At 2:00 PM EDT on 7/22/23, the National Hurricane Center announced that Tropical Storm Don became Hurricane Don, the first Atlantic storm to achieve hurricane-force winds this year. Not only did Don form earlier than usual, it formed farther north than usual – between New England and Europe. Hurricanes hardly ever form in that area this early in the Atlantic hurricane season.
Hurricane Don’s Current Location
Location of Hurricane Don on is parallel with New Jersey.NOAA gives the orange area a 60% chance of formation in the next 7 days.
Hurricane Don’s Expected Track
NHC expects Don to decrease in strength to a tropical storm on Sunday and a tropical depression on Monday as it turns toward Europe.
Higher than Normal Sea Surface Temps Contribute to Early Formation
Warmer than normal sea surface temperatures played a role in the intensification of Don. Note the dark brown to black areas off the coasts of New England and Newfoundland. Those colors indicate a whopping 4 to 5 degrees centigrade above normal. That equals 7-9 degrees Fahrenheit.
No Hurricanes Reported Forming That Far North This Early
NHC shows that in the 165 years between 1851 and 2015, no other hurricane formed as far north as Don during this 10-day period.
Don is no threat to the Houston area. But Don’s timing may give us a clue to the type of hurricane season this will be. Both Colorado State and NOAA predicted slightly above average hurricane seasons this year.
The fourth tropical storm of the year doesn’t usually happen until August 15. And the first hurricane doesn’t usually happen until August 11.
El Niño Not a Factor in Don’s Formation
It takes the alignment of seven ingredients to form tropical cyclone. NOAA lists warm seas as #2. And we certainly have that around the world this year year, as you can see in the anomaly map above.
Wind shear from El Niño would not play a factor in deterring hurricane formation as far north as Don OR this early in the season, says Harris County’s meteorologist Jeff Lindner. “El Nino has little to no influence on our weather during the summer months (June-September),” says Lindner.
“The majority of El Nino’s influence on southern plains and Texas weather is during the fall, winter, and spring (October-May). This time of year we tend to be controlled by the sub-tropical highs around 30º N and/or the influences of the tropics from the Gulf of Mexico. This particular year the Sonoran sub-tropical high over the SW US and northern MX had thus far been the main controlling factor in our weather and El Nino has little impact on that.”
Lindner concluded, “The wind shear associated with El Niño is mainly across the southern Gulf of Mexico, much of the Caribbean Sea, and the western deep tropical Atlantic. However, wind shear thus far this hurricane season has not been overly impressive for an El Nino summer and there are some suggestions that the very warm Atlantic waters may be lessening the impacts of El Nino and its wind shear in the Atlantic basin.”
We’re into uncharted territory, so to speak. This is where it gets interesting.
Posted by Bob Rehak on 7/23/2023
2155 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2023/07/two_atl_7d0-1.png?fit=900%2C665&ssl=1665900adminadmin2023-07-22 17:35:042023-07-22 22:29:23Don Becomes First Hurricane of 2023 Atlantic Season
This morning I visited the National Hurricane Center website to see the latest tropical developments. The Houston Area has nothing to worry about at the moment. But while I was on the NHC website, I stumbled on an incredible resource. It discussed – among other things – the necessary ingredients for a tropical cyclone. It’s called the Mariner’s Tropical Cyclone Guide, updated by Dylan Flynn in May 2023.
A Treasure Trove of Information about Tropical Systems
The title sells this electronic booklet short. It’s true that the last quarter of this 86 page booklet discusses how to navigate ships and boats near tropical cyclones. But the rest is a primer on tropical systems themselves. The booklet has four chapters:
Tropical Cyclone Basics
Climatology
Monitoring Tropical Cyclones
Tropical Cyclone Evasion
Although the book is targeted at Navy and Merchant Marine personnel, the general public will find the first three parts both informative and educational. The writing is clear, crisp, and concise. And the illustrations are illuminating. Overall, a quick read.
One of the most fascinating discussions started on page 12.
Necessary Ingredients for Development and Intensification
Flynn lists seven environmental conditions necessary for tropical cyclones to form and thrive. Eliminate one, says Flynn, and the whole system starts to break down.
A pre-existing surface disturbance with thunderstorms: Tropical cyclones rely on a build-up of heat energy above them to grow and develop. A thunderstorm complex acts as a vertical transport mechanism for heat, moisture, and the cyclonic turning of winds into the upper levels of the atmosphere. This vertical transport helps tropical cyclones develop.
