2016-2017 Winter

Another winter has past. It is now spring again. We really had no winter with the exception of the Pacific Northwest where it got cold. Most of America was wondering where is winter. It felt like another spring. How did this winter stack up?

5 Kilometer Gridded Map Of Temperature Anomaly

Most of the US experienced warmer than normal winter. Some had record warmth winter, especially in Texas, Louisiana, Florida, and New Mexico. Washington, Oregon, and Idaho had cooler than normal winter. The mean temperatures tell you a lot. Of course, the devils are in the details.

5 Kilometer Gridded Map Of Minimum Temperature Anomaly

The low temperatures were quite warm in areas where they had record warmth. The areas that were cooler than normal had cooler low temperatures. No surprise there.

5 Kilometer Gridded Map Of Maximum Temperature Anomaly

The high temperature anomaly is not as large as compared minimum temperature anomaly. Low and high temperature can have an impact on overall mean temperature. One can have a cool winter if the low temperatures are high, while high temperatures are low or vice versa.

5 Kilometer Gridded Map Of Rainfall Anomaly

It was very wet, especially in California, Idaho, Wyoming, Utah, Texas, Iowa, and Alabama. Plenty of rain despite La Nina. It was a weak la Nina.

Here is a Northern Hemisphere temperature anomaly map.

Most of the Northern Hemisphere was warm, especially over the Arctic, North America, Asia, and Europe.

Here is a Northern Hemisphere precipitation anomaly map.

The wettest area is over Northern California where they go the lion share of the precipitation.

Here is a Northern Hemisphere 500 millibar level anomaly map.

There was ridging over the Southern US, Alaska, and Europe. The ridging kept things warm under. There is troughing over Northwest Canada, Pacific Northwest, Siberia, and Arctic. That kept things cold for winter.

Here is a worldwide sea surface temperature anomaly map.

The La Nina was weak, while Northeast Pacific off the coast of Alaska was mostly cooler than normal. There is unusually warm water in the Bering Strait and Gulf of Mexico.

America
Temperature: 35.90°F
Low Temperature: 25.94°F
High Temperature: 45.86°F
Rainfall: 8.22

1895-2017 Winter Statistics
Winter Temperature Mean: 32.37°F
Winter Temperature Median: 32.49°F
Standard Deviation: 2.06

Winter Low Temperature Mean: 21.91°F
Winter Low Temperature Median: 21.95°F
Standard Deviation: 2.13

Winter High Temperature Mean: 42.84°F
Winter High Temperature Median: 43.08°F
Standard Deviation: 2.10

Winter Rainfall Mean: 6.76
Winter Rainfall Median: 6.69
Standard Deviation: 0.89

It was an abnormally warm and wet winter. The temperature and rainfall are 1 standard deviation. This is abnormal in terms of temperature and rainfall. Here are the top 10 warmest and wettest winters in America.

Top 10 Warmest Overall Winter
1.) 2015-2016 36.78°F
2.) 1999-2000 36.48°F
3.) 1991-1992 36.35°F
4.) 2011-2012 36.34°F
5.) 1998-1999 36.27°F
6.) 1997-1998/2016-2017 35.90°F
7.) 2001-2002 35.66°F
8.) 1994-1995 35.56°F
9.) 2005-2006 35.49°F
10.) 2004-2005 35.46°F

Top 10 Warmest Low Temperature Winter
1.) 1997-1998 26.74°F
2.) 2015-2016 26.65°F
3.) 1991-1992 26.39°F
4.) 2016-2017 25.94°F
5.) 1982-1983 25.88°F
6.) 2011-2012 25.63°F
7.) 1994-1995 25.56°F
8.) 1998-1999 25.49°F
9.) 1999-2000 25.46°F
10.) 2004-2005 25.42°F

Top 10 Warmest High Temperature Winter
1.) 1999-2000 47.50°F
2.) 1998-1999 47.07°F
3.) 2011-2012 47.06°F
4.) 2015-2016 46.92°F
5.) 2001-2002 46.59°F
6.) 1953-1954 46.51°F
7.) 1933-1934 46.43°F
8.) 2005-2006 46.37°F
9.) 1991-1992 46.32°F
10.) 1980-1981 46.05°F
11.) 1975-1976 45.88°F
12.) 2016-2017 45.86°F

Top 10 Wettest Winter
1.) 1997-1998 8.99
2.) 1931-1932 8.86
3.) 1936-1937 8.66
4.) 1982-1983 8.52
5. 1996-1997 8.49
6.) 1978-1979 8.44
7.) 1902-1903 8.23
8.) 2016-2017 8.22
9.) 1915-1916 8.19
10.) 1992-1993 8.17

The overall temperature ties with 1998. The past winter of 2015-2016 is the warmest on record. The low temperature is the fourth warmest on record. The high temperature does not make the top 10 warmest. It shows that low temperatures can be a huge factor. The lack of cold air kept the low temperature warm. However, the wet winter kept the high temperature in check.

Texas
Temperature: 52.97°F
Low Temperature: 40.87°F
High Temperature: 65.07°F
Rainfall: 6.12

1895-2017 Winter Statistics
Winter Temperature Mean: 47.36°F
Winter Temperature Median: 47.30°F
Standard Deviation: 2.37

Winter Low Temperature Mean: 34.95°F
Winter Low Temperature Median: 35.10°F
Standard Deviation: 2.30

Winter High Temperature Mean: 59.75°F
Winter High Temperature Median: 59.50°F
Standard Deviation: 2.85

Winter Rainfall Mean: 4.83
Winter Rainfall Median: 4.72
Standard Deviation: 1.82

Top 10 Warmest Overall Winter
1.) 2016-2017 52.97°F
2.) 1906-1907 52.57°F
3.) 1999-2000 52.10°F
4.) 1998-1999 51.70°F
5.) 1951-1952 51.53°F
6.) 1949-1950 51.13°F
7.) 1956-1957 50.90°F
8.) 1910-1911 50.80°F
9.) 2015-2016 50.77°F
10.) 1908-1909 50.67°F

