Texas 2024 Discussion/Observations

[Stx_Thunder]

With all this above normal Gulf warmth next to Christmas, not surprised SPC is possibly under-doing things (again) later today on Christmas Eve with just a marginal risk area on this early morning's D1 outlook. Both Euro & GFS are actually showing a pretty volatile convective environment around the I-10 corridor (SAT - HOU areas) with the next front moving through the state. I also saw an isolated storm not far offshore yesterday afternoon that lasted for a while on its own when I was out and about.

DL shear doesn't look to be really strong, but still notable areas of 40 - 50 knots by early evening in San Antonio region. Multi-global model output also showing near 100% thunder risk areas. And this time moreover, ML lapse rates look to be pretty steep (closer to 8 or even possibly above). Potential steep LL lapse rates also as the front will be coming into the region at best time of day (later afternoon).

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At this point on model runs, Thursday's (26th) setup isn't looking anywhere as convectively unstable in E/SETX. Despite better projected shear.

[Powerball]

Now this is a nice Christmas present.

T'Storms with Flash Flooding...

[Stx_Thunder]

Some real (sfc-based) Christmas thunder action going on around the I-10 corridor SC - SETX region this evening. Roughly between San Antonio - Houston now. Radar showed a few convective tops getting close to 50 Kft in the past 2 hours near SAT on the southern most cells. Quite high for this time of year.

Decent amount of severe hail reports in the past several hours of > 1 in., and a large hail (2 in.) report near Caldwell.

 

[Stx_Thunder]

Robust convective environment around the I-10 corridor region for Christmas tonight, alright. Definitely looks like an early/mid spring convective pattern or MCS.

+CGs really went on from around midnight until about an hour ago.

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Should also note that the ML temp profile aloft is pretty cold as H7 temps were only 4 C in STX, and closer to -20 C further north @ H5 on yesterday evening's obs sounding data.

[Chinook]

chance for tornadoes tomorrow, including Houston, Shreveport

[Stx_Thunder]

Still looks more like a heavy rainfall/flash flood threat. Rather than severe threat over E/SETX later today (26th).

The globals have also backed off more on the amount of substantial inland CAPE penetration from a few days ago on runs. Except around Houston area (near coast). The Gulf warm sector or old Christmas Eve front that caused all the robust storms last night doesn't look like it'll move back far enough north to really bring back convective instability looking at dew point projections also (like the environment already was Christmas Eve).

Precipitable water is projected to get close to 2 in. on both Euro & GFS (near 1.8" now on GFS). Which is actually a good ways above normal for this time of year, being wintertime especially. So I definitely agree with WPC's excessive rainfall outlook slight risk area over a larger area of ETX. Maybe even DFW area. If it's another potent shortwave coming in like the Christmas Eve one, it might border on moderate risk level in some areas over E/SETX. Especially with such above normal PWs being projected and all accumulated rainfall around there since December began. Some areas have seen 5 in. (bit higher in some spots looking at TexMesonet data), just in the past 2 weeks. I'm sure that's fairly high for December standards even for that region.

[Chinook]

SPC has put up a 10% (enhanced) level of threat for tornadoes north Houston. It is mid-winter, so I don't know if this level of risk will work out.

[Powerball]

On 12/24/2024 at 11:00 AM, Powerball said:

Now this is a nice Christmas present.

T'Storms with Flash Flooding...

A repeat of Christmas Eve today with more T'Storms and Flash Flooding...

[Chinook]

not a lot happening in TX, but still getting further discussion from SPC

Quote

 Areas affected...Southeastern Texas

   Concerning...Tornado Watch 715...

   Valid 261914Z - 262115Z

   The severe weather threat for Tornado Watch 715 continues.

   SUMMARY...The severe threat continues across much of southeast Texas
   as storms intensify across the region.

Quote

In the short term, the greatest severe/tornado risk will
   likely be associated with the stronger cells within the line
   approaching the Houston area and in far southeast TX where low-level
   mesocyclones associated with persistent supercells have been noted.

 

[Powerball]

2 minutes ago, Chinook said:

not a lot happening in TX, but still getting further discussion from SPC

 

Storm mode's looking quite messy, which is a good thing.

Meanwhile, between Christmas Eve and today, MBY has picked up easily 4" of rain.

 

[Chinook]

non-warned storms with shear/rotation

[Chinook]

the north storm near Hardin has a PDS tornado warning

[Chinook]

tornado reported near Dayton, TX

[canderson]

Big bust in Texas for severe today. Good. .  

[Chinook]

this is about 45 miles from Shreveport

[Stx_Thunder]

Saw significant areas of 2 - 3 in. for yesterday's storm totals over ETX. That now brings accumulated rain totals actually up to and even over 10" in a couple spots over far ETX since the last few days of November. Which is well above normal now for this month in December there no matter how you look it at it. I also looked at some average monthly rainfall climatology map data for December to verify. This has basically become a repeat of the late spring ETX waterlogging earlier this year.

