By Jeff Lindner, Harris County Flood Control District’s Director Hydrologic Operations Division/Meteorologist, with a few minor edits for a non-technical audience.
There have been many comparisons of this summer to that of 2011 with respect to the heat and drought. Below, see the comparison of drought, water supply storage, and heat between 2011 and 2023.
Rainfall (Jan 1 to Aug 23)
2023 Rainfall
2023 Departure
2011 Rainfall
2011 Departure
BUSH IAH
29.97
-2.29
10.93
-21.33
Hobby
22.20
-11.83
10.47
-23.56
Conroe
28.41
-3.25
17.54
-14.69
College Station
21.47
-3.79
10.57
-14.12
As the table above shows, the rainfall departures in 2011 were significantly greater at all sites. That indicates a much more significant drought in 2011 than in 2023.
Rainfall departures in 2023 were tempered by a wet April and May over much of the area, while in 2011 drought conditions in the spring were some of the worst ever recorded with many areas recording their driest spring ever. 2011 was also preceded by dryness in late 2010 that helped to worsen the 2011 drought conditions and water supply concerns.
Rainfall at Hobby Airport in 2011 (Feb-May) was only 1.31 inches compared to 2023 of 11.85 inches.
While it is clear that 2011 was worse with respect to lack of rainfall, the abrupt change in rainfall from late spring into the summer of 2023 has “shocked” vegetation across the region.
Additionally, it has been hotter to some degree (especially overnight) in 2023 and the flash drought has been severe with nearly the entire area drought free in early June to all of the area in severe to extreme drought as of August 15th.
The very warm maximum temperatures and record “high” low temperatures over the region have resulted in rapid degradation of vegetation health. Tree losses were staggering in 2011 and the area is starting to see losses mounting in 2023, but far below what was experienced at this point in 2011.
Comparison of Drought Conditions, Extents
In 2011, exceptional drought covered most of the state.
In 2023, exceptional drought is minuscule by comparison.
Reservoir Storage
2011 also featured significant drawdown on area lakes and water supply reservoirs as the longer duration “hydrological” drought resulted in record or near record low inflows to several lakes.
As of this afternoon, statewide reservoir storage is at 69.8% of capacity compared to 65.4% on this date in 2011. A low of 58.5% was recorded on 11-18-2011.
The table below summarizes storage capacities for the first 2 weeks of August 2023 compared to 2011:
2023 Capacity
2023 Departure
2011 Capacity
2011 Departure
Conroe
92.5%
-1.60
82.0%
-4.05
Houston
96.4%
-.42
81.0%
-6.50
Livingston
89.0%
-2.38
90.0%
-2.08
Texanna
77.2%
-3.83
52.0%
-9.62
Somerville
79.0%
-2.90
49.0%
-8.06
Travis
39.4%
-47.96
43.0%
-44.50
Buchanan
49.7%
-22.55
51.0%
-23.00
Lake Conroe and Houston are much better off than in 2011 with Lake Livingston being nearly the same and both Somerville and Texanna significantly better off in 2023 versus 2011. This matches well with the rainfall trends experienced in late Spring over the area which for the most part filled Houston, Conroe, Somerville, and Texanna to near capacity, allowing the recent dryness to be well handled.
This was not the case in 2011 when a very dry spring and dryness from late 2010 was already depleting capacities prior to the summer increased demand and evaporation losses.
Central Texas Lake Levels Lower in 2023
However, across central Texas at Travis and Buchanan, conditions are worse at this point than in 2011. Travis is 3.46 ft lower in 2023 than in 2011 and Buchanan is 0.45 ft lower.
Central Texas and the highland lakes chain have been in drought conditions since the summer of 2022 and rainfall this spring was not as significant in this area compared to coastal areas of the state and SE TX, so lake inflows have been very low and evaporation and demand maximized.
Heat Comparison
In addition to the drought conditions, it has been brutally hot. But how does 2023 compare to 2011 with respect to 100 degree or hotter afternoons? This is only part of the story of the heat of 2023, as overnight low temperatures have also been warm.
College Station has recorded 42 days with a morning low at or above 80 degrees, BUSH IAH 41, and Hobby 44. However, Galveston has recorded 64 days this summer at or above 80 degrees for a morning low.
The above average Gulf of Mexico waters are resulting in exceptional overnight heat along the coast.
Jeff Lindner, Harris County Meteorologist
Days At or Above 100
Days At or Above 105
2023
2011
2023
2011
BUSH IAH
33
34
3
2
Hobby
28
14
1
0
Conroe
38
38
5
0
College Station
52
51
22
9
With the exception of Hobby Airport, 2011 and 2023 are nearly tied for the number of 100 degrees days up to 8-23. Hobby Airport has surpassed 2011 by 14 days.
