April 2018 Hurricane Season Forecast

Many areas are still reeling from Harvey, Irma, and Maria. Many people lost their properties and are rebuilding. Some lost their life. Hurricane Season is coming as it starts on June 1, 2018.

Colorado State University
14/7/3 ACE: 130

Joe Bastardi (Weather Bell)
11 to 15 Storms/5 to 7 Hurricanes/1 to 3 Major Hurricanes ACE: 90 to 110

Tropical Storm Risk
12/6/2 ACE: 84

Accuweather
12 to 15 Storms/6 to 8 Hurricanes/3 to 5 Major Hurricanes

The Weather Channel
13/7/2

The analog years I am using are in which previous winter is a weak to moderate La Nina. The forecast is uncertain with El Nino or Neutral.

Based on this, the analog years are 1891, 1945, 1963, 1989, 1996, 2001, 2006, and 2012. They are coming 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, Atlantic Main Development Region (MDR), and Indian Ocean Dipole (IOD). The IOD is based on Australian Bureau of Meteorology forecast.

Analog Years For 2018 (TS/H/MH ACE ACE/Storm)
1891 10/7/1 116 11.6
1945 11/5/2 63 5.7
1963 9/7/2 118 13.1
1989 11/7/2 135 12.3
1996 13/9/6 166 12.8
2001 15/9/4 110 7.3
2006 10/5/2 79 7.9
2012 19/10/2 129 6.8

What affect did those analog seasons have? Let’s start with 1891. Hurricane #1 hit Galveston after intensifying into Category 2 hurricane with 100 mph winds on July 6, 1891. Galveston was flooded from storm surge. It spawned tornadoes in Baton Rouge, which hit a prison, killing 10 people. There is also Hurricane #3 better known as as the Martinique Hurricane was the only major hurricane for the 1891 season. It intensified into a Category 3 hurricane later that day and hit Martinique. There were reports of lightning, which suggests the hurricane was intensifying. Martinique was leveled by strong winds and power waves. Once the hurricane passed, at least 700 people died from the hurricane. Some put the death toll as high as 1,000. The hurricane traverses and makes landfall on Dominican Republic as a Category 2 hurricane. Than it goes northward towards Grand Turk of the Turks and Caicos Islands. The hurricane goes over Bahamas and makes landfall on South Florida as a Category 1 hurricane.

1945 had two major hurricanes hit the US. There is Hurricane #5 or 1945 Texas Hurricane. It made landfall as a Category 3 hurricane over Port Aransas on August 27, 1945. It was a slow moving hurricane as it moved slowly across Texas pelting with strong winds, storm surge, and heavy rain. Some areas saw storm surge as high as 15 feet. The moisture swath could be felt as far as Tampa Bay. The slow movement caused rainfall amounts of 20 inches with amounts likely over 30 inches. The hurricane claimed 3 lives and caused $20 million in damages. Hurricane #9 or 1945 Homestead hurricane is the most intense hurricane to strike Florida since the 1935 Labor Day Hurricane. It was a rather small hurricane. It went over Bahamas and Grand Turk Island as it intensifies. It made landfall on Key Largo as a Category 4 hurricane with 130 mph winds. It emerges out of Florida and makes landfall between Georgia and South Carolina as a tropical storm with 70 mph winds. A total of 26 people died, including 22 in Bahamas and Grand Turk Island. Four died in the US.

1963 was a devastating season. Hurricane Cindy developed in the Gulf of Mexico. It made landfall as a Category 1 hurricane on High Island on September 17, 1963. It stalls over Southeast Texas and dumps heavy rain in amounts of of nearly 24 inches measured. It is certainly possible higher rainfall amounts fell in East Texas. Cindy claimed 3 lives. Hurricane Flora is a large Category 4 hurricane. It was a Cape Verde Hurricane. Once it approached Haiti, Dominican Republic, Jamaica, and Cuba, it stalls out. Flora dumps extremely heavy rain, especially in mountainous areas. In a six day period, some areas see over 100 inches of rain in Cuba, with likely higher amounts. Flora is the wettest known Atlantic tropical cyclone. 8,000 people died from massive flooding from Flora. Flora ranks as one of the deadliest Atlantic hurricanes besides 1780 Hurricane, 1900 Galveston, Mitch (1998), and Fifi (1974).

