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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1.58pm There is huge amounts of silt and liquefaction is bubbling up around people's legs. People are getting out of their cars and abandoning them.
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Fatalities have happened... terrible quake took place about 2 hours ago..We all got families there... 10km southeast of christchurch...see for yourself..
BREAKING NEWS!!! TODAY TODAY JUST HAPPENED!!!
Two buses were also crushed by falling buildings. There are also people trapped in buildings, Christchurch Airport is closed, Emergency has been registered as LEVEL 3 declared by Civil Defence....Aussies are coming to NZ??? to help?? we should have enough resources of our own? Fatalities could be worse this year. Phones down and Power down...the cathedral square was packed but everyone is ok so far. lots of rubble by the cathedral, cars crushed. lots of police with loudspeakers telling people to move to safer areas. Many citizens ringing friends and families to see if they are ok. Some lost their cars and had to walk. Telecom urged people not to make calls but no one listens. Hospitals in Christchurch are evacuated. contact agencies have been contacteded in christchurch to help those necessary. Report to nearest Civil defence post if you have suffered.(An Unknown amount of people were crushed in the the big red buses by fallen debri. (just heard that on the tv news now at 3.08pm today) now I am worried about schools and the children..Latimer Square looks like a war zone, people on stretches, cut, bleeding, search and rescue crews. a block away is a major fire, with helicopters dropping monsoon buckets. People are in an absolute state of shock. There are massive aftershocks happening and still happening. The roads are bent out of shape people are walking. lots of buildings are down and damaged. The scale of damage is far worse because this time people were out on the streets lots of people ...last years quake mostly everyone was home and asleep. and it happened 4am in the morning in Sept 2010... but this one happened round the lunchtime period today.


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new zealand news on the earthquake:
Link
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Quoting presslord:


Is that Catholic or Anglican?

The church was built to withstand quakes,
From this

to this
Member Since: September 30, 2007 Posts: 9 Comments: 15932
Okay, maybe it's Cathlican
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Member Since: Posts: Comments:
(sniff)
Member Since: August 13, 2005 Posts: 163 Comments: 25782
Quoting presslord:


Is that Catholic or Anglican?


Anglican
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Quoting presslord:


Is that Catholic or Anglican?

Anglican
Member Since: September 30, 2007 Posts: 9 Comments: 15932
Its a time of great stress and deeds of Human compassion and when uncommon valor becomes a common virtue.

Lives are in the balance and adrenalin is doing now what cant wait for machinery in some cases.

My thoughts go out to the affected in NZ and those folks are going to need a lotta help real fast like.

Austrailia will be the lead as they are close and Reliefweb reports ar claxoning in my inbox now.

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Quoting AussieStorm:

Image from inside the Christchurch Cathedral


Is that Catholic or Anglican?
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Quoting PcolaDan:


And I think you know a whole lot of us appreciate the effort.

Image from inside the Christchurch Cathedral
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Quoting AussieStorm:

Oh, I didn't realise that was directed at me, Was to busy trying to give everyone here info on the Christchurch Quake.
Whatever floats his boat and boosts his ego.


And I think you know a whole lot of us appreciate the effort.
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Member Since: September 30, 2007 Posts: 9 Comments: 15932
Quoting twincomanche:


Beam me up Scottie. There's no intelligent life down here. I'm gone for the night. The giant ego reigns.

Oh i think you have the giant ego... goodbye
Member Since: September 30, 2007 Posts: 9 Comments: 15932
Quoting PcolaDan:


Never did I say otherwise. Happens all the time

I will say it more slowly since you missed it the first two times.
R
E
S
P
E
C
T

Aussie has earned it. "long respected blogger", is what I said.
Don't be so myopic in your reading and understanding.

Oh, I didn't realise that was directed at me, Was to busy trying to give everyone here info on the Christchurch Quake.
Whatever floats his boat and boosts his ego.
Member Since: September 30, 2007 Posts: 9 Comments: 15932
Quoting twincomanche:


Beam me up Scottie. There's no intelligent life down here. I'm gone for the night. The giant ego reigns.


