Monsterous Michael Makes Landfall

History was made earlier today. Hurricane Michael made landfall as a Category 4 hurricane with 155 mph 135 knots 249 km/h. The highest wind on land is around 132 mph 115 knots 212 km/h with gusts as high as 198 mph 172 knots 319 km/h! It has a central pressure of 919 millibars and still intensifying! If it had been over water longer, it probably would of been a Category 5 hurricane. No doubt that Michael made history. Here is how Michael compares to past hurricanes.

Michael is the most intense Gulf Of Mexico hurricane since Rita (2005). Rita had a central pressure of 895 millibars with 180 mph 156 knots 290 km/h. Rita is the most intense Gulf Of Mexico hurricane recorded. There is no doubt there are stronger Gulf Of Mexico hurricanes that go unrecorded prior to the 19th century. Rita made landfall on the Texas and Louisiana border not before triggering a massive evacuation due to Katrina ravaging the Gulf Coast a month earlier. Michael is the most intense October Gulf Of Mexico hurricane since Opal (1995). Opal had a central pressure of 916 millibars and 150 mph 130 knots 241 km/h winds. Opal made landfall on Pensacola.

How does Michael stack up in terms of central pressure landfall for America and Atlantic Basin? Michael is the third most intense landfalling hurricane on America. Only the 1935 Labor Day and Camille have lower central pressures.

Rank Storm Landfall Pressure
1 Labor Day (1935) 892 mb
2 Camille (1969) 900 mb
3 Michael (2018) 919 mb
4 Katrina (2005)/Maria (2017) 920 mb
5 Andrew (1992) 922 mb
6 Indianola (1886) 925 mb
7 Guam (1900) 926 mb
8 Florida Keys (1919) 927 mb
9 Okeechobee (1928) 929 mb
10 Great Miami (1926)/Donna (1960) 930 mb

Michael has lower pressure than Katrina, Maria, and Andrew. Michael is the most intense Category 4 hurricane to make landfall on America. Katrina is the most intense Category 3 hurricane to make landfall on America. Katrina is much larger than Camille, Andrew, or Michael, which explains the low pressure and Category 3 winds. Texas’s most intense hurricane recorded is the 1886 Indianola Hurricane, which had a central pressure of 925 millibars. It is likely it had lower pressure. The 1900 Guam typhoon is the most intense typhoon recorded to hit Guam. It is very likely there have been more intense typhoons that hit Guam. Typhoons are often intense and often have lower pressure than the Atlantic. Category 5 typhoons happen every year. Let’s look at how Michael compares Atlantic Basin.

Rank Storm Landfall pressure
1 Labor Day (1935) 892 mb
2 Camille (1969)/Gilbert (1988) 900 mb
3 Dean (2007) 905 mb
4 Cuba (1924) 910 mb
5 Janet (1955)/Irma (2017) 914 mb
6 Cuba (1932) 918 mb
7 Michael (2018) 919 mb
8 Katrina 2005/Maria (2017) 920 mb
9 Bahamas (1932) 921 mb
10 Andrew (1992) 922 mb

Michael ranks seventh most intense basinwide hurricane landfall! The 1935 Labor Day Hurricane is still the most intense basinwide landfall. Camille (1969) and Gilbert (1988) tie as second most intense landfall basinwide. There is a unconfirmed report that the 1935 Labor Day Hurricane had pressure as low as 880 millibars! If that was true, it would be the most intense Atlantic hurricane, even surpassing Wilma!

Michael is one of the few Category 4 hurricanes to make landfall in October. Here is a list of hurricanes that made landfall on America in October.

1893 “Chenier Caminanda”
1898 Georgia Hurricane
1950 King
1954 Hazel

The last hurricane to make landfall on America as a Category 4 is Hazel in 1954. On top of it, Michael is a major hurricane over Georgia. The last time Georgia saw a major hurricane was in 1898! It is from the Georgia Hurricane.