1989 was an active season. Tropical Storm Allison, which formed from remnant of East Pacific Hurricane Cosme. Allison paid a visit to the Upper Texas Coast on June 27, 1989 with 50 mph wind. Many areas saw 10 to 20 inches with the highest being 30 inches. Eleven people lost their life in Texas Louisiana, and Mississippi. Hurricane Chantal and made landfall on High Island, Texas on August 1, 1989 as a Category 1 hurricane. 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. 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 first ravages the Caribbean as a monster hurricane. It flattens almost every building in Guadeloupe, Montserrat, St. Croix, and Puerto Rico. Hugo makes landfall as a Category 4 hurricane. Hugo produces monster storm surge in the Charleston area due to its large size. 35 people lost their life in America. Hurricane Jerry is the second hurricane to hit the Upper Texas Coast in 1989. 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. Three people died from Jerry all in Galveston as they were driving on the Galveston Sea Wall.

1996 had many major hurricanes form, more so than 1995. Hurricane Bertha made landfall as a Category 2 hurricane on North Carolina on July 12, 1996. It peaked as a Category 3 hurricane near Puerto Rico. Bertha traversed across the Eastern Seaboard with heavy rain and strong winds. Bertha claimed 12 lives. Hurricane Cesar made landfall as a Category 1 hurricane on Bluefields, Nicaragua on July 27, 1996. It dumped heavy rain over Nicaragua, Costa Rica, and El Salvador. A total of 142 people, which includes 29 missing, mostly in Central America. Cesar crosses into the Pacific and becomes Douglas, which a rare crossover. Douglas is a power Category 4 hurricane. Hurricane Fran formed on August 23, 1996 as a Cape Verde Hurricane. It developed with Hurricane Edouard to the east. Fran becomes a Category 3 hurricane off the Bahamas and is a large hurricane. It made landfall on September 5, 1996 near Cape Fear, North Carolina as a Category 3 hurricane. Fran ravaged the Carolinas with strong winds, storm surge, and heavy rain. It moved northward towards Virginia as it is weakening. Fran becomes more of a rain event as winds are diminishing. Once Fran is gone, a total of 27 lives are lost. Hurricane Hortense formed on September 3, 1996. It was slow to develop and first strikes Guadeloupe as a tropical storm on September 8, 1996. It becomes a hurricane on September 9, 1996. Not too long after Hortense made landfall around Guánica, Puerto Rico as a Category 1 hurricane. It emerges and hits the eastern tip of Dominican Republic. As Hortense moves northward it becomes a Category 4 hurricane and makes its final landfall on West Quoddy, Nova Scotia as a Category 1 hurricane. Hortense dumped flooding rains in Puerto Rico. Hortense claimed a total of 39 lives. Hurricane Lili was a long lived hurricane that formed on October 14, 1996. It ravages Central America, Cuba, Bahamas, and United Kingdom. It made landfall on Matanzas Province, Cuba as a Category 2 hurricane on October 18, 1996. Than heads towards Bahamas where it goes over San Salvador Island and Great Exuma on October 19, 1996. Lili becomes a Category 3 hurricane. Than Lili hits United Kingdom as a strong extratropical storm. Once it is all over, 22 lives, mostly in Central America.

2001 started with Tropical Storm Allison. It made landfall on June 5, 2001 near Freeport, Texas. It lingered over Texas dumped heavy rain. On the early morning of June 7, 2001, heavy rain fell in Beaumon and Sugar Land, Texas. Up to 15 inches of rain fell along feeder band. Louisiana got heavy rain from the large circulation of Allison. Than on the evening of June 8, 2001, thunderstorms form near the center of Allison. Than they all converge over Houston dumping heavy rain for nearly 12 hours. Once it is all over, up to 28 inches fell! A total of 40 inches fell from June 5 to 10 near Beaumont, Texas. Thibodaux, Louisiana got nearly 30 inches of rain. The heavy rain led to severe flooding in Houston area, the worst prior to Harvey. Allison traversed across the Southeastern and Northeastern US dumping heavy rain. Hurricane Gabrielle formed on September 11, 2001, the day America was attacked in New York, Arlington, and Shanksville. It made landfall on September 14, 2001 near Venice, Florida as America was mourning the victims of horrifying terrorist attack. Hurricane Iris was a powerful October hurricane. Iris traveled the Caribbean and rapidly intensified into a Category 4 hurricane with 145 mph winds. On October 8, 2001, Iris makes landfall on Monkey River Town, Toledo, Belize. A 70 mile area is ravaged by strong winds and storm surge. The hurricane claimed 23 lives in Belize and 36 lives including Guatemala, Dominican Republic, and Mexico. Later in the month, Hurricane Michelle forms. Michelle formed near Nicaragua on October 29, 2001 and moved inland near Puerto Cabezas, Nicaragua. It lingered over Nicaragua and Honduras for more than a day dumping heavy rain. 98 people died in Nicaragua and Honduras from deadly flooding, which happened three years to the day Hurricane Mitch ravaged Central America with epic rainfall and flooding. Michelle exits Central America into the Caribbean. It undergoes rapid intensification into a Category 4 hurricane. Michelle makes landfall first on Cayo Largo del Sur, Cuba on November 4, 2001. It moves into Bay of Pigs. Cuba is ravaged by strong winds, waves, storm surge, and heavy rain. Five people died in Cuba from Michelle. Michelle moves northward towards Bahamas on November 5, 2001 and becomes an extratropical storm due to interaction with a cold front.

