A Breather: Rain Mainly South of I-10 For Most of Day

Today, the Lake Houston Area may finally get a breather from non-stop storms that blanketed the area for the previous three days. That doesn’t mean that we won’t get more rain. And it doesn’t mean flooding is not possible. It just means streams and bayous may get a chance to drain.

According to Jeff Lindner, Harris County Meteorologist, “Light rainfall continues mainly south of I-10 across the area.”

RadarScope Pro as of 10:54AM Houston time shows a large complex of storms to Houston’s south and west. They are moving north but have been dissipating as they move past the I-10 corridor for most of the morning.

Says Lindner, “A complex of thunderstorms is moving well into the NW Gulf. Another moving offshore of south Texas will likely keep southeast Texas stable today with only passing light or moderate rain showers and those will mainly focus south of I-10. Additional showers and thunderstorms will be possible on Thursday and Friday with continued high moisture levels over the area. However, the activity looks more scattered in nature and not as organized or intense as the last 48 hours.”

Additional rainfall amounts of 1-3 inches can be expected over the next 48 hours with the higher totals likely focused south of I-10.
Jeff Lindner, Harris County Meteorologist

Rainfall In This Event Almost Half of Year’s Total So Far

My digital rain gage indicates that we’ve received almost as much rain in the last three and a half days as we have year to date. That’s 138 days.

Here’s a breakdown:

Year to date: 23.64 inches
March: 1.95 inches
April: 4.01 inches
May to date: 11.38 inches
May 16: 1.22
May 17: 5.57
May 18: 1.64
May 19 so far: 1.22

According to the National Weather Service, the normal cumulative precipitation for May (up to the 19th) is 3.12 inches. And the normal yearly precipitation through today is 16.42 inches. Before this is all over, we could skew those averages a bit. We’ve exceeded the monthly average to date by a factor of two in the last two days!

*Two-day rainfall totals for most Harris County gages as of 5/19/2021 at 10AM.*

Run-off

Run-off continues from the rainfall over the last 48 hours with widespread totals of 3-5 inches over much of the area and an isolated amount of 8.56 inches in the Huffman area. Here’s how that is affecting local rivers and streams.

Rivers and Stream

Creeks in the northwestern portion of Harris County remain elevated and in some cases near bankfull. So do the middle and upper portions of Cedar Bayou and the West and East Forks of the San Jacinto River. Creeks in the northwestern portion of Harris County will crest and slowly fall this afternoon while rises will continue along the West and East Forks of the San Jacinto River. Peach Creek at 2090 is flooding.

From Harris County Flood Warning System at 10am 5/19/2021

*East Fork at New Caney should experience minor to moderate flooding in next five days.*

*West Fork at 59 should experience minor flooding in low lying areas by Saturday.*

*Peach Creek at FM290 is already out of its banks according to the Harris County Flood Warning System.* *As of 11 am, elevation was 99.1. A ten-year flood at this gage is 99.3.*

Lake Report

Lake Conroe is at 201.64 feet (normal is 201) at this writing and and releasing 2,665 cubic feet per second. Notice that they no longer have a box for seasonal lowering. They now call that COH (City of Houston) Diversion. It’s not that they have discontinued the seasonal lowering; they’ve just changed the way they account for it, according to Jace Houston, SJRA’s general manager. When the Lake is above 201 and water is inbound as it is now, SJRA is allowed to release water without it coming from the City of Houston’s portion.

When the flood threat has passed, if and when the City calls to resume seasonal lowering, the rate will show up in the COH diversion box. SJRA seems to be trying to lay responsibility for any inconvenience to Lake Conroe boaters at the feet of the City of Houston, which has already been dismissed from the Lake Conroe Association lawsuit.

Meanwhile, Lake Houston is up about a quarter foot so far this morning, despite the flood gates being wide open.

*How Lake Houston Levels have varied during the last 7 days. Graph shows up to noon on 5/19.*

If rain during the rest of today remains light, SJRA may be able to avoid flooding people upstream and downstream, just as they did on May 1st, when the areas upstream from Lake Conroe received 8-10 inches of rain.

Flash Flood Watch Remains in Effect Through Thursday Morning

In the meantime, a flash flood watch remains in effect for the Houston region through tomorrow morning. Chance of precipitation is 60% this afternoon, going up to 90% this evening. NWS predicts up to 1.25 inches of rain today and up to .75 tomorrow for the Kingwood area.

As of this morning, here’s how White Oak Creek looks from the back yard of Woodstream Forest resident.

*Photo from a video courtesy of Donald and Kristi Brown. Taken on 5/19/2021*.

Posted by Bob Rehak on 5/19/2021 at Noon based on information from the NWS, HCFCD, Coastal Water Authority and SJRA

1359 Days since Hurricane Harvey

Rainfall In This Event Almost Half of Year’s Total So Far

Run-off

Rivers and Stream

Lake Report

Flash Flood Watch Remains in Effect Through Thursday Morning

You might also like