April 2017 Hurricane Season Forecast

It is almost this time of year. Hurricane Season is coming as it starts on June 1, 2017. Last year was quite an active hurricane season with Matthew, Nicole and Otto. Tropical Storm Arlene formed in the Northeast Atlantic.

Colorado State University
11/4/2 ACE: 75

Joe Bastardi (Weather Bell)
10 to 12 Storms/4 to 6 Hurricanes/1 to 2 Major Hurricanes ACE: 75 to 95

Tropical Storm Risk
11/4/2 ACE: 67

Accuweather
10/5/3

The Weather Channel
12/6/2

The analog years I am using are in which previous winter is La Nina or Neutral and second year after El Nino. The forecast is uncertain is El Nino will develop later in 2017 despite the water showing warming in the Equatorial Pacific, especially off the coast of South America.

2017
2015-2016 El Nino
2016-2017 La Nina
2017/2017-2018 El Nino/Neutral?

Based on this, the analog years are 1901, 1913, 1972, 1989, 2004, 2006, and 2009. They happened two years after El Nino and came off of a La Nina. Of course, there are other factors in play besides El Nino. I look at Atlantic Multidecadal Oscillation (AMO), Pacific Decadal Oscillation (PDO), Northeast Pacific Warm Pool (NEPWP), Equatorial Indian Ocean (EIO), Tropical South Atlantic (TSAI), Southern Ocean/Roaring Forties, and Atlantic Main Development Region (MDR).

Analog Years For 2017 (TS/H/MH ACE ACE/Storm)
1901 13/6/0 99 7.6
1972 7/3/0 36 5.1
1989 11/7/2 135 12.3
2004 15/9/6 227 15.1
2006 10/5/2 79 7.9
2009 9/3/2 53 5.9

So, what affect did those analog seasons have?
1901
Tropical Storm #2 made landfall on Matagorda, Texas on July 10, 1901 with 50 mph winds. This comes 10 months after the devastating Galveston Hurricane on September 8-9, 1900, which claimed 12,000 lives.

Hurricane #4 is known as the 1901 Louisiana Hurricane. The hurricane formed southwest of Azores on August 2, 1901. It traversed the Atlantic before making landfall on Florida on August 11, 1901. It emerges into the Gulf of Mexico and intensifies into a Category 1 hurricane due to the Loop Current on August 12, 1901. The hurricane makes landfall on Buras, Louisiana as a Category 1 hurricane with 85 mph wind and that makes a second landfall on Ocean Springs, Mississippi on August 15, 1901. Buras reports 4 feet of water, while New Orleans sees the Mississippi River rise by 7 feet. Up to 15 people are known to have died and inflicted $1 million of damages.

1972
1972 was a largely quiet season, but will be most remembered for Hurricane Agnes. It was a hurricane of non-tropical origin that formed over Yucatan Peninsula, Mexico on June 14, 1972. The tropical depression exits Yucatan into the Yucatan Channel. Agnes brushes Western Cuba as it heads towards Gulf of Mexico. Agnes becomes a Category 1 hurricane with 85 mph winds on June 18, 1972 as it is moving northwards towards Florida. Agnes weakens slightly as it makes landfall on Cape San Blas, Florida as a Category 1 hurricane with 75 mph, but likely a tropical storm as there was no sustained hurricane force winds reported. Agnes produced 7 foot storm surge and heavy rain in Florida. There is also a tornado outbreak in Florida from Agnes, which claimed 7 lives. A total of 9 people died in Florida from Agnes. Agnes is responsible for the deadliest tornado outbreak from a tropical cyclone. Agnes continues to weaken as it moves further inland. Agnes goes over the Atlantic on June 22, 1972 as a tropical storm, which developed over North Carolina. Agnes intensifies into a 70 mph tropical storm and makes landfall in Suffolk County east of New York City on June 22, 1972 with 65 mph winds. Once inland, Agnes becomes an extratropical storm. From there, Agnes starts dumping heavy rain throughout a large area of the Northeast from June 23 to 25, 1972. Many areas see 10 to 15 inches of rain including 19 inches of rain in Pennsylvia. Some areas likely saw higher amounts of rain. Pennsylvania took the brunt of Agnes from the heavy rain and massive flooding. Many other states were hit hard from Virginia, Maryland, New York, Ohio, and West Virginia. At least 119 people died in America from flooding, including 50 in Pennsylvania. On top of it, Agnes did $2.1 billion in damages, the most at the time. Agnes was not a major hurricane and will be remembered as an epic flood event in the Northeast, particularly in Pennsylvania.

