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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BPOilSpillStillScrewingUptheGulf

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RitaEvac:

I just LOVE it when the state I live in gets in the news for not-so-great reasons.

Also, on the school topic.. private schools are probably doing GREAT business now. Education should be the LAST thing cut, along with healthcare. Not the first.
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And add in the weather in all the chaos
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Wisconsin may start rioting if the governor there doesn't side with them about the unions, that might get ugly, then in TX they're are supposed to cutback major assets in the school industry which would mean having 50 kids in one classroom due to teacher layoffs, funding cut, loss of athletics, who knows maybe rioting and civil war breaking out on American soil soon, just in time for good ol 2012
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I'm more concerned about this years server weather,and hurricane season now.It's seeming to much like a 2008 repeat.
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Quoting RecordSeason:
This would likely reduce an additional 1/7th of the nation to instant poverty/homelessness either directly or indirectly.

The corporate-led side of the aisle is doing a good job of that without any mathematical trickery needed.
Member Since: November 8, 2009 Posts: 4 Comments: 13805
It's suppose to snow in D.C tonight.But am I excited?.Hellll no.Ain't nothing happening,and ain't nothing gonna stick to the ground.I've been excited to many times this year.But now I've given up.
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Quoting RitaEvac:
One of the most ridiculous temperature map contrasts I've ever seen by the GFS

Amen to that. A 40C+ difference over 400-ish miles? Yeah, right.
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Quoting SQUAWK:


I think that means two thousand billion. If that is the case, it is a bunch of money. Although, I can't imagine why they just didn't say 2 trillion.

Yeah, I misread it. Thanks for pointing that out.
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Quoting SQUAWK:


Good morning. Looks like it will be getting busy in here soon. Should be interesting. How are things in your area looking?
Not good unfortunately..The plateau will probably be in the slight to moderate risk area. I also noticed that there is plenty of low level moisture as the system moves east...The SPC has this to say...Link
Member Since: September 27, 2007 Posts: 1 Comments: 22712
Quoting hydrus:
LOl..I wuz wonderin dat too...Good morning Squawk...Severe weather is a comin.


Good morning. Looks like it will be getting busy in here soon. Should be interesting. How are things in your area looking?
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Quoting SQUAWK:


I think that means two thousand billion. If that is the case, it is a bunch of money. Although, I can't imagine why they just didn't say 2 trillion.
LOl..I wuz wonderin dat too...Good morning Squawk...Severe weather is a comin.
Member Since: September 27, 2007 Posts: 1 Comments: 22712
Quoting bappit:

Actually two billion is not that much anymore as disasters go.


I think that means two thousand billion. If that is the case, it is a bunch of money. Although, I can't imagine why they just didn't say 2 trillion.
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Wikipedia:

Woolworths Limited is the largest retail company in Australia and New Zealand. Although named after the F.W. Woolworth brand, it has no relation

The name on the draft prospectus drawn up by Cecil Scott Waine was "Wallworths Bazaar" %u2013 a play on the F.W. Woolworth name (the owner of the Woolworth's chain in the United States and United Kingdom). However, according to Ernest Robert Williams, Percy Christmas dared him to register the name Woolworths instead, which he succeeded in doing after finding out the name was available for use in New South Wales. Accordingly, Woolworths Ltd in Australia has no connection with the F.W. Woolworth Company in the United States.
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Quoting Skyepony:
Australia~ At around 3.30pm this afternoon, Karratha CBD and parts of Bulgarra were hit by a tornado. Witnesses describe four small tornadoes forming into one large tornado near TV hill, crossing Millstream Road blowing over a four wheel drive and caravan. The caravan was totally destroyed. The tornado continued down Gregory way, uprooting large trees, and tearing off roofs. Boats were thrown into the air and onto roof of houses. Local business proprietor Kylie Boyd suffered severe damage, with her partners ute being blown on it's side, and her parents caravan being completely torn to shreds. The storm continued over Hedland place, smashing down walls and tearing off signage and roof sheeting along Hedland place. The All Seasons bar had sections of walls missing, nearby at Woolworths and Target large sections of roof were missing. People inside the shopping centre lay on the ground while gusts of wind blew through the centre from one end through to Kmart at the other end. Many vehicles were damaged, some with every window blow out. The carnage continued to the Karratha swimming pool, bending over steel poles, shredding fences and shade sails. Karratha Vet also suffered severe damage, blowing out most windows and tearing off the roof. It has also been reported that cars were blow over at Pilbara Motor Group, and along Crane Circle. Meanwhile, most of the Pilbara Coast is on alert for Tropical Cyclone Carlos, expected to hit Karratha later tonight as a category two system.

