Rainfall Roulette
9/2/26 at 4 PM – Tropical Storm Edouard to date has resembled a game of rainfall roulette for weather forecasters. Slight shifts in direction have made orders-of-magnitude differences in predicted precipitation.
Forecasters had predicted the narrow storm would hit eastern Harris County. However, it angled more north and created catastrophic flooding in Hardin County instead. Hardin lies immediately to the east of Liberty County.
Orders of Magnitude Differences Just Miles Apart
Gages in the Lake Houston Area recorded .08 inches for the last two days. Yes! Less than one tenth of an inch.
However, eastern Hardin County received 27.5 inches of rain – last night alone.
According to Harris County meteorologist Jeff Lindner, flooding continues in eastern Liberty County, Polk County, Tyler County, and Hardin County after very heavy rainfall this morning.
Doppler radar estimates from Lake Charles show a maximum of 25-28 inches over eastern Hardin County into southern Tyler County. Tyler lies immediately north of Hardin.
A Jefferson County Drainage District #6 rain gage in western Hardin County recorded 12.35 inches of rainfall in 6 hours this morning and a 24-hour total of 17.75 inches.
Uncertainty Remains
South of Edouard, clouds have been decreasing and the air mass is warming. With afternoon heating, Lindner expects the tropical air mass to begin banding again, especially on the southern side.
According to Lindner, that could affect portions of Waller, Montgomery, Harris, Liberty, San Jacinto, and Polk Counties. Westerly flow from the circulation could bump into the southerly flow returning from the Gulf and possibly a weak sea breeze.
Lindner believes that, given the highly tropical air mass in place, hourly rainfall rates of 2-3 inches will be possible. And if this falls over areas that have already experienced significant rainfall in the last 24 hours, additional flash flooding is likely.
However, areas that have received little rainfall so far will have minimal flood risk, although some street flooding is possible. Most storm sewers can handle an inch per hour. So when rainfall rates exceed that, water can back up into streets.
Dealing with Uncertainty
The location of any additional bands remains uncertain. But models suggest banding over northern Waller and southern Montgomery Counties that sinks into portions of northern Harris County later this afternoon and evening. See predicted rainfall below for the 12 hours from Wednesday 7 pm to Thursday 7 am.
For the Lake Houston Area, Edouard was a close call. But it illustrates the need to prepare. The Harris County Flood Control District and City of Houston must accelerate their flood-mitigation activities in this area. We’ve waited long enough.
The Lake Houston Area suffered the worst flooding in Harris County during Harvey. But it has received little flood-mitigation help to date.
As of January 2026
Nine years after Harvey, we need to start building the flood-mitigation projects promised long ago. We can’t afford to keep betting on rainfall roulette.
This is an election year. If not now, when?
Posted by Bob Rehak on 9/2/26
3291 Days since Hurricane Harvey
