Atlantic Hurricane Season In June

As we are in June and hurricane season is heating up. Where do most June tropical storms and hurricanes form and end up going?

Here is a GIS heat map I created. This is all June tropical storms and hurricanes from 1870 to 2015.

Most June tropical storms and hurricanes form in the Gulf of Mexico, Southwest Caribbean, and off the Carolinas. No surprise that Texas and Florida are most vulnerable to tropical storms and hurricanes in June.

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

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.

Why It Has Been So Warm So Far?

It has been so warm lately despite being October and Halloween is around the corner. It is like summer does not want to leave despite the calendar saying otherwise. Why is it so warm right now?

Let’s take a look at the upper atmosphere at the 500 millibar level or 18,000 feet.

20161030_500mbgeopotentialheightanomaly_nh_1021-1028

There is upper level ridging over the Lower 48. It is mainly over the Central US. The ridging prevents any cold air from coming down south. There is troughing off the Pacific Northwest, which has kept things wet for them, including California. There is also ridging over Alaska, which is a negative East Pacific Oscillation (EPO). A negative EPO normally supports cooler weather. However, the ridging over Central US is blocking any cold air. There is also troughing over Eastern Russia, which is a positive West Pacific Oscillation (WPO). WPO is similar to EPO as a negative EPO favors cold air being shunted down south. A positive WPO like positive EPO and North Atlantic Oscillation (NAO) keeps cold air from being shunted southward. There is also ridging centered around Yuzhny Island and Svalbard. It is a large area of ridging. I am surprised no one has created an index for that area. I suspect it is an oscillation like NAO and EPO. Would be interesting to check it out. Where are the cool and warm spots?

20161030_1000mbairtemperatureanomaly_nh_1021-1028

Not surprisingly, the warmest areas are where the ridging is most strongest. It is also very warm over the Arctic. The coldest area is over Central Asia, mainly over Kazazhstan. It is cold over most of Siberia. The Eastern tip of Russia is very warm. Rule of thumb, if there is upper level ridging, it will be warmer and drier, while upper level troughing will be cooler and wetter. The upper level trough has deep cold air, there can also be snow fall. Case in point, let’s look at two snow events in Southeast Texas; February 12, 1960 and December 10, 2008. February 12, 1960 is the biggest snowfall event since February 14-15, 1895. The December 10, 2008 gave Houston an early start in the snowfall department before places that see snow like Chicago and New York. Let’s start with 1960.

19600212_500mbgeopotentialheightanomaly_usa

There is a deep trough over Mexico and is moving eastward towards Texas before the February 12, 1960 snowfall. It is a very large upper level trough.

19600212_500mbairtemperatureanomaly_usa

The trough has deep layer of cold air. That is very favorable for snowfall. Snow happens when there is a deep layer of cold air. One reason why snow can fall at above freezing temperature. Shallow layer of cold air is not conducive for snowfall. More likely there will be sleet or freezing rain. One reason why Southeast Texas does not get snow often is cold air is shallow, not deep. Let’s also look at December 10, 2008 snowfall.

20081210_500mbgeopotentialheightanomaly_usa

The trough in the 2008 snow event is smaller than the 1960 snowfall event.

20081210_500mbairtemperatureanomaly_usa

Like the 1960 event, it also had deep layer of cold air. If one wants to compare February 1960 snowfall, the closest is December 2008 in terms of atmospheric setup. Perhaps we will see snow this winter.

Spring 2016 Report

Flower01

It is deja vu! Spring 2016 was wet like Spring 2015 despite El Nino fading. To make matters worse, there was severe flooding in April and May, which dumped up to 24 inches of rain in both events! That is something you see with tropical cyclones or core rain events with warm core low pressure systems. They are often from tropical cyclones.

For Texas, it has been mostly wet. For others, where’s the rain?

