Harvey sets another all-time rainfall record for continental U.S.

Yesterday, we carried a story from the Texas State Climatologist on a new 3-day rainfall record being set in Houston. Today, another record fell. Tuesday afternoon, the National Weather Service (NWS) announced that a gauge in Cedar Bayou, anear Mont Belvieu, Texas, recorded a preliminary rainfall of 51.88 inches.

NOAA’s NCEP, shows in data that we have an all time new record of 51.88″ at CEDAR BAYOU in Texas. The wettest tropical cyclone record still belongs to Hurricane Hiki, which developed off the coast of Hawaii in August 1950 and dropped 52 inches of rain. With rain still coming down in Texas, that value is surely to be broken

From NASA Goddard:

As Harvey continues to dump catastrophic rains over southeastern Texas and southwestern Louisiana, NASA has been tallying rainfall accumulations in the storm’s wake.

Total rainfall estimates from NASA’s Integrated Multi-satellitE Retrievals for GPM (IMERG) data were compiled for the period from August 23 to 29, 2017. During this period Harvey dropped heavy rainfall as it moved through the Gulf of Mexico and stalled over Texas. The IMERG totals showed over 30 inches of rainfall had occurred in the Houston metro area and part of the western Gulf of Mexico.

IMERG data for Harvey were compiled for the period from August 23 to 29, 2017 as it moved through the Gulf of Mexico and stalled over Texas. The IMERG totals showed over 30 inches of rainfall had occurred in the Houston metro area and part of the western Gulf of Mexico.

CREDIT

Credits: NASA JAXA, Hal Pierce

It has been reported that Harvey dropped over 40 inches (1016 mm) of rain over southeastern Texas during this period. IMERG Data are produced at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, using data from the satellites in the Global Precipitation Measurement mission or GPM Constellation, and is calibrated with measurements from the GPM Core Observatory as well as rain gauge networks around the world.

The National Weather Service reported at 1 p.m. CDT on Aug. 29 “A preliminary report from one Texas rain gauge has broken the Texas tropical cyclone rainfall record. Southeast of Houston, Mary’s Creek at Winding Road reported 49.32 inches as of 9 a.m. CDT. This total is higher than the previous record of 48 inches set during tropical cyclone Amelia of 1978 at Medina, Texas.”

The National Hurricane Center (NHC) indicates that Harvey continues to drop heavy rain over southeastern Texas and southern Louisiana as it moves toward the north-northeast.

Warnings and Watches in Effect as of 1 p.m. CDT, Aug. 29

The NHC said a Tropical Storm Warning is in effect from nNorth of Port O’Connor, Texas to Morgan City, Louisiana. A Tropical Storm Watch is in effect from east of Morgan City to Grand Isle, Louisiana. A Storm Surge Watch is in effect from Port Bolivar, Texas to Morgan City.

More Heavy Rainfall Expected

NHC forecasters noted that catastrophic and life-threatening flooding continues in southeastern Texas and portions of southwestern Louisiana. Harvey is expected to produce additional rainfall accumulations of 6 to 12 inches through Friday over parts of the upper Texas coast into southwestern Louisiana.

Isolated storm totals may reach 50 inches over the upper Texas coast, including the Houston/Galveston metropolitan area. These rains are currently producing catastrophic and life-threatening flooding over large portions of southeastern Texas and southwestern Louisiana.

Elsewhere, Harvey is expected to produce additional rainfall amounts of 5 to 10 inches across portions of southern Louisiana into coastal Mississippi and Alabama. Rainfall associated with Harvey will spread north by mid to late week, with rainfall amounts of 4 to 8 inches spreading into portions of Arkansas and the Tennessee Valley.

A list of rainfall observations compiled by the NOAA Weather Prediction Center can be found at: http://www.wpc.ncep.noaa.gov/discussions/nfdscc1.html

Winds, Storm Surge, Ocean Swells

Tropical storm conditions are occurring over portions of the warning area along the coast and are likely to persist during the next day or so.

The combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. The water is expected to reach the following heights above ground if the peak surge occurs at the time of high tide…

San Luis Pass to Morgan City including Galveston Bay…1 to 3 ft

The deepest water will occur along the immediate coast near the area of onshore winds. Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances.

