Dakotas blizzard adds to extreme spring flooding risk

By: Dr. Jeff Masters , 2:13 AM GMT on February 21, 2011

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Heavy snows in excess of six inches have piled up over much of South Dakota, North Dakota, Montana, Wisconsin, and Minnesota today, with a storm maximum of 16 inches reported at Midland, South Dakota. This is bad news for residents in flood-prone areas of the Upper Midwest, as the new storm has added more than another half inch of melted rainfall equivalent to a snowpack that already had a record water content. When all that snow melts in late March, we can expect another spring of major and possibly record flooding for North Dakota, South Dakota, Minnesota, or the Upper Mississippi River north of St. Louis, according to the National Weather Service (NWS). Their February Spring Flood Outlook released last week warned: "Heavy autumn rains and above average water content in the snow pack throughout the North Central U.S. have produced a high risk of moderate and major flooding for the Spring of 2011. Areas of greatest concern include the Red River of the North in North Dakota and Minnesota, Devils Lake in North Dakota, the James River and Big Sioux River in South Dakota, and areas along the Upper Mississippi River including Minnesota, Wisconsin, Iowa, Illinois and Missouri.

Heavy late summer and autumn precipitation (twice the normal amount since October in parts of North Dakota and Minnesota) have soils saturated and streams running high before the winter freeze-up. Another winter of above average snowfall has added water to the snow pack on top of the frozen saturated soils in the North Central US. NWS models show this snowpack containing a water content ranked in the 90 to 100 percentile when compared to a 60 year average. These factors have combined to create some of the highest soil moisture contents of the last century. "



Figure 1. North Central U.S. flood risk. Image credit: NWS. The outlook will be updated on February 24, and a final outlook issued March 17.

There is a huge amount of snow on the ground in North Dakota along the tributaries of the Red River, thanks to fall precipitation that was 150% - 300% of normal, and winter snows that have dumped up to 400% more precipitation than usual. If one were to melt this snow, it would amount to 4 - 5 inches of rain. If heavy rains occur at the same time that the snow melts, there is the potential for the greatest flood in history to affect the cities of Fargo and Grand Forks, the largest and third largest cities in North Dakota. NWS is giving a 20% chance that Fargo will see its greatest flood in history, and a 10% chance for Grand Forks.

The situation is similar in Minnesota, which has received about double its normal precipitation over the past 3 to 4 months. Snow depths are generally around 18 inches in the Upper Mississippi watershed, with a high water content. If one were to melt this snow, it would amount to 3.5 - 5.5 inches of rain, which ranks among the wettest snow packs in the 60-year record. NWS is giving a 15% chance that St. Paul will see its highest flood in history this spring.

In South Dakota, heavy snows this winter have also left a snowpack with a high water content, and NWS is predicting a 30% chance that the the James River at Huron, SD and the Big Sioux River at Brookings, SD will reach their highest flood heights in history.


Figure 2. The snow water equivalent of the Upper Midwest's snowpack as of February 18, 2011. Large sections of Minnesota and North Dakota have the equivalent of 3.9 - 5.9 inches of rain (purple colors) stored in their snowpack. Image credit: NWS/NOHRSC.

When will all this flooding occur? Generally, late March through mid-April is the time when the big spring melt occurs. The record 2009 Red River flood peaked on March 28 in Fargo. The great 1997 Red River flood that devastated Grand Forks, causing $3.5 billion in damage, crested on April 18. St. Paul's greatest flood in history crested on April 19, 1965.

I'll have a new post Tuesday or Wednesday.

Jeff Masters

Blinding snowstorm hits Detroit area (MichiganSnowLvr)
The Detroit area was hit with a blinding snowstorm this afternoon and evening, with near zero visibility and thunder/lightning, as the snowfall piles up quickly and deeply.
Blinding snowstorm hits Detroit area

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308. Levi32
2:16 AM GMT on February 22, 2011
By the way, according to Jesse Ferrell on Facebook, Joe Bastardi was not fired from Accuweather, but that's all he knows about it. In other words, it sounds like he is leaving of his own accord, or something along those lines.
Member Since: November 24, 2005 Posts: 635 Comments: 26654
307. AussieStorm
2:15 AM GMT on February 22, 2011
Quoting aquak9:
love to you, surf

