5/14/25 – This morning, I gave a presentation that compared the pace of downstream flood mitigation with the pace of upstream development. Are we gaining or losing ground in the Lake Houston Area?
Presentation Connects Many Dots
Answering that question requires connecting many dots. Here are the slides from the presentation with my narrative.
As new upstream development adds impervious cover (roads and roofs) that can increase and accelerate runoff, building flood peaks higher and faster. And that can erode the safety of downstream residents. Managing flood risk becomes a struggle between competing forces.
MoCo One of Fastest Growing Counties in Country
The Lake Houston Area lies downstream from one of the fastest growing counties in the country. Montgomery County (MoCo) grew 68% in the last 15 years and 4.8% in 12 months recently. MoCo is currently the seventh fastest growing county in the entire country.
Ryko Exemplifies Danger of Upstream Development
Let’s look at a proposed MoCo development in the headwaters of Lake Houston. A company named Ryko bought 5,500 acres about a quarter mile west of Kingwood. It’s in the southern part of a triangle formed by Spring Creek, the San Jacinto West Fork and the Grand Parkway.
US59 Bridge in foreground by the confluence of the Sand Jacinto West Fork and Spring Creek.
“Like Aiming a Firehose At Kingwood”
Ryko, which is a Syrian-owned company, is reportedly working with Wan Bridge, a Chinese company, to develop 7,000 homes on the property. One of the leading hydrologists in the area told me that developing this property would be “like aiming a firehose at Kingwood.”
Many “Guardrails” Being Removed
Government has established many guardrails over time to protect people from insufficiently mitigated upstream development. But many of the guardrails are being removed. Or people are trying to remove them.
In this case:
A change to the state property code in 2023 gave developers the right to opt out of a city’s extra territorial jurisdiction (ETJ). ETJs lay the groundwork for future annexation by ensuring new infrastructure meets the standards of areas that might annex them someday. But if developments are not in an ETJ, they could change plats without approval.
Two bills pending in the legislature, HB23 and its companion SB2354, would essentially let developers “self-permit” by hiring engineering firms that replace government oversight.
The Endangered Species Act (ESA) constrains development in areas inhabited by threatened or endangered species. But Executive Order 14192 could change that. The US Fish and Wildlife Service has proposed a change under the order that means Ryko would no longer have to work around endangered species on its property.
An ex-Senior VP of Ryko for 21 years is now chair of the Houston Planning Commission. She still reportedly represents the company as an independent consultant,
The Montgomery County Drainage Criteria Manual hasn’t had a serious update for 40 years. The County still allows controversial practices, such as hydrologic timing surveys, to “prove” that upstream developments have no adverse impact on downstream residents.
Let’s take a closer look at the Ryko property with these issues in mind.
Upstream Development Almost Entirely in Floodplains
With that as a backdrop, what’s going on with the Ryko land? The map in the background for this next slide comes from Ryko’s Drainage Impact Analysis. It shows that their property (outlined in red) lies at the confluence of four major streams. All that blue represents floodplains and floodways.
Property outline and stream names enhanced for readability.
How Bad Is Ryko’s Flood Risk?
FEMA’s base-flood-elevation viewer shows that at the southern end of Ryko’s property, any homes would be under 25 feet of water in a 500-year flood (18.7 feet in a 100-year flood). Even at the higher elevations farther north, homes would be under 7 feet of water in a major flood.
Frequent Bald Eagle Sightings
Homeowners father north report frequent sightings of bald eagles. They believe the eagles live on Ryko’s property which is currently wilderness. One resident sent me a video of two eagles that landed in a tree right outside her living room window.
The Texas Water Code contains a rule that states upstream development can have “No Adverse Impact” on downstream neighbors. To prove no adverse impact, engineers compare estimated pre- and post-development runoff.
If post-development estimates are less than or equal to pre-development, they satisfy the requirement.
Estimates Based on Hydrologic Timing Not Always Accurate
But how accurate are those estimates? Montgomery County’s antiquated drainage criteria manual still lets engineers use hydrologic timing surveys, a practice now prohibited by the City of Houston and Harris County for several reasons.
Timing studies let developers avoid building detention basins if they can show that their development’s stormwater “beats the peak” of a flood. The theory: they aren’t adding to the peak.
Not building detention basins saves developers money and adds to the number of salable lots. But “beat the peak” studies have serious limitations and can often mislead.
They assume, for instance, a uniform storm across an entire watershed. But that rarely happens. Imagine the case of a storm like Harvey, which approaches from the south as developers to the north rush to get their water to the river. God help the people caught in the middle.