I didn't even know Woolworths still existed. This is the second one I've seen damaged in another country in as many days. Ute is some sort of car?

Ute

Caravan

Woolworths is a major grocery chain here In Australia, also know as Safeways in Victoria.
Member Since: September 30, 2007 Posts: 9 Comments: 15979
Quoting Inyo:
Our best hope to decrease floods like these lie not in huge infrastructure projects but in restoring and constructing wetlands, healthy riparian forests, and undeveloped flood plains that can absorb water during floods and let it out slowly later. Really, it's our only hope to decrease floods like this. Instead, though, we continue to remove wetlands, improperly manage forests, and put in place more concrete that makes flooding worse and worse over time. People blame global warming for increased flooding and that may be the case at times, but the strongest reason for increased floods is really just our abuse of the land.

Vermont has a lot of snow on the ground too. We are hoping for 'good sugaring weather' - sunny days with above freezing highs and below freezing lows. In addition to being great for maple syrup production, this leads to a slow chipping away at the snowpack instead of flooding.

That is very true. I am hoping there is a slow melt so flooding doesn't become much of an issue
Member Since: September 30, 2007 Posts: 9 Comments: 15979
89. Skyepony (Mod)
Australia~ At around 3.30pm this afternoon, Karratha CBD and parts of Bulgarra were hit by a tornado. Witnesses describe four small tornadoes forming into one large tornado near TV hill, crossing Millstream Road blowing over a four wheel drive and caravan. The caravan was totally destroyed. The tornado continued down Gregory way, uprooting large trees, and tearing off roofs. Boats were thrown into the air and onto roof of houses. Local business proprietor Kylie Boyd suffered severe damage, with her partners ute being blown on it's side, and her parents caravan being completely torn to shreds. The storm continued over Hedland place, smashing down walls and tearing off signage and roof sheeting along Hedland place. The All Seasons bar had sections of walls missing, nearby at Woolworths and Target large sections of roof were missing. People inside the shopping centre lay on the ground while gusts of wind blew through the centre from one end through to Kmart at the other end. Many vehicles were damaged, some with every window blow out. The carnage continued to the Karratha swimming pool, bending over steel poles, shredding fences and shade sails. Karratha Vet also suffered severe damage, blowing out most windows and tearing off the roof. It has also been reported that cars were blow over at Pilbara Motor Group, and along Crane Circle. Meanwhile, most of the Pilbara Coast is on alert for Tropical Cyclone Carlos, expected to hit Karratha later tonight as a category two system.

I didn't even know Woolworths still existed. This is the second one I've seen damaged in another country in as many days. Ute is some sort of car?
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Quoting RitaEvac:
One of the most ridiculous temperature map contrasts I've ever seen by the GFS
If this pans out, three big storms for the eastern half of the United States in less than two weeks..Severe weather will almost certainly be an issue....Link
Member Since: September 27, 2007 Posts: 1 Comments: 22712
One of the most ridiculous temperature map contrasts I've ever seen by the GFS
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Mighty clash of 2 airmasses... March 5th


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This could end up being a significant storm too...
Member Since: September 27, 2007 Posts: 1 Comments: 22712
84. Inyo
Our best hope to decrease floods like these lie not in huge infrastructure projects but in restoring and constructing wetlands, healthy riparian forests, and undeveloped flood plains that can absorb water during floods and let it out slowly later. Really, it's our only hope to decrease floods like this. Instead, though, we continue to remove wetlands, improperly manage forests, and put in place more concrete that makes flooding worse and worse over time. People blame global warming for increased flooding and that may be the case at times, but the strongest reason for increased floods is really just our abuse of the land.