Top 10 Warmest Low Temperature Winter
1.) 2016-2017 40.87°F
2.) 1906-1907 39.50°F
3.) 1956-1957 39.23°F
4.) 1949-1950 39.10°F
5.) 1991-1992 39.07°F
6.) 2004-2005 39.00°F
7.) 1931-1932 38.87°F
8.) 1937-1938 38.80°F
9.) 1910-1911 38.77°F
10.) 1994-1995 38.57°F

Top 10 Warmest High Temperature Winter
1.) 1999-2000 65.77°F
2.) 1906-1907 65.57°F
3.) 2008-2009 65.23°F
4.) 2016-2017 65.07°F
5.) 1998-1999 64.97°F
6.) 1951-1952 64.77°F
7.) 2005-2006 64.63°F
8.) 1970-1971 64.53°F
9.) 1908-1909 64.23°F
10.) 1975-1976 64.03°F

Top 10 Wettest Winter

Texas had the warmest winter on record. The previous warmest winter was 1906-1907. The reason for the warm winter is largely due to abnormally warm low temperature, which is the warmest on record. The high temperatures is fourth warmest on record. 2000 is the warmest in terms of high temperature. All temperatures are 2 standard deviation, which is definitely abnormally and are out liers. However, rainfall is within 1 standard deviation, which is average.

Upper Texas Coast
Temperature: 61.73°F
Low Temperature: 52.73°F
High Temperature: 70.80°F
Rainfall: 12.25

1895-2017 Winter Statistics
Winter Temperature Mean: 54.06°F
Winter Temperature Median: 54.07°F
Standard Deviation: 2.72

Winter Low Temperature Mean: 44.22°F
Winter Low Temperature Median: 44.13°F
Standard Deviation: 2.80

Winter High Temperature Mean: 63.89°F
Winter High Temperature Median: 63.63°F
Standard Deviation: 2.86

Winter Rainfall Mean: 10.23
Winter Rainfall Median: 9.86
Standard Deviation: 3.51

Top 10 Warmest Overall Winter
1.) 2016-2017 61.73°F
2.) 1949-1950 59.57°F
3.) 1906-1907/1998-1999 58.87°F
4.) 1910-1911/1951-1952 58.77°F
5.) 1956-1957 58.73°F
6.) 1999-2000 58.63°F
7.) 1931-1932 58.30°F
8.) 1922-1923 58.07°F
9.) 2012-2013 58.00°F
10.) 1926-1927 57.93°F

Top 10 Warmest Low Temperature Winter
1.) 2016-2017 52.73°F
2.) 1949-1950 50.63°F
3.) 1931-1932 49.77°F
4.) 1956-1957 49.53°F
5.) 1910-1911 49.33°F
6.) 1998-1999 48.90°F
7.) 1951-1952 48.83°F
8.) 2011-2012 48.70°F
9.) 1922-1923 48.47°F
10.) 1971-1972 48.17°F

Top 10 Warmest High Temperature Winter
1.) 2016-2017 70.80°F
2.) 1906-1907 70.17°F
3.) 1999-2000 69.47°F
4.) 1998-1999 68.77°F
5.) 1951-1952 68.67°F
6.) 2008-2009 68.63°F
7.) 1949-1950 68.57°F
8.) 2007-2008 68.30°F
9.) 1910-1911 68.27°F
10.) 2012-2013 68.10°F

This was a very warm winter and literally abnormally warm. The overall temperature of 2016-2017 exceeds the previous warmest winter of 1949-1950 by 2.16°F! It exceeds by near 3 standard deviations! That is definitely an outlier! The low temperature is also the warmest and exceeds the previous warmest low temperature of 1949-1950. It also exceeds 3 standard deviations! However, the warmest high temperature is a close one. It is only by 0.63°F, which is not a lot. Still, it is 2 standard deviations, which in outlier territory. Winter 2016-2017 is an anomaly in terms of warm temperatures! It goes down in the record books! It was a wetter than usual winter, but within 1 standard deviation. It was due to the heavy rains of January.

Now, let’s look at the Last Frontier, Alaska.

Alaska Divisional Temperature Anomaly

Alaska Divisional Minimum Temperature Anomaly

Alaska Divisional Maximum Temperature Anomaly

Alaska Divisional Precipitation Anomaly

Temperature: 5.73°F
Low Temperature: -1.30°F
High Temperature: 12.80°F
Rainfall: 7.30

1925-2017 Winter Statistics
Winter Temperature Mean: 4.21°F
Winter Temperature Median: 4.57°F
Standard Deviation: 4.61

Winter Low Temperature Mean: -2.85°F
Winter Low Temperature Median: -2.90°F
Standard Deviation: 4.94

Winter High Temperature Mean: 11.26°F
Winter High Temperature Median: 11.67°F
Standard Deviation: 4.31

Winter Rainfall Mean: 8.13
Winter Rainfall Median: 7.91
Standard Deviation: 1.63

Alaska as a whole had a largely normal winter. The average temperature is within standard deviation. The precipitation is also within average as well. While the rest of the Lower 48 was warm, Alaska had a typically Alaskan winter. Even than Alaska can get cold and warm in the winter.

Top 10 Coolest Overall Winter
1.) 1924-1925 -7.20°F*
1.) 1964-1965 -5.03°F
2.) 1970-1971 -3.97°F
3.) 1955-1956 -3.10°F
4.) 1946-1947 -3.07°F
5.) 1942-1943 -2.77°F
6.) 1931-1932 -2.33°F
7.) 1933-1934 -2.23°F
8.) 1974-1975 -2.03°F
9.) 1975-1976 -1.83°F
10.) 1968-1969 -1.53°F

* December 1924 is missing.