1989
Before 2001 Tropical Storm Allison, there was 1989 Tropical Storm Allison, which formed from remnant of East Pacific Hurricane Cosme. Cosme made landfall east of Acapulco as a Category 1 hurricane with 85 mph winds. Allison paid a visit to the Upper Texas Coast on June 27, 1989 with 50 mph wind. Many areas in Texas saw 10 to 20 inches of rain. Like 2001 Allison, 1989 Allison loops over Texas, which dumps heavy rain over Northern and Central Louisiana. Many areas saw 15 to 20 inches including 30 inches at Winnfield, Louisiana. Eleven people lost their life in Texas Louisiana, and Mississippi.

Hurricane Chantal is the first hurricane to strike the Upper Texas Coast in 1989. Chantal is a small hurricane that made landfall on High Island, Texas on August 1, 1989 as a Category 1 hurricane with 80 mph winds and central pressure of 984 millibars. The highest winds is 70 mph with gusts as high as 105 mph. Many areas see 50 to 65 mph winds. Chantal produced three feet storm surge at Galveston. An area from Southern Harris County, Fort Bend, and Galveston County saw 8 to 12 inches of rain with amounts as high as 20 inches in Friendswood. One interesting aspect is that the “dirty” side of Chantal was on the southwest side of the hurricane, which produced most of the heavy rain. Thirteen people die, including 11 offshore.

Hurricane Hugo is the most intense hurricane of 1989, which peaked at 160 mph and central pressure of 918 millibars. Hugo was a Cape Verde storm as it formed from a tropical wave that came off of West Africa on September 9, 1989. Hugo became a tropical depression once the tropical wave left Africa. Hugo undergoes rapid intensification over the Atlantic. Hugo first encounter with land as it crosses between Guadeloupe and Montserrat on September 17, 1989 as a Category 4 hurricane with 140 mph winds. Gusts are as high as 210 mph! Guadeloupe is ravaged by strong winds and 8 feet storm surge as many homes are destroyed on top of 10 lives lost. A gust of 184 mph is recorded from a French research ship. Montserrat is ravaged by 20 feet storm surge as almost every house is damaged! Almost everyone are left homeless as a result. 21 people die in Montserrat. Hugo than makes its first landfall on St. Croix. A slowing Hugo puts St. Croix under prolonged hurricane force winds as high wave pelt the island. 90 percent of buildings are leveled and the infrastructure is destroyed by Hugo. The damage is a staggering $1 billion for St. Croix. Later that day, Hugo makes landfall on Vieques and Fajardo, Puerto Rico as a Category 3 hurricane with 120 mph winds. The highest sustained winds are 102 mph with gusts as high as 153 mph. Hugo ravages eastern Puerto Rico and decimates the crops. Hugo goes northward as a Category 2 hurricane. Hugo undergoes intensification to a Category 4 hurricane with 140 mph and central pressure of 944 millibars. Hugo is heading towards America. On the night of September 21, 1989, Hugo makes landfall as a Category 4 hurricane with 140 mph and central pressure of 934 millibars. The highest wind is 119 mph with gusts of 179 mph! Many areas see 80 to 120 mph winds with gusts of 120 to 180 mph. Hugo produces monster storm surge in the Charleston area due to its large size. Twenty feet storm surge are reported as it floods the coastal area. The fast motion of Hugo does not lead to massive flooding. 35 people lost their life in America and costliest hurricane at the time prior to Andrew in 1992.