More significant is the number of days at or above 105 with College Station crushing 2011 by 13 days. All sites have recorded more 105+ degree days in 2023 compared to 2011. The afternoon high temperatures have been higher in 2023 than in 2011 especially at Conroe and College Station.
Most of this has occurred in the last 3-4 weeks as the ground has dried and the influence of high dewpoints from the Gulf has become less. That has let afternoon temperatures spike higher compared to June and July.
By Jeff Lindner, Director Hydrologic Operations Division/Meteorologist, Harris County Flood Control District, on 8/23/2023
2185 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2023/08/Drought-Comparison.png?fit=1100%2C800&ssl=18001100adminadmin2023-08-23 18:55:102023-08-23 18:56:39Drought Comparison – 2011 to 2023
The massive $1.77 billion expansion of the 120-acre Northeast Water Purification Plant near Summerwood is now well into its last phase. The last update to the expansion website is dated May 23, 2023 and estimates completion in 2025. Contractors have made considerable progress since May. This satellite image is dated 6/14/23. Note the area on the far right at the eastern side of the plant. That area contains most of the new construction activity.
Landsat Photo in Google Earth from June 2023
Aerial Photos Taken 8/12/23
Compare the photos below of the Northeast Water Purification Plant taken just two months later. They were all taken on 8/12/23.
Looking SW from NE Corner of plant.Close up looking south.Wider shot looking N from SE corner of plant. White circle will contain a giant water storage tank.Looking W at entire plant. Note NE corner of Beltway 8 beyond plant and Atasocita Landfill in upper right.Looking ENEtoward Lake Houston
5X Capacity Increase Will Help Reduce Subsidence
The Northeast Water Purification Plant is designed to help ensure Houston’s water supply while reducing groundwater usage. Pumping groundwater at a rate greater than nature replaces it can cause irreversible subsidence. Subsidence has been linked to increased risk of flooding and structural damage.
The physical site above contains three major sections.
The original plant which can treat 80 million gallons per day (foreground)
First expansion phase (middle)
Second expansion phase (far end).
In May, Phase One was nearing completion and expected to be ready soon. Phase Two is the major focus of efforts now.
Because Lake Houston is so shallow, turbidity increases rapidly during rainfall events. Accordingly, the partners have incorporated both wet- and dry-weather technologies into the treatment plant, so operators can switch nimbly as needed.
Innovative treatment strategies like chlorine dioxide, ozonation and biological filtration have been proven at other Texas facilities using similar source waters. Given the broad range of raw water qualities, they will help the City preserve high-quality finished water and deliver more of it.
Majority of Water Used by Industry
Houston Public Works Drinking Water Operations (DWO) currently serves about 2.2 million people. And Harris County’s population alone is projected to expand to 5.5 million people by 2050. But serving all those extra people is only half the battle.
Many Sources Help Meet Demand, Protect from Drought
To meet demand DWO has three water treatment plants and 49 groundwater production facilities. They span four counties and 600 square miles, making Houston’s system one of the most complex in the nation.
And to feed those plants, the City of Houston owns a 70% share of Lake Livingston, a 70% share of Lake Conroe, 100% of Lake Houston and a 70% share of the future Allen’s Creek Reservoir on the Brazos River.
The variety of sources help sustain a growing population through droughts, such as the one we are in now. Corporations evaluate such factors when choosing where to expand. For more information about Houston’s water supply, check this informative history, written by Susan Smyer in 2008.
Posted by Bob Rehak on 8/22/2023
2184 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2023/08/20230812-RJR_2264.jpg?fit=1100%2C733&ssl=17331100adminadmin2023-08-22 11:50:102023-08-22 11:50:11Northeast Water Purification Plant Expansion Now in Last Phase
8/21/23 (9 AM CDT) – Three named storms have formed in the Atlantic in two days and we will likely get fourth (in the Gulf of Mexico) today or tomorrow.
Tropical storms Emily and Gert formed in the Atlantic yesterday (8/20/23). Gert formed overnight. And a fourth disturbance barreling across the Gulf of Mexico toward the lower Texas Coast could reach tropical storm intensity today or tomorrow, according to the National Hurricane Center (NHC).
2023 Summary Compared to 30-Year Average
So far this year, the Atlantic Basin has had:
An unnamed sub-tropical storm in January, that was later determined to have 70 mph max winds
Tropical Storms Arlene, Bret and Cindy in June
Hurricane Don in July
Emily, Franklin and Gert in August
If the disturbance currently in the Gulf turns into a named storm, it will become Harold – the ninth storm of the year to reach tropical storm intensity.