I know this- a 6.8 mag at 15 miles deep will bounce you offa a very heavy couch. I can't imagine a 6.3 at only 4 miles deep.

love surfmom

Quake struck at 12:51pm
Member Since: September 30, 2007 Posts: 9 Comments: 15940
306. aquak9
2:13 AM GMT on February 22, 2011
love to you, surf

I know this- a 6.8 mag at 15 miles deep will bounce you offa a very heavy couch. I can't imagine a 6.3 at only 4 miles deep.

love surfmom
Member Since: August 13, 2005 Posts: 166 Comments: 26050
305. AussieStorm
2:10 AM GMT on February 22, 2011
Quoting presslord:
Aussie....Would you please keep a particular lookout for needs involving people with disabilities in New Zealand? If you come across anything please shoot me a WU mail...Thanks!

Will do
Wouldn't be surprised if there was amputees like Haiti
Member Since: September 30, 2007 Posts: 9 Comments: 15940
303. presslord
2:09 AM GMT on February 22, 2011
Aussie....Would you please keep a particular lookout for needs involving people with disabilities in New Zealand? If you come across anything please shoot me a WU mail...Thanks!
Member Since: August 13, 2007 Posts: 0 Comments: 10492
302. PcolaDan
2:07 AM GMT on February 22, 2011
Quoting RecordSeason:
273:

Yes.

It's very close to the surface, making it exponentially more damaging per unit energy released.



GNS says acceleration was a full 1G, against 0.8G for September, which equates to a 25% higher speed of movement at ground level.
Member Since: August 22, 2008 Posts: 12 Comments: 6010
301. surfmom
2:06 AM GMT on February 22, 2011
Quoting aquak9:
post 260

aussie, it says only folks in australia can see it

and I apologize for the self-centeredness of many americans, we're not all like that, I promise

your home has been in a lotta my prayers, just wanted you to know (hangs head in shame)


Me Too!!!
Member Since: July 18, 2007 Posts: 30 Comments: 26536
My Ustream, streaming live news from Christchurch.








Live Videos by Ustream

My wife just came home from work. I gave her a massive hug.
I think all of us should do the same to our loved ones.
Member Since: September 30, 2007 Posts: 9 Comments: 15940
Quoting twincomanche:


I'm sure his opinions are much more valuable since he has been here longer. No one has to do anything I think, however I am entitled to my opinion. What we think about world events are probably better left to a blog dedicated to that IMHO. Natural events have always been posted here. I have been here longer than you know.


His opinions are more valuable because he has earned RESPECT, (you must have skipped over that word on my original post). And if you have been here so long, why are you not using that user name? Was it banned?
Member Since: August 22, 2008 Posts: 12 Comments: 6010
thanks Aqua
Member Since: July 18, 2007 Posts: 30 Comments: 26536
Quoting cchsweatherman:


Unfortunately, its a byproduct of freedom of speech. People are free to talk about what they want as long as it falls within the rules, whether we like it or not. I appreciate your passion into this tragedy, but some may not care as much as you.

yes they care about some guy on a rival website and not about people dying
Member Since: September 30, 2007 Posts: 9 Comments: 15940
Quoting Levi32:


Forecasting is exactly what predicting global temperature is. The only problem here is getting involved in a politically polluted issue on the side that is most ridiculed. When has that ever turned out good for anybody.



Maybe it's because they deny everything you throw at them.

Global Warming has been proven to be happening. Humans have been proven to be warming the planet. Anyone who thinks otherwise is in a state of denial.

Time to stop sympathizing with them, Levi.
Member Since: Posts: Comments:
Quoting Levi32:
JB is a brilliant meteorologist. People like him are completely entitled to their opinions on AGW, and that should never be a reason to fire him. His long-range forecasts are forecasts that nobody else dares to make, and he's right a good portion of the time. His main focus in his job has nothing to do with AGW, but weather forecasting for the U.S. and Europe, which he has done a very fine job of. JB is only subjective in some aspects of his AGW beliefs, but as a meteorologist he is one of the best in the business. Tarnishing his name here only tarnishes yours, as many people speaking in this blog have shown tremendous inability to be objective and fair.