Top 10 Warmest Overall Winter
1.) 2000-2001 14.97°F
2.) 2015-2016 14.30°F
3.) 2002-2003 13.43°F
4.) 1976-1977 12.80°F
5.) 2014-2015 11.60°F
6.) 1944-1945 11.30°F
7.) 1985-1986 11.27°F
8.) 1928-1929 11.23°F
9.) 1941-1942 11.03°F
10.) 1986-1987 10.80°F

Top 10 Coolest Low Temperature Winter
1.) 1924-1925 -15.25°F*
1.) 1964-1965 -12.50°F
2.) 1970-1971 -11.47°F
3.) 1955-1956 -10.80°F
4.) 1946-1947 -10.70°F
5.) 1931-1932 -10.60°F
6.) 1942-1943 -9.80°F
7.) 1933-1934 -9.63°F
8.) 1974-1975 -9.43°F
9.) 1975-1976 -9.30°F
10.) 1948-1949 -9.00°F

* December 1924 is missing.

Top 10 Warmest Low Temperature Winter
1.) 2000-2001 8.50°F
2.) 2015-2016 8.13°F
3.) 2002-2003 7.53°F
4.) 1976-1977 6.73°F
5.) 2014-2015 5.37°F
6.) 1985-1986 4.60°F
7.) 1944-1945 4.47°F
8.) 1941-1942 4.43°F
9.) 1928-1929 4.27°F
10.) 2013-2014 4.13°F

Top 10 Coolest High Temperature Winter
1.) 1924-1925 0.90°F*
1.) 1964-1965 2.50°F
2.) 1970-1971 3.53°F
3.) 1942-1943 4.27°F
4.) 1946-1947 4.57°F
5.) 1955-1956 4.60°F
6.) 1933-1934 5.20°F
7.) 1974-1975 5.30°F
8.) 1968-1969 5.33°F
9.) 1973-1974 5.63°F
10.) 1975-1976 5.67°F

* December 1924 is missing.

Top 10 Warmest High Temperature Winter
1.) 2000-2001 21.43°F
2.) 2015-2016 20.47°F
3.) 2002-2003 19.30°F
4.) 1976-1977 18.87°F
5.) 1928-1929 18.23°F
6.) 1944-1945 18.17°F
7.) 1985-1986 17.97°F
8.) 2014-2015 17.80°F
9.) 1941-1942 17.63°F
10.) 1986-1987 17.57°F

Top 10 Wettest Winter
1.) 1928-1929 11.89
2.) 1934-1935 11.55
3.) 1943-1944 11.26
4.) 1927-1928 10.88
5.) 1931-1932 10.78
6.) 1984-1985 10.65
7.) 2000-2001 10.61
8.) 1991-1992 10.38
9.) 1989-1990 10.26
10.) 1930-1931 10.22

Top 10 Driest Winter
1.) 1924-1925 3.12*
1.) 1968-1969 4.13
2.) 1929-1930 5.47
3.) 1949-1950 5.52
4.) 1977-1978 5.78
5.) 1973-1974 5.84
6.) 1933-1934 5.87
7.) 2009-2010 5.87
8.) 1981-1982 5.93
9.) 1972-1973 6.07
10.) 1935-1936 6.17

* December 1924 is missing.

The coldest winter since 1925 occurred in 1964-1965, while the warmest is 2000-2001. The wettest winter is 1928-1929, while driest is 1968-1969. Some of Alaska’s warmest winters occurred when the Lower 48 was cold. It shows if it is cold in the Lower 48, it is more likely to be warmer in Alaska. The cold air has to go somewhere. It is largely due to upper level ridging over Alaska, called the East Pacific Oscillation (EPO). It is largely affected by “The Blob”, which I created a data called the Northeast Pacific Warm Pool (NEPWP). The warmer the NEPWP is, the more negative EPO is.

Data came from Divisional Data Select, National Temperature and Precipitation Maps, and NOAA/NCEI Climate Division data: Mapping and Analysis Web Tool

It Is February And It Is Hot

February has been hot like summer. Yes, it is winter, but it feels like summer in Texas. Just look at the temperature anomaly map below.

surfaceairtemperatureanomaly_nh_20170206-20170212

Most of the cold air is over Alaska, Kazakhstan, and Central Russia. Now, why is it warm? We can look at the upper level at around 18,000 feet or 5,000 meters.

500mbgeopotentialheightanomaly_nh_20170206-20170212

There is ridging over most of America, Northern Europe, and Eastern Russia. There is troughing over Northwestern Canada, Japan, and Korea. The troughing keeps things cooler in that part of the world. Has it ever been this hot before in February? Yes, it has been and even reached 90°F in Southeast Texas. There were 100°F in South Texas. It occurred in 1986 and 1996.

Temperature Anomaly Map In 1986
surfaceairtemperatureanomaly_nh_19860218-19860220

Temperature Anomaly Map In 1996
surfaceairtemperatureanomaly_nh_19960221-19960223

Let’s look at the upper levels.

500 Millibar Geopotential Height In 1986
500mbgeopotentialheightanomaly_nh_19860218-19860220

500 Millibar Geopotential Height In 1996
500mbgeopotentialheightanomaly_nh_19960221-19960223

The pattern in 1986 and 1996 look similar. There is ridging over Lower 48 America, mostly over the southern half. There is ridging over Northeast Canada in 1986 and 1996, but not in 2017. There is troughing over Northwest Canada, Japan, and Korea. However in 1986 and 2017, there is ridging over Eastern Russia and Alaska, unlike in 1996 and 2017. There is also troughing over Northern Europe and Siberia in 1986. There is ridging over Northern Europe and Siberia in 1996 and 2017. Here is a composite of 1986, 1996, and 2017 upper air pattern at 18,000 feet or 5,000 meters.