Hurricane Jerry is the second hurricane to hit the Upper Texas Coast in 1989. It formed in the Bay of Campeche on October 12, 1989. Jerry became a Category 1 hurricane on October 15, 1989. As Jerry approaches the Upper Texas Coast, it continues to intensify. By the time it is getting closer to the Upper Texas Coast on October 16, 1989, it has 85 mph winds. Later that day, Jerry makes landfall on Jamaica Beach. Galveston sees 75 mph winds with gusts as high as 100 mph. The storm surge destroys a section of State Highway 87. Houston does not feel much impact from Jerry due to it small size. Many areas saw 2 to 4 inches with highest amount of over 6 inches in Silsbee. Three people died from Jerry all in Galveston as they were driving on the Galveston Sea Wall.

2004
Hurricane Charley is first of the four hurricanes to ravage Florida in the 2004 season. Charley formed over Barbados on August 9, 2004. Two days later, Charley becomes a hurricane south of Jamaica. As Charley heads towards Cayman, intensifies into a Category 2 hurricane and continues to intensify into Category 3 as it heads closer to Cuba. Charley makes landfall close to Punta Cayamas with 120 mph. The highest winds is 120 mph with gusts of 180 mph over Cuba. Over 13 feet storm is measured in Cuba. Charley continues traverses over Cuba and is west of Havana. Charley emerges from Cuba as a Category 2 hurricane with 110 mph and its first landfall on Florida is Dry Tortuga. A cold front is steering Charley towards Southwest Florida. Forecast models have Charley hitting Tampa Bay as a Category 3 hurricane. As it gets closer to the mainland, Charley undergoes rapid intensification into a Category 4 hurricane with 150 mph winds and 941 millibars. Charley first struck Cayo Costa and than Punta Gorda as a Category 4 hurricane. Charley produce up to 13 feet storm surge in Florida. The highest sustain winds is 128 mph with gusts of 192 mph! The highest measure gust is 172 mph out of Charlotte Regional Medical Center which was before anemometer failed. Charley travels along Interstate 4 and ravages Orlando as a Category 1 hurricane. Many areas see 5 to 8 inches of rain from Charley. Charley emerges into the Atlantic as a Category 1 hurricane. Than it makes landfall Cape Romain and North Myrtle Beach as a Category 1 hurricane. The highest wind is 63 mph with gusts of 96 mph. Charley is the first hurricane to hit South Carolina since Hugo in 1989. Charley dumps 3 to 7 inches of rain and produces 4 to 6 feet storm surge. Once Charley is gone, it claims 15 lives, mostly in Florida. There are 20 indirect deaths, which brings total to 35. Charley also does $16.3 billion in damages.

As Florida is recovering from Hurricane Charley, another storm forms off the Cape Verde Islands, Frances. Frances forms off the Cape Verde on August 24, 2004 and becomes a tropical storm the next day. Frances gains intensity is it traverses over the Atlantic, it undergoes rapid intensification and becomes a hurricane on August 26. Frances intensifies into a Category 4 hurricane with 135 mph winds. Frances undergoes eyewall replacement cycle, causing it to weaken to Category 3 hurricane. AS Frances travels westward and intensifies into a Category 4 with 145 mph winds on September 2, 2004 as it begins to ravage Bahama. Frances weakens into a Category 3 hurricane due to wind shear as it is over Bahamas. Frances maintains Category 2 hurricane with 105 mph as it gets closer to Florida. Frances is a large hurricane with a large eye. To make matters worse, France is moving slowly as it gets closer to Florida. Frances makes landfall on Hutchinson Island, Florida as a Category 2 hurricane with 105 mph winds on September 5, 2004. Frances ravages Florida with strong winds and heavy rain. Many areas in Florida see 10 to 20 inches of rain, which leads to flooding. As Frances is leaving Florida, it emerges into the Gulf of Mexico and make landfall on Aucilla River, Florida as a tropical storm. As Frances weakens, it becomes a huge rainmaker for the Southeast. The Appalachian Mountains draw more moisture out of the storm leading the heavy rain. Many areas in North Carolina see over 20 inches of rain including nearly 24 inches of rain in Mount Mitchell. The flooding causes Asheville to have no water for several days. There are 7 people killed and 43 indirect deaths, which brings the total of 50.

