
Member Since: July 2, 2009 Posts: 0 Comments: 2811
2651. Levi32
Quoting MississippiWx:


Positive 500mb height anomalies that far north would hopefully and more than likely not allow a Cape Verde system to make it into the Gulf. It would curve before making it there.


Ya and this storm will more than likely be coming in way too far north to get into the gulf.
Member Since: Posts: Comments:
Quoting CybrTeddy:


Evening all! Yup, appears so, and good model support for a Cape Verde system.


Ya i seen that as well...looks like the CV system nearly every model supports as well...looks to be a rather healthy thingy too.
Member Since: Posts: Comments:
2649. xcool


00z gfs
Member Since: September 26, 2009 Posts: 2 Comments: 15603
2648. KEEPEROFTHEGATE (Mod)
well good morning its aug 15 on the east coast here is the updated numbers for the rest of the season

ATLANTIC SEASON NUMBER OUTLOOK

TOTAL STORMS 12 TO 14
TOTAL HURRICANES 6 TO 8
TOTAL MAJORS 4 TO 6
TOTAL CAT 5's 1 TO 3
Member Since: Posts: Comments:
Quoting xcool:


How intense does this model show EX-05L to be?
Member Since: Posts: Comments:
Quoting Levi32:
This is what you want to watch out for. The closed height line at 500mb near the Bahamas represents the hurricane on the ensemble mean, sitting right underneath the big positive 500mb height anomaly which is centered north of New York State. That pattern means the hurricane makes landfall on the US east coast. If the trough gets out of there in time for the ridge to build in like that, we'll have to look out. At this point it's too far out to really say and it could go either way, but it should definitely be watched.

18z GFS ensemble mean 500mb height Day 12:



Positive 500mb height anomalies that far north would hopefully and more than likely not allow a Cape Verde system to make it into the Gulf. It would curve before making it there.
Member Since: Posts: Comments:
2645. Drakoen
If we look at the GEFS 12z spaghetti plots of the 540dm and the 582dm height contours we can see quite a few models show the dip off the eastern seaboard while the cyclone is northeast of the Lesser Antilles.


Member Since: Posts: Comments:
2644. Levi32
This is what you want to watch out for. The closed height line at 500mb near the Bahamas represents the hurricane on the ensemble mean, sitting right underneath the big positive 500mb height anomaly which is centered north of New York State. That pattern means the hurricane makes landfall on the US east coast. If the trough gets out of there in time for the ridge to build in like that, we'll have to look out. At this point it's too far out to really say and it could go either way, but it should definitely be watched.

18z GFS ensemble mean 500mb height Day 12:

Member Since: Posts: Comments:
Quoting TampaSpin:
EVENING ALL! Sure looks like Ex-td5 is gonna make that loop.....could be interesting times coming for the Northern Gulf Coast States!


Evening all! Yup, appears so, and good model support for a Cape Verde system.
Member Since: July 8, 2005 Posts: 259 Comments: 23016
EVENING ALL! Sure looks like Ex-td5 is gonna make that loop.....could be interesting times coming for the Northern Gulf Coast States!
Member Since: Posts: Comments:
2640. xcool
Member Since: September 26, 2009 Posts: 2 Comments: 15603
By the way, if a tropical system ends up forming in the Northern Gulf, the GFS picked up on this while TD5 was still west of Florida. A lot remains to be seen, but it could be a big early win for the new GFS. Also, if the Cape Verde hurricane forms off of Africa this week, it would have sniffed it out before the European for a second time.

Who knows if both things verify, but that would be huge for the new version of the GFS.
Member Since: Posts: Comments:
2638. Drakoen
Quoting MississippiWx:


With higher pressures over the Plains, a trof would have to go up and over the ridge before diving south any, which would put it at a higher latitude once it entered the Atlantic. It might be too far north to recurve a hurricane if the hurricane stays through the Caribbean.


The would be the case if the trough preceded the ridge.
Member Since: Posts: Comments:
Ex-05L going just south of Louisiana on the 00z run of the GFS.
Member Since: Posts: Comments:
2636. xcool
l
Member Since: September 26, 2009 Posts: 2 Comments: 15603
2635. JLPR2
Well I'm off to bed early today, goodnight everyone!
Member Since: Posts: Comments:
2634. Drakoen
Member Since: Posts: Comments:
Quoting Drakoen:


Right. And if you look over the Plains region you see increasing heights there.


With higher pressures over the Plains, a trof would have to go up and over the ridge before diving south any, which would put it at a higher latitude once it entered the Atlantic. It might be too far north to recurve a hurricane if the hurricane stays through the Caribbean.
Member Since: Posts: Comments:
2632. xcool
Member Since: September 26, 2009 Posts: 2 Comments: 15603
Quoting MiamiHurricanes09:
I feel confident in saying that we will see Danielle and Earl this coming week.


I'm gaining more confidence that we will see Danielle in the Northern Gulf.
Member Since: Posts: Comments:
GFS going much further south in the 00z run. The image below is at 42 hours:

Member Since: Posts: Comments:
2629. Drakoen
Quoting Twinkster:



Interesting so not your typical negative NAO pattern. So if that trough does verify than it is all timing. How far west it can go before feeling weakness caused by trough


Right. And if you look over the Plains region you see increasing heights there.

East of the Plains ridge you find downstream troughing. Foldover ridging.
Member Since: Posts: Comments:
Mississippi, I've been trying to track it via pressure and wind and it seems to be diving South. It's hard to pinpoint because it is in an area with few data stations.
Member Since: Posts: Comments:
I feel confident in saying that we will see Danielle and Earl this coming week.
Member Since: Posts: Comments:
GFS is trending farther south with ex-TD5 on the 00z run.
Member Since: Posts: Comments:
GFS 00Z at 36 hours



Member Since: Posts: Comments:

Viewing: 2675 - 2625

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 | 61 | 62 | 63 | 64 | 65 | 66Blog 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.