Vermont has a lot of snow on the ground too. We are hoping for 'good sugaring weather' - sunny days with above freezing highs and below freezing lows. In addition to being great for maple syrup production, this leads to a slow chipping away at the snowpack instead of flooding.
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Quoting cat5hurricane:

YES!! :)
I like Busch beer. But it did taste a little better at that price...A severe weather outbreak is possible Thursday into Friday...
Member Since: September 27, 2007 Posts: 1 Comments: 22712
Quoting Orcasystems:
Scientists warn of $2,000bn solar ‘Katrina’

By Clive Cookson in Washington

Published: February 20 2011 17:50 | Last updated: February 20 2011 17:50

The sun is waking up from a long quiet spell. Last week it sent out the strongest flare for four years – and scientists are warning that earth should prepare for an intense electromagnetic storm that, in the worst case, could be a “global Katrina” costing the world economy $2,000bn.......

Actually two billion is not that much anymore as disasters go.
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Quoting Xyrus2000:


Yeah. And if you don't think about it makes even more sense.

"I'm trying to think but nothing happens."
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Perth Tropical Cyclone Warning Center
Tropical Cyclone Bulletin
TROPICAL CYCLONE DIANNE (16U)
9:00 PM WST February 21 2011
==========================================

At 8:00 pm WST, Tropical Cyclone Dianne, Category Two (980 hPa) located at 26.9S 102.6E, or 1130 km west southwest of Carnarvon and 1200 km west of Geraldton has 10 minute sustained winds of 50 knots with gusts of 70 knots. The cyclone is reported as moving south southwest at 12 knots.

Dvorak Intensity: T2.5/3.5/W2.0/24 HRS

Storm Force Winds
==================
40 NM from the center

Gale Force Winds
=================
120 NM from the center in

Forecast and Intensity
======================
12 HRS: 28.6S 101.9E - 45 knots (CAT 1)
24 HRS: 30.4S 102.3E - 35 knots (CAT 1)
48 HRS: 33.3S 102.7E - 30 knots (TROPICAL LOW)
72 HRS: 37.8S 103.7E - 30 knots (TROPICAL LOW)

Additional Information
=======================

Position based on satellite imagery and past movement. Enhanced satellite imagery shows substantially warmer cloud tops. Deep convection is displaced to the south of the LLCC conducive with approximately 10 knots of northerly shear over the system. Microwave imagery shows that the system is still reasonably well structured. TC Dianne is located over SSTs of about 24 deg C or less.

DT is becoming difficult to asign, however a shear pattern with less than 3/4 degree distance from the LLCC and the cold cloud gives 2.5. Over the last 24 hours TC Dianne has shown considerable weakening with the loss of it's eye and removal of deep convection from the systems centre, so MET=3.0 based on W+ [strong weakening] trend. PT=2.5 after adjusting MET down. FT is based on PT [which agrees with DT]. CI is held 1.0 higher at 3.5 with the expectation that TC Dianne may show renewed convective activity during the diurnally favourable overnight period, sustaining a weak category 2 system [maximum winds 50 knots] until Tuesday morning.

Latest SATCON intensity estimates have TC Dianne slightly stronger at 54 kt and ADT slightly weaker at 47 knots.

Forecast track continues to moves the system southwards over cooler SSTs. Increasing NW shear is also expected to develop over the system. Thus TC Dianne is expected to weaken to below TC intensity in about 24 hours time.

The next tropical cyclone bulletin from Perth Tropical Cyclone Warning Center on Tropical Cyclone Dianne will be issued at 19:00 PM UTC..
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Perth Tropical Cyclone Warning Center
Tropical Cyclone Advice #41
TROPICAL CYCLONE CARLOS (17U)
9:00 PM WST February 21 2011
===============================================

At 8:00 pm WST, Tropical Cyclone Carlos, Category One (988 hPa) located at 18.7S 119.3E, or 195 km north northeast of Port Hedland and 340 km northeast of Karratha has 10 minute sustained winds of 45 knots with gusts of 55 knots. The cyclone is reported as moving west southwest at 12 knots.

Gale Force Winds
===============
70 NM from the center in northwestern quadrant
90 NM from the center in southwestern quadrant
40 NM from the center in northeastern quadrant
40 NM from the center in southeastern quadrant

Dvorak Intensity: T3.0/3.0/D0.5/24 HRS

Tropical Cyclone Carlos is expected to continue moving in a general west southwest track roughly parallel to the Pilbara coast and gradually intensify overnight and during Tuesday.