If things got worse, it does, as a tropical wave emerges from Africa on August 31, 2004, which becomes a tropical depression on September 2, 2004. The next day it is Tropical Storm Ivan. Ivan is a tropical storm for two days and on September 5, 2004, it becomes a hurricane and rapidly intensifies into a Category 3 hurricane with 125 mph winds. Ivan first hits Granada as a Category 3 hurricane. Many areas see 80 to 100 mph winds with gusts of 120 to 150 mph. Ivan unleashes devastating winds and destroys numerous buildings including a prison, which allows prisoners to escape causing more trouble. Most of the island is leveled by Ivan as it claims 39 lives. Ivan enters the Caribbean and rapidly intensifies into a Category 5 hurricane with 160 mph. Ivan comes approaches Jamaica on September 11, 2004 and pelts the nation with hurricane force wind and heavy rain. 17,000 people are left homeless from flooding and strong winds of Ivan. Ivan dumped heavy rain on Jamaica as much as 28 inches of rain! It is very likely the amount are higher. 17 people died in Jamaica. As Ivan moves away from Jamaica, it re-intensifies into a Category 5 hurricane. As Ivan comes closer to Grand Cayman, Ivan peaks at 165 mph and central pressure of 910 millibars. Ivan is the tenth most intense hurricane on record in the Atlantic as of 2017. The strong winds of Ivan damage many buildings despite strict building codes. Grand Cayman has winds of 157 mph with gusts as high as 236 mph! Ivan goes between Yucatan Peninsula and Cuba as a Category 5 hurricane. Cuba is being ravaged by full force Category 5 winds and heavy rain. Despite it, there are no reports of casualties in Cuba from Ivan. Ivan enters the Gulf of Mexico as a Category 4 hurricane and maintains it. As Ivan inches closer to the Gulf Coast, people are order to evacuate. The Superdome in New Orleans becomes a “shelter of last resort”, which had been used with Hurricane Georges in 1998. Many evacuate New Orleans as it most of the city is below sea level and would be very vulnerable to storm surge. However, Ivan goes east of New Orleans and makes landfall on Gulf Shore, Alabama as a Category 3 hurricane with 120 mph winds in the small hours of September 16, 2004. Alabama and Florida are hammered by strong winds of 80 to 100 mph with gusts of 120 to 150 mph on top of 15 foot storm surge. Ivan spawned numerous tornadoes, a total of 117, which is the most from a hurricane. On top of it, there is heavy rain of 10 to 15 inches as causes widespread flooding. Ivan moves further inland and weakens into a tropical storm. Appalachian Mountains are getting more heavy rain as it has been flooded by Hurricane Frances several weeks earlier. Part of Ivan break away and moves eastward back into the Atlantic and loops towards Florida. That piece of Ivan enters the Gulf of Mexico and begins to reorganize. By the time it is near Texas/Louisiana, Ivan becomes a tropical depression and tropical storm on September 22, 2004. Ivan makes landfall on Holly Beach, Louisiana as a tropical depression. Some areas in Louisiana and Texas had up to 8 inches of rain. Ivan claimed 92 lives and including 32 indirect deaths, which brings the total to 124 lives.