Timing surveys, in the case of Montgomery County, are also based on decades old data that ignores the cumulative impacts of other developments over time.
How Avoiding Detention Can Add to Flood Peaks
What often happens in reality is that you get higher peaks than if you had built detention. This graph shows three lines. The two at the bottom show typical pre- and post-development runoff rates where/when hydrologic timing studies are prohibited.
Not building detention often leads to earlier, higher peaks.
The height difference could be the difference between flooding or not flooding.
MoCo Still Doesn’t Require More Reliable Method
In short, building stormwater detention is a sure thing. Hydrologic timing is not.
Banning hydrologic timing studies would force developers to design systems that TRULY detain and slow runoff. But Montgomery County still permits timing studies. The County’s new Drainage Criteria Manual that prohibits them has been sitting on the shelf for more than a year.
Downstream Mitigation Slowing
Now, let’s look at what downstream residents are doing to offset the impacts of upstream development.
More floodgates on Lake Houston to speed up output
Upstream detention to reduce input.
Dredging is Highlight to Date…
Dredging continues. We’ve spent approximately $200 million to date and that total is still increasing.
Images shot current West Fork dredging plan, location of dredge by FM1960, and spoils placement area by Luce Bayou.
…But More Sediment Keeps Coming
After the Army Corps finished its emergency West Fork Dredging Project, they recommended regular maintenance dredging to ensure our rivers had sufficient conveyance and our drainage ditches were not blocked. State Representative Charles Cunningham authored HB1532 to create a dredging district for the Lake Houston Area.
HB1532 passed overwhelmingly in the House and is now waiting to be heard by Senator Paul Bettencourt’s Local Government committee in the Senate.
But this legislative session ends in two weeks. Any bill not out of committee by this Friday is effectively dead. And Bettencourt has not yet scheduled Cunningham’s bill for a hearing.
Construction on More Floodgates Not Likely Before 2027
The additional floodgates on Lake Houston have been delayed repeatedly for various reasons. Simultaneously, the Coastal Water Authority (CWA) is looking at the costs of repairing the dam and replacing it altogether. The 70+ year old dam is near the end of its useful life.
CWA board member Dan Huberty stated that engineering for additional gates should be complete by 2027. At that time, the project will go out for bids.
The CWA won’t receive preliminary reports on dam repairs and replacement until at least July of this year.
No Progress on Upstream Detention, None Likely Anytime Soon
Meanwhile, virtually nothing has happened yet in terms of upstream detention. The San Jacinto River Authority identified 16 areas for upstream detention basins/lakes in its River Basin Master Drainage Study.
SJRA has no construction funds. So many of the projects were incorporated into the state flood plan. But the state’s Flood Infrastructure Fund does not have a committed revenue stream.
The Texas Water Development Board has about a billion dollars currently available to build $54 billion worth of requests in the flood plan.
So keep the pressure on elected representatives who can protect your family.
Posted by Bob Rehak on 5/14/25
2815 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2025/05/DOTS-Slide17.jpeg?fit=1100%2C619&ssl=16191100adminadmin2025-05-14 17:49:322025-05-14 17:49:33Is Downstream Flood Mitigation Keeping Pace with Upstream Development?
5/12/25 – This post contains a guide compiled with the help of ChatGPT that describes how to reduce your flood risk when buying a home.
A major flood occurs somewhere in Southeast Texas on average once every 2.5 years, according to data compiled by Harris County Flood Control District. Flooding is THE NUMBER ONE THREAT to Houston area home owners no matter whether you consider frequency, damage potential, or financial impact.
Home and heirlooms flooded during Hurricane Harvey
Why Does Houston Flood So Much?
The main factors that increase flood risk fall into four categories:
Natural and Geographic Factors
Topography: Houston has many low-lying or flat areas drain slowly and accumulate water easily.
Soil type: Our clay-heavy and compacted soils absorb less water, increasing runoff.
Proximity to water bodies: Many rivers, bayous, and streams converge near the coast, making us more vulnerable to riverine and coastal flooding.
Rainfall intensity: The area receives intense and prolonged rainfalls.
Subsidence caused by excessive groundwater withdrawals can create bowls in the landscape and alter the gradient of streams.
Land Use and Development
Urbanization: Houston has grown rapidly, replacing vegetation with impervious surfaces (e.g., pavement, roofs). That drastically increases stormwater runoff.
Building in floodplains: Encroachment into natural flood zones has reduced flood storage capacity and exposed structures to damage.
