At least two tornadoes have been confirmed on the northwest side of Houston from Monday’s storms

In brief: A high-end EF-1 and a low-end EF-2 tornado were confirmed today from damage surveys conducted by the National Weather Service northwest of Houston. The first occurred in Riata Ranch. The second was in Klein. Additional damage surveys may still be done to check for other tornadoes or to fine tune these paths.

Preliminary tornado confirmations from Monday. (NWS Houston)

Two confirmed tornadoes

The NWS Houston office went out and did the dirty work on damage surveys from Monday’s tornadoes. They confirmed two so far. The first was a high-end EF-1 that had maximum winds of 105 mph (corrected from the above graphic) in Riata Ranch and a path length of 2.6 miles. The second was a low-end EF-2 that hit the Klein area, with maximum winds of 115 mph (corrected from the above graphic) and a path length of 3.8 miles. I believe these are the first tornadoes in Harris County since just after last Christmas.

Riata Ranch tornado

The Riata Ranch tornado touched down just after 1:20 PM on Monday. For those unfamiliar, Riata Ranch is just east of Barker Cypress Road just south of 290. A radar capture from 1:23 PM on Monday shows the tornado developing. The first touchdown point occurred in Towne Lake, just off Tuckerton west of Barker Cypress.

Radar capture from 1:23 PM on Monday, when the tornado initially touched down in Towne Lake, just southwest of Riata Ranch. (RadarScope)

Following radar, you are able to see the rotation track to just west of Barker Cypress at 290 by 1:26 PM. It seems that a debris signature (TDS) becomes evident on radar between 1:26-1:29 PM, which indicates a pretty healthy tornado in progress. This occurs as the original circulation begins to broaden out crossing 290. At this point, the tornado was lifting.

Tornadic debris signature showing on radar at 1:29 PM indicating a confirmed tornado. Meanwhile, the tornado was actually dissipating at this point. (RadarScope)

Indeed, the NWS found that the tornado dissipated around 1:28 PM at 290 and Barker Cypress.

Overall, the TDS on this one was very impressive, usually only the type of TDS I’ve seen in typically stronger tornadoes. This is likely indicative of the densely populated area it struck.

Klein tornado

We got a 10-to-15-minute break before the same supercell dropped another tornado. Around 1:41 PM, a new tornado dropped just east of Cutton Road along Louetta Road.

The Klein tornado tracked from just east of 249 to just north of Spring Cypress and Stuebner Airline Road. (RadarScope)

This one did not show quite as strong a TDS as the Riata Ranch tornado, despite being a little stronger. Nuance is a thing. It didn’t take long for it to show up, however, which happened around 1:47 PM. Notably, the debris signature from the Riata Ranch tornado does not appear to have dissipated entirely around this time, but it does show up nicely.

A fairly sharp TDS was evident on the Klein tornado as well, maybe just a smidge less impressive than the Riata Ranch one. (RadarScope)

Notably, when you’re looking at these tornadic debris signatures, remember a radar beam doesn’t go out flat. It aims up, so at this distance, about 49 miles from the HGX radar in League City/Dickinson, we’re sampling what’s occurring about 3,500 feet up. So this indicates that the tornado was lofting debris several thousand feet up in the atmosphere. Overall, this was a very impressive event for Houston. We see tornadoes rather frequently here, but not usually this strong. Of the 78 tornadoes confirmed in Harris County since 2000, only 6 have been F/EF-2 or stronger. The Klein tornado now makes seven.