History and statistics aside, we are going to be hearing and seeing a lot of destruction and likely more deaths from Michael. It could be a very costly hurricane 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.

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.


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.




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.



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?

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.



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.



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.

2013-2014 Winter


BRRRRRRR!!!!!!!!! It was a cold and snowy winter for many. For some, they ask, “Where is winter?” as it felt like that winter never came. This winter has been certainly cold compared to recent winters of 2011-2012 and 2012-2013. So, how cold was this winter?

Temperature: 31.27°F
Rainfall: 5.69

1895-2014 Winter Statistics
Winter Temperature Mean: 32.29°F
Winter Temperature Median: 32.47°F
Standard Deviation: 2.01

Winter Rainfall Mean: 6.74
Winter Rainfall Median: 6.69
Standard Deviation: 0.89

It has been quite cold for America. A far cry from last two winters, which were balmy. Winter did not want to come. So, why was this past winter cold? The reason is the North Pacific Oscillation (NPO) or East Pacific Oscillation (EPO). Like North Atlantic Oscillation (NAO) and Arctic Oscillation (AO), when EPO goes negative, it causes upper level ridging over Alaska, which allows cold air to go down south. Even if EPO is negative, while NAO and AO are positive, America gets cold. This setup happened in December 1983 and February 1989, where deep freezes hit America.


Winter rainfall has been below average. This is mainly due to the dry winter in the Western US. So, how does 2013-2014 rank? Let’s look at top 20 coldest winter since 1895.

Top 20 Coldest Winter
1.) 1978-1979 26.61°F
2.) 1894-1895 26.65°F*
3.) 1935-1936 27.78°F
4.) 1898-1899 27.95°F
5.) 1909-1910 28.17°F
6.) 1904-1905 28.69°F
7.) 1928-1929 28.72°F
8.) 1977-1978 29.04°F
9.) 1916-1917 29.10°F
10.) 1917-1918 29.11°F
11.) 1911-1912 29.35°F
12.) 1903-1904 29.89°F
13.) 1976-1977 30.01°F
14.) 1902-1903 30.03°F
15.) 1948-1949 30.14°F
16.) 1936-1937 30.35°F
17.) 1914-1915 30.39°F
18.) 1963-1964 30.40°F
19.) 1983-1984 30.56°F
20.) 1919-1920/1984-1985 30.57°F

*December 1894 data is missing.

Notice there have been some data change for climate division, so the value and ranking is a little different. For example, Winter 2009-2010 was 15th coldest winter on record and now it is 22nd coldest on record. Winter 2013-2014 does not make the top 20 list. It is the 34th coldest winter on record. It is cold considering that last winter was 19th warmest winter on record. Quite a stark contrast right there. Interesting to note that some of the coldest winter occurred in the same decade, 1910s and 1970s and some occurred back to back in the early 1900s, mid to late 1910s, and late 1970s.

Since, this winter had been dry, how does 2013-2014 fare in the rainfall department. Here is a top 10 driest winter on record.

Top 10 Driest Winter
1.) 1976-1077 4.17
2.) 1930-1931 4.68
3.) 1980-1981 4.72
4.) 1894-1895 4.73*
5.) 1962-1963 4.88
6.) 1946-1947 5.40
7.) 1963-1964 5.47
8.) 1919-1920 5.63
9.) 1903-1904 5.68
10.) 2001-2002/2013-2014 5.69

*December 1894 data is missing.

I got the winter rainfall forecast way off. 2013-2014 is the 10th driest on record and ties with 2001-2002, which had little snow on the East Coast. That lack of snow contributed to the clean up of what used to be the World Trade Center, which tragically was destroyed on September 11, 2001 by terrorists. Initially, it was feared that it could take up to two years to clear the World Trade Center site. The dry winter is due to the severe drought in the Western US, especially in California. If I was in California, I would be more worried about drought than earthquakes. At least earthquakes happen quickly, while droughts are prolonged. Also, droughts can happen anywhere in the world, whether desert or tropical rainforest. A huge earthquake can only happen in areas with active fault lines, which is Pacific Rim or South Asia due to India subcontinent moving further north.