500mbgeopotentialheightanomaly_nh_composite_february_heat_1986_1996_2017

There is ridging over most of America and troughing over Northwestern Canada, Japan, and Korea. There is ridging over Northern Europe, Northeast Canada, and Eastern Russia. Ridging over Eastern Russia is a negative West Pacific Oscillation (WPO), while over Alaska is East Pacific Oscillation (EPO). WPO and EPO are similar to North Atlantic Oscillation (NAO). Negative NAO has ridging over Northeast Canada and Greenland. Troughing over Northwest Canada favors negative Pacific North American Teleconnection (PNA) pattern. A negative PNA produces warmer winters. A negative WPO, EPO, and NAO favors cooler winters.

Another thing is 1986 and 1996 occurred in La Nina. The La Nina were weak that time. La Nina usually favors warmer winters because it is usually drier due to less rain. The most recent heat wave occurred in Neutral, not La Nina. A lot of things come to play from ocean to atmosphere to produce an abnormally warm February.

All the data is from NOAA-Daily Mean Composites.

2016-2017 Winter Forecast

Wow, time flies fast. Every year, time flies faster and it is almost Christmas. Winter is upon us again. Last winter we had a strong El Nino. This time around, we have Neutral conditions, neither La Nina or El Nino. Usually when there is a strong El Nino, La Nina follow. Not this time around. Other factors to consider are Pacific Decadal Oscillation (PDO), Atlantic Multidecadal Oscillation (AMO), Northeast Pacific Warm Pool (NEPWP), Roaring Forties, Equatorial Indian Ocean, and Tropical South Atlantic. However, since this El Nino is large and strong and has significant impact, it will weigh in more than other factors listed. Since, we have a strong El Nino, here are my analog winters. Here are the analog winters I came up with.

1878-1879
1897-1898
1900-1901
1912-1913
1919-1920
1926-1927
1931-1932
1958-1959
1983-1984
2003-2004

I chose these winters because the previous winter was El Nino as they are mostly strong El Nino’s. Those analog had weak La Nina or Neutral. Here is a table I created to identify strongest analogs.

Year ENSO Strong AMO PDO NEPWP EIOI TSAI R40I Total
1878-1879 1 1   1 1   1 5
1897-1898 1 1 1 1       4
1900-1901 1 1 1 3
1912-1913 1 1
1919-1920 1 1
1926-1927 1 1 1 3
1931-1932 1 1 1 1       4
1958-1959 1 1 1 1 1 1   6
1983-1984 1   1 1 1 1 1 6
2003-2004   1 1 1 1 1 1 6

I look at seven ocean patterns based on November averages. The cutoff for further analysis is four. We can eliminate these winters.
1900-1901
1912-1913
1919-1920
1926-1927

The analogs I will be looking at are
1878-1879
1897-1898
1931-1932
1958-1959
1983-1984
2003-2004

Let’s start with the ever important temperature. All divisional temperatures and rainfall were plotted with NOAA/NCDC Climate Division data: Mapping and Analysis Web Tool. All maps were generated with 20th Century Reanalysis Monthly Composites.

2016-2017_analog_divisional_temperature_standardizedanomaly-strongest-analog

This is a climate division map of the Lower 48. It does not have 1878-1879. Most of America saw cooler than normal winter, especially in Utah and Colorado. It is also colder in Texas. This would suggest a cooler than normal winter for most of America. The exception is in the Southeast where it is either normal or slightly warmer. What effects does it have around the world?

2016-2017_analog_wintertemperatureanomaly_world-strongest-analog

This one has 1878-1879. Alaska, Kamchatka Peninsula, Southeast Asia, India, Central Asia, and Arctic look to be cooler than normal. The Eastern Tip of Russia, Southeast US, Northeast Canada, North Central Siberia, Sudan, and Chad are warmer than normal. If one is wondering what the winter of 1878-1879 was like, here it is.

djf-1878-1879_wintertemperatureanomaly

It was cooler winter for North America with the exception of Northeast Canada and Greenland. It was also cooler throughout Siberia and Arctic. The NWS New York City has data from 1869 from Central Park. The first one is Normals and Extremes Central Park, NY (1869 to Present) and Average Monthly & Annual Temperatures at Central Park. The winter of 1878-1879 was a cold one with an average of 29.2°F. The average winter temperature in New York City is 35.1°F, which is 6 degrees below normal. The NWS Chicago shows a cooler than normal winter in 1878-1879, but not super cold. The previous winter of 1877-1878 is the warmest on record. It remains the warmest winter to this day. Chicago’s warmest winters occur in El Nino winters. No surprise there as the jet stream goes further south than usual. All Columbus, Ohio Data has the worst winters and 1878-1879 is considered one of the worst winters for Columbus. This would suggest that 1878-1879 was a cold winter for America including Texas.

The reason for 1878-1879 winter to be cold is due to negative North Atlantic Oscillation (NAO) and Arctic Oscillation (AO), which is ridging over Northeast Canada and Greenland. A positive NAO and AO is troughing over Greenland and Northteast Canada.

djf-1878-1879_winter500mbgeopotentialanomalynh

What does the upper level look like in analog winters?

2016-2017winter500mbgeopotentialanomalynh-strongest-analog

There is ridging south of Iceland, South of Bering Sea, and North Central Siberia. There is troughing over Eastern Russia, off the Eastern Seaboard of US, and Western Canada. This would suggest that cold blasts will be from the NAO rather than East Pacific Oscillation (EPO) and West Pacific Oscillation (WPO). It shows that if EPO and WPO are positive, while NAO is negative, there can be cold blasts. Keep in mind, EPO, WPO, and NAO can change quickly.

Wonder what winter will be like in the rain department?

2016-2017_analog_divisional_rain_standardizedanomaly-strongest-analog

From Texas to Maine, it looks to be wetter than normal. Same goes with part of the Midwest and Western US. California looks to be somewhat drier than normal. Again, this does not include 1878-1879, which I have included.

djf-1878-1879_winterprecipitationanomaly_world

Florida, California, Scandinavia, Iceland, Iran, Korea, Japan, and Western Canada were drier than normal in 1878-1879. It was very wet in Texas, Hawaii, Southwestern US, Caribbean, Spain, Portugal, France, Mediterranean region of Europe and Southwest Asia, and India in 1878-1879. Here is a worldwide map with the analogs.

