Overnight, the offshore low that had only a 10% chance of developing into a tropical system, turned into a tropical depression and then a tropical storm called Imelda.
Houston Under Flash Flood Watch
As of 6 p.m. Monday evening, Harris County and the entire Houston area is under a flash flood watch.
If the storm stays on its present trajectory, the center should go right through the Lake Houston area. Note in the graphic above that the heaviest rainfall will be east of US59 along a line between Houston and Livingston.
Rainfall Totals
The NWS predicts the three-day total rainfall for the storm could reach 6-8 inches, though professionals caution that much higher amounts are possible. For instance, if you live east of US59 and the track of Imelda, according to Harris County meteorologist Jeff Lindner, you might get up to 10-15 inches.
As the storm approaches from the southwest, the Lake Houston area will be on the dirty side, meaning we will get higher rainfall amounts than further west.
Lake Levels Down To Create Extra Buffer Against Flooding
However, effective immediately, the Lake level will be lowered to 40.9 feet, 2.6 feet below normal. This will create an extra buffer against flooding.
Houston City Council Member Dave Martin says, “All gates will remain open until the inclement weather threat leaves the area. After the weather threat has passed, gates will stay open until a level of 41.5 feet is reached allowing for the planned maintenance project to resume.”
Dry Ground Will Absorb Initial Rainfall, Then Look Out
Because of extremely dry weather during July, August and early September, the ground should absorb much of the initial rain. However, because the rate could exceed 1-2 inches per hour at times, runoff will rapidly increase.
The first threat from this storm will be street flooding. Secondarily, it will be bayou and river flooding. You can track the latter at Harris County Flood Warning System and make sure you check out their near-real-time inundation feature.
Protective Actions
Be Prepared. People should bring their pets inside and delay travel or outdoor activities during periods of heavy rainfall. If travel is unavoidable, reduce your speed to avoid hydroplaning.
If a Flash Flood Warning is issued for your area, DO NOT travel.
Property owners should ensure that street drains and ditches are clear of debris, so storm water can flow without obstructions. Blockages of drains, ditches, and culverts are the most frequent cause of flooding in neighborhoods.
Clear Street Drains
Secure items that might float away in heavy rain and become lodged in drains or culverts. Avoid street parking to protect your vehicle and allow clear passage for response vehicles.
Turn Around, Don’t Drown®
Do not drive through flooded areas. If you see water covering the road, do not attempt to cross it. Only a few inches of water can float a vehicle . If you find yourself in a dangerous situation where your vehicle is taking on water, get out of the vehicle, get to a higher position, and call 911.
Rain may move repeatedly across the same area, causing creeks and bayous to rise and possibly exceed their banks. Stay informed of current conditions and avoid traveling near creeks and bayous.
Avoid Traveling during Periods of Heavy Rain
Rain can reduce visibility and prevent you from seeing the road ahead, which could lead to accidents.
Posted by Bob Rehak at 6 pm Tuesday, 9/17/19
749 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/09/HGX_loop.gif?fit=600%2C550&ssl=1550600adminadmin2019-09-17 18:31:272019-09-17 18:39:42Lake Level Reports in Advance of TS Imelda; Where to Find Up-to-Minute Info During Storm
Lake Charles and Houston radars show numerous clusters and bands of heavy rainfall across Gulf waters associated with deep tropical moisture. These bands will soon begin to move onshore.
Lake Charles radar shows numerous bands of heavy showers just offshore headed this way.
Houston Hobby radar shows similar banding.
Cumulative Rainfall Potential Through Friday
Excessive Rainfall Outlook on Wednesday this Week.
According to Jeff Lindner, Harris County meteorologist, the National Weather Service and National Hurricane Center, models have come into agreement. They predict a surface-low pressure system may form just offshore on Tuesday and drift inland over southeast Texas Tuesday night into Wednesday. The National Hurricane Center currently gives the system only a 10% chance of tropical formation…
…BUT regardless heavy rainfall should result.
Ingredients appear to be coming together late Tuesday through Thursday for a heavy rainfall event over the region.
Endless Supply of Tropical Moisture
According to Jeff Lindner, Harris County meteorologist, “An endless supply of moisture will pump into the region. Formation of slow-moving, training rain bands appears likely over portions of the area.”
This weather system could produce excessive rainfall, enough to saturate dry ground in a short period of time. Rains today and Tuesday especially south of I-10 will saturate dry ground. Conditions by Wednesday should support much more run-off, over a wider area.
10-15 Inches Possible
Widespread rainfall amounts of 3-6 inches will be likely over much of the area with isolated totals of 10-15 inches possible.
