Medium Range Discussion Winter 2011-12

[csnavywx]

It's been persistently very warm this winter, that's for sure. With March looking to be well above normal, and April looking to be above normal, I'm going to be planting well ahead of schedule for just about everything this year.

[gardenguy]

Frivolousz21

In regard to suspect highs in the early years of record keeping, many Weather Bureau Offices where located in center cities and often in a downtown building with the instruments on the top of the building. As such they were surrounded by black roofs and did not have the exposure requirements that currently apply. Many big city records for high temperatures have occurred prior to the observations being moved to airport locations where most are now.

[JamieOber]

It's been persistently very warm this winter, that's for sure. With March looking to be well above normal, and April looking to be above normal, I'm going to be planting well ahead of schedule for just about everything this year.

Man, I'd still pay attention to last frost date rules. One frosty night in the middle of a +10 pattern, and it's goodbye frost-sensitive plants.

[CoastalWx]

The agreement for the overall torch is pretty remarkable.

[easternsnowman]

The agreement for the overall torch is pretty remarkable.

Which means it will probably fail.....lol!

[JamieOber]

Which means it will probably fail.....lol!

Torches haven't failed this winter.

[The_Global_Warmer]

That has to be out to lunch or we are talking widespread 70s, 80s and 90s in the south.

WIthout snow cover, many in the northern plains would have 70s and maybe 80s. Downsloping winds with 20C 850s rolling off the Rockies.

This is not just a Western/Central and southern Canada thing. This is almost Coast to Coast.

[The_Global_Warmer]

The North American Snow Pack would take a beating:

This would make this CONUS snow season epically failed.

Not that I think it will but if that ran verbatim it would wipe out just about all CONUS snow that wasn't in mountains.

So is there something there, or is this just model BS?

[donsutherland1]

Verification:

My February 2012 thoughts that were posted in Message #703 were as follows:

The composite map for February that I have come up with based on the above assumptions is:

Adjustments based on the observed decadal change in temperatures for February would be a somewhat warmer outcome than what is shown for New England and the eastern Great Lakes region and a somewhat cooler (but still mild outcome) for the Southeast. The Pacific Northwest would also be adjusted to somewhat milder but still have cooler than normal temperatures.

In sum, I believe February will likely wind up warmer than normal across much of North America, including southern Ontario and southern Quebec. The Pacific Northwest (Oregon, Washington, British Columbia) could have another cooler than normal month. Alaska/extreme western Canada also look to remain colder than normal, on average. In the warm areas, cold shots will generally be short-duration events. Some opportunities for snowfall might exist.

The February monthly anomalies were as follows:

[The_Global_Warmer]

The 00z GFS still has the torch. Which would crush the North American snow cover.

Euro:

Day 10 on the Euro:

The cold is bottle necked in Canada. What is more infuriating is that Barents Sea Anomaly continues and get's stronger again. A very powerful SLP is forming from Southern Greenland all the way up the East Coast. Looks like some kind of large phase. The Euro and GFS both bomb it out into the 960's on Sunday night-Tuesday. Then another powerful vort max gets sucked into the vortex and amplifies going North and the low transfers and drops from the 970s and 960s to the 945MB range on both the GFS and EURO. Then the SLP weakens and retrogrades more West after curling back NW. This continues to happen over and over.

Instead of traveling into Europe the SLPS either go full circle north into the Arctic and gets sucked back into the larger flow as they weaken quickly. Or they meander out into the North Central Atlantic and head into the Arctic right west of the Barents and sit somewhere in vicinity to the ice area and the warm ocean where those cyclones can pull heat and moisture off of 6-10C water temps, which are running 1-2C above normal. But are showing signs of being tapped out. But the models lock the cold in Eastern Asia/Siberia all the way down to the SOO which is likely going to continue to grow ice and likely stay cold as well as the Bering area. Both seem to help feedback the constant cold with so much snow and ice in the region.

Also the Baffin Bay/Hudson Bay area's will continue to get very cold 850s once again.

So why does the cold get locked up?

[donsutherland1]

Verification:

My February 23-29, 2012 thoughts (Message #1106) were as follows:

The composite temperature anomalies based on ENSO Region 3.4 anomalies of -1.55°C to -0.70°C, an AO of 0.00 to +1.50, and a PNA of -1.00 to 0.00 for the 2/20-29/1950-2011 timeframe for North America and Europe are below:

With the CPC site not updating the spread of the GFS ensemble members for the teleconnections, there is greater uncertainty than usual. For North America, a larger portion of the Pacific Northwest could wind up cooler than shown on the composite (normal areas could wind up cool). For Europe, some of the area shown as near normal in Western Europe might be somewhat below normal. The general ideas of warmth across much of the eastern CONUS and cold in Europe, with the cold in Europe centered farther east, appear reasonable.

