2013-2014 Winter Forecast

Winter is almost here again. The Christmas Creep is getting earlier and earlier each year at retail stores as the Christmas season is shorter as Thanksgiving is on November 28, 2013. Some predict this winter will be cooler than normal. The last two winters were warm, 2011-2012 being the third warmest on record. Last winter was the 19th warmest on record. Since, there have been two warm winters, does this mean, we could have a cooler than normal winter?

Looking at data from the past, when there have been two warm winters, the following winter is cooler. For example 1998-1999 and 1999-2000 winter were warm, while 2000-2001 was cool. The winter of 1998-1999 and 1999-2000 are the top warmest winters on record. The winter of 2000-2001 is the 27th coolest winter on record. This is based on data going back to 1895.

What do I look at to predict what this coming winter will be like? I look at El Nino Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and Atlantic Multidecadal Oscillation (AMO). PDO and AMO last for years, while ENSO lasts for months. I usually tend to look at ENSO as a strong factor in winter forecasts. Many El Nino forecast have a Neutral phase for this winter. In this case, a cool Neutral, which is below the threshold of La Nina, which is -0.5° C. Last winter was a Neutral in the cool zone. So, I am going to pick analogs in which the following winter is Neutral, like the previous winter. Here are the analogs if I just look at El Nino.

1927-1928
1932-1933
1935-1936
1946-1947
1948-1949
1952-1953
1960-1961
1964-1965
1981-1982

Here is what those winters looked like in terms of temperature and precipitation. I used 20th Century Reanalysis Monthly Composites to generate the map.

2013-2014WinterAnalogTemperaturePrecipitationFall2013

In terms of temperature, Northern Canada, Alaska, Eastern Siberia, Korean Peninsula, Japan, and Northern Europe are cold. This also includes the Western and Upper Midwest of America. Texas and the South is warm. However, there have been Arctic blasts that have affected Texas and America in almost all the analog winters. Some winters saw more than one Arctic blasts. Some analog winters had no Arctic blasts at all, like 1952-1953, 1960-1961, and 1964-1965.

12/31/1927 to 1/5/1928
12/15/1932 to 12/19/1932
2/7/1933 to 2/12/1933
1/18/1936 to 1/20/1936
1/27/1936 to 1/31/1936
2/17/1936 to 2/19/1936
12/29/1946 to 1/5/1947
1/28/1949 to 2/1/1949
1/9/1982 to 1/17/1982

These were hard freezes in particular 1932, 1933, 1949, and 1982 for America, Texas, and Southeast Texas. The winter of 1935-1936 is one of the coldest winters on record for America, which was during the Dust Bowl. Now, let’s look at the precipitation rate.

In terms of rainfall, South and West are drier, while Pacific Northwest is wetter. Southern China and Central Europe are dry, while North Africa is wet. However, there have been flooding in those analog years in Texas. Here are the analog years that had flooding.

12/6/1935 to 12/8/1935-Massive flooding in Houston area from up to 20 inches of rain.
2/18/1982 to 2/21/1982-Heavy rain in Deep South Texas of over 7 inches of rain.
2/24/1982 to 2/26/1982-South Texas gets heavy rain centered around Corpus Christi area of over 6 inches of rain.

Here is a map of rainfall and temperature average and anomaly in the analog winters for Lower 48. It is generated from <a href=http://www.esrl.noaa.gov/psd/data/usclimdivs/US Climate Division Dataset Mapping Page.

2013-2014WinterAnalogsClimateFall01

The map shows normal rainfall for most of America. The dry areas are in California, Arkansas, and Missouri. The wet areas are Southeast and Pacific Northwest. In terms of temperature, most of America is cooler than normal, especially Western and Upper Midwest. Just looking at the map, this suggests that America could be in for a cool winter. The data is all based on 1981 to 2010 average temperature and rainfall. Now, let’s look at the average and standard deviation for America based on anomaly of 1895 to 2013. The data is from Division Data Select.