Also, HGX radar estimated about 5 in. area yesterday with the stronger cells not far east of Houston, near Beaumont. Victoria area also got lambasted with several inches of rainfall in just a few hours from the Christmas Eve night thunder system (flash flood warnings obviously issued there that night going into Christmas morning).

 

This looks to be it for major convective events for the rest of 2024. Winter looks to return to the whole state by the very start of 2025. Which will be nice with all things considered of late.

[Powerball]

DFW may be on track for a top 10 warmest December this year.

In addition, to-date, 2024 is currently tied with 2023 for the 2nd warmest year on record (69.7*F). For perspective, the warmest year on record is currently 2017 at 69.8*F.

Once 2024 officially concludes and knocks 1933 off the list, the oldest year in the top 10 ranking will be 1998 (and 8 of the 10 years will have all been in the 21st century)

[Stx_Thunder]

Looking ahead into 2025 (before new years celebrating comes), just saw the latest 0Z Euro and GFS runs on projected temps after Jan 5th across the state. Ensembles not going as cold at this point, but CFS is also trending colder in the state as well in the last few runs. And, AO is forecast to go back negative (possibly significant phase) in the beginning of January.

Am more surprised Euro is going colder than GFS here. Which usually isn't the case this far out.

[Stx_Thunder]

Before winter starts returning to the state going into the new year, McAllen reached & set a new record high of 91 F yesterday. Which even there by December is well above normal (about 20 degrees). Previous record, 89 F in 2016.

The potential is definitely there for another record-breaking heat spike into the 90s in deep STX tomorrow ahead of the first in a series of winter-returning cold fronts. NBM output from what I was reading on Brownsville AFD this afternoon going as high as 95 F. Which definitely is not out of the realm of possibility in the McAllen/Rio Grande City area considering GFS showing 850mb temps > 20 C and a typical south-southwesterly pre-frontal LL flow.

[Stx_Thunder]

More 90s starting to show up over STX this afternoon than forecast. Especially closer to the Rio Grande/Laredo area. There's a dryline moving into the region with southwest - west surface flow and dropping DPs on obs. So looks like a good amount of records are going to be broken today across the region.

Even San Antonio is next to 90 F now which I'm sure is already in record territory.

[Powerball]

Today's high at DFW was 82*F officially, several degrees above the forecasted high.

[Powerball]

Not only will this December be a top 3 warmest for DFW (surprising considering how milquetoast the month started and no real extreme warmth), it should also be good enough for DFW to tie the warmest yeard on record with average temperature of 69.8*F (the previous record was set in 2017).

EDIT: 

Should also add:

All top 5 of the warmest years on record will now have been since 2010 years (2024, 2017, 2023, 2016 and 2012).

[Powerball]

[aggiegeog]

Next week is a beautiful pattern for snow across TX. On edge of an Arctic air mass which sends down waves of cold while still allowing for shortwaves to pass overhead. While this is ongoing a trough digs into the SW USA allowing us to tap into Pacific moisture on top of the Gulf moisture that will be pulled up by surface lows.

[Stx_Thunder]

To note, the most notable heat spike record highs over the southern part of state on December 30th are:

 

San Antonio at 89 F (previous 83 F in 1951)

McAllen at 94 F (previous 89 F in 1945)

Victoria at 87 F (previous 82 F in 1973)

 

Fairly extreme records to end 2024.

[aggiegeog]

GFS is the most consistent with next week's storm and it is consistently showing a near ideal set up for a nearly statewide significant snow event.

[aggiegeog]

NWS office are now inserting snow into days 6/7. For now they are keeping it south of I-20 where the better moisture will be.

[Stx_Thunder]

9 hours ago, aggiegeog said:

GFS is the most consistent with next week's storm and it is consistently showing a near ideal set up for a nearly statewide significant snow event.

Actually, GFS wasn't going very cold and didn't start blowing winter precip up over the state until a couple days ago. Euro's actually been more consistent overall since around or just after Christmas with this likely winter cold outbreak next week. The much colder air intrusion is pretty much a certainty now. Especially because of the already strengthening ongoing -AO phase. But the winter precip potential across TX is still more like 50/50 as things stand today looking at all the model data over the last several days as well. Which is also harder to project than colder temps. Especially still being a week away FYI.

I haven't read their AFD today but the likely reason Dallas/Fort Worth NWS office is keeping the better precip south of their CWA is because the stronger continental airmass intrusion or deeper northerly L-ML flow in NTX could dry out the column more than to support any real precip around there when the energy from the advertised SS Low out west later next week takes shape. The Euro ensemble system (EPS) is starting to show this over DFW area in today's 12z run. GEFS also isn't showing much either over NTX.

[aggiegeog]

What's nice about this pattern is we are in a pattern which will supply continued shots of cold and snow into Feb. Some serious cold will be seen with this as we build a solid snow pack all the way down the Plains.

[aggiegeog]

The morning models have the SW trough missing the PV phase. If that happens next week's snow would not happen as the cold will leave before any moisture arrives.