2006 was predicted to be just as active as 2005. Turned out to be an average season due to a developing El Nino and dry Saharan Desert air blowing over the Atlantic. Tropical Storm Alberto landfall on Florida on June 13, 2006 with 45 mph winds. Many areas in the Southeastern US, Grand Cayman, and Cuba have heavy rain. 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 makes landfall on Cuba. Ernesto and Florida. 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. Five people died in Haiti, while two died in Virginia when Ernesto is an extratropical storm.

2012 proved to be an active season. Hurricane Isaac was a large Category 1 hurricane that hit New Orleans area and Mississippi. It moved slowly as it dumped heavy rain and produced high storm surge. A large area saw at least 10 inches of rain. The hurricane tested the newly improved levee and flood control system that was ravaged by Katrina in 2005. Hurricane Sandy is the most intense hurricane of the 2012 Atlantic Hurricane season. It is best known as Superstorm Sandy, when it was a very large hurricane/extratropical storm hybrid as it had tropical storm force winds diameter of 1,150 miles! Before it became the superstorm, it hit near Kingston, Jamaica as a Category 2 hurricane on October 24, 2012 and Santiago de Cuba, Cuba as a Category 3 hurricane on October 25, 2012. As it went towards the Atlantic, Sandy got larger as it showed more of an extratropical storm like appearance with a warm core. Than Sandy made landfall as a large extratropical storm with Category 1 winds on Brigantine, New Jersey on October 29, 2012. Sandy set numerous records from lowest air pressure to high storm surge. Battery Park, New York had nearly 14 feet storm surge. Sandy is the most hurricane to make landfall northeast of Cape Hatteras, North Carolina. It also dumped heavy rain mainly over Maryland and Delaware of nearly 13 inches of rain. Sandy claimed a total of 233 lives and did $68.7 billion in damages. Sandy was the second costliest hurricane prior to Harvey and Maria.

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

The heat map has Upper Texas Coast, Southeast Georgia, Carolinas, and Windward Islands. However, when you look at the whole basin, everyone is at risk for landfall. I never make landfall predictions. Everyone is at equal risk for landfall.

Analog
Mean
12.25/7.38/2.63
12/7/3 (Rounded Up)

Median
11/7/2

Standard Deviation
3.33/1.85/1.60

ACE
Mean
114.50

Median
117

Standard Deviation
32.14

ACE/Storm
Mean
9.69

Median
9.75

Standard Deviation
3.03

How do analog seasons compare as a whole. Statistics from 1870 to 2017.

Mean
9.91/5.53/2.07
10/6/2

Median
9.5/5/2
10/5/2

Standard Deviation
4.24/2.63/1.69

ACE
Mean
93.09

Median
83.5

Standard Deviation
54.66

ACE/Storm
Mean
9.41

Median
8.68

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?
11 to 16 named storms, likely 13 named storms
4 to 10 hurricanes, likely 7 hurricanes
1 to 4 major hurricanes with 3 major hurricanes
ACE is 80 to 140 with ACE likely of 100 to 125

Let’s see how my April 2017 hurricane forecast compare to the actual 2017 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

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

2017 Actual Number
17 Named Storms
10 Hurricanes
6 Major Hurricanes
224 ACE

Many including myself severely underforecasted the 2017 season, which turned out to be active and brutal. The 2013 Atlantic Hurricane Season was overforecasted as it turned out to be a quiet season. There is always room for improvement.

Regardless of forecast, I think 2018 could be an interesting hurricane season. It is the same Atlantic name list used in the 2012 season, which produced Isaac and Sandy. Sandy is retired due to devastating effects on the Eastern Seaboard and Cuba.