Loss of wetlands and forests: Natural systems that absorb and slow runoff have been diminished.
Compacted or altered terrain: Grading and clearing land have disrupted natural drainage patterns.
Drainage and Infrastructure Deficiencies
Undersized storm drains or culverts built in decades ago often cannot handle large storm volumes.
Aging or poorly maintained systems: Blocked drains, eroded ditches, or failing levees increase risk.
Inadequate detention/retentionupstream: If runoff is not slowed or held temporarily, downstream flooding worsens.
Lack of regional coordination: Piecemeal or inconsistent regulations across the region complicate drainage problems.
Climate and Weather Patterns
More intense rainfall events: Houston’s warm atmosphere, proximity to the Gulf, complex weather patterns cause legendary downpours.
Rising sea levels: Increases the extent and impact of storm surge in coastal areas.
Back-to-back storms: Frequent rainfalls can saturate soils and fill channels, reducing capacity to absorb new runoff.
Houston Home Buyer’s Guide to Reducing Flood Risk
So what’s a newcomer to the region supposed to do? Or even a long-time resident who is relocating within the area?
I asked ChatGPT to help me put together a home-buyer’s guide for those who wish to reduce flood risk. It compiled a comprehensive guide almost 9,000 words long, specifically geared to the Houston region. However, it contains valuable information for other areas, too.
The guide covers what to look for during a property visit, online tools to assess flood risk, reviewing a home’s flood history, understanding elevation certificates, local floodplain regulations, and flood insurance considerations.
Major sections include:
Identifying the floodplain and flood-zone designations
Locations near waterways or reservoirs
Property elevation
Drainage infrastructure and proximity to drains
Neighborhood flood history
Lot grading and slopes
Signs of water pooling and poor drainage
Nearby bayous, ditches and low areas
House elevation and foundation design
Gutters, downspouts and drainage features
Evidence of past flooding and water damage
Tools and websites for evaluating flood risk (FEMA, Harris County Flood Education Mapping Tool, First Street Foundation)
Reviewing a property’s flood history
Seller’s disclosure notices
CLUE report (Comprehensive Loss Underwriting Exchange), an insurance claims history
Elevation Certificates and Base Flood Elevations
The impact of elevation on insurance premiums
Floodplain regulations and permits
How floodplain regulations could impact improvements you might want to make to an older home
It’s filled with valuable advice and reflects many of the themes I have posted about since Harvey.
Buyers Must Exercise More Caution than Ever
One last piece of advice. With FEMA and HUD under fire from DOGE and with the future of flood-mitigation funding in doubt, buyers must exercise more caution than ever. It’s also highly recommended reading for real estate agents.
Don’t expect the government to come to your rescue after a future flood. During Harvey:
154,170 homes across the county flooded in Harvey.
That’s eight one-hundredths of one percent. You can find far better odds playing the Texas Lottery.
Posted by Bob Rehak on 5/12/25
2813 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2020/01/IMG-3142-scaled-e1747098548322.jpg?fit=1100%2C825&ssl=18251100adminadmin2025-05-12 20:30:192025-05-12 20:38:35How to Reduce Your Flood Risk When Buying a Home
5/11/25 – A study published in the November 2024 edition of the Journal of Applied Meteorology and Climatology by researchers from Louisiana State University and Texas A&M examined stalling and rapidly intensifying tropical cyclones.
After analyzing 1,274 storms going back to 1900, they found one of the primary areas for such storms to strike is along the central Gulf Coast. They also found that, the estimated annual frequency of stalls significantly increased from 1966 – 2020 – by 1.5% year.
Lead author of the study, called Stalling North Atlantic Tropical Cyclones, is Jill C. Trepanier of LSU. Others include: John Nielsen-Gammon of Texas A&M; and Vincent Brown, Derek Thompson and Barry Keim, all of LSU.
Stalling Storms More Damaging
The authors found that, “Storms that stall tend to have a longer average duration than those that do not stall in all categories.” By that they mean levels of intensity (Cat 1 through 5).
They say stalling storms increase rainfall rates, storm surge heights and exposure to high winds including tornado activity. “Storms that slow down or stall can increase total damage by prolonging the exposure time to intense conditions,” they say.
Stalling Storms Clustered in Central Gulf, Late in Season
They also found that stalls tend to cluster in certain places. Those include, but are not limited to the central Gulf Coast.
And they happen more often late in the season during September and October.