2016-2017_analog_winterprecipitationanomaly_world-strongest-analog

It is the same general areas that are wet and dry. Interestingly, Western Canada is wetter, while Southwest is drier in analog winters. Texas has an average rainfall in analog winters.

How were winters like in these analog years? Were there cold blasts? Cold events are either in America or Texas. Rankings are temperature average since 1895.

1878-1879
Many areas in Northern US experience colder than normal winters.
1878 was a cold year for Europe, especially for United Kingdom.
The previous winter of 1877-1878 was very warm. In fact it is known as the year without winter in 1877.

Ranking
N/A

1897-1898
Reports of sleet fell on December 3-4, 1897 in Houston.
Cold blasts hits Houston in early January 1898. A low of 27°F on January 2, 1898.

Ranking
America’s 58th coldest winter on record.
Texas’s 63rd coldest winter on record.
Upper Texas Coast’s 47th coldest winter on record.

1931-1932
Houston was struck by a cold blast in March. Snow fell on March 10-11, 1932 in Houston. It remains the latest measurable snowfall to fall in Houston. A low of 27°F occurred on March 9, 10, and 13, 1932.

Ranking
America’s 104th coldest winter on record.
Texas’s 87th coldest winter on record.
Upper Texas Coast’s 89th coldest winter on record.

1958-1959
A cold blasts hits Texas in early January 1959. A low of 21°F was recorded on January 4, 1959 in Houston. Another cold blasts hits two weeks later with low of 25°F on January 22, 2016.

Ranking
America’s 38th coldest winter on record.
Texas’s 24th coldest winter on record.
Upper Texas Coast’s 20th coldest winter on record.

1983-1984
December 1983 had a huge cold blasts that set many records throughout America. Many areas experienced their coldest Christmas on record.

Ranking
America’s 19th coldest winter on record.
Texas’s 8th coldest winter on record.
Upper Texas Coast’s 10th coldest winter on record.

2003-2004
Northeast US was hit by cold blasts in January 2004. Boston had their coldest January since 1893. Many areas saw over 100 inches of snow, especially in Northern New York.
Snow fell in San Antonio and Austin on Valentine’s Day 2004.

Ranking
America’s 78th coldest winter on record.
Texas’s 88th coldest winter on record.
Upper Texas Coast’s 51st coldest winter on record.

I am not suggesting we will see a cold blast on par with December 1983 or January 2004. It is possible this winter could see a cold blast. Interesting to note that 1958-1959 and 1983-1984 were cold winters for America and Texas.

I think this winter could be a cooler winter. I would not be surprised to hear of a major cold blast this coming winter. It should be an interesting one for sure.

Challenger Disaster 30 Years Later

SpaceShuttleChallengerHeader

It is hard to believe it has been years ago on this day. Space Shuttle Challenger was launched on a cold morning. Than 73 seconds later it explodes as it is heading into space. To make matters worse, many children watched the space shuttle explode on live television. It was on CNN that time. The reason was that a teacher was on board, Christa McAuliffe. She was the first teacher on board the space shuttle. There were also people watching Challenger racing into space at Kennedy Space Center. January 28, 1986 is a day that anyone who remembers will remember as long as they live, like September 11, 2001. What caused Space Shuttle Challenger to explode? Was weather a factor?

Challenger was originally to be launched on January 22, but due to bad weather. Than it was rescheduled on January 25, but bad weather plagued Dakar, Senegal. Dakar serves as a Transoceanic Abort Landing (TAL) if the space shuttle is heading into space and runs into trouble. A lot of things go into play when the National Aeronautics and Space Administration (NASA) is planning to launch space shuttle. It is not just weather at Cape Canaveral. It is also TAL location weather.

A strong cold blast hit the Eastern US in late January 1986. The morning of January 28, 1986 was a cold one. Melbourne and Orlando both recorded 26°F, a record to this day for Melbourne. It was very cold in Florida. It was very cold for Florida and east of the Mississippi River.

19860128_TemperatureAnomalySurface_USA

To make matters worse, ice accumulated on the launch pad and space shuttle. This is despite the Ice Team cleared ice the night before. The Ice Team did one last inspection and it was declared safe to launch.

However, the O-ring in the Solid Rocket Boosters was damaged from the cold weather. The cold weather weakened the O-ring. Plumes of smoke from the Solid Rocket Boosters shoots as Challenger is launched at 11:38 AM. Aluminum oxide from the heat of the burning propellant sealed the hole where the O-ring was. Had aluminum oxide not form, Challenger would of exploded right at launch. Looks like the aluminum oxide saved Challenger from explosion.

ChallengerLaunch01

That all changed 37 seconds later, Challenger encounters unusually strong wind shear. The wind shear causes fluctuations and damages the aluminum oxide in the solid rocket boosters. This allowed smoke and fire to shoot out where the O-ring is suppose to be. Than a series of catastrophic events happen 72 seconds after Challenger was launched.

ChallengerLaunch02

The Solid Rocket Boosters starts to break away from the External Tank as the struts have been broken away. The flames point to the External Tank, which damages it, allowing hydrogen and liquid oxygen to come out. They all ignite and trigger a massive explosion. The massive explosion destroys Challenger with all seven crew members on board. It starts raining debris onto the Atlantic Ocean. Grace and Ed Corrigan watched their daughter, Christa McAuliffe die in the explosion. One cannot fathom the shock and grief they are going through as they watched their daughter die.