As Ivan is entering the Gulf of Mexico, a tropical depression develops east of Guadaloupe on September 13, 2004, which made landfall on the island nation. Many areas in Guadaloupe see 8 to 12 inches of rain. The next day it becomes Tropical Storm Jeanne as moves westward towards the Virgin Islands. On September 15, 2004, Jeanne makes landfall on Yabucoa, Puerto Rico as a tropical storm and travels over the island. Many areas see 5 to 10 inches of rain with the highest amount of nearly 24 inches in Vieques. Eight people have died from Jeanne in Puerto Rico. Jeanne exits Puerto Rico and becomes a Category 1 hurricane with 85 mph winds before it makes landfall on the eastern tip of Dominican Republic September 16, 2004. Jeanne traverses on the north side of Hispanola and weakening due to interaction with the mountains. Despite weakening, Jeanne is dumping heavy rain over Haiti and Dominican Republic for 30 hours. The prolonged heavy rain triggers widespread flooding and deadly mudslide in Haiti and Dominican Republic. The highest reported total is 13 inches with totals possibly going as much as 40 inches of rain in the mountains. The coastal city of Gonaives is hardest hit by flooding from Jeanne. At least 2,900 people are known to have died in the city. Throughout Haiti, at least 3,000 people have died from Jeanne. In Dominican Republic, 18 people have died from Jeanne from deadly flooding. Jeanne is now a tropical depression as it exits Hispanola on September 17, 2004. Jeanne lingers east of Bahamas and becomes a Category 1 hurricane with 85 mph winds on September 20, 2004. Jeanne loops around the Atlantic as a hurricane and moves westward towards the Bahamas. Jeanne continues to intensify into a Category 3 hurricane with 115 mph as it hits Abaco Island, Bahamas on September 25, 2004. Jeanne continues westward towards hurricane ravaged Florida. On the night of September 25, 2004, Jeanne makes landfall just two miles away from where Frances made landfall on Hutchinson Island as a Category 3 hurricane with 120 mph winds and 950 millibars, which is the peak of Jeanne. Jeanne produces 6 foot storm surge in Florida. Many areas see 60 to 90 mph winds with gusts of 90 to 135 mph. Many areas see 5 to 8 inches of rain with totals as high as nearly 13 inches of rain. Jeanne weakens as it is over Florida and moves northward dumping heavy rain throughout the Southeast and Mid-Atlantic region. It is unclear how much of the damage is from Charley, Frances or Jeanne. Regardless, Jeanne did a total of $7.66 billion in damages. Jeanne claims over 3,000 lives and exceeds Katrina and Stan in 2005. Jeanne is the deadliest hurricane of the 2000s.

2006
Tropical Storm Alberto formed between Cuba and Yucatan Peninsula, Mexico. The storm peaks at 70 mph west of Tampa Bay on June 12, 2006 over the Loop Current. Alberto makes landfall on Taylor County, Florida on June 13, 2006 with 45 mph winds. Many areas in the Southeastern US see 3 to 7 inches of rain, which leads to flooding. Grand Cayman records up 22.72 inches of rain in 24 hours. Many areas in Cuba see 7 to 12 inches of rain, including 17.52 inches in Pinar del Rio province, Cuba. Two people died in Florida, and one died in North Carolina. Four sailors off the coast of Newfoundland Canada went missing when Alberto is an extratropical storm.

Hurricane Ernesto formed west of Grenada on August 24, 2006. It becomes a hurricane southwest of Haiti on August 27, 2006 with 75 mph winds. Ernesto weakens as it interacts with the mountains of Haiti and Dominican Republic. Ernesto brushes the western tip of Haiti on August 28, 2006 as a weak tropical storm with 45 mph winds. Than Ernesto makes landfall near Guantánamo Bay, Cuba. Ernesto continues northwestward towards Cuba, first hitting Plantation Key, Florida, and than Miami-Dade County as a tropical storm. Ernesto traverses over Florida be emerging over the Atlantic, which intensifies to 70 mph and possibly a Category 1 hurricane. Ernesto makes landfall on Oak Island, North Carolina on August 31, 2006. Haiti sees up to 11 inches of rain and strong winds. Cuba sees rain amounts of 2 to 5 inches of rain with highest of 7.46 inches in Nuevitas, Camagüey. Florida sees 3 to 6 inches of rain with highest of 8.72 inches at South Golden Gate, Florida. The Carolina sees 4 to 8 inches of rain with 14.61 inches being the highest at Wrightsville Beach, North Carolina. Five people died in Haiti, while two died in Virginia when Ernesto is extratropical storm.