Now, let’s look at the great state of Texas’s winter.

Temperature: 45.93°F
Rainfall: 2.42

1895-2014 Winter Statistics
Winter Temperature Mean: 47.28°F
Winter Temperature Median: 47.22°F
Standard Deviation: 2.32

Winter Rainfall Mean: 4.82
Winter Rainfall Median: 1.83
Standard Deviation: 4.68

It was even cold in the Lone Star State. The cold weather may have kept things dry as it is below standard deviation as I will look soon. It makes an abnormally dry winter. That is concerning as drought is a major problem in Texas. So, how does 2013-2014 rank in Texas?

Top 20 Coldest Winter
1.) 1898-1899 41.33°F
2.) 1894-1895 41.55°F*
3.) 1904-1905 42.20°F
4.) 1978-1979 42.83°F
5.) 1977-1978 42.87°F
6.) 1963-1964 43.03°F
7.) 1911-1912 43.43°F
8.) 1983-1984 43.50°F
9.) 1972-1973/2009-2010 43.83°F
10.) 1909-1910 44.23°F
11.) 1917-1918 44.30°F
12.) 1976-1977 44.50°F
13.) 1935-1936 44.53°F
14.) 1962-1963 44.57°F
15.) 1912-1913 44.63°F
16.) 1960-1961 44.67°F
17.) 1914-1915 44.80°F
18.) 1928-1929 44.87°F
19.) 1905-1906 44.90°F
20.) 1947-1948 44.93°F

*December 1894 data is missing.

This winter is not in the top 20 coldest winter as it ranks 27th coldest on record for Texas. It makes the top 30 coldest winter on record. It is the coldest winter since 2009-2010 and that winter was cold. On the topic of rainfall, it was bone dry. That is a very concerning as Texas has been in a drought since 2008. So, how does 2013-2014 compare in the rainfall deparment?

Top 10 Driest Winter
1.) 2008-2009 1.54
2.) 1908-1909 1.67
3.) 1917-1918 1.72
4.) 1970-1971 1.80
5.) 1916-1917 2.11
6.) 1966-1967 2.12
7.) 1975-1976 2.13
8.) 1995-1996 2.31
9.) 1901-1902 2.32
10.) 2013-2014 2.42

The 2013-2014 Winter is tenth driest on record. The most recent dry winter is also the driest on record, 2008-2009. This past winter is even drier than 2010-2011 and that was a strong La Nina. This past winter was Neutral bordering into La Nina. It shows that El Nino or La Nina is not only factor for winter rainfall and temperature. There are other factors in play. In the meantime, let’s check out the Upper Texas Coast, which Houston is in.

Upper Texas Coast
Temperature: 52.17°F
Rainfall: 4.36

1895-2014 Winter Statistics
Winter Temperature Mean: 53.96°F
Winter Temperature Median: 53.98°F
Standard Deviation: 2.64

Winter Rainfall Mean: 10.24
Winter Rainfall Median: 9.88
Standard Deviation: 3.54

Top 20 Coldest Winter
1.) 1894-1895 47.85°F*
2.) 1977-1978 48.07°F
3.) 1898-1899 48.90°F
4.) 1963-1964 49.03°F
5.) 1904-1905 49.17°F
6.) 1976-1977 49.60°F
7.) 2009-2010 49.67°F
8.) 1978-1979 49.87°F
9.) 1962-1963 50.03°F
10.) 1983-1984 50.07°F
11.) 1911-1912/1972-1973 50.13°F
12.) 1939-1940 50.33°F
13.) 1935-1936 50.50°F
14.) 1905-1906 50.63°F
15.) 1909-1910 50.93°F
16.) 1917-1918 51.13°F
17.) 1967-1968 51.20°F
18.) 1959-1960 51.30°F
19.) 1947-1948/1960-1961 51.37°F
20.) 1958-1959 51.43°F

*December 1894 data is missing.