“Stalls tend to occur in similar places over time and happen more frequently later in the hurricane season (October) when compared to the middle (August). Emergency managers can use this information to identify the likely location and timing for stalls throughout the North Atlantic tropical cyclone season,” say the authors.
Definition of Stalling
The researchers define a stalling cyclone as one that moves less than 200 km in 72 hours. “Potentially most devastating are those stalls within 200 km of the coast, but even more so, those that stall over or partially over land.”
“This is important for emergency managers to realize,” they say, “as those stalling near the coast will have a higher potential to inflict more damage to a population.” And storms that also rapidly intensify also give:
Emergency managers less time to evacuate people.
Residents less time to prepare.
The researchers also found that Category 3+ storms such as Hurricane Harvey persist longer than weaker tropical cyclones, providing more stall opportunities. Harvey, they say, dumped more rain than any stalling storm in recorded history. They examined the historical record going back to 1899.
Harvey track in 2017. Notice how dots get closer together as storm stalled over Texas.Each dot represents 6 hours.
Rapidly Intensifying Storms Also Becoming More Frequent
These studies suggest that rapidly intensifying storms have become more frequent and are occurring closer to the coast in recent years. Rapidly intensifying storms make evacuations more difficult. More people must move in less time and with less warning.
Coastal Areas More Densely Populated
According to NOAA, coastal areas are notably more densely populated than inland regions. For instance, coastal shoreline counties have a population density more than five times greater than the U.S. average.
Approximately 39% of the U.S. population lives in coastal shoreline counties, which comprise less than 10% of the nation’s land area (excluding Alaska).
Additional Research
Before concluding, the authors called for more research on the rainfall recurrence intervals associated with stalling cyclones. They also say future analysis should include a deeper dive on rapid intensification.
Individuals Should Research Preparation
In the meantime, the best thing people living in coastal areas can do is prepare. Forecasters predict an above-average hurricane season, which starts in about two weeks. The National Hurricane Center has produced an excellent series of videos to help you protect your family and property.
Is Downstream Flood Mitigation Keeping Pace with Upstream Development?
5/14/25 – This morning, I gave a presentation that compared the pace of downstream flood mitigation with the pace of upstream development. Are we gaining or losing ground in the Lake Houston Area?
Presentation Connects Many Dots
Answering that question requires connecting many dots. Here are the slides from the presentation with my narrative.
Offsetting Forces
As new upstream development adds impervious cover (roads and roofs) that can increase and accelerate runoff, building flood peaks higher and faster. And that can erode the safety of downstream residents. Managing flood risk becomes a struggle between competing forces.
MoCo One of Fastest Growing Counties in Country
The Lake Houston Area lies downstream from one of the fastest growing counties in the country. Montgomery County (MoCo) grew 68% in the last 15 years and 4.8% in 12 months recently. MoCo is currently the seventh fastest growing county in the entire country.
Ryko Exemplifies Danger of Upstream Development
Let’s look at a proposed MoCo development in the headwaters of Lake Houston. A company named Ryko bought 5,500 acres about a quarter mile west of Kingwood. It’s in the southern part of a triangle formed by Spring Creek, the San Jacinto West Fork and the Grand Parkway.
“Like Aiming a Firehose At Kingwood”
Ryko, which is a Syrian-owned company, is reportedly working with Wan Bridge, a Chinese company, to develop 7,000 homes on the property. One of the leading hydrologists in the area told me that developing this property would be “like aiming a firehose at Kingwood.”
Many “Guardrails” Being Removed
Government has established many guardrails over time to protect people from insufficiently mitigated upstream development. But many of the guardrails are being removed. Or people are trying to remove them.
In this case:
Let’s take a closer look at the Ryko property with these issues in mind.
Upstream Development Almost Entirely in Floodplains
With that as a backdrop, what’s going on with the Ryko land? The map in the background for this next slide comes from Ryko’s Drainage Impact Analysis. It shows that their property (outlined in red) lies at the confluence of four major streams. All that blue represents floodplains and floodways.
How Bad Is Ryko’s Flood Risk?
FEMA’s base-flood-elevation viewer shows that at the southern end of Ryko’s property, any homes would be under 25 feet of water in a 500-year flood (18.7 feet in a 100-year flood). Even at the higher elevations farther north, homes would be under 7 feet of water in a major flood.
Frequent Bald Eagle Sightings
Homeowners father north report frequent sightings of bald eagles. They believe the eagles live on Ryko’s property which is currently wilderness. One resident sent me a video of two eagles that landed in a tree right outside her living room window.