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2017-2018 Winter Forecast

Winter has started and Christmas has passed. It is very cold throughout America. Last winter we had a borderline Neutral/La Nina. This time around, we have La Nina. Other factors to consider are Pacific Decadal Oscillation (PDO), Atlantic Multidecadal Oscillation (AMO), Northeast Pacific Warm Pool (NEPWP), Equatorial Indian Ocean (EIOI), Indian Ocean Dipole (IOD), Tropical South Atlantic (TSAI), Roaring Forties (R40I), Hudson and Baffin Bay (HBB), and Quasi-Biennial Oscillation (QBO). However, since this El Nino is large and strong and has significant impact, it will weigh in more than other factors listed. Here are the analog winters I came up with.

1881-1882
1928-1929
1933-1934
1937-1938
1944-1945
1949-1950
1961-1962
1984-1985
2000-2001

I chose these winters because the previous winter was La Nina or Neutral. Here is a table I created to identify strongest analogs.

Year AMO PDO NEPWP EIOI IOD TSAI R40I HBB QBO Total
1881-1882     1 1 1   1     4
1928-1929 1 1     1     1   4
1933-1934 1 1 1 3
1937-1938 1 1 2
1944-1945 1 1 1 1   1 1 1   7
1949-1950 1 1 1   1 1     1 6
1961-1962 1 1 1     1 1     5
1984-1985       1 1 1 1   1 5
2000-2001 1 1 1 1 1 1 1   1 8

I look at eight ocean and one upper wind patterns based on Fall (September to November) averages. The cutoff for further analysis is four (before 1948 due to QBO data not available). With QBO, the cutoff is five. We can eliminate these winters.
1933-1934
1937-1938

The analogs I will be looking at are:
1881-1882
1928-1929
1944-1945
1949-1950
1961-1962
1984-1985
2000-2001

Let’s start with the ever important temperature. All maps were generated with 20th Century Reanalysis Monthly Composites. They are all Northern Hemisphere.

Alaska, Bering Sea, Southern US, Eastern US, Eastern Canada, Greenland, and Western China are warmer than normal. Arctic, Siberia, Korea, Japan, Central Asia, Southeast Asia, Europe, North Africa, Western US, and Western Canada are cooler than normal. Southeast Texas is warmer. Keep in mind, some areas do not have weather records, so this may be spurious as it includes 1881-1882.

Wonder what winter will be like in the rain department?

It is drier in Western US, Western Canada, Southeast US, Cuba, Bahamas, Southern China, Central Asia, Western Europe, and Northern Europe. It is wetter in Central US, Caribbean, Alaska, Northern Japan, Southeast Asia, and North Africa. Southeast Texas sees average amount of rain in the winter. Again, this may be spurious as it includes 1881-1882.

Let’s look at the upper air pattern.

There is upper level ridging south of Alaska, which is negative East Pacific Oscillation (EPO), Eastern US, Siberia, Greenland, and Northeast Canada. Ridging over Greenland and Northeast Canada is negative North Atlantic Oscillation (NAO). There is troughing over Central Canada and one running from Japan, Korea, and to all of Central Asia. Negative NAO and EPO usually means cold air will go down south.

How were winters like in these analog years?

1881-1882
A warm winter dominated the US. Southeast Texas had a warm winter.

1928-1929
A cold blast came on the start of 1929 in Southeast Texas. Another hard freeze came in February 1929. It did not go above freezing on February 9, 1929 with high of 29°F.

1944-1945
A world engulfed in World War II. No freezes occurred in Southeast Texas.

1949-1950
Most of the US had a warm winter, including Southeast Texas.

1961-1962
Snow fell in Houston area in December 1961. January 1962 had a strong cold blast in America. A strong high pressure with pressure of 1062 millibars was recorded. Many areas saw record lows set. Houston saw a record low on January 10, 1962, which has been beaten in 1977.

1984-1985
Cold blasts occurred in January and February 1985. The 1985 Presidential Inauguration was the coldest on record. Many areas saw record lows set. Houston saw record lows on January 20-21, 1985. Near records occurred on February 1-2, 1985. Snow fell in Houston in January and February 1985. San Antonio saw record snowfall on January 11-13, 1985.

2000-2001
Eastern US had a cooler than normal winter. Southeast Texas had a cold winter.

I am not suggesting we will see a cold blast on par with February 1929, January 1962, January 1985, and February 1985. It is possible this winter could see more cold blasts.