Swells generated by Harvey are still affecting the coasts of Texas and Louisiana. These swells are likely to cause life-threatening surf and rip current conditions.

Harvey’s Location at 1 p.m. CDT, Aug. 29

At 1 p.m. CDT (1800 UTC), the center of Tropical Storm Harvey was located near 28.8 degrees north latitude and 94.3 degrees west longitude. That’s about 80 miles (130 km) south-southwest of Port Arthur, Texas and about 95 miles (155 km) southwest of Cameron, Louisiana. Harvey was moving a little faster toward the north-northeast near 8 mph (13 kph), and this general motion is expected to continue today and tomorrow, Aug. 30. On the forecast track, the center of Harvey is expected to move inland over the northwestern Gulf within the tropical storm warning area later tonight or early Wednesday.

Maximum sustained winds remain near 45 mph (75 kph) with higher gusts. NHC said no significant change in strength is expected before the center moves inland. A gradual weakening should begin thereafter. The estimated minimum central pressure is 997 millibars.

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For updated forecasts and warnings, visit: http://www.nhc.noaa.gov.

For local warnings and watches, visit: http://www.weather.gov.

By Rob Gutro / Hal Pierce
NASA’s Goddard Space Flight Center

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63 thoughts on “Harvey sets another all-time rainfall record for continental U.S.

    • The models have it moving off from Houston now. Some parts of Louisiana will get over 10 inches over the next day but at least Houston’s rain is over.

      • I posted the following several days ago, just before Harvey hit Houston:

        “If Harvey stalls, much flooding will result – many cities in Texas are so flat that flooding is a common occurrence. When I lived in Houston (circa 1997-98), we had several floods in the year, just from normal seasonal rainstorms.”

        I deeply regret the severe flooding and the suffering of the good people of Houston, and wish them the very best of good fortune in their recovery.

        In 2013, southern Alberta experienced the most costly natural disaster in Canadian history, when a major rainfall event caused severe flooding along all our rivers and inundated downtown Calgary and many suburbs and towns. I lived in the Mission community on the Elbow River, and our condo building was flooded, but we were fortunate – only the three parkade levels were flooded and the lobby and living levels were untouched.

        We were out of our building for a month, and stayed with kind friends. When we returned, my five-year-old daughter and I were charged with turning on the power to each apartment as the residents returned – we did about half of the ~110 units in the building. This was necessary because all the fridges were cleaned out and left open to air, and the power shut off in each unit to prevent the fridge motors from burning out. The elevators and emergency stairwell and hallway lighting were all shut down, because some genius had located all electrical services in the basement, which had flooded. I bought my daughter a battery-powered headlamp, which she wore with pride, and we walked up interminable unlit flights of stairs in our 17-story building, locating and mapping the byzantine electrical switch box locations for each unit, and restoring power as the owners returned.

        My friends who lived along the river were not so fortunate – many homes were flooded above the ground floor, although few second floors were inundated. Some people were out of their homes for a year or more, during reconstruction. The city has now essentially recovered, although a few flood-relics remain.

        In general, the flood recovery was a great success, although it was made worse by foolish and highly selective Alberta government buy-out policies.

        The assistance of tens of thousands of volunteers was remarkable – complete strangers helped clean out basements of mud and flood-damaged drywall and insulation, and many homes were drying out and ready to restore within days – this is critical to prevent mold buildup. In Mission, a gentleman of East-Indian descent who ran a flagworks company took charge and organized thousands of volunteers via social media. He loaned us a giant oilfield pump truck, donated by a company in Edmonton, and we used it to pump out our parkade.

        I was asked late one night by my Member of Parliament (MP) Joan Crockett to line up some houses for cleanup the next morning. I drove over to George’s house at 11pm and found him standing in mud in a window well, as his friends passed him buckets of mud from his basement and he poured them over his silt-filled back yard. He agreed to accept the help, as long as there were no TV cameras, etc.

        The next morning we all met at George’s – my friend Joan, a few other MP’s including Dr. Kellie Leitch, Prime Minister Steven Harper’s wife Laureen and a few others. We finished cleaning out George’s basement – removing all the mud and wet insulation – and there were no TV cameras – just one group snapshot that I recall. We then moved on to clean several other houses, and did about four homes in total by the end of the day. The group then moved south to work at High River, the community hardest-hit by the floods (Note to file: Do not build a town in a place called High River).