ChallengerExplosion01

ChallengerExplosion02

A stunned world watches Challenger exploding on television. It was only live on CNN that time, but other networks played Challenger exploding many times. The nation and world grieved for the seven people who died on board Challenger. President Ronald Reagan canceled the State Of The Union speech. He gave a speech addressing a shocked and grieving nation about the Challenger disaster.

What role did weather play in the Challenger disaster? It played a role. The O-ring was weakened by the record cold weather to hit Florida. That weakness was sealed due to the heat only to run into strong wind shear. It was the strongest wind shear encountered by a space shuttle that time. Had Challenger not encountered wind shear, the disaster would probably not have happened.

My verdict, Space Shuttle Challenger should of never been launched on January 28, 1986. The series of weather events played a role from the cold blast to wind shear. Space Shuttle launches have not occurred in cold weather prior to Challenger. Also, the engineers were horrified to see ice build up on the launch pad and space shuttle. That is very telling right there.

Here is a video of Space Shuttle Challenger launch on live television on CNN.

Christmas Storms

RowlettTornado01

It was a terrible Christmas for sure. The warm Chrsitmas last week made it felt like late Spring or early Summer. Christmas was very warm throughout America, east of the Rocky Mountains. The warm weather could not last forever in Winter. Cold air from the north came and it clashed with the warm air. That leads to severe weather including tornadoes.

Christmas2015_SurfaceTemperatureAnomaly_NA

The Eastern two thirds of America is abnormally warm. However, the warm and humid air by itself does not create storms. It needs lift. There is a large upper level trough to the west and upper level ridging to the east. That kind of setup is favorable for severe weather. The upper level trough brings in cold air from Canada and Alaska. The upper level ridging keeps things warm throughout America.

Christmas2015_500mb_GeopotentialHeightAnomaly_NA

The day before Christmas Eve, known as Festivus, severe weather hit the Southeast and Midwest. It mainly centered around Kentucky, Indiana, Arkansas, and Missouri. There were numerous reports of tornadoes, hail, and strong wind. Christmas Eve had tornadoes hit the Southeast, Alabama and Mississippi. Once the tornadoes and storms past, 15 people lost their life. It is not over yet.

Christmas2015TennesseeTornado01

Christmas2015TennesseeTornado02

Christmas sees more tornadoes and severe weather in the Southeast, again over Alabama. The tornadoes do not stop there. The day after Christmas, tornadoes strike the Dallas/Fort Worth Metroplex. A large EF-4 tornado hits Garland and Rowlett, destroying houses in its path. Once it is all over, 11 people lost their life.

RowlettTornado02

RowlettTornado03

Christmas2015Storm

There is also flooding from heavy rain. The heavy rain is mostly over Southeast Alabama, Southwest Missouri, Northeast Oklahoma, and Northwest Arkansas. The heavy rain is from the same storm system and warm air clashing. Many areas see 6 to 12 inches of rain in a 7 day period. Southeast Alabama saw as much as 19 inches of rain in 7 days! That is a lot for Winter! Then floodings have claimed at least 18 lives. Many areas in Missouri could see record flooding on par with 1973 and 1993.

20151228_7Day_Rainfall_Total

To make matters worse, there is an epic blizzard that hits New Mexico and West Texas. Many areas see 6 to 12 inches with isolated totals of 15 inches of snow. Talk about an epic blizzard right there!

Christmas2015ElPasoSnow

Christmas went from Fall, Spring, Summer, and Winter all at once! Talk about crazy weather! This is what El Nino can do to our weather. My Winter forecast had a higher chance for severe weather for the South and Southeast. I think this Winter will be known as the Winter of severe weather. It is not even January and February yet.

RowlettTornado04

This Christmas is a tragic one for 43 families. At least 43 people have lost their life in this severe storm. Thankfully, severe storms around Christmas are rare.

2015-2016 Winter Forecast

Snowman01

It is this time of the year. Winter is coming as Christmas is coming. It seems like Christmas comes sooner and sooner each year. One huge factor for this winter is the strong El Nino. It is one of the strongest El Nino since 1997-1998 if we go back to 1950. There were strong El Nino before 1950. 1877-1878, 1888-1889, 1896-1897, 1902-1903, 1904-1905, and 1940-1941 had strong El Nino.

Other factors to consider are Pacific Decadal Oscillation (PDO), Atlantic Multidecadal Oscillation (AMO), and now Northeast Pacific Warm Pool (NEPWP). However, since this El Nino is large and strong and has significant impact, it will weigh in more than other factors listed. Since, we have a strong El Nino, here are my analog winters.

1877-1878
1888-1889
1896-1897
1902-1903
1940-1941
1957-1958
1972-1973
1982-1983
1991-1992
1997-1998

I choose these analog years because they are strong El Nino regardless of Eastern Equatorial or Modoki or Central Pacific. I did not include 1904-1905, 1987-1987, and 1992-1993 because the peak happened in Spring, unlike right now. Since, I go by divisional climate data, there is nothing before 1895, but there are local climate data before 1895, but it would be tedious to look at. However, I can look at upper air pattern and temperature anomaly in those analog years thanks to 20th Century Reanalysis Monthly Composites, which has 20CRV2c.

2015-2016Winter500mbGeopotentialAnomalyWorld

It shows troughing south of Alaska, which is a positive East Pacific Oscillation (EPO). A positive EPO is less favorable for freezes. Now, that does not mean the EPO will always be positive because it can go negative. A negative EPO would have ridging over Alaska, which means a better chance for cold blasts in the winter. There is also ridging off the east coast of Japan and surrounding Antartica.

So, how does it affect temperature and rainfall? Let’s start with temperature.

2015-2016_Analog_WinterTemperatureAnomaly_World

The Northern part of America is warm as the jet stream travels further south than normal. It is also warm throughout South America as El Nino is off the coast of South America. It is cold in the Arctic and Antartica region. El Nino also effects rain.