I think this winter could be a cooler winter despite what the past analog winters being warm. I would not be surprised to hear of a major cold blast this coming winter or snow falls again.

A New Normal Part 2

We are living in a new world and reality, a post-Harvey Texas. Just a week ago, a Category 4 monster, Hurricane Harvey was barreling down towards Rockport. Harvey was the first major hurricane to make landfall on America since Wilma in 2005. I think the National Hurricane Center (NHC) may increase Harvey’s peak to 140 mph 224 km/h 122 knots hurricane. Harvey being the first major hurricane to make landfall since Wilma has been largely overshadowed by the epic flooding that ravaged Houston and Beaumont area. That started on the night of August 26, 2017. A series of core rains that form near the center of Harvey.

One good news, the area of thunderstorms in the Southwest Gulf of Mexico does not pose a threat due to wind shear. It is an area of thunderstorms from a tropical wave. However, a cold front that is passing to Southeast Texas could set off thunderstorms and more rain as it picks up moisture from the tropical wave per NWS Houston.

000
FXUS64 KHGX 020220
AFDHGX

Area Forecast Discussion
National Weather Service Houston/Galveston TX
920 PM CDT Fri Sep 1 2017

.UPDATE...
Forecast for tonight looking on track. Updated temps and
dewpoints for trends.

Beat

&&

.PREV DISCUSSION... /ISSUED 628 PM CDT Fri Sep 1 2017/

AVIATION...
Sea breeze and outflow boundary are working their way inland with not
a whole lot of wind changes. SHRA activity that did develop late this
afternoon has now moved away from LBX. Look for light and variable
winds overnight with some patchy MVFR fog possible again at CXO. Expect
VFR conditions tomorrow with mainly light and variable winds. 42

PREV DISCUSSION... /ISSUED 343 PM CDT Fri Sep 1 2017/

DISCUSSION...
Current satellite is showing the typical afternoon cumulus field
developing across southeast Texas. There is a little enhanced
cumulus along the coast but the weak seabreeze is having trouble
generating enough lift for anything more than very isolated and
weak showers. This is expected again tomorrow and the dry weather
is greatly appreciated.

Models are still showing an upper level trough dropping into North
Texas tomorrow night though a significant change is a stronger
ridge over the southern Plains pinching the trough off from the
westerly flow and retrograding it back to the southwest earlier
than previous model runs. A more westerly position of this trough
means weaker lift and lower PoPs for Saturday night and Sunday.

Tropical moisture in the southern Gulf of Mexico will move north
early next week giving us our next decent chance for rainfall. At
the same time, a western U.S. ridge will amplify and northerly
upper flow will drive a cold front through the area Tuesday night
and early Wednesday. The tropical moisture already in place will
interact with this cold front producing a line of showers and
storms along the front. Fortunately the cold front will be moving
fairly quickly, especially for this time of year, pushing the rain
south by Wednesday afternoon. Behind the front, cool and dry air
will filter into the area bringing very pleasant temperatures with
highs only in the lower 80s Wed/Thu.

Hennig

There is also a tropical wave in the far eastern Atlantic that has a good chance of becoming Jose in the next five days. My main concern is Hurricane Irma, which is a Category 3 hurricane out in the Atlantic. Many are wondering where will Irma go. The latest heat map from various forecast models and GFS ensemble track guidance. The GFS goes up to 10 days.

Most forecast models have Irma moving west southwest direction in the next 5 days. From there, based on GFS ensembles, it could go anywhere. Some have Irma going into the Gulf of Mexico and hitting Louisiana in 10 days. Some have Irma hitting Florida to New York. This is too early too tell and this a low confidence forecast. Anything can happen between now and around September 11, which is the 16th anniversary of horrifying terrorist attacks that killed 3,000 people and destroyed the World Trade Center.

Many on social media may have seen this.

That is bogus. For one, the NHC does not issue forecasts 13 days in advance. They only go up to 5 days in advance. Nobody knows where Irma or any hurricane will go in the next 10 days, let alone 5 days.

The latest intensity forecast are in general agreement that Irma will be a major hurricane. A couple have Irma as a Category 2 fluctuating as Category 3, which happens due to eyewall replacement cycle.

I would not be surprised if Irma becomes a Category 5 hurricane, especially when it gets around the Caribbean. Hurricanes in that part of the Atlantic rarely become Category 5 hurricanes. Irma will have to be watched for September.