And still no answer as to who you were before, or if you were banned. Just another blissful retort.
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Quoting AussieStorm:
I am about to turn off my Stream. ABC News 24 has the same stream here, Better quality sound and video.


Thanks Aussie. That one works here in US.
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Member Since: April 14, 2007 Posts: 8 Comments: 5167

Quoting AussieStorm:
Try this stream
Link

This link works, Aussie, but there is a lot of latency, even on low quality settings. At least we can get something. Thanks! Best to you and to all there.

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I am about to turn off my Stream. ABC News 24 has the same stream here, Better quality sound and video.
Member Since: September 30, 2007 Posts: 9 Comments: 15932
Quoting twincomanche:


A new person making their first post if it makes sense is as valuable as a old timer making their one thousandth post. Don't be so damn arrogant that you think that since you have been here since grass started to grow that your opinion is any more valuable than anyone else.


Never did I say otherwise. Happens all the time

I will say it more slowly since you missed it the first two times.
R
E
S
P
E
C
T

Aussie has earned it. "long respected blogger", is what I said.
Don't be so myopic in your reading and understanding.
Member Since: August 22, 2008 Posts: 12 Comments: 6010
caneswatch those are the DEPTHS he's got highlighted, not the mag

mag is the number after MAP

and Luzon phillipines adds thier own 5.3, but it's really deep

dear God hear us
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Quoting PcolaDan:


Aftershocks seem to be getting deeper.

MAP 5.5 2011/02/22 01:50:29 -43.588 172.734 9.6 SOUTH ISLAND OF NEW ZEALAND
MAP 5.6 2011/02/22 00:04:18 -43.580 172.798 6.7 SOUTH ISLAND OF NEW ZEALAND

MAP 6.3 2011/02/21 23:51:43 -43.600 172.710 5.0 SOUTH ISLAND OF NEW ZEALAND


9.6? That's not good........
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hi ,preslord ,dont forget ask for help to your good friend with FEMA ,
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Pcola...I know zilch about geological tectonics in that area...but Damn that's a crack, an angry living crack...

prayers for those scared people in NZ, I understand that fear
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Quoting JohnTucker:
SC sending help to Chch

Timaru Hospital and Bidwill Hospital are preparing to help Christchurch with casualties following today's earthquake as another powerful aftershock hit the region.

Timaru emergency services are unaware of any damage in South Canterbury and are preparing to send staff north to assist.

At Timaru Hospital, an incident operations centre has been set up.


SC is South Canterbury.

There are a few hospitals in CC. Im not sure which one had to be evacuated.

ChristChurch Hospital has been evacuated
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2.55pm – There are reports 60 percent of Lyttelton has been virtually demolished.

Live updates.
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our hearts to those struggling with the quate!!
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This link is now working.
Link
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Quoting Patrap:
#211.


Fascinating.

Wrong,,but still fascinating.


800,000 Year Record of Carbon Dioxide (CO2) Concentrations





And, according to the latest number of 391.19ppm, we're still inside that blue dot.
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Quoting cchsweatherman:


I'll be ready to help get involved once again down here in South Florida if needed.


Great! Thanks!! let's see how it all unfolds...
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Quoting twincomanche:


You people are so tiresome. Get over yourselves.


So, no answer? And a repeat of a statement I made for you. Original.
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Quoting AussieStorm:

Will do
Wouldn't be surprised if there was amputees like Haiti


good point
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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


Aftershocks seem to be getting deeper.

MAP 5.5 2011/02/22 01:50:29 -43.588 172.734 9.6 SOUTH ISLAND OF NEW ZEALAND
MAP 5.6 2011/02/22 00:04:18 -43.580 172.798 6.7 SOUTH ISLAND OF NEW ZEALAND

MAP 6.3 2011/02/21 23:51:43 -43.600 172.710 5.0 SOUTH ISLAND OF NEW ZEALAND
Member Since: August 22, 2008 Posts: 12 Comments: 6010
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!


I'll be ready to help get involved once again down here in South Florida if needed.
Member Since: April 14, 2007 Posts: 8 Comments: 5167
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.
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.