Hourly rainfall rates of 3-4 inches will be possible under any training bands and any slow-moving clusters resulting in rapid-onset urban flash flooding. The threat for creek, bayou, and river flooding will increase by mid-week as grounds become increasingly saturated and run-off increases.
Flash flooding will be possible.
Posted by Bob Rehak on 9/16/2019as of 9 a.m.
748 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/09/image001.gif?fit=748%2C562&ssl=1562748adminadmin2019-09-16 12:03:152019-09-16 12:03:26Potential for Heavy Rainfall, Flash Flooding Increasing This Week
Mark your calendar. On Wednesday, October 2, 2019, from 4:30 to 6:00pm, Tim Garfield, a Kingwood resident and one of the world’s leading geoscientists, will deliver a talk at the University of Houston. The subject: how the mouth bar of the San Jacinto West Fork contributed to flooding during Hurricane Harvey and what its continued presence means for the future of residents in the Lake Houston Area.
About the Speaker and Sponsor
Garfield has been one of the leaders in the grassroots movement to mitigate the influence of the mouth bar on flooding. The University of Houston History Department and Houston History Magazine have also led the movement to document the impacts of flooding on the development of Houston.
Event Details
The flier below gives more specifics about the talk.
Driving and Parking Instruction for the University of Houston Honors Commons
The event is free and open to the public. It will be held at the University of Houston Honors Commons. To learn how to get there, where to park and how to navigate from parking to the event, see below.
Debbie Z. Harwell, Ph.D., Assistant Professor of History at UH and the Editor of Houston History Magazine, arranged this event. Kudos to Garfield and Harwell for documenting the impacts of Harvey and geomorphic processes on the history of Houston.
This is one of those rare times when human history and geologic history intersect. Don’t miss it!
Posted by Bob Rehak on 9/14/2019
746 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2019/09/San-Jacinto-River-Mouth-Bar-Tim-Garflied-flyer-1.jpg?fit=1500%2C989&ssl=19891500adminadmin2019-09-14 19:37:482019-09-14 19:37:56UH Center for Public History Sponsors Talk by Tim Garfield on Influence of Mouth Bar on Harvey Flooding
Lake Level Reports in Advance of TS Imelda; Where to Find Up-to-Minute Info During Storm
Overnight, the offshore low that had only a 10% chance of developing into a tropical system, turned into a tropical depression and then a tropical storm called Imelda.
Houston Under Flash Flood Watch
As of 6 p.m. Monday evening, Harris County and the entire Houston area is under a flash flood watch.
For the latest updates visit the National Weather Service site.
Projected Path Of Storm Between US59 and I-45
If the storm stays on its present trajectory, the center should go right through the Lake Houston area. Note in the graphic above that the heaviest rainfall will be east of US59 along a line between Houston and Livingston.
Rainfall Totals
The NWS predicts the three-day total rainfall for the storm could reach 6-8 inches, though professionals caution that much higher amounts are possible. For instance, if you live east of US59 and the track of Imelda, according to Harris County meteorologist Jeff Lindner, you might get up to 10-15 inches.
As the storm approaches from the southwest, the Lake Houston area will be on the dirty side, meaning we will get higher rainfall amounts than further west.
Lake Levels Down To Create Extra Buffer Against Flooding
In advance of the storm, the Coastal Water Authority is lowering Lake Houston. The normal elevation is at 42.5 feet. As of this writing, the Coastal Water Authority shows the pool level at 41.19 feet, about 1.25 feet below normal for a planned maintenance project.
However, effective immediately, the Lake level will be lowered to 40.9 feet, 2.6 feet below normal. This will create an extra buffer against flooding.
Houston City Council Member Dave Martin says, “All gates will remain open until the inclement weather threat leaves the area. After the weather threat has passed, gates will stay open until a level of 41.5 feet is reached allowing for the planned maintenance project to resume.”
The SJRA has lowered the level of Lake Conroe according to its seasonal plan. Lake Conroe is currently at 198.71 feet, a little more than 2 feet below normal. The plan called for 199; evaporation took the rest. Currently the SJRA is releasing 0 cubic feet per second. Check the SJRA website for up to the minute reports.
Dry Ground Will Absorb Initial Rainfall, Then Look Out
Because of extremely dry weather during July, August and early September, the ground should absorb much of the initial rain. However, because the rate could exceed 1-2 inches per hour at times, runoff will rapidly increase.
The first threat from this storm will be street flooding. Secondarily, it will be bayou and river flooding. You can track the latter at Harris County Flood Warning System and make sure you check out their near-real-time inundation feature.