A New Normal Part 1

Texas and Louisiana are slowly recovering from the ravages of Harvey. It is a national tragedy. Harvey is now a tropical depression over Mississippi dumping heavy rain over Alabama, Mississippi, and Tennessee. They have seen 5 to 8 inches/12.7 to 20.3 centimeters of rain so far. Flooding continues to be a problem for many areas. The Addicks and Barker Reservoir are still bursting at the seams with too much water.

The death toll as of 8/31/2017 is nearly 40. I suspect the death toll is going to be much higher once the flood water recedes. The question is how many. Too early to speculate at this time. If I had to guess, it could be in the hundreds. Katrina claimed more than 1,800 lives, while 9/11 claimed 3,000 lives. 9/11 is a terrorist attack. Harvey could be the deadliest natural disaster since Katrina.

With Harvey no longer a problem, I turn my attention to three areas in the tropics. There are two areas that need to be watched, Hurricane Irma, a low pressure in the Gulf of Mexico, and tropical wave emerging from West Africa. Let’s start with Irma.

Irma is now a major hurricane with 115 mph 184 km/h 100 knots with gusts of 145 mph 232 km/h 126 knots. It is moving westward at this time. Many are wondering where will Irma go. Will Irma enter the Gulf of Mexico, make landfall on the East Coast, or become a fish storm? The latest heat map from various forecast models and GFS ensemble track guidance. The GFS goes up to 10 days.

The forecast models at this point do not have have it getting close to Texas. Some have Irma entering the Gulf of Mexico and hitting the Florida Panhandle. It looks to be a East Coast threat at this point. New York City area is included in the risk area. Again, this is 10 days from now and anything can change between now and next week. Since Irma is a major hurricane, the intensity forecast is interesting.

Most maintain Irma as a Category 3 hurricane. One has it as Category 4 hurricane in two days. Some have Irma as a Category 4 hurricane in three days. I think Irma has the potential to intensify into a Category 5 hurricane, especially when it gets closer to the Caribbean. Irma could be a problem starting next week as it gets closer to land. Irma needs to be watched closely.

Another area of concern is in the Southwest Gulf of Mexico. Here is a discussion from National Hurricane Center (NHC)

ZCZC MIATWOAT ALL
TTAA00 KNHC DDHHMM

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 PM EDT Thu Aug 31 2017

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

The National Hurricane Center is issuing advisories on Hurricane
Irma, located over the eastern Atlantic Ocean. The Weather
Prediction Center is issuing advisories on Tropical Depression
Harvey, located over northern Mississippi.

1. A tropical wave emerging over the far eastern Atlantic is moving
westward at about 15 mph. Environmental conditions are expected to
become more conducive for development over the weekend and early
next week while the system moves well to the south and southwest of
the Cabo Verde Islands.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...40 percent.

2. A area of low pressure could form over the southwestern Gulf of
Mexico by the weekend, however, environmental conditions are
expected to become unfavorable for tropical cyclone formation by
that time. Interests along the Texas and Louisiana coasts are
encouraged to consult products from their local NWS Forecast Office
for more information about impacts from any non-tropical weather
systems.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...low...10 percent.

Public Advisories on Harvey are issued under WMO header WTNT34 KWNH
and under AWIPS header TCPAT4.

Forecaster Zelinsky

I do no think that will develop into something tropical. However, the moisture from it could be a factor for next week as a cold front passes. The cold front could trigger storms in areas that have been flooded. Not a good thing. That will also have to be watched.

Lastly, there is a tropical wave emerging out of West Africa. I think it will be tagged with an Invest in the next couple of days. It has a moderate chance of developing in the next five days. I would not be surprised if this becomes our next named storm, which would be Jose.

Here is what I think will happen.
-The area of thunderstorms in Southwest Gulf of Mexico bears watching, but I do not think it will develop.
-Irma needs to be watched and may pose a threat somewhere.
-Tropical wave emerging from West Africa needs to be watched. Could be Jose.

The forecast models came from NCAR-Tropical Cyclone Guidance and National Hurricane Center. Special thanks to all of them.

This is going to be a long road to recovery. It is a new normal for Texas.

Epic Flood Day 3

The helicopters flying and boats rescuing people from their flooded out homes. A sight all too common in the Houston area. The Addicks and Barker are bursting with so much water that it has be released to avoid catastrophic and widespread flooding at the cost of flooding neighborhoods. It is on the 12th anniversary of Hurricane Katrina making landfall on Louisiana and Mississippi. I am completely overwhelmed by this disaster as a weather buff. Here is a 7 day rainfall total map from Advanced Hydrologic Prediction Service (AHPS). It is unbelievable amounts I have seen.