Warm ocean: Tropical cyclones draw on the heat energy stored in the ocean. Sea surface temperatures of at least 80ºF are needed to support development and intensification. Evaporation of this warm water begins the process of energizing the atmospheric column. The warm seas should extend at least 60 m deep, as the strong winds of a tropical cyclone cause a turbulent sea that mixes the warm surface water with cooler, deeper water.
Low vertical wind shear: Tropical cyclones rely on a vertically stacked structure to grow or maintain intensity. The ideal tropical cyclone has its upper-level circulation directly above the low-level circulation. Changes in environmental wind speed or direction with height will tilt the vertical structure. This tilting inhibits growth and may cause the system to decay.
Unstable atmosphere: Rising air is needed to warm the tropical cyclone core, and an unstable atmosphere is necessary to support rising air.
High atmospheric moisture content: Cloud formation is limited if the atmospheric column is too dry. Rising air will cool but struggle to reach the low dew point. The environment is often stable for dry parcels of air but unstable for moist air.
Upper-level outflow: An exhaust mechanism is needed above a system to perpetuate the strong upward motion. This upper-level mass removal causes the pressure at the surface to drop. As a system develops, low-level cyclonic flow pulls mass toward the center. The flow then turns upward as intense vertical motion associated with thunderstorms. This process is known as “the in-up-and-out” circulation. Without a method to dispose of the mass above a tropical cyclone, low-level converging flow toward the center will halt as the system suffocates.
Adequate Coriolis force: Due to the earth’s rotation, the Coriolis force causes tropical cyclones to spin counter-clockwise in the northern hemisphere and clockwise in the southern hemisphere. This spin is a critical component for development and intensification. Tropical cyclones rarely develop within 5 degrees of the equator, where this force is weakest. See gap in illustration below.
Other Fascinating Discussions
This is just one of dozens of fascinating topics in Flynn’s booklet. Among other things, Flynn discusses:
The exact meaning of terms used by NOAA and the National Hurricane Center. For instance, do you know the difference between a potential tropical cyclone, tropical cyclone and tropical depression? See pages 7-8.
How tropical cyclones dissipate and transition into extratropical storms. Page 14.
The size of the impact area for tropical cyclones. Page 15.
What 50 foot waves look like to a sail drone from inside the eye of hurricane. Page 22.
How dangers differ in different areas around cyclones.
Seasonal variations and the influence of El Niño.
Environmental steering currents for cyclones.
How to interpret NOAA’s technical charts and tables, such as wave heights/intervals, wind forecasts, etc.
The general public and weather enthusiasts will find a boatload of useful information in this booklet, not just the necessary ingredients for a tropical cyclone.
Posted by Bob Rehak on 7/22/2023
2153 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2023/07/20230722-Screenshot-2023-07-22-at-10.33.09-AM-1.jpg?fit=1100%2C754&ssl=17541100adminadmin2023-07-22 11:56:142023-07-22 12:07:53Necessary Ingredients for a Tropical Cyclone
As I drove by Kingwood Middle School this afternoon, sprinklers were sprinkling, grass was growing and the construction equipment was gone. All that remained were two workmen from a landscaping crew packing up their equipment. There may be small jobs yet to do. For instance, will the athletic field have football goal posts?
But I think we can safely move this project into the win column. In three years, it has gone from “distant dream” to “architectural gem” and “community showcase.”
By the start of school in three weeks, Kingwood Middle School should be fully functional – including the athletic fields and new stormwater retention basins that it never had before. See below.
Looking NE from over Pine Terrace.Looking north. The giant “Cougars” emblem on the lobby sun screen is a new addition since my last report. Giant retention basins where main entry used to be should reduce flood risk in neighborhood.
For Photographic History of Project
For photos showing the progress of Kingwood Middle School demolition and re-construction, see below.
Don Becomes First Hurricane of 2023 Atlantic Season
At 2:00 PM EDT on 7/22/23, the National Hurricane Center announced that Tropical Storm Don became Hurricane Don, the first Atlantic storm to achieve hurricane-force winds this year. Not only did Don form earlier than usual, it formed farther north than usual – between New England and Europe. Hurricanes hardly ever form in that area this early in the Atlantic hurricane season.
Hurricane Don’s Current Location
Hurricane Don’s Expected Track
NHC expects Don to decrease in strength to a tropical storm on Sunday and a tropical depression on Monday as it turns toward Europe.
Higher than Normal Sea Surface Temps Contribute to Early Formation
Warmer than normal sea surface temperatures played a role in the intensification of Don. Note the dark brown to black areas off the coasts of New England and Newfoundland. Those colors indicate a whopping 4 to 5 degrees centigrade above normal. That equals 7-9 degrees Fahrenheit.
