Houston derecho

Bo Adams

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Downtown Houston looked like it got hammered by wind mostly straight Line wind. I thought there was a possible spin up in cypress Tx. Was anyone in the area when it happened and what was your thoughts on it derecho accurate or was it a microburst? Just curious if there more then one opinion and why you feel that way.
 
EDITED: See several posts down for updated commentary
Well, it definitely was not a derecho considering the length and swath width requirements for such an event. This was a single substantial embedded supercell in an otherwise only marginally severe squall line. Definitely not a derecho.
 
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By definition it is considered a derecho if the swath of wind damage extends at least 400 miles (about 650 kilometers), is at least 60 miles (about 100 km) wide, includes wind gusts of at least 58 mph (93 km/h) along most of its length, and also includes several, well-separated 75 mph (121 km/h) or greater gusts,
To expand on Mr. Duda's comment. This is from the NWS Wichita page on the event that occurred in KS on the 19th.
 
Well, it definitely was not a derecho considering the length and swath width requirements for such an event. This was a single substantial embedded supercell in an otherwise only marginally severe squall line. Definitely not a derecho.
I wonder if it was appended to the damage swath that started NE of HOU over far sern TX b/c that could be tracked all the way to Apalachicola Fl, but does it meet the 400 mi in length? Part of it was over the GOMEX. But I agree, the HOU event was not a derecho. A discrete supercell embedded in a squall line with the RFD winds perhaps enhanced by the gust front of the squall line itself?

Did WFO HGX actually call it a derecho? I don't see any summary in their home page for the event.
 
This tweet is the most official sounding word from NWS HGX:
However, it seems other NOAA agencies are going ahead and just calling it a derecho, such as the NOAA Satellites page:
I think you have the right idea, Boris - whether the Houston wind swath gets lumped in with the wind report from further north and east. If it does, then the event could be argued to be a derecho (although the separation between measured sig wind gusts is pretty high, so I don't think it would be an easy argument).
 
Well, it definitely was not a derecho considering the length and swath width requirements for such an event. This was a single substantial embedded supercell in an otherwise only marginally severe squall line. Definitely not a derecho.
Thank you that’s what I thought I just kept seeing it on different sites and news outlets.
 
Thanks for elaborating as well.
By definition it is considered a derecho if the swath of wind damage extends at least 400 miles (about 650 kilometers), is at least 60 miles (about 100 km) wide, includes wind gusts of at least 58 mph (93 km/h) along most of its length, and also includes several, well-separated 75 mph (121 km/h) or greater gusts,

To expand on Mr. Duda's comment. This is from the NWS Wichita page on the event that occurred in KS on the 19th.
 
Well according to John's post, I am incorrect. And to some extent, I'll back off on my prior statement sounding so definitive. I no longer will claim that this was 100% not a derecho.

However, I think this case offers a semantics debate as well as a debate on whether the particular damage occurring in Houston was meteorologically associated with the convection that produced the higher wind reports in S LA, which I think it's reasonable to argue that it was. However, it also remains true that the winds and damage were pretty isolated to Houston proper in that area of the MCS and I think it is possible to outline separate tracks of severe wind reports within the larger MCS. Also, if you look at just the measured wind gusts, there is substantial separation between clusters of them (see below), and there was only 3 or 4 actual measured sig wind reports. This, to me, does not quite measure up to the standard/paradigm of what a derecho is meant to represent. Others may disagree, and that's fair. There is no 100% crystal clear technical definition of a derecho because all of the points in the stated definition are subject to some degree of subjectivity.

measured_wind.png
 
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