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2014 Northern Hemisphere Snow Cover Thread


The_Global_Warmer

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Most of that difference is not snow cover, its a weak surface low tracking neat the ND/SD border. MN is snow covered and near 50 up near the Canadian border.

 

 

Look's like the snow cover is not equal throughout.

 

 

 

NAM_221_2013032918_F03_SNOWIN_SURFACE.pn

 

 

NAM_221_2013032918_F03_TMPF_2_M_ABOVE_GR

 

 

once again tomorrow with "no hardly impacting" weak SLP to cause "most" of the temperature difference there is widespread NW winds with CAA.

 

The same gradient shows up from Minnesota/Wisconsin back to Montana.  Like right now even with NW winds coming off the remaining snow field temps are progged to jump 20-25F in spots where snow is and isn't.

.

NAM_221_2013032918_F27_TMPF_2_M_ABOVE_GR

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Look's like the snow cover is not equal throughout.

 

 

 

NAM_221_2013032918_F03_SNOWIN_SURFACE.pn

 

 

 

 

 

once again tomorrow with "no hardly impacting" weak SLP to cause "most" of the temperature difference there is widespread NW winds with CAA.

 

The same gradient shows up from Minnesota/Wisconsin back to Montana.  Like right now even with NW winds coming off the remaining snow field temps are progged to jump 20-25F in spots where snow is and isn't.

.

 

 

 

Those NAM snow depth maps are horrible. Most of the northern half of MN is under over 15 inches of snow...and temps are around 50F right now. And just to the west also under snow cover the temps are in the lower 30s...this is because they have weak cold air damming from the sfc low.

 

 

1_day_snowdepth_21.gif

 

 

Mar29_plains_Snow.png

 

 

 

 

 

20F temp differences do not happen from snow cover alone. The difference is typically around 8-12F under optimal conditions all else being equal. When there is strong mixing in the atmosphere, the difference is much less.

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Look's like the snow cover is not equal throughout.

once again tomorrow with "no hardly impacting" weak SLP to cause "most" of the temperature difference there is widespread NW winds with CAA.

The same gradient shows up from Minnesota/Wisconsin back to Montana. Like right now even with NW winds coming off the remaining snow field temps are progged to jump 20-25F in spots where snow is and isn't.

.

Those NAM snow depth maps are horrible. Most of the northern half of MN is under over 15 inches of snow...and temps are around 50F right now. And just to the west also under snow cover the temps are in the lower 30s...this is because they have weak cold air damming from the sfc low.

20F temp differences do not happen from snow cover alone. The difference is typically around 8-12F under optimal conditions all else being equal. When there is strong mixing in the atmosphere, the difference is much less.

Southern wind brings warmth and.... Wind. Wind really kills the snowpack effect on temps... Double whammy in Minnesota.

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  • 2 weeks later...

2013088.png

 

 

Big warm up coming to Southern Russia even into SWC Russia and Eastern Europe.

 

Cold in the CONUS until day 6-7 before +AO comes and torching starts.

 

 

The torching was limited in scope and short-lived. Much colder weather has spread across much of the nation again, and we have another big shot of much below normal weather coming up next week. That's been the story in 2013 since mid-January.

 

And the NH snowcover situation heading into mid-April is considerably better than last year.

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The torching was limited in scope and short-lived. Much colder weather has spread across much of the nation again, and we have another big shot of much below normal weather coming up next week. That's been the story in 2013 since mid-January.

 

And the NH snowcover situation heading into mid-April is considerably better than last year.

 

 

April has a shot to finish above normal for snow cover for the first time since 2003...we're going to have some decent positive departures at least through about the 20th I think (North American snow cover is going to be way above avg in this time)...beyond that is the question mark. Whether enough meltoff can happen in the final 10 days to offset the first 3 weeks of the month.

 

 2013101.png

If April does in fact have a respectable showing in snow cover, it will be interesting to see if that has any affect later on for the sea ice or perhaps May/June snow cover.

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April has a shot to finish above normal for snow cover for the first time since 2003...we're going to have some decent positive departures at least through about the 20th I think (North American snow cover is going to be way above avg in this time)...beyond that is the question mark. Whether enough meltoff can happen in the final 10 days to offset the first 3 weeks of the month.

 

 2013101.png

If April does in fact have a respectable showing in snow cover, it will be interesting to see if that has any affect later on for the sea ice or perhaps May/June snow cover.

 

Could you or someone else tell me when the last time was that April had this much snow cover for North America on this date? Going back to 1997 i could not find any on this site. http://www.natice.noaa.gov/ims/

 

Thanks.

 

cursnow.gif

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It's looking like April is going to shatter the snow cover anomaly record.

 

The Russian side is starting to get really warm, well into the snow cover over eastern Siberia, you will see that below.  So larger area's of red will open up.  The Snow over SW Canada is about to be wiped out and most of the snow over the Eastern side of the Hudson Bay.  The models continue to trend very warm with downsloping heat into Canada.

 

 

 

2013120.png

 

 

At 06Z today you can see the warmth between the HP over the Arctic Pacific and the SLPs over the Kara region.  Temps jumped big time today. 

 

Visible Satellite shows large area's where the snow is nearly completely gone but Rutgers as of Yesterday had the snow line way South into the mass of 12-18C high temps.  The models still think there is more snow there than there really is and it's messing up guidance a bit.  We can also clearly see the deepest cold is over the NA side.  Big torching is about to come to Western and Eastern Canada but still make it's way into parts of Central Canada. 