GALES with wind gusts to 100 kilometres per hour may develop in coastal areas near Port Hedland later tonight extending west to Karratha Tuesday morning and then towards Exmouth later on Tuesday. There is the risk of DESTRUCTIVE winds with gusts exceeding 125 kilometres near Whim Creek early on Tuesday , then extending further west toward Onslow during Tuesday, possibly reaching Exmouth by late Tuesday.

On Wednesday gales may extend south to Cape Cuvier, possibly reaching as far south as Carnarvon by Wednesday evening.

Residents of Pilbara coastal towns are warned that tides may rise significantly above the high water mark as the cyclone moves down the coast, even if it doesn't cross the coast. DAMAGING WAVES and FLOODING of low lying coastal areas are possible particularly on Tuesday's high tide in the Karratha region.

HEAVY RAIN is expected to cause significant stream rises with possible localised flooding for Pilbara coastal streams overnight and during Tuesday. Most of the rainfall is to the west of the cyclone, so rainfall is expected to ease soon after the cyclone passes. Refer to the Flood Advice for the Pilbara [IDW39620].

Tropical Cyclone Watches/Warnings
====================================

A Cyclone WARNING is current for coastal areas from Wallal to Exmouth, extending to the adjacent inland Pilbara including Millstream.

A Cyclone WATCH is current for areas from Exmouth to Carnarvon, extending to adjacent inland areas including Nanutarra and Minilya Roadhouse.

Forecast and Intensity
====================
12 HRS: 19.9S 117.3E - 55 knots (CAT 2)
24 HRS: 21.0S 115.4E - 60 knots (CAT 2)
48 HRS: 23.4S 111.7E - 70 knots (CAT 3)
72 HRS: 25.7S 108.7E - 60 knots (CAT 2)

Additional Information
=======================

Tropical Cyclone Carlos is moving on a west southwest track towards the Pilbara coast. Deep convection is evident northwest of the centre but the system is battling 20 knots of easterly wind shear.

Dvorak estimates estimates range from 3.0 to 3.5 with FT/CI=3.0. SATCON at 11UTC is 52 knots [1-minute mean] with ADT lower and AMSU slightly higher. Offshore observations are reading around 40 knots well away from the system centre on the southern side. Final intensity estimate is 45 knots [10-min].

The forecast track persists steadily to the west southwest taking it very close to the Pilbara coast, possibly crossing the coast, under the influence of a middle-level ridge to the southeast. Model guidance indicates relatively high confidence in the consensus track due to low spread..

The current forecast indicates some intensification off the Pilbara coast. Despite high ocean heat content, moderate easterly shear should constrain intensification. Once clear of land in the longer term there is a better chance of intensification when shear eases though in th elonger term ocean heat content will begin to constrain the system.

Carlos presents a significant storm surge threat especially as tides are close to HAT in this region during the next few days. The shelf wave is likely to cause tides to rise above the high water mark regardless of whether the cyclone directly causes a storm surge on the coast.

The next tropical cyclone advice from Perth Tropical Cyclone Warning Center on Tropical Cyclone Carlos will be issued at 10:00 AM UTC..
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Fiji Meteorological Services
Tropical Cyclone Advisory #15
SEVERE TROPICAL CYCLONE ATU (11F)
0:00 AM FST February 22 2011
=======================================

At 12:00 PM UTC, Severe Tropical Cyclone Atu, Category Four (940 hPa) located at 19.0S 170.5E has 10 minute sustained winds of 90 knots. The cyclone was reported as moving south southeast at 6 knots. Position good based on multispectral infrared imagery with peripheral surface observations.

Hurricane Force Winds
======================
30 NM from the center

Storm Force Winds
===============
80 NM from the center in northeast quadrant
130 NM from the center in southeast quadrant
80 NM from the center in southwest quadrant
40 NM from the center in northwest quadrant

Gale Force Winds
===============
200 NM from the center in northeast quadrant
160 NM from the center in southeast quadrant
100 NM from the center in western semi-circle

Overall organization remains good. Eye partially cloud filled but still discernible. Eye warming and cloud tops cooling past 3 hours. Primary bands wrapping around low level circulation center. Outflow good to north and east but fair elsewhere. Sea surface temperature is around 29C. System lies along a weak sheared environment. System is being steered southeast by a northwesterly deep layer mean wind.