The anomalies for the timeframe in question were as follows:

The higher AO likely contributed to more widespread warmth in Europe. The brief period of PNA+ may have contributed to the colder anomalies across a large part of Canada.

[beavis1729]

Frivolousz21

In regard to suspect highs in the early years of record keeping, many Weather Bureau Offices where located in center cities and often in a downtown building with the instruments on the top of the building. As such they were surrounded by black roofs and did not have the exposure requirements that currently apply. Many big city records for high temperatures have occurred prior to the observations being moved to airport locations where most are now.

Agree...Chicago is a classic case of this:

PUBLIC INFORMATION STATEMENT

NATIONAL WEATHER SERVICE CHICAGO IL

630 AM CST MON MAR 5 2012 /730 AM EST MON MAR 5 2012/

...TOP TEN WARMEST WINTER ACROSS THE LOCAL AREA AND MUCH OF THE

REGION...

METEOROLOGICAL WINTER OFFICIALLY CONCLUDED AT THE END OF FEBRUARY

AND COMPRISES THE THREE MONTH STRETCH FROM DECEMBER 1ST THROUGH

FEBRUARY 29TH. WHILE SNOW AND COLD SNAPS ARE STILL POSSIBLE

DURING MARCH AND APRIL...THIS THREE MONTH STRETCH IS MOST OFTEN

REFLECTIVE OF WINTER WEATHER...AND IS MOST REGULARLY USED BY

METEOROLOGISTS AND CLIMATOLOGISTS TO COMPARE SEASONAL DATA.

CHICAGO...

THE WINTER HAD AN AVERAGE TEMPERATURE OF 32.8 DEGREES...WHICH WAS

6.4 DEGREES ABOVE NORMAL. THIS TIES THE WINTER FOR THE 9TH WARMEST

IN THE PAST 140 YEARS (SINCE 1872)...AND WAS THE SECOND WARMEST

WINTER IN THE PAST 80 YEARS. THIS WAS THE WARMEST WINTER SINCE

1997-1998.

RANK WINTER AVERAGE WINTER TEMP

---------------------------------------

1. 1877-1878 37.2

2. 1931-1932 35.7

3. 1879-1880 35.2

1881-1882 35.2

5. 1889-1890 34.7

6. 1875-1876 33.6

7. 1997-1998 33.2

8. 1918-1919 33.1

9. 2011-2012 32.8

1920-1921 32.8

[Snowstorms]

According to the ONI, 2011-12 was an official La Nina as on the MEI scale.

It peaked at -1.0 on the ONI with the latest value for DJF at -0.9. And it seems as though last year was a Strong La Nina on the ONI scale.

http://www.cpc.ncep....ensoyears.shtml

They've now converted to a new base line. MEI hasnt updated yet.

Lets see where the ENSO heads thru this Spring and Summer. Would be interesting if next year was another Nina, lol.

[Amped]

The potential in this setup has a wide range of solutions. It could manifest as ugly as 1956 or it could manifest like late March of 1953. All of the years, at some point, developed a sharp low anomaly across the Mid Atlantic / Southeast etc. during the second half of March. I have absolutely no idea which way this will go down yet.

Haven't forgotten. I will gladly admit I was worng if this verifies.

[The_Global_Warmer]

Agree...Chicago is a classic case of this:

PUBLIC INFORMATION STATEMENT

NATIONAL WEATHER SERVICE CHICAGO IL

630 AM CST MON MAR 5 2012 /730 AM EST MON MAR 5 2012/

...TOP TEN WARMEST WINTER ACROSS THE LOCAL AREA AND MUCH OF THE

REGION...

METEOROLOGICAL WINTER OFFICIALLY CONCLUDED AT THE END OF FEBRUARY

AND COMPRISES THE THREE MONTH STRETCH FROM DECEMBER 1ST THROUGH

FEBRUARY 29TH. WHILE SNOW AND COLD SNAPS ARE STILL POSSIBLE

DURING MARCH AND APRIL...THIS THREE MONTH STRETCH IS MOST OFTEN

REFLECTIVE OF WINTER WEATHER...AND IS MOST REGULARLY USED BY

METEOROLOGISTS AND CLIMATOLOGISTS TO COMPARE SEASONAL DATA.

CHICAGO...

