January: Increasing Clouds/Rain & Warmer To End Month

[wxman57]

Note that the 00Z Euro which shows the upper low moving across SE TX next Monday evening has surface temps at 50 degrees at sunset and 45 degrees at midnight. However, it does have 850mb temps at about 30-32 degrees and 925mb temps at 35-40 degrees. Cold temps aloft could allow for snow formation if there is any remaining moisture in the atmosphere by that time. Euro has less than 0.1" of precip in the cold air Monday evening.

6Z GFS is about 5 deg warmer than the 00Z Euro across SE TX (surface and aloft), but it did match the Euro with the passage of the upper low, something the 00Z GFS didn't have. I'm not holding out much hope of a SE TX snow miracle. Remember that the Euro was WAY too cold aloft across Texas with the current airmass across Texas. At one time it had 850mb temps over Houston down to -13C today.

[MontgomeryCoWx]

It's easy to dismiss snow and wintry events in Houston because 90% of the time you'll be right. It's really hard to get the timing correct.

Now, ice storms should be more prevalent here, but surprisingly they are not.

[MontgomeryCoWx]

I agree. I still think places like Conroe, Huntsville, College Station and Montgomery would see more Ice Storms, but they don't. They are far enough away.

[srainhoutx]

The 12Z WRF/NMM continues to suggests a much further W short wave and a bit more potent feature for Thursday. As a reminder to wxmna57 aka Mr. Extreme Heat, all the guidance had us bone dry and warm all this week. What is becoming clear is a weak frontal boundary will stall along the coast setting the stage for some over running showers/light rain and increased fog chances as we head into the weekend. What happens with that next potent upper low remains to be seen.

What is getting my attention is the cold weather that is lurking in the mid month time frame. The Euro has joined the GFS in suggesting a –AO, -EPO and –PNA regime that bodes well for Arctic intrusions into the Western 2/3 of the CONUS. A +NOA would suggest a SE Ridge would remain, sort of locking the cold in the Western Areas and keep our neighbors along the East Coast warm. There is also some indications that some MJO help is in the works as it travels from octant 5 toward 6-7-8, although weak. Add into the mix another SSW (Sudden Stratospheric Warming) event now showing up via the Euro. We now see all the guidance sniffing significant cold air building across NW Canada and a relaxation of the ever present Alaska Vortex. Heights are now forecast to build across the Aleutians into the Arctic region suggesting the coldest air of the season will build on our side of the hemisphere. The mid to late January time frame is becoming increasingly interesting for the cold weather lover and just perhaps other miracle chances will come when conditions would be much better. Stay Tuned!

[srainhoutx]

I agree. I still think places like Conroe, Huntsville, College Station and Montgomery would see more Ice Storms, but they don't. They are far enough away.

The did happen in the 70's around these parts and extended well toward the Coast. Many long time residents will recall the amount of major tree damage from falling pines from those events of earlier years.

[Portastorm]

The 12Z WRF/NMM continues to suggests a much further W short wave and a bit more potent feature for Thursday. As a reminder to wxmna57 aka Mr. Extreme Heat, all the guidance had us bone dry and warm all this week. What is becoming clear is a weak frontal boundary will stall along the coast setting the stage for some over running showers/light rain and increased fog chances as we head into the weekend. What happens with that next potent upper low remains to be seen.

What is getting my attention is the cold weather that is lurking in the mid month time frame. The Euro has joined the GFS in suggesting a –AO, -EPO and –PNA regime that bodes well for Arctic intrusions into the Western 2/3 of the CONUS. A +NOA would suggest a SE Ridge would remain, sort of locking the cold in the Western Areas and keep our neighbors along the East Coast warm. There is also some indications that some MJO help is in the works as it travels from octant 5 toward 6-7-8, although weak. Add into the mix another SSW (Sudden Stratospheric Warming) event now showing up via the Euro. We now see all the guidance sniffing significant cold air building across NW Canada and a relaxation of the ever present Alaska Vortex. Heights are now forecast to build across the Aleutians into the Arctic region suggesting the coldest air of the season will build on our side of the hemisphere. The mid to late January time frame is becoming increasingly interesting for the cold weather lover and just perhaps other miracle chances will come when conditions would be much better. Stay Tuned!

The most encouraging post of the season (unless you are wxman57!).