Normally, by this week in the hurricane season, the Atlantic Basin has five named storms. See the table below from the NHC’s Climatology page.
Progress of the average Atlantic season (1991-2020). Date upon which the following number of events would normally have occurred.
Number
Named systems
Hurricanes
Major Hurricanes
1
Jun 20
Aug 11
Sep 1
2
Jul 17
Aug 26
Sep 19
3
Aug 3
Sep 7
Oct 28
4
Aug 15
Sep 16
–
5
Aug 22
Sep 28
–
6
Aug 29
Oct 15
–
7
Sep 3
Nov 15
–
8
Sep 9
–
–
9
Sep 16
–
–
10
Sep 22
–
–
11
Oct 2
–
–
12
Oct 11
–
–
13
Oct 25
–
–
14
Nov 19
–
–
Greatest Threat to Houston is Fire
None of the current disturbances in the Gulf, Caribbean or Atlantic represent a threat to Houston.
The closest storm to Houston is south of Mississippi as of 9AM Tuesday morning. It will miss the upper Texas Coast and likely come ashore between Corpus Christi and Brownsville tomorrow.
NHC says that showers and thunderstorms are showing signs of organization and banding. Environmental conditions appear conducive for development. And a tropical depression or tropical storm is likely to form before it reaches the coastline on Tuesday. Formation chance is high…80 percent.
The greatest threat to the Houston area is not rain or flooding; north of I-10, we should see only about a tenth of an inch from the storm. But hot, dry conditions combined with a long-term drought have created critical fire weather conditions. A burn ban is in effect. High winds associated with the storm could spread fire quickly. So be careful. Several fires are already burning in other parts of East Texas.
Discussion of Other Disturbances
Unnamed Storm off African Coast
NHC gives the other unnamed storm off the coast of Africa a formation chance of 70% in the next 7 days.
Emily
Emily will also turn north. Its intensity will lessen into a tropical depression by Tuesday morning.
Franklin
NHC predicts Franklin will turn north and cross Puerto Rico, the Dominican Republic and Haiti through the middle of the week. It could produce heavy rainfall; life-threatening flash and urban flooding; and mudslides through Wednesday.
Gert
Gert is quickly unraveling. NHC expects to downgrade it into a tropical depression by Monday at 2PM.
A Record?
Is three or four named storms in two or three days a record? According to Harris County Meteorologist Jeff Lindner, it’s not. The record is closer to five or six at one time, he says. Regardless, tropical activity is heating up. The peak of hurricane season is still three weeks away – September 10th. It looks like earlier predictions of an above-average season were accurate.
In the meantime, watch out for that heat! Here’s a summary put together by Lindner of record highs on 8/20/23.
College Station: 112 (tied all time record high from 9-4-2000, broke the all-time August record high of 110 from 8-17-1903, and shattered the daily record high of 107)
BUSH IAH: 108 (broke the daily record high of 107 from 1909). This is only the 5th time since the 1880’s that Houston has reached 108. 1 degree shy of the all-time record high of 109.
Hobby: 107 (broke the daily record high of 101 in 1999).
Galveston: 97 (tied record high from 1995)
Huntsville: 112 (shattered the daily record high of 106 from 1909)
Madisonville: 108 (broke daily record high of 105 from 1948)
Sugar Land: 107 (broke daily record of 101 from 2018)
Conroe: 109 (tied all time record high from 2000 and 1925)
Tomball: 110 (shattered daily record of 101 from 1999) All time record high surpassing 108 in 2000
Wharton: 106 (broke daily record of 100 from 1911)
Brenham: 108 (broke daily record of 105 from 1948)
Posted by Bob Rehak on 8/21/23
2183 Days since Hurricane Harvey
https://i0.wp.com/reduceflooding.com/wp-content/uploads/2023/08/two_atl_7d0-3.png?fit=900%2C665&ssl=1665900adminadmin2023-08-21 08:46:472023-08-21 08:46:48Three Named Storms in Atlantic in Two Days, Could Get Fourth
Drought Comparison – 2011 to 2023
By Jeff Lindner, Harris County Flood Control District’s Director Hydrologic Operations Division/Meteorologist, with a few minor edits for a non-technical audience.
There have been many comparisons of this summer to that of 2011 with respect to the heat and drought. Below, see the comparison of drought, water supply storage, and heat between 2011 and 2023.
Rainfall (Jan 1 to Aug 23)
Rainfall departures in 2023 were tempered by a wet April and May over much of the area, while in 2011 drought conditions in the spring were some of the worst ever recorded with many areas recording their driest spring ever. 2011 was also preceded by dryness in late 2010 that helped to worsen the 2011 drought conditions and water supply concerns.
