• Quotes/Images/News Articles From Last Winter

• How Cold Was Last Winter

• ENSO, Large Scale Patterns (PNA/NAO/AO)

• Mean Upper Air Composites From Past Winters

• What Indices Can Be Used & Possibly Predict Warmer or Colder Winters

*Winter 2013-14

*Quotes/Images/HumorTwitter/Facebook/News Articles

December 2013Backyard Rink Done. Bring on the

Cold Weather!

Might Cry Tears of Joy if There's a Snow Day Tomorrow.

Snow on ground... Fire in the fireplace… Good hoops on TV… Thank

you, Santa, for the Early Gift.

January 2014

February 2014

My car handles this Snow about as well as the Titanic handled the

Atlantic Ocean

Best part of the cold!!! predicted a high of 4 on Thursday. On the bright

side haven't seen a mosquito in months!

Global Warming Lecture Cancelled Due to Unexpected Blizzard

March 2014

1 1874-1875 4.0 2 1886-1887 5.7 3 1935-1936 7.3 4 1872-1873 7.9 5 1903-1904 8.4 6 1916-1917 8.5 7 1882-1883 9.2 8 1978-1979 9.4 9 2013-2014 9.7 (Yes! It was a Cold Winter)

*How Cold Was It?Coldest Winters in the Twin Cities: 1872-73 to 2013-14

1981-2010 Normal: 18.7 degrees F (Using Data From xmACIS2. Seasonal Calculations Method – Average of High/Low Temperature by Days

(December 1st thru February 28th)

*What is considered NormalDue to simplicity, this presentation will use the Minneapolis/St. Paul International Airport for records, normals and winter trends (Using the typical December 1st to February 28th for Climatology).

Record Highs

Record Lows

Winter 2013-

14

32°

0°

*How Cold Was It?Average Mean Temperature

Winter Months

Coldest In The Last 33 Years

Average Mean

Temperature9.7 F

Coldest On Record

4.0 F (1874-75)

Average Mean Temperature In Winter

Winter of 2013-14°

Last Colder Mean Temperature

Winter of 1978-79 (9.4F)

*How Cold Was it?

There Were 9 Days In The

Past 33 Years That Were Colder Than -23 F

What About Extremes… Lowest Temperatures That Had Record Lows?

A Reflection of Longevity Vs. Short-Term Cold Spells

-29F (1983-84), Only Ranked 43rd Coldest Winter

-32F (1995-96), Only Ranked 60th Coldest

Winter

Lack Of Extreme Lows In The 2000s

*How Cold Was it? Consider How Many Days Were Below

+10F, 5F, 0F, -10F, -15, -20F, -25F During the Last 33 Years? All Recorded Years?

Do You See Any Trends?

*How Cold Was it? The Top Coldest

Winters Vs. Coldest

Temperatures On Record

Coldest Winters Coldest Temp For That Winter

1 1874-1875 4.0 -32

2 1886-1887 5.7 -363 1935-1936 7.3 -344 1872-1873 7.9 -315 1903-1904 8.4 -336 1916-1917 8.5 -257 1882-1883 9.2 -318 1978-1979 9.4 -28

9 2013-2014 9.7 -23

1887-88 -411879-80 -39*1886-87 -361885-85 -361969-70 -341935-36 -34*1885-86 -34*1903-04 -331898-99 -33

Top Coldest Lows:

Having extreme low temperatures doesn’t necessarily mean a Very Cold Winter And Vice Versa

*El Niño-Southern Oscillation (ENSO)

Fluctuating Ocean Temperatures along the Equatorial Pacific

- Naturally Occurring Phenomena - Warm Phase, Cold Phase, Neutral Phase

Effects on the Upper Midwest

- During El Niño Years… - There is a Higher Probability of a Warmer Winter

- During La Nina Years…- There is a Higher Probability of a Colder Winter

- During Neutral Years…- No Significant Probability Either Way.

*Top Coldest Winters Since

19811 2013-2014 9.7 Neutral2 1981-1982 11.7 Neutral3 2000-2001 13.2 La Nina- 1993-1994 13.2 Neutral5 1985-1986 13.5 Neutral6 2008-2009 14.0 La Nina7 1983-1984 14.1 La Nina8 1996-1997 14.4 Neutral9 1984-1985 14.8 La Nina10 2007-2008 15.0 La Nina

*Top Warmest Winters Since

19811 2001-2002 26.8 Neutral2 2011-2012 26.2 La Nina3 1997-1998 25.8 El Nino4 1986-1987 25.7 El Nino5 1982-1983 23.9 El Nino6 1991-1992 23.6 El Nino7 1999-2000 23.0 La Nina8 2005-2006 22.8 La Nina9 2004-2005 21.4 El Nino- 1998-1999 21.4 La Nina

* Conditional Height Anomalies During Positive & Negative Phases of The PNA/NAO/AO

Pacific/North American – North American Oscillation – Arctic Oscillation

Characteristics of +NAO/-NAOStronger Jet Stream

Stronger Icelandic LowStronger Azores Highs

Warmer Eastern U.SLess Build Up Cold Air

Weaker Jet StreamColder Air Builds Up/Spills South

Colder Eastern U.S.

Characteristics of +PNA/-PNAStronger 50H Western U.S.

Colder Air Spills Southward Northern Plains/Eastern U.S.

Colder/Drier

Stronger Trough Western U.S.Southwestern Flow

Warmer/Wetter Northern Plains

Characteristics of +AO/-AOCold Air Stays North

Stronger/Less Wavy Jet Stronger Trade Winds

Below Average 50H in Arctic

Colder Air Spills South Weaker/More Wavy JetWeaker Trade Winds

Above Average 50H in Arctic

Positive/Negative Phases of the PNA/NAO/AO Have Larger Effects on Short Term Weather Extremes

*Typical Cold Upper Midwest Teleconnections

PatternNegative AO

Positive PNA

Polar VortexDrops South

As A Result of -AO

Positive NAO

* Composite Anomaly 500 mbCold Winters

Average vs 2014

* Composite Anomaly 500 mbWarm Winters

Average vs 2012

*What Indices Could be Used For Forecasting

Winter Trends

Long Term (3 – 6 Months)

• El Nino Vs. La Nina Vs. Neutral

http://www.eas.slu.edu/CIPS/ANALOG/extended.phphttp://hopwrf.info/CFS/

http://www.cpc.ncep.noaa.gov/products/CFSv2/CFSv2seasonal.shtml

Short Term (1 – 3 Weeks)• PNA… NAO and AO

Phases

http://ssd.wrh.noaa.gov/satable/#

Final Thoughts The Winter of 2013-14 Was…

• More Cumulative of Cold Temperatures Vs Extremes

A Common Theme For The Coldest Winters in the Past…• Greater # Of Days Where Overnight Low Temperatures Were Below Zero

The Correlation of the Positive & Negative Phases of the PNA, NAO & AO Have Much Larger Impacts On Winter Patterns/Trends In The Upper Midwest In The Short Term (1 - 3 Weeks Out)

For the Upper Midwest to Have A Similar “Cold” Winter of 2013-14• +PNA, -AO, +NAO Combination (At Least Short Term)

*Other Interesting Discussions…References…

Scientific Discussions on Climate Change…- More Extreme Weather Events Are Coming Years

Due To Climate Change- The Effects of Less Sea Ice in the Arctic is Causing More Severe

Winters in the Northern Plains. - The Expansion of Antarctica Sea Ice… How Does This Play

In The Climate Change Model

http://www.ncdc.noaa.gov/

http://www.climate.gov/

http://www.globalchange.gov/