[wxman57]

Hey, I was on board with the 2004 Christmas Eve snow miracle 2 weeks before it hit. Even made a bet with a client that we'd see snow around Christmas and won a steak dinner.

[MontgomeryCoWx]

Hey, I was on board with the 2004 Christmas Eve snow miracle 2 weeks before it hit. Even made a bet with a client that we'd see snow around Christmas and won a steak dinner.

What sold you on that miracle, and more importantly, what made you have any confidence in any wintry precip here outside of a 3 day forecast?

Were the models all in agreeance or were you hitting the Egg Nog a lot earlier that year?

[wxman57]

Hey, I was on board with the 2004 Christmas Eve snow miracle 2 weeks before it hit. Even made a bet with a client that we'd see snow around Christmas and won a steak dinner.

What sold you on that miracle, and more importantly, what made you have any confidence in any wintry precip here outside of a 3 day forecast?

Were the models all in agreeance or were you hitting the Egg Nog a lot earlier that year?

I can't remember what sold me on the 2004 event. Perhaps it was the GFS's consistency run-to-run between 10-15 days out. Often the GFS sees a major event correctly in the very long range, only to lose it completely in the mid range (4-9 days). I'm seeing way too much run-to-run inconsistency to believe the GFS for next Mon/Tue. Just watching the 12Z come in now and it does have the same upper low passing Monday evening as the 06Z (which the 00Z didn't have on the map at all). However, it still has surface temps in the 40s Monday evening. It's possible for snow to reach the surface if the precip forms in sub-freezing air aloft and the surface warm layer is very thin. I'm not banking on it at this time for next Monday - yet.

Note that the 12Z GFS does have more significant precip in the cold air than did the 6Z. The vertical temperature profile is the big question. 12Z GFS also has Houston above freezing for the next 16 days.

[MontgomeryCoWx]

Thank you... still trying to understand the intricacies of each of these models.

[wxman57]

GFS does indicate a small area of accumulating snow next Monday night:

http://www.twisterdata.com/data/models/ ... URFACE.png

It's forecasting temps to be above freezing across much of SE TX next Monday night, so it's not forecasting anything to accumulate. Doesn't mean there can't be snowflakes falling and melting, though. Will be interesting to see if the models hold onto this pattern through early next week.

[srainhoutx]

The 12Z Canadian still appears a bit too progressive, but also indicates some moisture available as the upper low crosses E Texas. That model had been dry for our area, so that is a bit of a change.

[tireman4]

Wxman57,

Can another fly in the ointment be the soundings? Was that not a problem last winter?

[wxman57]

Interesting that the 12Z Euro completely backed off of any TX snow next Monday night and delayed the passage of the upper low 24 hours with much warmer temps aloft.

[srainhoutx]

Interesting that the 12Z Euro completely backed off of any TX snow next Monday night and delayed the passage of the upper low 24 hours with much warmer temps aloft.

Typical Euro throwing out a run where it drops enenrgy too far SW and cuts it off. I'm actually surprised that this common Euro bias did not show up until today.

[srainhoutx]

By hour 192 the Euro does have the cold core upper low crossing Central/SE TX and temps aloft could be borderline after all...

[srainhoutx]

And look at the cold air dropping S behind that upper low...

[srainhoutx]

The HPC will hold off on any whole sale changes with the afternoon Final Update...

FINAL...

THE ONLY NON-COSMETIC CHANGE TO THE UPDATE PACKAGE FOR THE FINAL
ISSUANCE WAS OVER THE PACIFIC NORTHWEST DAY 6...WHERE ADJUSTED THE
POLAR FRONT SOUTHWARD A BIT IN LINE WITH THE 12Z/03 MODEL AVERAGE.
OTHERWISE...THE UNCERTAINTY IN THE SOUTHERN STREAM LATE IN THE
PERIOD CONTINUES...WITH THE RELIANCE ON THE ECENS MEAN STILL
LOOKING LIKE THE SAFEST BET.

[MontgomeryCoWx]

What's your gut feel with this ULL srainhoutex?

[wxman57]

And look at the cold air dropping S behind that upper low...

Can't tell what that chart represents, srain. What is the valid time? I'm comparing it to the Euro ensemble and operational forecasts (which are both much warmer) and can't match it up with anything.