Like America and Texas, the Upper Texas Coast did not crack top 20 coldest winter. It is the 26th coldest winter on record. It is cold for sure, much colder than the past two winters. 2009-2010 was much colder than 2013-2014 despite more freezing temperatures than in 2009-2010. 2009-2010 had below average temperatures every single day. Winter 2009-2010 still remains in the top 10 coldest winter on record.

The past few months had below normal temperature. In terms of rainfall, it has been dry. The analog precipitation forecast was way off for Upper Texas Coast. The winter rainfall total is well below standard deviation of 3.54. That is very concerning as drought remains a problem. However, I was right in regards of winter precipitation as Houston saw five freezing rain events. Here is how 2013-2014 compared for Upper Texas Coast.

Top 10 Driest Winter
1.) 2008-2009 2.83
2.) 1917-1918 3.93
3.) 1970-1971 4.05
4.) 2013-2014 4.36
5.) 1908-1909 4.48
6.) 1961-1962 4.97
7.) 1896-1897 5.30
8.) 1975-1976 5.63
9.) 1903-1904 5.74
10.) 1985-1986 5.77

The 2013-2014 Winter is fourth driest on record. For the record, the Winter of 2008-2009 is driest on record since 1895. Driest winters occur usually during a La Nina and we were Neutral. This is very concerning as drought has stricken a good portion of Texas and America. However, I see light at the end of the tunnel. El Nino is developing and word is it could be a strong one like 1982-1983 or 1997-1998. If that is the case, we could see a wet spring or summer and certainly a wet fall and winter. That would be a good thing as it can bring the drought to a screeching halt.

2012-2013 Winter Report Progress Report


Meteorological Winter of 2012-2013 has passed into memory lane. Time flies fast as Christmas felt like yesterday and it is almost Easter. So, how did Winter 2012-2013 stack up?

Temperature: 34.36°F
Rainfall: 7.10

1895-2013 Winter Statistics
Winter Temperature Mean: 33.01°F
Standard Deviation: 1.99

Winter Rainfall Mean: 6.43
Standard Deviation: 0.88

America had the 24th warmest winter on record. Quite warm if you think about it. This winter was cooler as last winter. 2011-2012 Winter was the 5th warmest winter on record. A winter without much snowfall, which gave way to drought and warm year in 2012.

If there is a consolation prize for this winter, it was a wetter than normal winter on top of more snow. America had the 22nd wettest winter on record. That is an improvement from last winter, which had the 24th driest winter on record. It is rain that is needed to put a dent on the drought.

Temperature: 50.07°F
Rainfall: 4.93

1895-2013 Winter Statistics
Winter Temperature Mean: 47.97°F
Standard Deviation: 2.29

Winter Rainfall Mean: 5.10
Standard Deviation: 1.90

Texas had quite a warm winter as it was above the standard deviation. Texas had the 18th warmest winter on record, which puts it in the top 20 warmest winter from 1895 to 2013. The previous winter had the 35th warmest winter on record. 2011-2012 winter was cooler than the winter of 2012-2013.

Texas had the 55th wettest winter on record. Last winter, Texas had the 10th wettest winter on record. Quite a stark contrast if you think about it. A wet winter gives a cooler winter as there are cloud cover and moisture in the air that moderates the temperature. The rainfall amount is within the normal range as it is within standard deviation. Texas could use more rain to put an end to the drought plaguing Texas.

Upper Texas Coast
Temperature: 58.07°F
Rainfall: 11.45

1895-2013 Winter Statistics
Winter Temperature Mean: 55.12°F
Standard Deviation: 2.63

Winter Rainfall Mean: 10.72
Standard Deviation: 3.46

Upper Texas Coast had the 16th warmest winter on record. It was warm even by Southeast Texas standard, even though they have mild winters. Last winter, the Upper Texas Coast had the 18th warmest winter on record. Another warm winter for the record book and back to back, like in 1998-1999 and 1999-2000. The Ghost of Winter Past did not want to leave the Upper Texas Coast.