The rainfall total are from multi-sensor (radar and rain gauge) precipitation estimates obtained from National Weather Service (NWS) River Forecast Centers (RFCs) and mosaicked by National Centers for Environmental Prediction (NCEP). There are areas that have gotten over 50 inches/127 centimeters of rain. Some areas have nearly gotten 60 inches/152.4 centimeters of rain! I would not be surprised by the end of the week, some areas get up over 60 inches/152.4 centimeters of rain!

Another mind boggling aspect is the large area that received heavy rains.

The green is where at least 10 inches/25.4 centimeters of rain fell. A large area received at least 10 inches/25.4 centimeters or greater! This has to go down as one of the largest rain events in America. We should know once Harvey passes. In the meantime, East Texas and Southwest Louisiana is getting hit by heavy rain. The latest Doppler radar out of NWS Lake Charles shows heavy rain as the storm is over the Gulf of Mexico.

Here is the 24 hour rainfall forecast from GFS, Canadian, EURO, and Weather Prediction Center (WPC).

The forecast models have the heaviest rains east of Houston. This time it is over East Texas and Southwest Louisiana. They have been getting plenty of heavy rain as well.

GFS: 11 inches/27.94 centimeters
Canadian: 10 inches/25.40 centimeters
EURO: 15 inches/38.10 centimeters
WPC: 10.74 inches/27.28 centimeters

As for Houston area, they could see still see rain, including occasional heavy rain. Looking at more moderate rain for Houston. The heavy rain has shifted to East Texas and Southwest Louisiana. Even New Orleans area is getting heavy rain and there is concern for flooding. Some of the pumps are not working, which could flood again like what happened with Katrina.

The million dollar question is where Harvey goes. Here is a heat map from various forecast models.

There is now a consensus among forecast models that Harvey will go northeast after making landfall on Southwest Louisiana as a tropical storm. Here is the latest from the National Hurricane Center. It is as of 10:00 PM or 2200 CDT:
Location: 29.0°N 93.6°W
Moving: NE at 6 mph 9 km/h 5.2 knots
Min pressure: 994 mb
Max sustained: 50 mph 80 km/h 44 knots

I do not think Harvey will intensify as it makes landfall again as a tropical storm. The reason is the core is a swirl of clouds with no thunderstorms. All the thunderstorms are north and east of the center. Once it makes landfall, Harvey moves quickly to the northeast. I say good riddance to Harvey.

Here is what I think will happen.
-Heavy rain at night, especially near and east of the center, which is East Texas and Southwest Louisiana.
-Not ruling out Houston area getting rain again tonight. Looking not as heavy. More like moderate rain.
-Rainfall amounts could range from 10 to 15 inches/25.4 to 38.1 centimeters of rain with isolated totals approaching and exceeding 20 inches/50.8 centimeters.

The forecast models came from NCAR-Tropical Cyclone Guidance, Weather.US, National Hurricane Center, and National Weather Service. Special thanks to all of them.

I am at total loss of words of with Harvey. I cannot imagine what people are going through. This a disaster that I cannot comprehend. It defies any description.

Epic Flood Day 2

Houston and the surrounding area is under water from the heavy rains of Harvey. So many people are being rescued from their flooded out homes as I type. I am so utterly stunned and horrified at what has been going on. Here is a 7 day rainfall total map from Advanced Hydrologic Prediction Service (AHPS). It is unbelievable amounts I have seen.

The highest is total is over 45 inches/114.3 centimeters! That is over Liberty County. The area of heavy rain is much larger than Allison. Heavy rain from South, Central, and East Texas. This is easily one of the largest flood events in Texas and possibly in American history. Let that all sink in. With more rain forecasted tonight and tomorrow, the total is most certainly going to rise. The forecast of 50 to 60 inches/127 to 152.4 centimeters of rain is not so far-fetched. Let’s look at the ever important rainfall forecast totals up to Friday. They are from GFS, Canadian, EURO, and Weather Prediction Center (WPC).

All of them have more rain coming. The location and amount varies.
GFS: 31 inches/78.74 centimeters
Canadian: 18 inches/45.72 centimeters
EURO: 21 inches/53.34 centimeters
WPC: 17.80 inches/45.21 centimeters

The GFS has the highest, while WPC has the lowest. The GFS and WPC have heaviest rain over Houston area. Canadian has two areas of heavy rain over Houston area and East Texas. The EURO has the heaviest over East Texas. Looks like more heavy rain will fall in the next few days from Harvey. Just the amount and where is the problem.