2015-2016_Analog_WinterPrecipitationAnomaly_World

In terms of rainfall, Southern and Western US, West Coast of South America, Central Africa, Northern Pakisan/Afghanistan, and Southeast China is wetter than normal. The wettest is the area over where El Nino is. Meanwhile, most of Eastern South America, Philpppines, Indonesia, Northern Australia, Southeast Africa, Madagascar, and Central America are going to be dry. Droughts are usually a huge problem during El Nino for those areas.

Keep in mind temperature and rainfall records often do not go back to the 19th Century in many parts of the world. Let’s take a look at divisional climate in America. The data goes back to 1895, so there will be no data available prior to 1894, which means no data for 1877-1878 and 1888-1889. Let’s start with rainfall.

2015-2016_Analog_Divisional_Rain_StandardizedAnomaly

Rainfall is heavier to the south as mentioned previously due to jet stream. The jet steam carries more storm systems over the Southern US. Meanwhile, the Northern US is drier as a result. Generally it is wetter, but not always. Here is the wettest and driest analog years.

America
Driest: 1896-1897 6.68
Wettest: 1997-1998 8.99
Analog Mean: 7.61
Analog Standard Deviation: 0.87
Overall Mean (1895-2015): 6.74
Overall Standard Deviation (1895-2015): 0.88

Texas
Driest: 1896-1897 3.49
Wettest: 1991-1992 12.72
Analog Mean: 7.09
Analog Standard Deviation: 2.63
Overall Mean (1895-2015): 4.82
Overall Standard Deviation (1895-2015): 1.83

Upper Texas Coast
Driest: 1896-1897 5.30
Wettest: 1991-1992 23.54
Analog Mean: 13.18
Analog Standard Deviation: 5.24
Overall Mean (1895-2015): 10.24
Overall Standard Deviation (1895-2015): 3.53

1896-1897 was dry overall for America including Texas and Upper Texas Coast. The wettest is 1991-1992 and 1997-1998. Overall, analog years are wetter than normal. How does temperature fare?

2015-2016_Analog_Divisional_Temperature_StandardizedAnomaly

The Southern US is cooler than normal. It is due to the perpetual cloud coverage and rain, which keeps things cooler than normal. There can also be cold blasts during a strong El Nino. Up north is warmer than normal in the winter. Some people would like it as those areas are cold in the winter. Here is the warmest and coolest analog years.

America
Coolest: 1902-1903 30.03°F
Warmest: 1991-1992 36.35°F
Analog Mean: 33.55°F
Analog Standard Deviation: 2.29
Overall Mean (1895-2015): 32.31°F
Overall Standard Deviation (1895-2015): 2.01

Texas
Coolest: 1972-1973 43.83°F
Warmest: 1991-1992 46.90°F
Analog Mean: 46.90°F
Analog Standard Deviation: 1.89
Overall Mean (1895-2015): 47.28°F
Overall Standard Deviation (1895-2015): 2.31

Upper Texas Coast
Coolest: 1972-1973 50.13°F
Warmest: 1997-1998 55.93°F
Analog Mean: 53.47°F
Analog Standard Deviation: 1.09
Overall Mean (1895-2015): 53.97°F
Overall Standard Deviation (1895-2015): 2.63

America is warmer overall in those analog years. That is due to the Northern US being warmer than normal. Texas and Upper Texas Coast is cooler than normal due to all the rain and clouds over the Lone Star State. The combination and cooler and wetter weather increases the chance for winter weather for Southeast Texas. What about snow?

In Southeast Texas, snow has occurred in these analog years.
1896-1897
1957-1958
1972-1973

The data record from Houston Weather Bureau (WB) in January 1897 has handwriting I cannot read too well. It says that snow and a blizzard happened in Houston on January 25, 1897. There was a hard freeze from January 25-29. It did not go above freezing between January 26-29. It is a freeze in par with other huge freezes in January/February 1951 and February 1989 freezes! February 12, 1958 saw a snow flurry. The Winter of 1972-1973 had three snowfall events of over one inches. That is unheard in Houston area! It is also one of the coldest winters on record for Upper Texas Coast on par with 1977-1978 and 2009-2010. There is no weather record from 1877-1878 in Southeast Texas, so I do not know what the weather was like that time. 1888-1889 had no snowfall recorded. There were some freezes in January and February of 1889. It was more of a wet winter that time. This is from Houston WB records.

Another thing to consider is severe weather. I created a GIS heat map of tornado, hail, and strong wind for those analog years. The tornado, hail, and strong wind is from the 1950s and later. They are all within 300 miles. Let’s start with tornadoes.

2015-2016_Winter_Analog_Tornado

Tornadoes are generally rare in the Winter, but they can happen. In analog winters, tornadoes are most common from Southeast Texas, Louisiana, Arkansas, and Missouri. The second hot spot is Central Florida. El Nino causes the jet stream to go further south, allowing storms to track over. These storms dump heavy rain and can produce severe weather. Let’s look at strong winds from storms.

2015-2016_Winter_Analog_Wind

The entire Eastern US is most at risk for strong winds. Also, Central California is at most risk for strong winds. Strong winds can from severe thunderstorms and storm systems, a tight pressure gradient of low and high pressure, or a cold front passes. So, what effect does El Nino have on hail in the winter?

2015-2016_Winter_Analog_Hail

The highest risk for hail is Texas, Oklahoma, Arkansas, Louisiana, Southern Kansas, and Southern Missouri. There is also a higher risk in Alabama and Georgia and Southern Florida. Not a good thing as severe weather is generally more common in an El Nino winter in the Southern US.

The heat map could give us a good idea where severe weather events could happen this winter. Frankly, I would be just as concerned about severe weather, especially in the Southern US. I would not be surprised if this winter will be known as the winter of severe weather besides winter weather.

Past El Nino does not guarantee that this El Nino will be similar. All El Nino’s are different. Regardless, I expect an interesting winter coming. So fasten your seatbelt tightly. It will be a rough ride for sure.