The Upper Texas Coast had the 42nd wettest winter on record. Last winter, Upper Texas Coast had the 14th wettest winter on record, which occurred in a La Nina winter. Upper Texas Coast is drier than last year. However, in terms of rainfall, Upper Texas Coast had a normal rainfall as it is within the standard deviation. It is still concerning as there has not been a lot of rain lately as Upper Texas Coast is seeing droughts developing.


So, how did my winter forecast hold up? It held up for the most part. East of the Continental Divide had warmer than normal winters, while west of the Continental Divide and Hawaii were cooler. However, Alaska, Western Canada, and Northeastern Canada was warmer than normal. The analog winters of 1951-1952, 1963-1964, and 2001-2002 have Alaska, Western Canada, and Northeastern Canada cooler than normal. In terms of rainfall, it was much wetter in the Midwest, Great Lakes, Southern Alaska, and Western Canada than in the analog winters. It was much drier in the West Coast and Southeast.


How was the upper level atmosphere like? For the most part it came close. The North Atlantic Oscillation (NAO) was positive as there is a upper level high pressure over Greenland. There is also upper level ridging over Northwest Africa. On the other hand, there were strong upper level trough over Russia and Central Europe.

I think my winter forecast held up well. I would give myself a A- as there are rooms for improvements. I base analogs on Pacific Decadal Oscillation (PDO), Atlantic Multidecadal Oscillation (AMO), and El Nino Southern Oscillation (ENSO). The reason I use PDO and AMO is that they are long term and change about every decade or so. ENSO changes every year, so one year could be La Nina, while the other year is El Nino. El Nino and La Nina have an impact on winter weather.

1951-1952, 1963-1964, and 2001-2002 had cool PDO, warm AMO, and neutral ENSO, which 2013 had. As for spring analogs, I am going to use the same analog winters, which are 1952, 1964, and 2002.

2011 Hurricane Season So Far and Stats

We are now in October of the 2011 Atlantic Hurricane Season. So far we have 16 storms, 4 hurricanes, and 3 major hurricanes with an Accumulated Cyclone Energy (ACE) of 99. So, how is this season stacking up to be? Is it truly an active season? All statistical values are from 1870 to 2010.

16 Storms
Mean = 9
Std Dev = 4.02
Kurtosis = 2.88
S.E. Kurt = 0.41
Skewness = 1.14

We are way above average in number of storms. Anything above a standard deviation of 4 is extremely active.

4 Hurricanes
Mean = 5
Std Dev = 2.61
Kurtosis = 0.75
S.E. Kurt = 0.41
Skewness = 0.80

We are close to average in number of hurricanes. It is within average. Anything +/-3 is above or below average is unusually active or inactive.

3 Major Hurricanes
Mean = 2
Std Dev = 1.75
Kurtosis = 0.84
S.E. Kurt = 0.41
Skewness = 1.10

We have an average number of major hurricanes so far this season. Anything above standard deviation of 2 is active, which would be 4 or more major hurricanes.

ACE of 99
Mean = 91
Std Dev = 54.28
Kurtosis = 0.40
S.E. Kurt = 0.41
Skewness = 0.93

We are withing average of ACE for the 2011 season. Anything above standard deviation of 54 is hyperactive, which would be 145.

ACE/Storm of 6.2
Mean = 9.78
Std Dev = 4.22
Kurtosis = -0.18
S.E. Kurt = 0.41
Skewness = 0.58

The ACE/Storm is rather low, but within the average. Below average ACE/Storm would be below standard deviation of 4.22 or 5.56 or less ACE/Storm.

25% Became Hurricanes
Mean = 0.59 (59%)
Std Dev = 0.17
Kurtosis = 0.89
S.E. Kurt = 0.41
Skewness = -0.29

The percentage of storms that became hurricanes in the 2011 season is unusually low, at 25 percent. In a normal season, 59 percent of storms become hurricanes. Even if we subtract the standard deviation of 0.17 from the mean, it is 0.42 or 42 percent.