Dvorak assessment based on eye pattern with OW eye and LG surround yielding DT=5.0, MET=5.5, PT=5.0. Final Dvorak T number based on DT.

Dvorak Intensity: T5.0/5.5/S0.0/24HRS.
Global models move the system south southeast.

Forecast and Intensity
========================
12 HRS: 20.9S 171.3E - 90 knots (CAT 4)
24 HRS: 23.6S 172.6E - 90 knots (CAT 4)
48 HRS: 30.1S 177.8E - 85 knots (CAT 3)

The next tropical cyclone advisory from Fiji Meteorological Services will be issued at 20:30 PM UTC.
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Quoting sunlinepr:
The World’s Oldest Water? Link

ScienceDaily (Feb. 19, 2011) — New evidence bolsters the notion that deep saline groundwaters in South Africa's Witwatersrand Basin may have remained isolated for many thousands, perhaps even millions, of years.

Interesting post. Thanks.
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.
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Member Since: September 30, 2007 Posts: 9 Comments: 15979
Quoting aquak9:
I'm trying to remember some other specific benchmarks from the early and mid 80's, but I was young then and wouldn't have been paying much attention to everything that didn't directly concern me.

6-pak of Miller High Life for $1.99
And a case of Busch for 6 bucks...:)
Member Since: September 27, 2007 Posts: 1 Comments: 22712
This is the worst senario for TC Carlos. An Intensifying Cyclone, it's core over warm water, rain bands, bad side on land. Going to see very high rainfall amount from TC Carlos on the NW W.A coast. Possible more flooding in a region that's still recovering from record flooding in December.
TC Carlos

TC Carlos Rain Rate
Member Since: September 30, 2007 Posts: 9 Comments: 15979



Image above: The STS-133 crew members pose for a group photo on the shuttle landing facility following their arrival aboard T-38 jets. From left, are Mission Specialists Nicole Stott, Michael Barratt, Steve Bowen and Alvin Drew, Pilot Eric Boe, and Commander Steve Lindsey. Bowen replaces astronaut Tim Kopra, who was injured in a bicycle accident in January 2011. Photo credit: NASA



During space shuttle Discovery's final spaceflight, the STS-133 crew members will take important spare parts to the International Space Station along with the Express Logistics Carrier-4.

Steve Bowen replaced Tim Kopra as Mission Specialist 2 following a bicycle injury on Jan. 15 that prohibited Kopra from supporting the launch window. Bowen last flew on Atlantis in May 2010 as part of the STS-132 crew. Flying on the STS-133 mission will make Bowen the first astronaut ever to fly on consecutive missions.
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Aug 29th 2005 8 miles east of NOLA
Video taken by Guerra Family after Hurricane Katrina. Chalmette, LA.


Listen to this Man who stayed when told to leave and consider your actions now, when the same order comes this year.


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Quoting aquak9:
I'm trying to remember some other specific benchmarks from the early and mid 80's, but I was young then and wouldn't have been paying much attention to everything that didn't directly concern me.

6-pak of Miller High Life for $1.99


25 cent pitchers at the rendezvous inn.
Member Since: Posts: Comments:
I'm trying to remember some other specific benchmarks from the early and mid 80's, but I was young then and wouldn't have been paying much attention to everything that didn't directly concern me.

6-pak of Miller High Life for $1.99
Member Since: August 13, 2005 Posts: 178 Comments: 26675
Fiji Meteorological Services
Tropical Cyclone Advisory #14
SEVERE TROPICAL CYCLONE ATU (11F)
18:00 PM FST February 21 2011
=======================================

At 6:00 AM UTC, Severe Tropical Cyclone Atu, Category Four (949 hPa) located at 18.3S 170.2E has 10 minute sustained winds of 90 knots. The cyclone was reported as moving southeast at 5 knots. Position good based on multispectral enhanced infrared radar/visible imagery with peripheral surface observations.