2009
Hurricane Bill is the most intense hurricane for 2009 as it was a Category 4 hurricane with 130 mph winds and central pressure of 943 millibars. On August 22-23, 2009, the outerbands of Bill affect the Eastern Seaboard, particularly Massachusetts. Bill dumps heavy rain and produces numerous high waves on the East Coast. Hurricane Bill makes landfall on Point Rosie, Newfoundland as a 70 mph tropical storm. Many areas in Newfoundland and Canadian Maritime provinces experience strong winds and heavy rain. The coastal areas are pelted by high waves that a buoy recorded 87 feet waves!

Hurricane Ida was a Category 2 hurricane with 105 mph winds and central pressure of 975 millibars. However, it is better remembered as a powerful Nor’easter dubbed Nor’Ida. The storm would hammer the East Coast from November 11 to 17, 2009 with heavy rain and strong winds. The highest rainfall total is 18 inches of rain in Virginia. The storm also produce over 7 foot storm surge, which is on par with Hurricane Isabel in 2003.

Some of the analog seasons are inactive like 1972, but are very memorable. It shows it only takes just one to make a huge difference. Some are very active and deadly like 1989 and 2004. There were also Category 5 hurricanes in 1989 and 2004.

Here is a heat map of analog seasons. It is based on 300 mile radius from the storms.

The high risk areas are Cuba, Yucatan Peninsula, Florida Panhandle, South Florda, Carolinas, Bahamas, and Upper Texas Coast. However, when you look at the whole basin, everyone is at risk for landfall, which is why I never make landfall predictions. Everyone is at equal risk as I always say!

Analog
Mean
10.83/5.5/2.00
11/6/2 (Rounded Up)

Median
10.50/5.50/2.00
11/6/2 (Rounded Up)

Standard Deviation
2.86/2.35/2.19

ACE
Mean
104.83

Median
89

Standard Deviation
69.23

ACE/Storm
Mean
8.99

Median
7.76

Standard Deviation
3.90

How do analog seasons compare as a whole. Statistics from 1870 to 2016.

Mean
9.86/5.50/2.04
10/6/2

Median
9/5/2

Standard Deviation
4.21/2.61/1.66

ACE
Mean
92.18

Median
83

Standard Deviation
53.73

ACE/Storm
Mean
9.38

Median
8.67

Standard Deviation
4.04

The analog seasons are within standard deviation, which indicates this upcoming hurricane season is going to be within average.

What is my prediction for this season?
6 to 12 named storms, likely 10 named storms
3 to 8 hurricanes, likely 6 hurricanes
1 to 3 major hurricanes with 2 major hurricanes
ACE is 65 to 110 with ACE likely of 70 to 100

This excludes Arlene, which formed earlier in April, which would be 11 named storms. I do not think this season will be as active as last year. Of course, it only takes one to be bad like in 1972 with Agnes.

Let’s see how my April 2016 hurricane forecast compare to the actual 2016 season.

7 to 13 named storms, likely 11 named storms
4 to 8 hurricanes, likely 6 hurricanes
2 to 4 major hurricanes with 3 major hurricanes
ACE is 90 to 150 with ACE likely of 100 to 130

2016 Actual Number
15 Named Storms
7 Hurricanes
4 Major Hurricanes
141 ACE

I was off with named storms. I was close with hurricanes, major hurricanes, and ACE. There is always room for improvement either way.

Regardless of forecast, I think 2017 could be an interesting hurricane season. It is the same Atlantic name list used in the devastating 2005 season, which produced Dennis, Emily, Katrina, Rita, and Wilma. Of course some of the names are not there with the exception of Emily.

2016 And 2017 Atlantic Hurricane Season Forecast

Christmas is sure looming, but the 2016 Atlantic Hurricane Season is not too far away, six months from now. I am going to also look at 2017 Hurricane Season, which would be second year following the strong El Nino of 2015-2016. That is eighteen months from now at the writing of this article.