2014-2015 Winter

Spring has arrived as days get longer each day. It has been a winter of really cold or warm. The Northeast basked in deep freezes and snow. The Western US was warm like if summer stayed. How did Winter 2014-2015 stack up? Let’s start with America.

America
Temperature: 34.44°F
Rainfall: 6.04

1895-2015 Winter Statistics
Winter Temperature Mean: 32.31°F
Winter Temperature Median: 32.48°F
Standard Deviation: 2.02

Winter Rainfall Mean: 6.74
Winter Rainfall Median: 6.69
Standard Deviation: 0.88

The average winter temperature is outside the standard deviation of the mean. It was an abnormally warm winter. The US had its 99th warmest winter on record, tying with 1932. In fact, it is in the top 20 warmest winters since 1895.

Top 20 Warmest Winter
1.) 1999-2000 36.48°F
2.) 1991-1992 36.35°F
3.) 2011-2012 36.34°F
4.) 1998-1999 36.27°F
5.) 1997-1998 35.90°F
6.) 2001-2002 35.66°F
7.) 1994-1995 35.56°F
8.) 2005-2006 35.49°F
9.) 2004-2005 35.46°F
10.) 1953-1954 35.33°F
11.) 1933-1934 35.28°F
12.) 1982-1983 35.27°F
13.) 1952-1953 35.25°F
14.) 1920-1921 34.80°F
15.) 1980-1981 34.73°F
16.) 1975-1976 34.59°F
17.) 1931-1932/2014-2015 34.44°F
18.) 1986-1987 34.42°F
19.) 2012-2013 34.32°F
20.) 1930-1931 34.03°F

How come despite the bitter cold winter in the Northeast. The Western US had a very warm winter. The Western US is much larger than the Eastern US. Here is a division temperature ranking.

2014-2015_WinterTemperatureDivisionalRanks

Notice the Eastern US had cold winters, while Western US had warm winters. I know that the Northeast had cold January and February as shown in this map.

201412_WinterTemperatureDivisionalRanks

201501_WinterTemperatureDivisionalRanks

201502_WinterTemperatureDivisionalRanks

Some areas had their coldest February on record. Winter came rather late. December 2014 was quite warm as seen this divisional map. It was like if winter did not want to come in December 2014.

So, why this happened you ask? Here is a upper level map at 18,000 feet of Northern Hemisphere.

2014-2015Winter500mbGeopotentialAnomaly

2014-2015_500mbGeopotentialHeightMean_NH

There is ridging over Alaska and Western US. The ridging over Alaska is the negative East Pacific Oscillation (EPO), West Pacific Oscillation (WPO), and positive Pacific North America Teleconnection (PNA). The ridging diverts cold air into the Northeast, where there is troughing. The persistant troughing allows cold air to come down south from the Arctic and Siberia. The troughing over Northeast Canada and Greenland is a positive North Atlantic Oscillation (NAO). Normally, a positive NAO favors warm winters for the US. However, since EPO and WPO are negative, while PNA is positive, it overpowered a positive NAO. It shows that NAO is not the only factor for cold winters. It is vice versa when NAO is very negative, while EPO and WPO are positive, while PNA is negative.

How did 2014-2015 Winter treat Texas?

Texas
Temperature: 47.77°F
Rainfall: 4.89

1895-2015 Winter Statistics
Winter Temperature Mean: 47.28°F
Winter Temperature Median: 47.27°F
Standard Deviation: 2.31

Winter Rainfall Mean: 4.82
Winter Rainfall Median: 4.72
Standard Deviation: 1.83

Winter was normal as it is close to the mean. It was nowhere like last winter, which was much colder. To make that up, it was wetter than last winter. More rain fell than last winter, which was a dry winter. That is a good thing as Texas is still reeling from the drought. How was the Upper Texas Coast like?

Upper Texas Coast
Temperature: 53.60°F
Rainfall: 9.64

1895-2015 Winter Statistics
Winter Temperature Mean: 53.96°F
Winter Temperature Median: 53.90°F
Standard Deviation: 2.63

Winter Rainfall Mean: 10.24
Winter Rainfall Median: 9.86
Standard Deviation: 3.53

Temperature and rainfall were within average even with a weak El Nino. There was snow in the Texas Panhandle and North Texas in February and even March. January was rather cold for the Upper Texas Coast. Despite it all, 2014-2015 was an average winter. A stark contrast from last winter for Texas, which was a cold and dry one.

So how did my forecast turn out? Let’s look at 2014-2015 temperature and precipitation.

2014-2015_WinterTemperatureAnomaly_NH

2014-2015_WinterPrecipitationAnomaly_NH

East of the Rocky Mountains was cooler, especially in the Northeast. The Western US was very warm like if Summer chose to stay in December. Also, Siberia was very warm, along with Europe. All the cold air went to the Eastern US this past winter. Many areas in the Western US had record warm winters for 2014-2015.

Most areas had near normal rainfall for Winter with the exception of British Columbia, Southern Mexico, and Mediterranean. The Western US drought situation is getting somewhat better. Better to have rain than no rain for sure.

Here’s the analog map for 2014-2015 Winter I created.

2014-2015_WinterTemperatureAnomaly_NH

2014-2015_WinterPrecipitationAnomaly_NH

The temperature anomaly for 2014-2015 looks similar to the analog temperature anomaly map, with the exception of colder winter over Siberia and Arctic. Some of those analog winters were very cold like 1972-1973, 1976-1977, and 2009-2010.

The precipitation anomaly map does not look similar in those analog winters. The exception is the Mediterranean and Southern Mexico, which had wet winters in those analog winters. The analog years for America have wet winters in the southern half of America. That was not the case for this past winter.

What could next winter be like? It could depend on how El Nino behaves. We are likely seeing a multi-year El Nino, which last happened in 1986 to 1988. A multi-year El Nino is much rarer than a strong El Nino like in 1982-1983 or 1997-1998. I should know more later this year.