Hurricane Force Winds
======================
30 NM from the center

Storm Force Winds
===============
60 NM from the center in eastern semi-circle
40 NM elsewhere

Gale Force Winds
===============
200 NM from the center in northeast quadrant
160 NM from the center in southeast quadrant
120 NM from the center in southwest quadrant
100 NM from the center in northwest quadrant

Structure of the system has slightly weaken in last 6 hours, but the overall organization remains good in the past 24 hours. Eye has slightly exposed. Slight warming of cloud tops past 6 hours. Primary bands to south of system dissipated while the band to the north has consolidated and wrapped around low level circulation center. Outflow good to north and east but restricted elsewhere. Sea surface temperature is around 29C. System lies along in a weak shear environment. CIMSS indicates decreasing shear along forecast path. System is being steered southeast by a weak northwesterly deep layer mean wind.

Dvorak assessment based on eye patter with DG eye and LG surround yielding DT=5.0, MET=5.0, PT=5.0. Final Dvorak T number based on DT.

Dvorak Intensity: T5.0/5.5/D0.5/24 HRS

Global models moves the system southeastward and slightly intensifies it.

Forecast and Intensity
========================
12 HRS: 19.8S 170.7E - 95 knots (CAT 4)
24 HRS: 21.8S 171.4E - 95 knots (CAT 4)
48 HRS: 26.9S 174.5E - 60 knots (CAT 2)

The next tropical cyclone advisory from Fiji Meteorological Services will be issued at 14:30 PM UTC.
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Perth Tropical Cyclone Warning Center
Tropical Cyclone Advice #39
TROPICAL CYCLONE CARLOS (17U)
3:00 PM WST February 21 2011
===============================================

At 2:00 pm WST, Tropical Cyclone Carlos, Category One (990 hPa) located at 18.0S 120.4E, or 320 km northeast of Port Hedland and 195 km west of Broome has 10 minute sustained winds of 40 knots with gusts of 55 knots. The cyclone is reported as moving west southwest at 11 knots.

Gale Force Winds
===============
80 NM from the center in northwestern quadrant
70 NM from the center in southwestern quadrant
40 NM from the center in northeastern quadrant
40 NM from the center in southeastern quadrant

Dvorak Intensity: T3.0/3.0/D1.0/24 HRS

Tropical Cyclone Carlos is expected to continue moving in a general west southwest track roughly parallel to the Pilbara coast and gradually intensify overnight and on Tuesday.

GALES with wind gusts to 100 kilometres per hour may develop in coastal areas between Wallal and Port Hedland later this evening extending west to Karratha Tuesday morning and then towards Exmouth later on Tuesday. There is the risk of DESTRUCTIVE winds with gusts exceeding 125 kilometres per hour overnight between Port Hedland and Whim Creek, then extending further west during Tuesday. Gales may then extend south to Cape Cuvier on Wednesday.

Residents of Pilbara coastal towns are warned that tides may rise significantly above the high water mark as the cyclone moves down the coast, even if it doesn't cross the coast. DAMAGING WAVES and FLOODING of low lying coastal areas are possible particularly on Tuesday's high tide in the Karratha region.

HEAVY RAIN is expected to cause significant stream rises with possible localised flooding for Pilbara coastal streams later today and Tuesday. Refer to the Flood Advice for the Pilbara [IDW39620].

Tropical Cyclone Watches/Warnings
====================================

A Cyclone WARNING is current for coastal areas from Wallal to Exmouth, extending to the adjacent inland Pilbara including Millstream.

A Cyclone WATCH is current for areas from Exmouth to Cape Cuvier, extending to adjacent inland areas including Nanutarra and Minilya Roadhouse.

The Cyclone WARNING from Bidyadanga to Wallal has been cancelled.

Forecast and Intensity
====================
12 HRS: 19.1S 118.5E - 45 knots (CAT 1)
24 HRS: 20.3S 116.5E - 50 knots (CAT 2)
48 HRS: 22.5S 113.2E - 60 knots (CAT 2)
72 HRS: 24.9S 110.1E - 65 knots (CAT 3)

Additional Information
=======================

Tropical cyclone Carlos is moving on a west southwest track towards the Pilbara coast. Deep convection is evident northwest of the centre but the system is battling 20 knots of easterly wind shear. Dvorak estimates range from 2.5 [curved band wrap of 0.5] to 3.o [shear pattern <0.5 deg. from deep convection] with FT/CI=3.0. Maximum winds at 40 knots although AMSU estimates are higher [72 knots 1-min average].