Rainfall at Hobby Airport in 2011 (Feb-May) was only 1.31 inches compared to 2023 of 11.85 inches.
While it is clear that 2011 was worse with respect to lack of rainfall, the abrupt change in rainfall from late spring into the summer of 2023 has “shocked” vegetation across the region.
Additionally, it has been hotter to some degree (especially overnight) in 2023 and the flash drought has been severe with nearly the entire area drought free in early June to all of the area in severe to extreme drought as of August 15th.
The very warm maximum temperatures and record “high” low temperatures over the region have resulted in rapid degradation of vegetation health. Tree losses were staggering in 2011 and the area is starting to see losses mounting in 2023, but far below what was experienced at this point in 2011.
Comparison of Drought Conditions, Extents
In 2011, exceptional drought covered most of the state.
In 2023, exceptional drought is minuscule by comparison.
Reservoir Storage
2011 also featured significant drawdown on area lakes and water supply reservoirs as the longer duration “hydrological” drought resulted in record or near record low inflows to several lakes.
As of this afternoon, statewide reservoir storage is at 69.8% of capacity compared to 65.4% on this date in 2011. A low of 58.5% was recorded on 11-18-2011.
The table below summarizes storage capacities for the first 2 weeks of August 2023 compared to 2011:
Lake Conroe and Houston are much better off than in 2011 with Lake Livingston being nearly the same and both Somerville and Texanna significantly better off in 2023 versus 2011. This matches well with the rainfall trends experienced in late Spring over the area which for the most part filled Houston, Conroe, Somerville, and Texanna to near capacity, allowing the recent dryness to be well handled.
This was not the case in 2011 when a very dry spring and dryness from late 2010 was already depleting capacities prior to the summer increased demand and evaporation losses.
Central Texas Lake Levels Lower in 2023
However, across central Texas at Travis and Buchanan, conditions are worse at this point than in 2011. Travis is 3.46 ft lower in 2023 than in 2011 and Buchanan is 0.45 ft lower.
Central Texas and the highland lakes chain have been in drought conditions since the summer of 2022 and rainfall this spring was not as significant in this area compared to coastal areas of the state and SE TX, so lake inflows have been very low and evaporation and demand maximized.
Heat Comparison
In addition to the drought conditions, it has been brutally hot. But how does 2023 compare to 2011 with respect to 100 degree or hotter afternoons? This is only part of the story of the heat of 2023, as overnight low temperatures have also been warm.
College Station has recorded 42 days with a morning low at or above 80 degrees, BUSH IAH 41, and Hobby 44. However, Galveston has recorded 64 days this summer at or above 80 degrees for a morning low.
With the exception of Hobby Airport, 2011 and 2023 are nearly tied for the number of 100 degrees days up to 8-23. Hobby Airport has surpassed 2011 by 14 days.
More significant is the number of days at or above 105 with College Station crushing 2011 by 13 days. All sites have recorded more 105+ degree days in 2023 compared to 2011. The afternoon high temperatures have been higher in 2023 than in 2011 especially at Conroe and College Station.
Most of this has occurred in the last 3-4 weeks as the ground has dried and the influence of high dewpoints from the Gulf has become less. That has let afternoon temperatures spike higher compared to June and July.
By Jeff Lindner, Director Hydrologic Operations Division/Meteorologist, Harris County Flood Control District, on 8/23/2023
2185 Days since Hurricane Harvey
Northeast Water Purification Plant Expansion Now in Last Phase
The massive $1.77 billion expansion of the 120-acre Northeast Water Purification Plant near Summerwood is now well into its last phase. The last update to the expansion website is dated May 23, 2023 and estimates completion in 2025. Contractors have made considerable progress since May. This satellite image is dated 6/14/23. Note the area on the far right at the eastern side of the plant. That area contains most of the new construction activity.
Aerial Photos Taken 8/12/23
Compare the photos below of the Northeast Water Purification Plant taken just two months later. They were all taken on 8/12/23.
5X Capacity Increase Will Help Reduce Subsidence
The Northeast Water Purification Plant is designed to help ensure Houston’s water supply while reducing groundwater usage. Pumping groundwater at a rate greater than nature replaces it can cause irreversible subsidence. Subsidence has been linked to increased risk of flooding and structural damage.
The physical site above contains three major sections.
In May, Phase One was nearing completion and expected to be ready soon. Phase Two is the major focus of efforts now.
Together the first and second expansions will produce 320 million gallons per day, bringing the total treatment capacity to 400 million gallons.