THE WINTER HAD AN AVERAGE TEMPERATURE OF 32.8 DEGREES...WHICH WAS

6.4 DEGREES ABOVE NORMAL. THIS TIES THE WINTER FOR THE 9TH WARMEST

IN THE PAST 140 YEARS (SINCE 1872)...AND WAS THE SECOND WARMEST

WINTER IN THE PAST 80 YEARS. THIS WAS THE WARMEST WINTER SINCE

1997-1998.

RANK WINTER AVERAGE WINTER TEMP

---------------------------------------

1. 1877-1878 37.2

2. 1931-1932 35.7

3. 1879-1880 35.2

1881-1882 35.2

5. 1889-1890 34.7

6. 1875-1876 33.6

7. 1997-1998 33.2

8. 1918-1919 33.1

9. 2011-2012 32.8

1920-1921 32.8

It is highly improbable that the 1870s and 1880s had such extremes over the conus. Some of St. Louis warmest winter months are the 1870s like December averaged 49.8F for the month. That is 18F above the long term mean. That is next to impossible. The local bloggers believe it. But I don't.

The required pattern during the yearly solar low would be historic with a giant slp sitting over the PNW-Idaho and a huge HP sitting East of here with a constant flow Allowing incredible daily anomalies.

In other words it didn't happen.

[wxmx]

It is highly improbable that the 1870s and 1880s had such extremes over the conus. Some of St. Louis warmest winter months are the 1870s like December averaged 49.8F for the month. That is 18F above the long term mean. That is next to impossible. The local bloggers believe it. But I don't.

The required pattern during the yearly solar low would be historic with a giant slp sitting over the PNW-Idaho and a huge HP sitting East of here with a constant flow Allowing incredible daily anomalies.

In other words it didn't happen.

It could happen...a very -PNA setup. You can cross check the anomalies for Seattle, for example

[Harry]

It is highly improbable that the 1870s and 1880s had such extremes over the conus. Some of St. Louis warmest winter months are the 1870s like December averaged 49.8F for the month. That is 18F above the long term mean. That is next to impossible. The local bloggers believe it. But I don't.

The required pattern during the yearly solar low would be historic with a giant slp sitting over the PNW-Idaho and a huge HP sitting East of here with a constant flow Allowing incredible daily anomalies.

In other words it didn't happen.

Look at Lansing's climo data. Same thing happened there and that station/area has NOT changed unlike many others like Chicago etc. Surely they all cant be wrong.

It could happen...a very -PNA setup. You can cross check the anomalies for Seattle, for example

I am near certain it did happen. A number of stations that has data back to the 1860s/70s shows the same especially in this region.

[The_Global_Warmer]

I am not saying that wasn't a warm period where records were set. But there is a difference in St. Louis reaching 43 or 44F and setting a record, than only in that period having crazy anomalies that are off the charts. And make you wonder how it was physically possible.

There had to be zero cold air on this side of the N.H. with horrible snow cover into Canada. Because any cold fronts in December will bring even marginal chilly air with highs in the 40s and lows in the 20s.

December 2012 finished with 50F or more for the high 14 times. Which is a lot.

It was 47F or above 21 times which is a whole lot.

19F was the coldest temp which is nothing. This year averages 48.7F for the high and 32.8F for the low. December of 2012 was 6.3F above the 1981-2010 climo and over 7F above the long term climo. This was the beginning of the 6th warmest winter on record in STL. The top 5 were 81 years ago and the rest in the 1800s. The 7th warmest is also from the 1800s.

So the year that was almost at 50F average temperature for the entire month of December The high would have to be around 59F everyday with a low around 40.5F

Could be a closer margin or further away.

But with the December sun. I can't even picture in my head a pattern that would sit so stable to bring us warm enough mid level temps and sunshine to make it work. That seems impossible to me considering the sun. I guess I should not say impossible. But it is something I will be skeptical of when it deviates that much from the normal.

[donsutherland1]

Some morning thoughts...

1. With the AO remaining positive, the current cold shot will again prove fleeting in eastern North America.

2. For the medium-term, the AO is likely to remain predominantly positive and the PNA will likely remain neutral to negative. Moreover, the EPO is likely to grow even more strongly positive prior to mid-month.

3. The MJO is currently approaching Phase 4. The ensemble guidance suggests that it could be in Phase 5 or Phase 6 after mid-month, possibly with a decelerating rate of progressions.

As a result, the stage could be set for near coast-to-coast warmth for the CONUS, as well as a large area of warmth in Canada following mid-month. Teleconnections analogs suggest less warmth in Canada.

[donsutherland1]

Verification:

From Message #808:

As for February, it is probably more likely than not that Toronto won't have any days on which the temperature falls to -20°C or below. Such days in February have not been very common since 2000. The pattern that I expect in February would probably lower the probability of such days.