2016_SpringPrecipitationDivisionalRanks

2016_SpringTemperatureDivisionalRanks

America 2016 Spring
Mean Temperature: 53.68°F
Total Rainfall: 9.03

America Spring Temperature (1895-2016)
Mean: 51.10°F
Median: 50.87°F
Standard Deviation: 1.39
Lowest: 56.18°F (2012)
Highest: 47.37°F (1917)

America Spring Rainfall (1895-2016)
Mean: 7.95
Median: 7.95
Standard Deviation: 0.98
Lowest: 5.58 (1925)
Highest: 10.40 (1991)

It was a warm spring, but not a record breaking spring for America. It is nowhere like 2012. The average temperature is 1 standard deviation from the mean in terms of temperature. That is unusual, but not extraordinarily warm. If it was 2 standard deviation or greater that would be abnormal. It was abnormally warm for spring time in America.

It was much wetter as a whole. In fact, the Spring 2016 rainfall total is exceeds by 1 standard deviation. It was a wet spring for most of America.

Texas 2016 Spring
Mean Temperature: 66.27°F
Total Rainfall: 11.90

Texas Spring Temperature (1895-2016)
Mean: 64.76°F
Median: 64.73°F
Standard Deviation: 1.76
Lowest: 69.67°F (2012)
Highest: 59.93°F (1931)

Texas Spring Rainfall (1895-2016)
Mean: 7.37
Median: 7.05
Standard Deviation: 2.34
Lowest: 2.53 (2011)
Highest: 16.48 (2015)

It was warmer than normal for spring in Texas. It is 1 standard deviation from the mean.

It is wet, but not like 2015, which was wetter. Actually, it is the eighth wettest spring on record as it ties with 1914. It was indeed a wet spring for Texas, like last spring. Having two wet springs back to back is a rarity. Here is the top 10 wettest spring in Texas since 1895.

Top 10 Wettest Spring In Texas
1.) 2015 16.48
2.) 1957 14.75
3.) 1905 12.59
4.) 1941 12.43
5.) 1900 12.36
6.) 2007 12.16
7,) 1922 11.97
8.) 1914/2016 11.90
9.) 1997 10.85
10.) 1929 10.79

Many of the wettest springs occurred when El Nino is developing (1914, 1957, 1997, and 2015), persistent (1905 and 1941) or dying (1900 and 2007). 1922 was La Nina, while 1929 was Neutral. It shows that El Nino does have an impact on spring rainfall,whether is strengthening or dying. Interesting to note hurricanes made hurricanes made landfall in 1900, 1929, 1941, 1957, and 2007. Two were major hurricanes, Galveston Hurricane and Audrey in 1957.

Upper Texas Coast 2016 Spring
Mean Temperature: 71.07°F
Total Rainfall: 20.77

Upper Texas Coast Spring Temperature (1895-2016)
Mean: 68.54°F
Median: 68.42°F
Standard Deviation: 1.69
Lowest: 72.83°F (2012)
Highest: 63.37°F (1931)

Upper Texas Coast Spring Rainfall (1895-2016)
Mean: 10.58
Median: 10.02
Standard Deviation: 4.53
Lowest: 2.43 (2011)
Highest: 24.75 (2015)

It has been a warm spring. It is nearly 2 standard deviations from the mean. It was abnormally warm spring. It is the eighth warmest spring for Upper Texas Coast. Here is the top 10 warmest spring in Texas since 1895.

Top 10 Warmest Spring In Upper Texas Coast
1.) 2012 72.83°F
2.) 2011 72.03°F
3.) 2006 72.00°F
4.) 2000 71.57°F
5.) 1967 71.43°F
6.) 1963 71.40°F
7.) 1908 71.37°F
8.) 2016 71.07°F
9.) 1991 71.00°F
10.) 1925 70.97°F

Spring 2012 was warm everywhere, especially up north. 2011 was very warm as well. Who could forget Summer 2011? It was Hell for sure, which was made worse by the drought. The warmth is due to abnormally warm low temperatures. All that heavy rain makes the air more humid. Humidity keepers temperatures from going too cold or hot. It is the seventh warmest low temperature for spring. Here is a divisional ranking map of low and high temperatures.