How Developers Document “No Adverse Impact”
The Texas Water Code contains a rule that states upstream development can have “No Adverse Impact” on downstream neighbors. To prove no adverse impact, engineers compare estimated pre- and post-development runoff.
If post-development estimates are less than or equal to pre-development, they satisfy the requirement.
Estimates Based on Hydrologic Timing Not Always Accurate
But how accurate are those estimates? Montgomery County’s antiquated drainage criteria manual still lets engineers use hydrologic timing surveys, a practice now prohibited by the City of Houston and Harris County for several reasons.
Timing studies let developers avoid building detention basins if they can show that their development’s stormwater “beats the peak” of a flood. The theory: they aren’t adding to the peak.
Not building detention basins saves developers money and adds to the number of salable lots. But “beat the peak” studies have serious limitations and can often mislead.
They assume, for instance, a uniform storm across an entire watershed. But that rarely happens. Imagine the case of a storm like Harvey, which approaches from the south as developers to the north rush to get their water to the river. God help the people caught in the middle.
Timing surveys, in the case of Montgomery County, are also based on decades old data that ignores the cumulative impacts of other developments over time.
How Avoiding Detention Can Add to Flood Peaks
What often happens in reality is that you get higher peaks than if you had built detention. This graph shows three lines. The two at the bottom show typical pre- and post-development runoff rates where/when hydrologic timing studies are prohibited.
The height difference could be the difference between flooding or not flooding.
MoCo Still Doesn’t Require More Reliable Method
In short, building stormwater detention is a sure thing. Hydrologic timing is not.
Banning hydrologic timing studies would force developers to design systems that TRULY detain and slow runoff. But Montgomery County still permits timing studies. The County’s new Drainage Criteria Manual that prohibits them has been sitting on the shelf for more than a year.
Downstream Mitigation Slowing
Now, let’s look at what downstream residents are doing to offset the impacts of upstream development.
Compared to the period after Harvey, that activity has slowed. The Lake Houston Area Task Force identified three crucial needs to reduce flood risk.
Dredging is Highlight to Date…
Dredging continues. We’ve spent approximately $200 million to date and that total is still increasing.
…But More Sediment Keeps Coming
After the Army Corps finished its emergency West Fork Dredging Project, they recommended regular maintenance dredging to ensure our rivers had sufficient conveyance and our drainage ditches were not blocked. State Representative Charles Cunningham authored HB1532 to create a dredging district for the Lake Houston Area.
HB1532 passed overwhelmingly in the House and is now waiting to be heard by Senator Paul Bettencourt’s Local Government committee in the Senate.
But this legislative session ends in two weeks. Any bill not out of committee by this Friday is effectively dead. And Bettencourt has not yet scheduled Cunningham’s bill for a hearing.
Construction on More Floodgates Not Likely Before 2027
The additional floodgates on Lake Houston have been delayed repeatedly for various reasons. Simultaneously, the Coastal Water Authority (CWA) is looking at the costs of repairing the dam and replacing it altogether. The 70+ year old dam is near the end of its useful life.
CWA board member Dan Huberty stated that engineering for additional gates should be complete by 2027. At that time, the project will go out for bids.
The CWA won’t receive preliminary reports on dam repairs and replacement until at least July of this year.
No Progress on Upstream Detention, None Likely Anytime Soon
Meanwhile, virtually nothing has happened yet in terms of upstream detention. The San Jacinto River Authority identified 16 areas for upstream detention basins/lakes in its River Basin Master Drainage Study.
SJRA has no construction funds. So many of the projects were incorporated into the state flood plan. But the state’s Flood Infrastructure Fund does not have a committed revenue stream.
The Texas Water Development Board has about a billion dollars currently available to build $54 billion worth of requests in the flood plan.
So keep the pressure on elected representatives who can protect your family.
Posted by Bob Rehak on 5/14/25
2815 Days since Hurricane Harvey
How to Reduce Your Flood Risk When Buying a Home
5/12/25 – This post contains a guide compiled with the help of ChatGPT that describes how to reduce your flood risk when buying a home.
A major flood occurs somewhere in Southeast Texas on average once every 2.5 years, according to data compiled by Harris County Flood Control District. Flooding is THE NUMBER ONE THREAT to Houston area home owners no matter whether you consider frequency, damage potential, or financial impact.
Why Does Houston Flood So Much?
The main factors that increase flood risk fall into four categories:
Houston Home Buyer’s Guide to Reducing Flood Risk
So what’s a newcomer to the region supposed to do? Or even a long-time resident who is relocating within the area?