        There was no looting that I know of, and the volunteer effort was remarkable.

        So Houston has a few years of rebuilding ahead, and you will arise stronger than before. Houston is full of kind, decent people – again, I wish you well.

        Best, Allan

        Allan MacRae, P.Eng., Calgary

  1. Pretty terrible for those in the floods – or with family there. My thoughts are with them.

    Might I ask how lengthy is the rainfall record in Texas?
    And in the areas setting instrumental records?

    Again – terrible weather; but is it conceivable that similar storms have dumped as much rain in the past?
    Ahh – not the past 150-200 years, but in the past 10 or 12thousand years.
    At least once? Do we know?

    Probably not.

    Auto

    • Of course they have. Stalled systems are not rare. Mother earth has a whole litany of extreme weather she can throw at us.

    • Pretty sure the all-time 24 hour record is still held by Alvin, TX during T.S. Claudette 1979.
      Forty-Two inches. That’s right – 42 in. during 24 hr.
      That would be near a record rainfall for the entire rainy season here in the Puget Sound area. We broke a record just this last year over several months of cold rainy misery….

  2. Having been through more than several tropical cyclones at this point in my life my heart and prayers go out to the people of Houston and coastal Texas. They did indeed get one heck of a lot of rain though not the devastating wind and storm surge of say the Galveston, 1990 hurricane. Sure the record for rainfall was broken but we are not talking about feet but a few inches. Having spent most of my life in Florida I seen days where it can rain half an inch literally across or down the street and not rain at all at my house. Meaning rain gauges if in other places might have recorded less rainfall or much more rainfall. Sadly the news media has little historical perspective and are playing out their long held agenda. Their “favorite” hurricane will always be Katrina which they happily beat over the head of Bush but not the Mayor or Governor. For several years before Katrina, I served on a interstate commission. For several years we were briefed on New Orleans and what would happened if the city took a major hit. Most people do not know that the flooding in New Orleans would have been prevented if storm gates on Lake Pontchartrain had been built but instead were stopped by environmentalists and a federal judge.

      • Fact – the storm gates were prevented from being built (by environmentalist lawsuit and a federal judge? appeal?) Conjecture: If the storm gates had been built when and where they were proposed they would / might have / would not likely have – changed the outcome of the Katrina flooding.

      • NW, gates at the lake would have prevented the storm surge from coming into the outflow canals. As well, they would have constituted a barrier between the lake and the canals. So, even if the canal walls had been breached, only the water from inside the canals would have emptied into the city and not the entire lake. (edwin is correct)…

      • Ralph, i was unaware of what edwin was referring to, so thanks. The solution is actually much simpler than that. All that was needed were gates and barriers at the mouths of the outflow canals where they meet the lake. (this was a well known design flaw) Since katrina, this has been done. Pumps are also placed at the mouths of the canals where they pump water from the canals, over the barriers and into the lake. Had this been in place, as it originally should have been, katrina would have been a ‘betsy’ like footnote in new orleans history…

  3. It is both possible that the worst in the Houston /Gslviston region is over, and that the worst ever rainfall records including Hawaii have been set. Until the data is collected and QC’d, dunno.

  4. As I read the article a cartoon image came into my head, of Michael Mann standing in the pouring rain, urinating into a rain gauge and saying ‘unprecedented’….

  5. Here is a reply to an email asking about how my old former next door neighbor fared in all the hoopla. Very few houses were placed near the bayou before subdivision construction
    took off after WWII. The people back then built houses individually and not in wholesale lots. His remark about improvements is aimed at curbs and gutters with underground pipes drainage. In his neighborhood there are open ditches. When these fill the water and flood over the surface in a heavy rain the water can be seen flowing sheet wise toward the bayou. The slope is gradual, so it takes time. The location is only 5.8 miles from the now famous Flood Control District rain gauge setting the national record rain fall for three days. Other gauges in the area also did well.