A "brilliant meteorologist"? I beg to differ. First, it was absolutely necessary for Accuweather to fire him after his wrongful attack on NSIDC. If Accuweather had not fired him, then they would be standing by falsified accusations. Maybe Accuuweather can now gain some credibility now that he is gone. He doesn't know how to read basic maps, or know the difference between an anomaly and standardized anomaly. Farthest thing from brilliant, in any sense of the word. I terribly surprised when I saw his video comparing the temperature anomalies to the sea ice extent.

You are mistaken in that he was fired for his opinion on AGW. His general lack of respect for the NHC, NWS, NSIDC and possibly and probably any other environmental agency opposed to his views is what led to his downfall.


Member Since: Posts: Comments:
Quoting weatherboy1992:
RecordSeason makes several important errors. First of all he forgets that half the time our roadways are in the night half of Earth, and therefore absorb no solar radiation during that time.

So his estimate falls in half.

RecordSeason also assumes in reaching his figure that any area covered by a road absorbed no radiation before it was paved. Not the case.

The Earth's Bond Albedo, is .306, or 30.6%. The bond albedo includes earth's reception and reflection/absorption of all electromagnetic radiation it receives not just visible light or IR.

The proper way to handle absorption by roads is to compare the net difference in absorption of radiation by the surface before and after it was paved. The earth as a whole absorbs nearly 70% of all radiation it receives.

So after falling by a half, RecordSeason's estimate falls by more than 2/3rds.

His estimate for net additional absorption by roads is off by more than a factor of 6.

It's not 21.55 terawatts. It is 3.30 terawatts.

And forcing by greenhouse gasses therefore represents 462 times net additional absorption by roads, at current greenhouse gas levels.

Will probably be 500 x roads by 2015.


Additionally, he's ignoring concrete and assuming it's all asphalt.

Additionally, he's ignoring the fact that the even if it is day time, it could also be cloudy.

Additionally, he's ignoring the fact that even when it is daytime, the sun is only shining at "full power" during the solar noon, the rest of the day it is at a lower level of energy.

Additionally, he's ignoring the fact that some roads are in tunnels, and others are on the sides of mountains meaning half the day they receive little to no solar radiation.

Additionally, he's assuming all these roads are at the same latitude.

Additionally, he's assuming that these roads are never covered by something, like say a car, possibly? Do cars drive on roads?





The list goes on.

Record Season, I agree with you, we have certainly altered the surface of our planet. And certainly in the direction that would cause more warming.

BUT, your method of calculating is not correct, because it leaves out soooo many variables.
Member Since: Posts: Comments:
only decent new zealand seismo I could find quick

still cracking, I see a five and maybe a six hard jolt...

I am so sorry aussie for your neighbors, the vid and sound on your ustream is frightening

Member Since: August 13, 2005 Posts: 166 Comments: 26050
Quoting AussieStorm:

But people here arguing about some guy on a rival website quitting is just stupid


Unfortunately, its a byproduct of freedom of speech. People are free to talk about what they want as long as it falls within the rules, whether we like it or not. I appreciate your passion into this tragedy, but some may not care as much as you.
Member Since: April 14, 2007 Posts: 8 Comments: 5169
Try this stream
Link
Member Since: September 30, 2007 Posts: 9 Comments: 15940
papua new guinea seismo

big slapping crack there


Member Since: August 13, 2005 Posts: 166 Comments: 26050
Quoting cchsweatherman:


Even though I share your sentiment as I have shown, we can't do anything beyond send our best wishes and report the news as we receive it at this point.

But people here arguing about some guy on a rival website quitting is just stupid
Member Since: September 30, 2007 Posts: 9 Comments: 15940
Quoting AussieStorm:
What the HELL is wrong with you people.... People are dying in Christchurch and Libya and your all arguing about a guy quitting a rival website. God help us.


Even though I share your sentiment as I have shown, we can't do anything beyond send our best wishes and report the news as we receive it at this point.
Member Since: April 14, 2007 Posts: 8 Comments: 5169
Quoting twincomanche:


Should we be talking about that here? I think not.