I asked ChatGPT to help me put together a home-buyer’s guide for those who wish to reduce flood risk. It compiled a comprehensive guide almost 9,000 words long, specifically geared to the Houston region. However, it contains valuable information for other areas, too.
The guide covers what to look for during a property visit, online tools to assess flood risk, reviewing a home’s flood history, understanding elevation certificates, local floodplain regulations, and flood insurance considerations.
Major sections include:
Here is a link to the entire ChatGPT deep research report, “The Houston Home Buyer’s Guide to Reducing Flooding.”
It’s filled with valuable advice and reflects many of the themes I have posted about since Harvey.
Buyers Must Exercise More Caution than Ever
One last piece of advice. With FEMA and HUD under fire from DOGE and with the future of flood-mitigation funding in doubt, buyers must exercise more caution than ever. It’s also highly recommended reading for real estate agents.
Don’t expect the government to come to your rescue after a future flood. During Harvey:
That’s eight one-hundredths of one percent. You can find far better odds playing the Texas Lottery.
Posted by Bob Rehak on 5/12/25
2813 Days since Hurricane Harvey
Study Finds Stalling Cyclones Increasing
5/11/25 – A study published in the November 2024 edition of the Journal of Applied Meteorology and Climatology by researchers from Louisiana State University and Texas A&M examined stalling and rapidly intensifying tropical cyclones.
After analyzing 1,274 storms going back to 1900, they found one of the primary areas for such storms to strike is along the central Gulf Coast. They also found that, the estimated annual frequency of stalls significantly increased from 1966 – 2020 – by 1.5% year.
Lead author of the study, called Stalling North Atlantic Tropical Cyclones, is Jill C. Trepanier of LSU. Others include: John Nielsen-Gammon of Texas A&M; and Vincent Brown, Derek Thompson and Barry Keim, all of LSU.
Stalling Storms More Damaging
The authors found that, “Storms that stall tend to have a longer average duration than those that do not stall in all categories.” By that they mean levels of intensity (Cat 1 through 5).
They say stalling storms increase rainfall rates, storm surge heights and exposure to high winds including tornado activity. “Storms that slow down or stall can increase total damage by prolonging the exposure time to intense conditions,” they say.
Stalling Storms Clustered in Central Gulf, Late in Season
They also found that stalls tend to cluster in certain places. Those include, but are not limited to the central Gulf Coast.
And they happen more often late in the season during September and October.
“Stalls tend to occur in similar places over time and happen more frequently later in the hurricane season (October) when compared to the middle (August). Emergency managers can use this information to identify the likely location and timing for stalls throughout the North Atlantic tropical cyclone season,” say the authors.
Definition of Stalling
The researchers define a stalling cyclone as one that moves less than 200 km in 72 hours. “Potentially most devastating are those stalls within 200 km of the coast, but even more so, those that stall over or partially over land.”
“This is important for emergency managers to realize,” they say, “as those stalling near the coast will have a higher potential to inflict more damage to a population.” And storms that also rapidly intensify also give:
The researchers also found that Category 3+ storms such as Hurricane Harvey persist longer than weaker tropical cyclones, providing more stall opportunities. Harvey, they say, dumped more rain than any stalling storm in recorded history. They examined the historical record going back to 1899.
Rapidly Intensifying Storms Also Becoming More Frequent
The authors of the “stalling” study also reviewed other studies such as Kaplan et al. (2015) and Benedetto and Trepanier (2020).
These studies suggest that rapidly intensifying storms have become more frequent and are occurring closer to the coast in recent years. Rapidly intensifying storms make evacuations more difficult. More people must move in less time and with less warning.
Coastal Areas More Densely Populated
According to NOAA, coastal areas are notably more densely populated than inland regions. For instance, coastal shoreline counties have a population density more than five times greater than the U.S. average.
Approximately 39% of the U.S. population lives in coastal shoreline counties, which comprise less than 10% of the nation’s land area (excluding Alaska).
Additional Research
Before concluding, the authors called for more research on the rainfall recurrence intervals associated with stalling cyclones. They also say future analysis should include a deeper dive on rapid intensification.
Individuals Should Research Preparation
In the meantime, the best thing people living in coastal areas can do is prepare. Forecasters predict an above-average hurricane season, which starts in about two weeks. The National Hurricane Center has produced an excellent series of videos to help you protect your family and property.
Posted by Bob Rehak on 5/11/25
2812 Days since Hurricane Harvey