No Hurricanes Reported Forming That Far North This Early
NHC shows that in the 165 years between 1851 and 2015, no other hurricane formed as far north as Don during this 10-day period.
Average Dates of Formation for Named Storms
Usually, the Atlantic Basin doesn’t see its first named hurricane until August 11. So Don is a month ahead of schedule on that count.
Don is no threat to the Houston area. But Don’s timing may give us a clue to the type of hurricane season this will be. Both Colorado State and NOAA predicted slightly above average hurricane seasons this year.
The fourth tropical storm of the year doesn’t usually happen until August 15. And the first hurricane doesn’t usually happen until August 11.
El Niño Not a Factor in Don’s Formation
It takes the alignment of seven ingredients to form tropical cyclone. NOAA lists warm seas as #2. And we certainly have that around the world this year year, as you can see in the anomaly map above.
Wind shear from El Niño would not play a factor in deterring hurricane formation as far north as Don OR this early in the season, says Harris County’s meteorologist Jeff Lindner. “El Nino has little to no influence on our weather during the summer months (June-September),” says Lindner.
“The majority of El Nino’s influence on southern plains and Texas weather is during the fall, winter, and spring (October-May). This time of year we tend to be controlled by the sub-tropical highs around 30º N and/or the influences of the tropics from the Gulf of Mexico. This particular year the Sonoran sub-tropical high over the SW US and northern MX had thus far been the main controlling factor in our weather and El Nino has little impact on that.”
Lindner concluded, “The wind shear associated with El Niño is mainly across the southern Gulf of Mexico, much of the Caribbean Sea, and the western deep tropical Atlantic. However, wind shear thus far this hurricane season has not been overly impressive for an El Nino summer and there are some suggestions that the very warm Atlantic waters may be lessening the impacts of El Nino and its wind shear in the Atlantic basin.”
We’re into uncharted territory, so to speak. This is where it gets interesting.
Posted by Bob Rehak on 7/23/2023
2155 Days since Hurricane Harvey
Necessary Ingredients for a Tropical Cyclone
This morning I visited the National Hurricane Center website to see the latest tropical developments. The Houston Area has nothing to worry about at the moment. But while I was on the NHC website, I stumbled on an incredible resource. It discussed – among other things – the necessary ingredients for a tropical cyclone. It’s called the Mariner’s Tropical Cyclone Guide, updated by Dylan Flynn in May 2023.
A Treasure Trove of Information about Tropical Systems
The title sells this electronic booklet short. It’s true that the last quarter of this 86 page booklet discusses how to navigate ships and boats near tropical cyclones. But the rest is a primer on tropical systems themselves. The booklet has four chapters:
Although the book is targeted at Navy and Merchant Marine personnel, the general public will find the first three parts both informative and educational. The writing is clear, crisp, and concise. And the illustrations are illuminating. Overall, a quick read.
One of the most fascinating discussions started on page 12.
Necessary Ingredients for Development and Intensification
Flynn lists seven environmental conditions necessary for tropical cyclones to form and thrive. Eliminate one, says Flynn, and the whole system starts to break down.
Other Fascinating Discussions
This is just one of dozens of fascinating topics in Flynn’s booklet. Among other things, Flynn discusses:
The general public and weather enthusiasts will find a boatload of useful information in this booklet, not just the necessary ingredients for a tropical cyclone.
Posted by Bob Rehak on 7/22/2023
2153 Days since Hurricane Harvey
Goal! Kingwood Middle School Reconstruction Reaches Finals
As I drove by Kingwood Middle School this afternoon, sprinklers were sprinkling, grass was growing and the construction equipment was gone. All that remained were two workmen from a landscaping crew packing up their equipment. There may be small jobs yet to do. For instance, will the athletic field have football goal posts?
But I think we can safely move this project into the win column. In three years, it has gone from “distant dream” to “architectural gem” and “community showcase.”
By the start of school in three weeks, Kingwood Middle School should be fully functional – including the athletic fields and new stormwater retention basins that it never had before. See below.
For Photographic History of Project
For photos showing the progress of Kingwood Middle School demolition and re-construction, see below.
Job Well Done
Congratulations to Humble ISD staff, Superintendent Elizabeth Fagan, School Board, and contractors. Job well done!
This is a great example of how new construction can reduce flood risk…when people care.
Posted by Bob Rehak on 7/20/2023
2151 Days since Hurricane Harvey