Toronto's coldest temperature during February was -13.9°C (7.0°F) on February 11, 2012.

[donsutherland1]

March 16-23, 2012 Thoughts:

Despite the recent cold shot that impacted portions of North America, the first half of March remains on course to be warmer than normal in much of North America, except for Canada, parts of the West, and Alaska. During the March 16-23, 2012 timeframe, it appears that the area of warm anomalies could expand to include a large part of Canada, as well.

Below are the the probability of cold, normal, warm anomalies for the March 14-20 timeframe on the NAEFS and those from the forecast teleconnections. The teleconnection anomalies assume ENSO Region 3.4 anomalies in the -0.9°C to -0.2°C range, an AO in the 0.00 to +2.00 range, and PNA in the -0.50 to +0.50 range. The ECMWF ensembles favor a negative PNA, while the GFS ensembles favor a positive PNA.

Using the NAEFS and taking into consideration the observed decadal temperature trends, I would adjust the teleconnection analogs so that my thinking would be as follows:

- Warm across much of Canada, except for Northwest Canada and perhaps northern Canada where cold anomalies would likely prevail.

- Warm across much of the CONUS except for the West Coast and perhaps western quarter of the country where cold anomalies could prevail. The East Coast would remain warmer than normal.

- Alaska would generally be colder than normal.

Any cold shots in the central and eastern U.S. would likely be modest and short-lived.

[The_Global_Warmer]

That would create some highly anomalous temperature records in places.

[WxUSAF]

That would create some highly anomalous temperature records in places.

Aren't records "highly anomalous" by definition?

[DaculaWeather]

something anomalous : something different, abnormal, peculiar, or not easily classified

So there could be different "levels".

[WxUSAF]

Right...and an event that's never happened before (a record) is "highly" anomalous.

Enough semantics.

[bluewave]

It is highly improbable that the 1870s and 1880s had such extremes over the conus. Some of St. Louis warmest winter months are the 1870s like December averaged 49.8F for the month. That is 18F above the long term mean. That is next to impossible. The local bloggers believe it. But I don't.

The required pattern during the yearly solar low would be historic with a giant slp sitting over the PNW-Idaho and a huge HP sitting East of here with a constant flow Allowing incredible daily anomalies.

In other words it didn't happen.

Check out the teleconnection pattern. 1877-1878 was the strongest El Nino on record for the 19th century.

[donsutherland1]

Verification:

With respect to the March 1-7, 2012 timeframe, I noted in #1183 in this thread:

Given the forecast teleconnections, progression of the MJO, and continuing La Niña conditions, I suspect that there will be two big meteorological stories during the opening week in March:

1. Much of Canada turns cold.

2. Colder than normal temperatures hold on across a large part of Eastern Europe into Russia.

I also provided the following chart:

Top Left: The composite temperature anomalies for ENSO Region 3.4 anomalies of -1.35°C to -0.60°C, a PNA of -1.25 to -0.50, and an AO of +1 to +2 for North America.

Top Right: The composite temperature anomalies for Europe using the same ENSO-Teleconnections listed above.

Bottom Left: March temperature anomalies for La Niña conditions when the MJO was in Phase 3 or Phase 4.

Bottom Right: The observed decadal temperature change for March.

Afterward, I stated:

I believe both composite charts offer a good idea of what to expect during the first week in March. The corrections I would make based on the observed decadal change would be to expand the warm anomalies across the northern portion of the British Isles into perhaps western Norway. Also, the cold would probably not be as severe as shown on the composite in Eastern Europe.

The actual outcomes were as follows:

The major difference between the forecast and actual outcome is that a much larger portion of northern Europe was warmer than normal. The adjustment that extended warmth into western Norway fell short of what actually transpired.

[donsutherland1]

A few quick morning thoughts...

1. Next week and the week after could see excessive warmth in large parts of eastern North America, including eastern Canada. On the few days where there is precipitation, the warmth could be dented but readings will very likely remain above normal.

2. The cold that has been progressing, in the means, northward across Canada will continue to do so.

3. For April, there is an interesting intersection between generally warm analogs currently showing up and the aggressive observed warming that has occurred during the past decade in the James Bay/southern Hudson Bay region of Canada.

[wxmx]

Euro @day 10 is a caricature of how this winter transpired...exaggerated features and brings you a smile because of how ludicrous it looks. That's a nice omega block. >25C in parts of Ontario and Quebec?

[SN_Lover]

Late Winter??

MJO also projecting calm conditions in the near to medium term.