 

 

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?mosaic=Arctic.2013121.terra.4km

 

 

 

siberiatorch_zpsa5847c41.gif

 

 

it's amazing we are going to have a record snow cover April and I believe within 5-7 days we will see snow cover fall deeply into negative anomaly territory.  Models essentially say the Canadian Archipelago down around the Western Hudson will keep snow for now and North Central Russia but Eastern Russia and the Western half of the snow pack will continue to melt out. 

 

 

I am going on a limb and predicting May get's a -4 mil km2 anomaly after Aprils 4-5 mil km2+ anomaly.

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It's looking like April is going to shatter the snow cover anomaly record.

 

The Russian side is starting to get really warm, well into the snow cover over eastern Siberia, you will see that below.  So larger area's of red will open up.  The Snow over SW Canada is about to be wiped out and most of the snow over the Eastern side of the Hudson Bay.  The models continue to trend very warm with downsloping heat into Canada.

 

 

 

2013120.png

 

 

At 06Z today you can see the warmth between the HP over the Arctic Pacific and the SLPs over the Kara region.  Temps jumped big time today. 

 

Visible Satellite shows large area's where the snow is nearly completely gone but Rutgers as of Yesterday had the snow line way South into the mass of 12-18C high temps.  The models still think there is more snow there than there really is and it's messing up guidance a bit.  We can also clearly see the deepest cold is over the NA side.  Big torching is about to come to Western and Eastern Canada but still make it's way into parts of Central Canada. 

 

 

http://lance-modis.eosdis.nasa.gov/imagery/subsets/?mosaic=Arctic.2013121.terra.4km

 

 

 

 

 

 

it's amazing we are going to have a record snow cover April and I believe within 5-7 days we will see snow cover fall deeply into negative anomaly territory.  Models essentially say the Canadian Archipelago down around the Western Hudson will keep snow for now and North Central Russia but Eastern Russia and the Western half of the snow pack will continue to melt out. 

 

 

I am going on a limb and predicting May get's a -4 mil km2 anomaly after Aprils 4-5 mil km2+ anomaly.

 

Don't see any reason to predict this. You have to account for the fact that this is the time of year where snowcover is typically lost quickly. In addition, looking at models especially the ECMWF, I think you are overestimating how fast snow will melt in Canada - there is no big torch coming.

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Don't see any reason to predict this. You have to account for the fact that this is the time of year where snowcover is typically lost quickly. In addition, looking at models especially the ECMWF, I think you are overestimating how fast snow will melt in Canada - there is no big torch coming.

 

 

As soon as the snow cover surplus is gone on the NA side.  There will be a large negative anomaly on the Russian side.

 

The Russian side outside of the blue dots in Eastern Russia is now quickly going negative and the weather calls for rapid melting to continue.

 

The models also call for a huge ridge to develop on the West Coast and pump very warm air into Canada, which will quickly melt out most of the deficit.  There is also going to be big melting in Eastern Canada.

 

2013121.png

 

 

May 1st Climo and to the right is May 7th climo.  There will be huge negative departures in the Eastern Siberian region.

 

121.png128.png

 

Warm air is already making it's way into Canada.  Models show the snow pack being eradicated quickly.  It's May 1st.  Unless it's cloudy and -5 to -10C 850s anything under 60N is going to melt pretty quickly with some warm air advection.

 

I don't feel like posting all of the temp maps but here is the GFS snow cover map for NA today vs day 5. 

 

By day 4 and 5 the GFS has most of the surplus if not all of it completely gone in NA.

 

Phztq3E.pngWOpQ5vm.png

 

 

Max warming in East Central Siberia

 

5mFqCyA.gif

 

 

 

 

 

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It's really warm over Eastern and NE Russia.  The GFS crap the bed so far on temps.  We can see at 06Z  The GFS had a small area of 10C temps over Eastern Russia surrounded by sub 10C temps because that area lost snow cover faster. 

 

Z1wOUJC.gif

In reality the area of 10C temps or so or higher is far larger.  And where the GFS had 10C there is 15-20C temps. We should continue to see temps very warm the next 5 days in this region. 

 

 

 

 

RLoL0Fe.gif

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The 0z Euro showed below normal temps returning to central Canada days 6-10.

 

 

attachicon.gif00zECMWF6-10day850mbTempAnomalyNA.gif

 

 

You are right.  This warm up is going to build in quickly and move out quickly.  But it appears to be rather potent.

 

At 18Z we can see the warmth continue to increase and build North into Canada. 

 

 

 

 

zOStj13.gif

 

 

The NAM shows

 

aBsfvw4.png

 

It also thinks by the end of the 84 hour period from 18z today most of the snow South of Central Canada will be gone...that seems a bit aggressive to me.  But there is going to be a very deep downsloping W to WSW to SW flow that has a very warm mid level air fetch as well.

 

YlGjipL.png

 

EDIT: 00Z NAM IS OUT:

 

CRwoFy2.png

 

 

 

 

The NAM 925mb temps at 1AM at the end of the run show why it thinks the snow is going to vanish in just a matter of days.

 

V6FLSdb.png

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The finals for April are not out yet.  I would expect a new record.

 

 But it appears the inevitable end of the big snow cover is coming and rapidly switching over to the typical huge negative departures.

 

The blue regions on the NA side will be either all the way gone or close within the next 3 days.  And the snow over the Eastern side of the Hudson is expected to retreat fairly far North as well.  If that happens it will become an area of negative departures. 

 

A cold front is expected to push South and slow down any further rapid melting to the North for now.  West of the Hudson.

 

 

Co3Kb1g.png

 

Like clockwork after what has been dubbed a harsh and cold winter in Asia. The snow cover is "melting".  Just melting rapidl.

 

 

 

MQpQjDr.jpg?1

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