Analog Years For 2016 (TS/H/MH ACE ACE/Storm)
1878 12/10/2 181 15.1
1889 9/6/0 104 11.6
1897 6/3/0 55 9.2
1942 11/4/1 63 5.7
1958 10/7/5 121 12.1
1998 14/10/3 182 13.0

Here is the overall Atlantic Hurricane Season Statistics

1870-2015 Atlantic Hurricane
Mean
9.82/5.49/2.03
10/5/2 (Round Up

Median
9/5/2

Standard Deviation
4.20/2.62/1.66

ACE
Mean
91.82

Median
83.00

Standard Deviation
53.77

ACE/Storm
Mean
9.38

Median
8.70

Standard Deviation
4.06

I came up with the analog for 2016, since we are in El Nino and once El Nino fades, La Nina comes and it can get strong. It is based on past El Nino and warm Atlantic Multidecadal Oscillation (AMO). Here is the statistics for 2016 Analog Season.

2016
Mean
10.33/6.67/1.83
11/7/2 (Round Up)

Median
10.50/6.50/1.50
11/7/2 (Round Up)

Standard Deviation
2.73/2.94/1.94

ACE
Mean
117.67

Median
112.50

Standard Deviation
55.25

ACE/Storm
Mean
11.12

Median
11.85

Standard Deviation
3.28

Looking at it, it is above average ranging from number of storms and hurricanes. Major hurricanes is about the same. However, keep in mind, anything before satellite should taken with a grain of salt. Seasons prior to satellite would of likely had more storms than recorded, but they could be in the middle of the Atlantic or some short lived tropical storm. Seasons like 1889 and 1897 likely had major hurricanes.

So, what is my prediction for the 2016 Atlantic Hurricane Season
10 to 16 named storms, likely 14 named storms
6 to 10 hurricanes, likely 8 hurricanes
2 to 5 major hurricanes with 3 major hurricanes
ACE is 110 to 190 with ACE likely of 130 to 160

Looks to be an active 2016 Atlantic Hurricane Season.

Here is a GIS heat map I created for 2016 analog seasons. It is within 300 miles.

2016DecemberAnalogHurricaneHeatMap

Looking at the heat map, there are areas most at risk. Off the Eastern Seaboard with North Carolina most at risk. Haiti and Dominican Republic, Caribbean and Cuba, Southwest Florida, and Gulf of Mexico. Anywhere is at risk, but those areas especially are the ones to keep an eye on. Let’s see what 2017 Atlantic Hurricane Season forecast.

Analog Years For 2017 (TS/H/MH ACE ACE/Storm)
1879 8/6/2 64 8.0
1890 4/2/1 33 8.3
1898 11/5/1 113 10.3
1943 10/5/2 94 9.4
1959 11/7/2 77 7.0
1999 12/8/5 177 14.8

I came up with the analog for 2017, based on the second year following El Nino. Warm AMO is taken into account. Here is the statistics for 2017 Analog Season.

2017
Mean
9.33/5.50/2.17
10/6/2 (Round Up)

Median
10.50/5.50/2.00
11/6/2 (Round Up)

Standard Deviation
2.94/2.07/1.47

ACE
Mean
93

Median
85.50

Standard Deviation
49.30

ACE/Storm
Mean
9.63

Median
8.85

Standard Deviation
2.78

Looking at it, 2017 is closer to average than 2016. Interestingly, there are more major hurricanes on average than compared to 2016 analog seasons. Still, looking at the actual analog seasons, it is generally less active. Again, keep in mind, anything before satellite should be taken with a grain of salt. There were likely more storms before satellite era that went undetected.

So, what is my prediction for the 2017 Atlantic Hurricane Season
9 to 14 named storms, likely 12 named storms
4 to 9 hurricanes, likely 7 hurricanes
2 to 4 major hurricanes with 3 major hurricanes
ACE is 100 to 180 with ACE likely of 120 to 150

Here is a GIS heat map I created for 2017 analog seasons. It is within 300 miles.