Plant Will Handle Wide Range of Turbidity
Because Lake Houston is so shallow, turbidity increases rapidly during rainfall events. Accordingly, the partners have incorporated both wet- and dry-weather technologies into the treatment plant, so operators can switch nimbly as needed.
Innovative treatment strategies like chlorine dioxide, ozonation and biological filtration have been proven at other Texas facilities using similar source waters. Given the broad range of raw water qualities, they will help the City preserve high-quality finished water and deliver more of it.
Majority of Water Used by Industry
Houston Public Works Drinking Water Operations (DWO) currently serves about 2.2 million people. And Harris County’s population alone is projected to expand to 5.5 million people by 2050. But serving all those extra people is only half the battle.
Many Sources Help Meet Demand, Protect from Drought
To meet demand DWO has three water treatment plants and 49 groundwater production facilities. They span four counties and 600 square miles, making Houston’s system one of the most complex in the nation.
And to feed those plants, the City of Houston owns a 70% share of Lake Livingston, a 70% share of Lake Conroe, 100% of Lake Houston and a 70% share of the future Allen’s Creek Reservoir on the Brazos River.
Lake Livingston supplies water to Lake Houston and the Northeast Water Purification Plant through the Luce Bayou Inter-Basin Transfer Project.
The variety of sources help sustain a growing population through droughts, such as the one we are in now. Corporations evaluate such factors when choosing where to expand. For more information about Houston’s water supply, check this informative history, written by Susan Smyer in 2008.
Posted by Bob Rehak on 8/22/2023
2184 Days since Hurricane Harvey
Three Named Storms in Atlantic in Two Days, Could Get Fourth
8/21/23 (9 AM CDT) – Three named storms have formed in the Atlantic in two days and we will likely get fourth (in the Gulf of Mexico) today or tomorrow.
Tropical storms Emily and Gert formed in the Atlantic yesterday (8/20/23). Gert formed overnight. And a fourth disturbance barreling across the Gulf of Mexico toward the lower Texas Coast could reach tropical storm intensity today or tomorrow, according to the National Hurricane Center (NHC).
2023 Summary Compared to 30-Year Average
So far this year, the Atlantic Basin has had:
If the disturbance currently in the Gulf turns into a named storm, it will become Harold – the ninth storm of the year to reach tropical storm intensity.
Normally, by this week in the hurricane season, the Atlantic Basin has five named storms. See the table below from the NHC’s Climatology page.
Date upon which the following number of events
would normally have occurred.
Greatest Threat to Houston is Fire
None of the current disturbances in the Gulf, Caribbean or Atlantic represent a threat to Houston.
The closest storm to Houston is south of Mississippi as of 9AM Tuesday morning. It will miss the upper Texas Coast and likely come ashore between Corpus Christi and Brownsville tomorrow.
NHC says that showers and thunderstorms are showing signs of organization and banding. Environmental conditions appear conducive for development. And a tropical depression or tropical storm is likely to form before it reaches the coastline on Tuesday. Formation chance is high…80 percent.
The greatest threat to the Houston area is not rain or flooding; north of I-10, we should see only about a tenth of an inch from the storm. But hot, dry conditions combined with a long-term drought have created critical fire weather conditions. A burn ban is in effect. High winds associated with the storm could spread fire quickly. So be careful. Several fires are already burning in other parts of East Texas.
Discussion of Other Disturbances
Unnamed Storm off African Coast
NHC gives the other unnamed storm off the coast of Africa a formation chance of 70% in the next 7 days.
Emily
Emily will also turn north. Its intensity will lessen into a tropical depression by Tuesday morning.
Franklin
NHC predicts Franklin will turn north and cross Puerto Rico, the Dominican Republic and Haiti through the middle of the week. It could produce heavy rainfall; life-threatening flash and urban flooding; and mudslides through Wednesday.
Gert
Gert is quickly unraveling. NHC expects to downgrade it into a tropical depression by Monday at 2PM.
A Record?
Is three or four named storms in two or three days a record? According to Harris County Meteorologist Jeff Lindner, it’s not. The record is closer to five or six at one time, he says. Regardless, tropical activity is heating up. The peak of hurricane season is still three weeks away – September 10th. It looks like earlier predictions of an above-average season were accurate.
In the meantime, watch out for that heat! Here’s a summary put together by Lindner of record highs on 8/20/23.
College Station: 112 (tied all time record high from 9-4-2000, broke the all-time August record high of 110 from 8-17-1903, and shattered the daily record high of 107)
Posted by Bob Rehak on 8/21/23
2183 Days since Hurricane Harvey