The million dollar question is where Harvey goes. Here is a heat map from various forecast models.

If there is some good news, the forecast models are on consensus that Harvey is eventually going to move out of Texas. The previous forecast models were low confidences as they were all over the place on where Harvey would go. This time looks Harvey is heading northeastward. However, Harvey is over the Gulf of Mexico, which allows the core to redevelop, which could mean more rain for Houston area. That is a very bad thing. Also, it could allow Harvey to reintensify and head back to land as a tropical storm. Another million dollar question, how strong will Harvey be?

Most forecast models keep Harvey as a tropical storm. Harvey has strengthened somewhat to 45 mph 72 km/h 40 knots. Some have Harvey intensifying, while a couple have Harvey becoming a strong tropical storm. I do no think Harvey will be a hurricane again despite being over the Gulf of Mexico on Tuesday. Let’s hope not.

What will tonight be like? Let’s look at High-Resolution Rapid Refresh (HRRR), North American Mesoscale Forecast System (NAM), Regional Model (RGEM), and Weather Research and Forecast (WRF-ARW, and WRF-NMM). They are at 0800Z or 3:00 AM CDT. The RGEM has it at 0900Z or 4:00 AM.

All the forecast models agree that there will be thunderstorms firing up near the center of Harvey. The locations vary by forecast model. HRRR has the heaviest rain over Beaumont area and East Texas. NAM has it over Houston area. RGEM has heaviest rain over Houston and Beaumont area. WRF-ARW has heaviest rain over Texas and Louisiana border. WRF-NMM has heaviest rain northeast of Houston. The WRF-ARW and WRF-NMM have the center of Harvey over land, which is not the case as of right now. Heavy rain is possible again tonight, but the forecast models are split on where it will happen. Like I mentioned before with tropical systems, the thunderstorms flare up at night due to the warm core and cooler surrounding temperature.

Here is what I think will happen.
-Heavy rain at night, especially near and east of the center.
-Not ruling out Houston area getting more heavy rain again tonight.
-Rainfall amounts could range from 5 to 10 inches/12.7 to 25.4 centimeters of rain with isolated totals approaching and exceeding 15 inches/38.1 centimeters.

The forecast models came from NCAR-Tropical Cyclone Guidance, Tropical Tidbits, National Hurricane Center, Weather.US, and National Weather Service. Special thanks to all of them.

I am at total loss of words of with Harvey. I cannot imagine what people are going through. This a disaster that I cannot comprehend. It defies any description.

Atlantic Hurricane Season In August

It is now August and the season is heating up. Where do most August tropical storms and hurricanes form and end up going?

Here is a GIS heat map I created. This is all August tropical storms and hurricanes from 1870 to 2015. The heat map is from within 300 miles (480 kilometers) of a point.

The Main Development Region (MDR) heats up. The Windward Islands see more tropical cyclones making landfall. Interestingly, there is a dead area around Central Caribbean and Cuba. The Gulf of Mexico and Southeast is very active. Many tropical cyclones form near land in August and make landfall. Some of the of most devastating tropical storms and hurricanes made landfall in August:
Sea Islands (1893)
San Ciriaco (1899)
Monterrey (1909)
1945 Texas Hurricane (1945)
Camille (1969)
Amelia (1978)
David (1979)
Alicia (1983)
Bob (1991)
Andrew (1992)
Charley (1998)
Charley (2004)
Katrina (2005)
Dean (2007)
Irene (2011)

Despite Amelia making landfall on July 31, 1978, the worst aspect was heavy rain from August 1-4, 1978 in Central and West Texas, where up to 46 inches (116.84 centimeters) of rain fell. The costliest hurricane occurred in August, Katrina. The previous prior to Katrina was Andrew. August has produced some of the most devastating tropical storms and hurricanes.

Texas does get hurricane landfalls in August, including major hurricanes like Allen and Alicia. Allen was a Category 5 monster and almost made landfall on Port Mansfield as a Category 5 with 180 mph winds. Had that happened, that would of been really devastating. Allen made landfall as a Category 3 hurricane with 115 mph winds. Allen was a very large hurricane upon landfall. Alicia made landfall on Galveston as a Category 3 hurricane with 115 mph winds. It was Texas’s first billion dollar disaster. Alicia was a medium size hurricane, unlike Allen. Had Alicia been Allen, Carla, or Ike size, it would been much worse.