The forecast track persists steadily to the west southwest taking it very close to the Pilbara coast under the influence of a middle-level ridge to the southeast. Model guidance indicates relatively high confidence in the consensus track due to low spread. A coastal crossing remains a possibility in the next 36 hours.

The current forecast indicates some intensification off the Pilbara coast. Despite high ocean heat content, moderate easterly shear should constrain intensification. Once clear of land in the longer term there is a better chance of intensification when shear eases..

Carlos presents a significant storm surge threat especially as tides are close to HAT in this region during the next few days. The shelf wave is likely to cause tides to rise above the high water mark regardless of whether the cyclone directly causes a storm surge on the coast.

The next tropical cyclone advice from Perth Tropical Cyclone Warning Center on Tropical Cyclone Carlos will be issued at 10:00 AM UTC..
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Perth Tropical Cyclone Warning Center
Tropical Cyclone Bulletin
TROPICAL CYCLONE DIANNE (16U)
3:00 PM WST February 21 2011
==========================================

At 2:00 pm WST, Tropical Cyclone Dianne, Category Two (980 hPa) located at 25.9S 103.3E, or 1050 km west of Carnarvon and 1160 km west northwest of Geraldton has 10 minute sustained winds of 50 knots with gusts of 70 knots. The cyclone is reported as moving southwest at 10 knots.

Dvorak Intensity: T3.0/4.0/W1.5/24 HRS

Storm Force Winds
==================
40 NM from the center

Gale Force Winds
=================
120 NM from the center in

Forecast and Intensity
======================
12 HRS: 27.5S 102.6E - 45 knots (CAT 1)
24 HRS: 29.8S 102.7E - 35 knots (CAT 1)
48 HRS: 33.0S 103.9E - 30 knots (TROPICAL LOW)
72 HRS: 38.6S 104.3E - 30 knots (TROPICAL LOW)

Additional Information
=======================

Position based on visible satellite imagery. An eye appears evident in visible imagery but EIR and microwave shows a lack of deep convection persisting near the centre. Ascat pass at 02Z showed wind observations of 40kts. Using a curved band pattern gives a 1.0 wrap. Shear pattern on the EIR image gives a DT=3.0. MET=3.5. Final T=3.0 based on DT. Current intensity was held at 4.0 with mean winds at 50 knots consistent with SATCON estimates.

Forecast track moves the system southwest then south over cooler SSTs, thus TC Dianne is expected to weaken reasonably quickly over the next 24 to 36 hours as ocean heat content reduces and increasing shear develops over the system.

The next tropical cyclone bulletin from Perth Tropical Cyclone Warning Center on Tropical Cyclone Dianne will be issued at 13:00 PM UTC..
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I'm bored of this off season gw debate/arguing it leads to grumpy people too often. I'm waiting for the cane season to begin and waves to emit off Africa! :)
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Scientists warn of $2,000bn solar ‘Katrina’

By Clive Cookson in Washington

Published: February 20 2011 17:50 | Last updated: February 20 2011 17:50

The sun is waking up from a long quiet spell. Last week it sent out the strongest flare for four years – and scientists are warning that earth should prepare for an intense electromagnetic storm that, in the worst case, could be a “global Katrina” costing the world economy $2,000bn.......
Member Since: October 1, 2007 Posts: 81 Comments: 26516
Goodnight everyone. The math in here is becoming too complex for me....

[Besides, gotta get out early tomorrow :o(....]
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Member Since: October 1, 2007 Posts: 81 Comments: 26516
Re: post #2, KOTG:

One of the reasons why anti-GW protests are so strong amongst the "drill, baby, drill" crowd is that there's no money in renewables for them. Energy costs would plummet if everyone switched to renewable energy sources. Basically BP and the other Big Energy companies would be out of business. So they are trying to milk the cash cow as much as possible before the udders dry up....
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