2016_SpringMinTemperatureDivisionalRanks

2016_SpringMaxTemperatureDivisionalRanks

It was very west for Upper Texas Coast. It exceeds 2 standard deviations, which makes a near outlier. In fact, it is the third wettest spring on record! Yes, third wettest. There have been two back to back wet springs in the Upper Texas Coast. Here is the top 10 wettest spring in Upper Texas Coast since 1895.

Top 10 Wettest Spring In Upper Texas Coast
1.) 2015 24.75
2.) 1997 22.18
3.) 2016 20.77
4.) 1900 19.54
5.) 1957 19.32
6.) 1929 19.06
7.) 1914 18.54
8.) 1944 18.33
9.) 1993 18.32
10.) 1905 17.60

Many of the wettest springs for Upper Texas Coast occurred when El Nino is developing (1914, 1957, 1997, and 2015), persistent (1905) or dying (1900). 1944 had a developing La Nina from Neutral. 1929 was Neutral. April and May 1929 had heavy rain that led to massive flooding in the Houston area. The 1929 flood is considered an epic flood on par with December 1935 and Tropical Storm Allison in 2001. It shows that El Nino does have an impact on spring rainfall,whether is strengthening or dying. Interesting to note hurricanes made hurricanes made landfall on Upper Texas Coast in 1900, 1929, and 1957. Two were major hurricanes, Galveston Hurricane and Audrey in 1957.

Could this be a harbinger of things to come? America has not seen a Category 3 or stronger hurricane since Wilma in 2005. Now, if we lowered Category 3 by 1 mph from 111 mph to 110 mph, than Ike would be a major hurricane. Even than, America has not seen a major hurricane make landfall since 2008, which is a long stretch. Keep in mind, hurricane re-analysis is happening, so this long stretch of no Category 3 or stronger hurricanes we are seeing may not be the longest.

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.

The Tropical Atlantic Is Heating Up For 9/13/2015

We are in mid September and the tropics are heating up. There are three areas of interest in the tropics; Invest 93L, 94L, and 95L.

20150915_GOES-EAST_TATL_AVN_0145Z

Invest 94L is the closest to Texas. 94L has a low chance of development. It is close to land and has to contend with wind shear. Here is the 5 day forecast of where 94L will go.

20150915_Invest94L_0000Z

Most have it going to Mexico. One has it going into Texas, which is an outlier. Another has it going south into the Yucatan Peninsula. I do not think 94L will become tropical. Even the intensity forecast models do not support it.

20150915_94L_Intensity_0000Z

Most forecast models have 94L below tropical depression. A couple of models have it as a tropical storm in the next two days. Two models have 94L as a tropical storm in five days. Forecasting intensity has a long way to go.

Verdict: Invest 94L will not develop into something tropical.

Now, let’s go to Invest 93L. I think this one could develop in the next couple of days if conditions are right. It has to deal with wind shear and dry Saharan air, which has been persistent due to El Nino. The forecast models are hinting it could become a named storm within 24 hours. It would be Ida.

20150915_93L_Intensity_0000Z

I am not too sure if 93L will develop. If so, it will probably develop into a tropical storm at most.

20150915_Invest93L_0000Z

Most forecast models keep 93L out to sea. When a storm intensifies into in the middle of the Atlantic, they tend to be more influenced by upper air patterns. This holds true with hurricanes.

Verdict: Invest 93L could develop, but will not hold my breath for it.

Finally, let’s look at Invest 95L. It just came off of West Africa. 95L has a better chance of developing in the next five days. One thing about Invest 93L, it has to also deal with dry air. That could favor 95L as it can intensify. I think 95L could become Ida or Joaquin, which ever develops first.

20150915_95L_Intensity_0000Z

Some of the forecast models have 95L as a hurricane in the next two to three days. It peaks as a Category 2 hurricane. If Ida was to develop, I would not be surprised if 95L became a Category 3 hurricane. Now, where does it go?

20150915_Invest95L_0000Z

Invest 95L has a more west northwest direction. Even five days later, it is still in the middle of the Atlantic. Could it pose a threat to land? Depending how fast it develops. The slower it develops, the better chance that it could pose a threat to land.

Verdict: Invest 95L is the one to watch this week.

We are in the peak month of hurricane season. So, the tropics are heating up.