    “Bob, we are doing okay and so is your old house. Since the street and drainage has not been upgraded , we are not flooding. My back yard gets full of water at the back fence like always when it rains hard. Then the rain slows and it drains off. Only problem I have is I am getting cabin fever, as they call it. We are to leave on labor day on a trip. Harvey has been keeping me from getting ready. Instead of slowing getting ready over a number of days. I will be doing a lot more at the end of the week and week end. Plus right now it is flooded all around. So you can’t go any where with out being stopped with high water. The rain stopped for a real short time today and Delores took the dogs walking since they have not been out any. She said that there has been a fence erected across the road at Cedar Bayou Junior High so no one would go down to Ferry Road which is flooded. Cedar Bayou has come up and done a number on housing additions built next to it. Channel 13 has one of their people here in Baytown in Pinehurst and Whispering Pines subdivision covering all the people being taken to safety by boat. I am sure glad I live in a house built in 1950 and in a subdivision that the streets and drainage has not be upgraded any. So I can
    watch this on TV instead of in a flat bottom boat.”

    • I’d hardly call that “ugrading”. Upgrading building standards almost always means lots of increased covered ground, very limited retention ponds or open land, and storm sewers that all empty into the exact same streams.

      You’ really luck. It sounds like 1″ of water has miles and miles to spread over.

  6. From Wikipedia
    . Tropical Storm Claudette holds the national 24-hour rainfall record, with 42 in (1,100 mm) observed within such a timeframe. Taking place only one year apart, in 1978 and 1979, Amelia and Claudette are also among the wettest tropical cyclones on record to have occurred in Texas.
    The SST in the Gulf of Mexico was not unusually warm compared to the 21st C.

  7. I monitor the high resolution AVHRR data, that you can see in detail in WebGL here. The Gulf was warm, but not exceptionally so, previously, as in this view from 15 August:

    It is interesting to see the cooling effect that Harvey then had:

    There isn’t much change by Aug 24th, when it ws reaching hurricane status. On 25th, there is a small cool spot (still the same on 26th). But by 27th it had grown, and by 28th (most recent data) even more, though some cooling showed in the earlier part of its path too.

  8. Although not reported in the media as far as I know, Active duty Marines from North Carolina are being sent to Texas to help out. My Grandson has advised us they are leaving to go there tomorrow.
    No sure what their mission will be. Maybe a backup for the National Guard.

    • I am guessing they will have some ‘policing’ duty; insuring the domestic tranquility. This will be a long duration event. There is still a tremendous amount of water uphill from Houston that will slowly be working its way to the Gulf of Mexico. It is quite possible that areas that have not flooded yet, will start to flood days from now. In Florida, we called this ‘sheet flow’, and it can take a long time to go away.

      The combination of empty neighborhoods, full shelters, road problems and diminishing patience from everyone, will create a huge demand for law enforcement, especially as the days go into weeks and the weeks go into months. The stress on this area is only just beginning.

  9. About 35″ fell in my yard during the storm. Spent this afternoon canoeing to my son’s fiance’s house with a care package. Going back tomorrow to remove the flooring and base mold.

  10. Why do the Acronyms like NOAA, NASA, NWS spend time reporting records? Is there anyone who actually benefits from the knowledge? Is the Acronym effort commensurable with any benefit it brings?
    In theory, I can create higher rainfall records in a district by deploying many more rain gauges. One of them will beat the others and the average. I’ll bet there are more rain gauges around Houston than there were 20 years ago, so comparison with past records is false.
    It is called cherry picking. Shame on the Acronyms for doing it. Geoff

    • “so comparison with past records is false.”

      maybe false.

      you dont have information that you dont have

      • “you dont have information that you dont have”

        That’s never stopped you though has it, Mosher?

        I must say also that for someone who claims to have an English qualification, your level of literacy is positively atrocious.

  11. Regarding these dams which are overflowing. Did they anticipate the storm and let out excess water early, or did they try and save it because – like for Brisbane in 2011 – they had a “never-ending” drought?

    • Addicks and Barker reservoirs are flood control structures. They normally store minimal amounts of water. Most of the land is either wild or used for parks and ball fields. When the reservoirs fill up, all those facilities are underwater. For example, before the hurricane, Barker reservoir had less than 5000 acre-feet of water, currently at approximately 169000 acre-feet, and dropping.

  12. Funny question but how do you even measure that much rain in such a short time? Industrial strength tipping rain gauge? Measure and empty your manual gauge every 30 minutes or so? Someone must have put in quite an effort keeping up…..

  13. Of course this is due to climate change.

    Look at the scale and impact of this… something new and off the charts for Texas.
    The chances of it being purely down to natural variation are small.