18.8% Became Major Hurricanes
Mean = 0.21 (21%)
Std Dev = 0.15
Kurtosis = -0.02
S.E. Kurt = 0.41
Skewness = 0.56

The percentage of major hurricanes is within average. An Atlantic season with 6 percent or less would be an outlier. The last season with such a low percentage was 1994. No major hurricanes formed in 1994 as it was a quiet year due to El Nino.

The last time we had a season with many storms in a short time was 2005, which is the most active season record. 2005 had 28 storms, 15 hurricanes, and 7 major hurricanes with an ACE of 248. 2005 is an outlier, except some things and I will show you that.

28 Storms

15 Hurricanes

7 Major Hurricanes

ACE of 248

ACE/Storm of 8.9
The ACE/Storm in 2005 is within the mean. The reason is many of those storms in 2005 formed close to land. The ACE/Storm of 2004 was 14.9 because only 15 storms formed that year and many formed in the open Atlantic, intense, and were long lived.

53.6% Became Hurricanes
The percentage of storms that became hurricanes in 2005 is also within in the mean. 15 hurricanes is an outlier in that regard, but when it comes to percentage, not so. Keep in mind that 28 storms formed in 2005 and that right there is an outlier.

18.8% Became Major Hurricanes
The percentage of storms becoming major hurricanes is also within the mean. 1999 had 12 storms and 5 became major hurricanes, which is 41 percent, which makes it more than 0.15 (15 percent) standard deviation above the mean.

Source of data.
NOAA HRD-How many tropical cyclones have there been each year in the Atlantic basin? What years were the greatest and fewest seen?

The Average Tropical Cyclone Eye Size, ROCI, and Ambient Pressure

Let’s start with the Atlantic Basin. This is from 1988-2010 Best Track for Atlantic Hurricane
1988-2010 Best Track for Atlantic Hurricane

Eye Size
23.1 Nautical Miles (nm)

20 nm

Standard Deviation

5 nm (I do not know what is up with this, but the Best Track lists Wilma’s eye as 5 nm, even though the actual size was 2 miles or 1.7 nm)
Wilma 10/19/2005 1200 UTC (Z)

90 nm
Ophelia 9/13/2005 0000Z

Ambient Pressure
1011.1 Millibars (mb)

1011 mb

Standard Deviation

988 mb
Earl 9/5/2010 0000Z

Isidore 9/28/1996 0600Z

Radius of the Outer Closed Isobar (ROCI)
186.4 nm

180 nm

Standard Deviation

30 nm
Iris 9/20/1989 0000Z

555 nm
Gilbert 9/12/1988 1200Z

Here is the East Pacific, which is off the West Coast of Mexico.
For the East Pacific.

From 2001-2010 Best Track for East Pacific Hurricane
2001-2010 Best Track for East Pacific Hurricane

Eye Size
16.7 nm

15 nm

Standard Deviation

5 nm (There are probably East Pacific Hurricanes with smaller eyes.)
Juliette 9/24/2001 0600Z

75 nm
Douglas 7/24/2002 0000Z

Ambient Pressure
1009.2 mb

1009 mb

Standard Deviation

1000 mb
Blanca 6/23/2003 0000Z

1017 mb
Fausto 9/3/2002 0000Z

166 nm

160 nm

Standard Deviation

10 nm
Blanca 6/23/2003 0000Z

340 nm
Jimena 8/31/2009 0000Z

Here is a graph for mean and median.



Based on the statistics, Atlantic storms are larger than East Pacific. No surprise that the Atlantic Basin is much larger than the East Pacific Basin because there is cooler water to the west towards Hawaii. However, in El Nino years, the waters of East Pacific is more favorable, which means tropical cyclones last longer and can even travel into the Central Pacific and West Pacific as it happened with Hurricane John in 1994. The East Pacific is one of the most active basins in the world.