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At a Glance The threat of flash flooding is high in parts of southeast Texas, including Houston.

This is occurring on the one-year anniversary of the destructive Tax Day 2016 flood.

The threat of flash flooding is high in parts of southeast Texas, including the Houston metro area Tuesday, exactly one year after the infamous Tax Day Flood of 2016.

So far, the heaviest rain has most fallen south of Interstate 10 in southeast Texas, particularly over Galveston and Brazoria Counties.

(MORE: View National Interactive Radar Map)

Radar estimates rain rates from 2 to 3 inches per hour along a stalled band of rain in Brazoria and Galveston Counties. According to the National Weather Service, Santa Fe, Texas, in Galveston County, picked up 8.28 inches of rain in 12 hours through 9:15 a.m. CDT Tuesday.

Water was reported in several homes in the town, and eight roads were impassable, according to local law enforcement.

Flooding of side streets was also reported in the city of La Marque, about 35 miles southeast of downtown Houston. High water was reported on the southbound lanes of the Gulf Freeway, Interstate 45, near FM 519.

In Brazoria County, ABC13 Houston also reported flooding of homes in Danbury , prompting closing of schools due to flooded roads .

Thanks to deep moisture, a slow-moving upper-level disturbance, and rather light winds through the atmosphere, the threat of additional heavy rainfall will persist through at least Tuesday afternoon in southeast Texas before that upper disturbance finally slides sluggishly to the east.

Additional rainfall amounts of 3 to 6 inches are possible in these areas, with locally higher amounts where the heaviest rainbands stall.

Flooding of small creeks, roads, even low-lying homes, are possible. Never drive into flood water. A majority of flood-related deaths occur in vehicles .

Mid-April Déjà Vu?

This is all happening on the one-year anniversary of the Tax Day Flood, the most widespread Houston metro area flood since Tropical Storm Allison's record flood of June 2001.

(MORE: Is Houston America's Flood Capital? )

According to Houston-based energy meteorologist Matt Lanza, 8 to 24 inches of rain deluged the north and west sides of the metro area in 12 hours . About 240 billion gallons of water were dumped on Harris County alone , according to the Harris County Flood Control District’s summary.

Tax Day 2016 was the second wettest calendar day on record in the metro area - 9.92 inches at Bush Intercontinental Airport - dating to 1888. Cypress Creek in northwest Harris County crested over 9 inches above its Allison 2001 crest.

Over 1,000 homes and businesses were flooded and over 1,800 high water rescues were performed. Damage from this event was estimated at $2.7 billion, according to NOAA.

If that wasn't enough déjà vu, two years ago at least 65 homes were flooded in Houston, and heavy flooding swamped buildings at Sam Houston State University in Huntsville, Texas .

MORE ON WEATHER.COM: Houston Tax Day Flood 2016 (PHOTOS)