Protective Actions
Be Prepared. People should bring their pets inside and delay travel or outdoor activities during periods of heavy rainfall. If travel is unavoidable, reduce your speed to avoid hydroplaning.
Property owners should ensure that street drains and ditches are clear of debris, so storm water can flow without obstructions. Blockages of drains, ditches, and culverts are the most frequent cause of flooding in neighborhoods.
Clear Street Drains
Secure items that might float away in heavy rain and become lodged in drains or culverts. Avoid street parking to protect your vehicle and allow clear passage for response vehicles.
Turn Around, Don’t Drown®
Do not drive through flooded areas. If you see water covering the road, do not attempt to cross it. Only a few inches of water can float a vehicle . If you find yourself in a dangerous situation where your vehicle is taking on water, get out of the vehicle, get to a higher position, and call 911.
Monitor Official Sources for Current Information
Harris County Flood Warning System (harriscountyfws.org), Houston TranStar (houstontranstar.org), and the National Weather Service Houston/Galveston Forecast Office (weather.gov/hgx).
Monitor Stream, Bayou, and Creek Conditions
Rain may move repeatedly across the same area, causing creeks and bayous to rise and possibly exceed their banks. Stay informed of current conditions and avoid traveling near creeks and bayous.
Avoid Traveling during Periods of Heavy Rain
Rain can reduce visibility and prevent you from seeing the road ahead, which could lead to accidents.
Posted by Bob Rehak at 6 pm Tuesday, 9/17/19
749 Days since Hurricane Harvey
Potential for Heavy Rainfall, Flash Flooding Increasing This Week
Low-pressure System Will Meander Near Coast
Lake Charles and Houston radars show numerous clusters and bands of heavy rainfall across Gulf waters associated with deep tropical moisture. These bands will soon begin to move onshore.
Cumulative Rainfall Potential Through Friday
According to Jeff Lindner, Harris County meteorologist, the National Weather Service and National Hurricane Center, models have come into agreement. They predict a surface-low pressure system may form just offshore on Tuesday and drift inland over southeast Texas Tuesday night into Wednesday. The National Hurricane Center currently gives the system only a 10% chance of tropical formation…
Ingredients appear to be coming together late Tuesday through Thursday for a heavy rainfall event over the region.
Endless Supply of Tropical Moisture
According to Jeff Lindner, Harris County meteorologist, “An endless supply of moisture will pump into the region. Formation of slow-moving, training rain bands appears likely over portions of the area.”
This weather system could produce excessive rainfall, enough to saturate dry ground in a short period of time. Rains today and Tuesday especially south of I-10 will saturate dry ground. Conditions by Wednesday should support much more run-off, over a wider area.
10-15 Inches Possible
Hourly rainfall rates of 3-4 inches will be possible under any training bands and any slow-moving clusters resulting in rapid-onset urban flash flooding. The threat for creek, bayou, and river flooding will increase by mid-week as grounds become increasingly saturated and run-off increases.
Flash flooding will be possible.
Posted by Bob Rehak on 9/16/2019 as of 9 a.m.
748 Days since Hurricane Harvey
UH Center for Public History Sponsors Talk by Tim Garfield on Influence of Mouth Bar on Harvey Flooding
Mark your calendar. On Wednesday, October 2, 2019, from 4:30 to 6:00pm, Tim Garfield, a Kingwood resident and one of the world’s leading geoscientists, will deliver a talk at the University of Houston. The subject: how the mouth bar of the San Jacinto West Fork contributed to flooding during Hurricane Harvey and what its continued presence means for the future of residents in the Lake Houston Area.
About the Speaker and Sponsor
Garfield has been one of the leaders in the grassroots movement to mitigate the influence of the mouth bar on flooding. The University of Houston History Department and Houston History Magazine have also led the movement to document the impacts of flooding on the development of Houston.
Event Details
The flier below gives more specifics about the talk.
Driving and Parking Instruction for the University of Houston Honors Commons
The event is free and open to the public. It will be held at the University of Houston Honors Commons. To learn how to get there, where to park and how to navigate from parking to the event, see below.
Brought to You By…
Debbie Z. Harwell, Ph.D., Assistant Professor of History at UH and the Editor of Houston History Magazine, arranged this event. Kudos to Garfield and Harwell for documenting the impacts of Harvey and geomorphic processes on the history of Houston.
This is one of those rare times when human history and geologic history intersect. Don’t miss it!
Posted by Bob Rehak on 9/14/2019
746 Days since Hurricane Harvey