About what's going on in Christchurch, yes. Earthquakes are natural, and like this one, they're deadly. Libya, no. That's for elsewhere.

You should've thought twice before you said no to both events.
Member Since: October 8, 2008 Posts: 14 Comments: 4553
Quoting AussieStorm:


Wtahc my Ustream.... Link


Already on it and forwarded link to my volcano friends.
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Quoting twincomanche:


Should we be talking about that here? I think not.


So, the new kid on the block is the one who decides what is discussed here, while the long respected blogger who keeps us informed of happenings in the southern hemisphere is to be ignored?

I think not.

Get over yourself.
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Quoting Levi32:


Forecasting is exactly what predicting global temperature is. The only problem here is getting involved in a politically polluted issue on the side that is most ridiculed. When has that ever turned out good for anybody.

Why do you think it's most ridiculed?

According to most the people on that side, the side who "ridicules the most" are also fun loving hippie tree huggers.

Yet you are right that they are the most ridiculed.


hmmm, let's ponder this together.



Maybe it's because they deny everything you throw at them.

Global Warming has been proven to be happening. Humans have been proven to be warming the planet. Anyone who thinks otherwise is in a state of denial.

Time to stop sympathizing with them, Levi.
Member Since: Posts: Comments:
post 260

aussie, it says only folks in australia can see it

and I apologize for the self-centeredness of many americans, we're not all like that, I promise

your home has been in a lotta my prayers, just wanted you to know (hangs head in shame)
Member Since: August 13, 2005 Posts: 166 Comments: 26050
Quoting PcolaDan:


Only available in Australia Aussie. Thanks anyway.


Watch my Ustream.... Link
Member Since: September 30, 2007 Posts: 9 Comments: 15940
Quoting AussieStorm:
Image of Christchurch Quake


Thats an impressive seismic signature right there. Can tell without the reported depth that this occurred at a very shallow depth which makes the earthquake exponentially worse.
Member Since: April 14, 2007 Posts: 8 Comments: 5169
Quoting twincomanche:


Should we be talking about that here? I think not.

Should we be talking about what... Earthquakes or rivals
Member Since: September 30, 2007 Posts: 9 Comments: 15940
Quoting AussieStorm:
Watch Live News from new Zealand here.... Link


Only available in Australia Aussie. Thanks anyway.
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Quoting AussieStorm:
What the HELL is wrong with you people.... People are dying in Christchurch and Libya and your all arguing about a guy quitting a rival website. God help us.


Just posted link to your Ustream on the volcano blog I visit.

Yea, some peoples priorities!
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Image of Christchurch Quake
Member Since: September 30, 2007 Posts: 9 Comments: 15940
Quoting Levi32:


Forecasting is exactly what predicting global temperature is. The only problem here is getting involved in a politically polluted issue on the side that is most ridiculed. When has that ever turned out good for anybody.


Never, and i'm afraid it will remain political for a long time.
Member Since: October 8, 2008 Posts: 14 Comments: 4553
What the HELL is wrong with you people.... People are dying in Christchurch and Libya and your all arguing about a guy quitting a rival website. God help us.
Member Since: September 30, 2007 Posts: 9 Comments: 15940
Quoting caneswatch:


I agree. Those who are experts have shown themselves to be what they are. JB was a good expert at forecasting, yes, but that's the subject he should have stayed on.


Forecasting is exactly what predicting global temperature is. The only problem here is getting involved in a politically polluted issue on the side that is most ridiculed. When has that ever turned out good for anybody.
Member Since: November 24, 2005 Posts: 635 Comments: 26654
Watch Live News from new Zealand here.... Link
Member Since: September 30, 2007 Posts: 9 Comments: 15940
Quoting Levi32:


Oh. So we're not allowed to study or consider the research of anything outside of the "consensus?" I didn't know that. I guess the consensus must always be right. I'll be sure to consult them and only them from now on.


Nice sarcasm LOL. Everything has to be studied outside of the consensus no matter what. If it wasn't there, the "consensus" would be wrong sometimes and we would be believing lies.
Member Since: October 8, 2008 Posts: 14 Comments: 4553

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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.