America Winter Analog
Temperature
Mean: 31.85°F
Median: 31.80°F
Lowest: 28.05°F (1936)
Highest: 35.54°F (1953)

Precipitation
Mean: 6.58
Median: 6.82
Lowest: 5.14 (1946-1947)
Highest: 7.78 (1948-1949)

Overall Winter Temperature (1895-2013)
Mean: 32.50°F
Median: 32.72°F
Standard Deviation: 1.99

Overall Winter Precipitation (1895-2013)
Mean: 6.43
Median: 6.39
Standard Deviation: 0.88

The winter temperature is below average, but within standard deviation for all of America, coast to coast. It is still chilly as it is below freezing. The Winter of 1935-1936 is one of the coolest winters on record, which suggest this winter could be quite cool, possibly the coolest since 2009-2010. I am not suggesting we are going to have a bitterly cold winter like in 2009-2010. In terms of rainfall for all of America, it is also within average. Let’s look at coldest winters for America from 1895-2013.

Coldest Winter For America (1895-2013)
1.) 1978-1979 26.72°F
2.) 1894-1895 27.00°F*
3.) 1935-1936 28.05°F
4.) 1898-1899 28.20°F
5.) 1909-1910 28.48°F
6.) 1904-1905 28.96°F
7.) 1928-1929 29.08°F
8.) 1977-1978 29.13°F
9.) 1917-1918 29.43°F
10.) 1916-1917 29.44°F
11.) 1911-1912 29.71°F

* December 1894 is missing from Divisional Data.

The winter of 1935-1936 is the third coolest winter on record! There was a cold wave that started in December 1935 to February 1936. Some states saw some of the coolest winters on record. I am not saying this could happen this winter, but it is a possibility. Interesting to see back to back cold winters like in the late 1910s and 1970s. America in those analog years can be abnormally dry or wet. Now, let’s look at the average and standard deviation for Texas based on anomaly of 1895 to 2013.

Texas Winter Analog
Temperature
Mean: 47.24°F
Median: 47.43°F
Lowest: 45.43°F (1935-1936)
Highest: 49.53°F (1952-1953)

Precipitation
Mean: 5.44
Median: 5.17
Lowest: 3.24 (1981-1982)
Highest: 8.60 (1960-1961)

Overall Winter Temperature (1895-2013)
Mean: 47.97°F
Median: 47.93°F
Standard Deviation: 2.29

Overall Winter Precipitation (1895-2013)
Mean: 5.10
Median: 4.93
Standard Deviation: 1.90

The winter temperature for Texas is slightly below average, but within average. Despite the slightly below average temperature, Texas has seen some huge freezes in those analog years. Many were hard freezes. Also, one of the coldest winters on record for Texas occurred in the analog year, 1935-1936. In terms of rainfall, it is wide range from 3.24 to 8.60 inches. Texas could see a wet winter, which is a good thing for the drought situation. Let’s look at coldest winters for Texas from 1895-2013.

Coldest Winter For Texas (1895-2013)
1.) 1894-1895 42.45°F*
2.) 1898-1899 42.50°F
3.) 1904-1905 42.87°F
4.) 1977-1978/1978-1979 43.23°F
5.) 2009-2010 43.30°F
6.) 1983-1984 43.77°F
7.) 1963-1964 43.80°F
8.) 1972-1973 44.37°F
9.) 1911-1912 44.50°F
10.) 1976-1977 44.87°F
11.) 1935-1936 45.43°F

* December 1894 is missing from Divisional Data.

Again, the winter of 1935-1936 is one of the coolest on record, like it is for America. If Texas is cold, than America is cold for the most part. Texas was quite cold in the winter of 1935-1936. Now, let’s look at the average and standard deviation for Upper Texas Coast based on anomaly of 1895 to 2013.