2017DecemberAnalogHurricaneHeatMap

Looking at the hot spots, West Indies, Lesser Antilles, Caribbean and Cuba, Off the Eastern Seaboard, Bahamas, and Western Gulf of Mexico with Texas and Louisiana at most risk. Again, anywhere is at risk, but those areas especially are the ones to keep an eye on.

The 2016 and 2017 Atlantic Hurricane Forecast is all preliminary at this time. It is subject to change. I should have a better idea about the 2016 Atlantic Hurricane Season in April 2016 and for 2017, April 2017. That would be sixteen months from now of course. This is just a thought because of the strong El Nino we have and what impact a strong El Nino has on the Atlantic. By Summer 2016, it could be still El Nino. It could also be Neutral or La Nina by than. Until than, please check back in April 2016 for the 2016 Atlantic Hurricane Season forecast.

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
Outlier

15 Hurricanes
Outlier

7 Major Hurricanes
Outlier

ACE of 248
Outlier

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?

Why Texas Is So Dry Part 2

It has been really dry lately in Texas. The reason it is dry is that we are in La Nina, which pushes the jet stream further north than usual. It causes storm systems to go further north, which means it allows warm air aloft above the surface to develop unchecked. The warm air aloft is from the deserts of Mexico. The warm air aloft is always there, but it is kept in check by storms systems that destroys them. Another reason why Texas is so dry is the upper level is drier than normal. It could be really humid on the ground, but go 5,000 feet (1,524 meters), it is much drier. The dry upper atmosphere is again from the dry and warm air of Mexican deserts. In wet years, the upper part of the atmosphere is wetter than normal. I am going to be comparing two springs from March to May. The wettest spring on record for Upper Texas Coast is 1997 and current spring, which is likely going to be one of the driest spring on record.

Spring 1997 Relative Humidity Anomaly

Spring 2011 Relative Humidity Anomaly

Notice anything? Spring 1997 was unusually humid at the surface and at the 5,000 feet (1,524 meters or 850 millibar) level. Spring 2011 humidity level is within average. However, at 5,000 feet, it is dry. The surface can be very humid, but when you go 5,000 feet (1,524 meters), it is much drier. The low relative humidity at the upper levels inhibit storms from forming. The low moisture level is what kills storms from forming over eastern part of Texas.

If you think Texas is in a drought and abnormally warm, we are not alone. Europe is also in midst of a severe drought and abnormal warmth for the same reason Texas is in, La Nina. Texas and Europe’s drought are one of the worst on record.

Spring 2011 Relative Humidity Anomaly In Europe

The level of moisture at the surface and 5,000 feet (1,524 meters) is abnormally dry.

Spring 2011 Air Temperature Anomaly In Europe

Europe is abnormally warm at the surface and 5,000 feet (1,524 meters).

Spring 2011 Geopotential Height Anomaly In Europe

There is a blocking feature over Europe at the 18,000 feet (5,487 meters). That upper level high pressure is blocking any storm systems that give Europe rain.

The same atmospheric setup in Europe is very similar to in Texas, low moisture, warmer temperature, and upper level block pattern.

October To April Rainfall

This past October to April has been very dry, easily one the driest on record. The culprit is La Nina, which causes the jet stream to go further north, carrying storms further away. I did a correlation between October to April rainfall total and May rainfall total and only April and May rainfall totals in the Upper Texas Coast. It is from the NOAA Divisional Data.

Two-tailed p value: 0.198
Pearson’s R statistic: 0.121
Degrees of Freedom (df): 113

Based on analysis, there is a positive correlation for October to April rainfall total and May rainfall total. It is not significant since the p-value is above 0.05.

Two-tailed p value: 0.443
Pearson’s R statistic: 0.072
Degrees of Freedom (df): 113

April and May rainfall total does not correlate much at all. It could go either way, a dry or wet April may give way to a dry or wet May. Since the p-value is above 0.05, it is not significant.

What is the verdict? October to April and only April rainfall does not predict how May rainfall will be like. So, there could be a chance that May could be either be wet or dry.