    This is exactly what you’d expect to see as a result of warming.

    This is exactly what the ‘alarmists’ have been telling you was coming.

    And it will happen again within the next decade.

    • griff this is exactly what happens when you biuld all kinds of stuff except decent levees :)
      Houston has no decent levee system while it should. That’s a little fact our belgian media did report.

      oh and a stalling storm is just weather my boy that will happen all the time once in a while :)

    • Griff: “this is exactly what you’d expect to see as a result of warming.

      This is exactly what the ‘alarmists’ have been telling you was coming.

      And it will happen again within the next decade.”

      That’s funny, Griff. The Alarmists said that after Katrina we were going to see bigger and *more frequent* hurricanes in the future because of CAGW. Yet we went from 2005 until now before a major hurricane hit the U.S. (unless you go by Joe Bastardi’s scale which shortens the timeframe a couple of years), so obviously the “more frequent” claim of Alarmists is wrong, and according to you, will continue to be wrong if another strong hurricane is a decade away.

      It’s been a long major hurricane drought for the Alarmists and CAGW, and they are going to try to milk Hurricane Harvey for all its worth.

      There’s nothing unusual about Harvey. There were stronger storms in the past that dropped more rain and they had nothing to do with CAGW.

      Griff is grasping at straws trying to connect Hurricane Harvey to human-caused global warming/climate change.

      No evidence, Griff. No evidence.

      • what’s more funny about griffs remark, is that in every year on worldwide level you got tropical cyclones showing the same path behavior as Harvey does: stalling, making loops, having an unusual track,….

        odd is
        when it happens over the open ocean: “nobody cares”
        when it happens over land or it makes landfall: “Mann made global warming!!!!”

        just hilarious :)

    • Griff is so predictable. So you find it odd that a city built on a historic flood plain with a river running through it flooded as a result of a hurricane Griff?

      • i find it more odd that they didn’t build any type of decent levee system… Even New Orleans has a better levee system then Houston has….

  14. I thought this was very interesting, and if true it no doubt explains a lot of the “record rainfall” aspect of this storm. The idea sounds plausible enough but I believe it’s the first time I’ve ever seen anything like this stated in print.

    https://www.scientificamerican.com/article/hurricane-harvey-why-is-it-so-extreme

    How can Harvey produce such extreme rainfall even though it is no longer over the ocean?

    The answer to this is fascinating. Normally a hurricane pulls moisture up from the ocean and releases it as rain all around the storm’s area, particularly in the northeastern quadrant. But Harvey has dropped so much water over such a large area of southeastern Texas that the storm is pulling that water back up into itself and dumping it again as more rain. The flood area is so far and wide that it is acting like part of an ocean, feeding warm moisture up into Harvey. “You only need about 50 percent of the land to be covered with water for that to happen,” Masters says. “Obviously we have more than that in Texas.”

    • “But Harvey has dropped so much water over such a large area of southeastern Texas that the storm is pulling that water back up into itself and dumping it again as more rain. The flood area is so far and wide that it is acting like part of an ocean, feeding warm moisture up into Harvey.”

      That is interesting.

      Joe Bastardi said the trough that was blocking Hurricane Harvey from moving inland would also enhance wind development within Harvey.

      • that’s true it’s why hurricane Wilma did restrengthen over Florida. It crossed the everglades and barely weakened because of it

        Also Harvey was near enough to the coast to slingshot moisture in. there are a few hurricanes tropical storms that did the same: hurricane Mitch, TS Allison (that did drown houston, describing an near identical path and loop) TS Amelia in 1978 it just stalled and poured down a bit more inland dropping 48 inches that one litterally rained out till it dissipated…

        hurricane Flora in 1963 did the same with cuba: a 4 day loop over the island dumping… the double of Harvey over them.

        can it be worse? yes ways worse: in 1980 the wettest tropical cyclone did struck Reunion island: it made 1 loop over the island, a second one to the northwest of the island, then returned so Reunion stayed 15 consecutive days in it’s rainbands and core. That’s tropical cyclone Hyiacinth and it’s record is almost five times the rain that fell on Houston it dumped 239.5 inches of rain destroying half of the island yes half an inch inch short of 20 feet of rain.

        in perspective that’s an equivalent of a 2 storey building of rainwater per square meter

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