Upper Texas Coast Winter Analog
Temperature
Mean: 54.43°F
Median: 54.13°F
Lowest: 51.67°F (1935-1936)
Highest: 57.07°F (1948-1949)

Precipitation
Mean: 10.85
Median: 10.17
Lowest: 7.05 (1946-1947)
Highest: 17.20 (1960-1961)

Overall Winter Temperature (1895-2013)
Mean: 55.12°F
Median: 55.20°F
Standard Deviation: 2.63

Overall Winter Precipitation (1895-2013)
Mean: 10.72
Median: 10.21
Standard Deviation: 3.46

The Upper Texas Coast, which comprises of Houston, Galveston, and Beaumont also sees below average temperature. Again, like America and Texas, it is within standard deviation. It is also slightly wetter than average, but again not abnormally wet. It is wide range from 7.05 to 17.20, which raises the possibility of a wet winter. As mentioned, Houston area was hard hit by massive flooding from heavy rains in December 1935. Houston area had been hit by hard freezes in those analog years. Some of these freezes had lows in the teens and stayed freezing for more than 24 hours. The winter of 1935-1936 is also one of the coldest for Upper Texas Coast. Let’s look at coldest winters for Upper Texas Coast from 1895-2013.

Coldest Winter For Upper Texas Coast (1895-2013)
1.) 1977-1978 48.90°F
2.) 1894-1895 49.20°F*
3.) 2009-2010 49.63°F
4.) 1904-1905 49.83°F
5.) 1898-1899 50.13°F
6.) 1963-1964/1976-1977 50.23°F
7.) 1983-1984 50.57°F
8.) 1978-1979 50.70°F
9.) 1939-1940/1972-1973 51.03°F
10.) 1962-1963 51.43°F
11.) 1935-1936 51.67°F

* December 1894 is missing from Divisional Data.

Again, to see one of the coldest winter on record for Upper Texas Coast in the analog year, which is 1935-1936. Interesting to see some of the coldest winters happened back to back from like 1962 to 1964 and 1976 to 1979. The most recent coldest winter was 2009-2010. It was quite a cold winter.

The January 1928 freeze set records for Houston in low temperature and lowest high temperature on New Years Day 1928, which is yet to be beaten. The 1949 freeze had sub-zero temperature in Bryan/College Station and teens in Houston. January 1982 had lows near the single digit in Houston area. Snow and ice have fallen in those analog winters. Here are snow and ice records in Houston that fell in the analog winters.

Snow
January 30, 1949 2.6
January 25, 1961 Trace

Ice
January 25, 1961
February 24, 1965
January 12-14, 1982

There is a possibility that the freeze may bring snow and/or ice this winter. Again, I am not suggesting we will see that, but it is something to consider for this winter. The last time any snow fell in Houston was on February 23, 2010, when a trace fell. The last time there was an ice storm was February 4, 2011.

If we use statistics of analog seasons to forecast 2013-2014 Winter, this suggest a cooler and wetter winter for America, Texas, and Upper Texas Coast. If I was to go by rainfall total for this winter, it could certainly help the drought situation in some areas. I would not be surprised if there are some huge freezes this winter and some could be historic on par with February 1933, January/February 1949, January 1982, or even December 1989. These freezes were hard freezes.

When I see two warm winters back to back, the next one is likely to be cooler. However. there have been more than two warm winters back to back, which happened from 1998 to 2000. Two of the three occurred in La Nina, while one occurred in strong El Nino. The winter of 2000-2001 was quite cold.

As for North Atlantic Oscillation (NAO), Arctic Oscillation (AO), Pacific North American (PNA), and East Pacific Oscillation/North Pacific (EPO/NP), they change quickly as they are in the atmosphere. As for Quasi-Biennial Oscillation (QBO), it changes every 2 years. However, ENSO, PDO, and AMO can impact them. For example, cool PDO generally means negative PNA. However, there can be positive PNA during cool PDO. I believe the freezes we could see is going to be from a negative NAO and AO. Many freezes have occurred when NAO and AO went negative. A negative NAO and AO is when ridging occurs over Greenland, which allows cold air to go southward.

I will likely issue another winter forecast as I have a better idea of El Nino, PDO, and AMO will be like by December. Also, I should have a better idea for where the NAO, AO, PNA, and EPO/NP is heading.

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