Texas/New Mexico/Louisiana/Mexico Obs And Discussion Thread Part 8

[cheese007]

SPC out with a slight risk for severe storms in the eastern half of NTX. Certainly feels like a stormy day outside

[Sydney Claridge]

2 hours ago, cheese007 said:

SPC out with a slight risk for severe storms in the eastern half of NTX. Certainly feels like a stormy day outside

It seems that convective initiation is starting along and east of a line from DFW Airport up through Sherman, based on seeing small pops of heavier returns on the radar surrounded by no returns at all.  There are also patches of drizzle southwest of Fort Worth. 

We'll have to see how the storms develop.

[cheese007]

WFAA talking about a potential tornado watch including part of the metroplex. Hype machine needs somethinf I guess

 

EDIT: 

Tornado Watch for portions of 
     Western Arkansas
     Eastern Oklahoma
     Northeastern Texas

[Roy]

Line forming in Tarrant unfortunately just east of me. But, nice to hear thunder!

[aggiegeog]

Two tonado warnings east of DFW right now. One over Lake Tawakoni and one just east of Corsicana.

[raindancewx]

Looking through the MJO forecasts and comparing them with history, not a lot of January MJO propagation like this year, when factoring in phase and magnitude.

I like January 1986 best, easily the closest propagation with 2-3-4-5-6-7 observed, we began in two this year. Doesn't appear we'll have any neutral MJO conditions in January. The magnitude in 1986 was greater than this year though. January 1978, 1989, 1990 are decent. I'd go 1986 x7, the others x1 each. 1988/1989 start in 1 and 3, but blended together, they start in two at lower magnitude than 1986. 1977 started in neutral, so its behind. Timing is closest to 1989/1986, but the MJO has been moving through the phases about a week later overall.

Black line is January observed MJO conditions. Red line that I drew is the Euro forecast for the rest of January 2018. February 1986 is one of my all-time snowy months, and very wet too - would be nice to get it. City had 10.2" snow I believe, near the end of the month.

Here is December 2017, v. the MJO blend I outlined above, plus one week.

[raindancewx]

Will be interesting to see how some of my pet theories play out in March. Nino 1.2 & Nino 3.4 conditions can be re-created for Nov-Jan using two sets of analogs (will change if Nino 1.2 or 3.4 warms rapidly this week).

Major Hurricanes Hitting TX Analogs: 1967, 1970, 1980, 1999. OR Low Solar Analogs: 1934, 1934, 1934, 1964, 2007, 2007.

First blend and second blend are each at -0.80C and -1.10C in Nino 3.4 and Nino 1.2 respectively, against 1951-2000 data according to this data, which is what NDJ looks like to me.

https://www.esrl.noaa.gov/psd/gcos_wgsp/Timeseries/Data/nino12.long.anom.data (change 12 to 34 for Nino 3.4)

First blend has high solar activity (opposite to now), but features years after a major hurricane (correct) hit Texas. Second blend has low solar activity (correct), but features years without a major hurricane (opposite to now) hitting Texas. I couldn't re-create the NDJ conditions in Nino 3.4 and Nino 1.2 with low-solar condition AND a major hurricane hitting Texas.

The first set of years is pretty wet in March, second set is quite dry. So, I went to tie breakers -

The first set of years is very wet in August+October, a good indicator of a wet March - we were dry those months this year. The second set of years is dry in those years.

However, August + Sept 27-Oct 26 was very wet in 2017 (2.2" Sept 27-30 here) like the major hurricane years, but the non-major hurricane years were very dry in that period.

[aggiegeog]

As expected the weather looks to turn very cold and possibly stormy as we enter February. A big Pacific ridge extending into Siberia along with a mean trough over the West which slowly slides east.

[raindancewx]

I was checking some of the conditions in the East, looks like Philly is now within 2F or normal month to date with the 23rd included, with some warm days ahead yet and the West's heat will gradually shrink as well. I had the East warm in January and the West cold in January - that looks pretty bad for actual January, but its probably just going to be two weeks early in the end. Although the East will probably be mostly within 2F or normal by the end of the month. Jacksonville is within 3.5F of their normal, when the 23rd is included. 

My lows are running 2.5F lower than last year to date, with the dryness more than offsetting the somewhat warmer highs (+2.3F) so far.

[cheese007]

7 hours ago, aggiegeog said:

As expected the weather looks to turn very cold and possibly stormy as we enter February. A big Pacific ridge extending into Siberia along with a mean trough over the West which slowly slides east.

Stormy as in snowy or stormy as in severe?

[wxmx]

14 hours ago, cheese007 said:

Stormy as in snowy or stormy as in severe?

The former, looking at the air masses source region. The pattern looks tightly coupled to a currently strong MJO wave. Models are usually too fast with it, so I'll say that we'll see some delay on the arctic outbreak to the second week of February.

[aggiegeog]

16 hours ago, cheese007 said:

Stormy as in snowy or stormy as in severe?

Stormy as in unsettled with a trough extending into the SW US. Canada will be very cold so severe for the Southern Plains appears unlikely.

[raindancewx]

February looks like a wild month to me - couldn't find any years where the MJO goes (roughly) through phase 2-6 in January at high amplitude and then stays very active through February, which looks possible. 1978 & 1990 are better analogs in Feb than now if the amplitude stays high. Since the 70s the high amplitude January years crash and the low amplitude January years tend to see increased magnitude in February.

[wxmx]

Models are showing the coldest and most expansive air mass of the season in Canada, with the NE Siberian and West Coast ridges joining up in Alaska, in a classic -EPO configuration. Temps < -40C/F bottle up and are ready to burst the dam by the end of the first week of February. The question is if it's going to be a direct hit or a glancing blow, as these super dense air masses can't be kept forever up there.

 

* First time I see a 1070mb high in NW Canada in the GFS...although it's day 13

[WhiteoutWX]

3 hours ago, wxmx said:

Models are showing the coldest and most expansive air mass of the season in Canada, with the NE Siberian and West Coast ridges joining up in Alaska, in a classic -EPO configuration. Temps < -40C/F bottle up and are ready to burst the dam by the end of the first week of February. The question is if it's going to be a direct hit or a glancing blow, as these super dense air masses can't be kept forever up there.

 

* First time I see a 1070mb high in NW Canada in the GFS...although it's day 13

+AO argues for glancing blows at these latitudes, but we'll see.

[wxmx]

2 hours ago, WhiteoutWX said:

+AO argues for glancing blows at these latitudes, but we'll see.

But the AO and EPO are forecasted to go negative

[raindancewx]

Looking highly likely at this point that Albuquerque finishes November-January with 0.03" precipitation, the lowest figure for that period 1931-32 to now. Been working on a Spring outlook (will link it here in two-three weeks when all the data is in), and it is looking pretty warm/dry here for most of Spring.

1) When Nov-Jan is dry here, following May is almost always dry (9/10 driest Nov-Jan followed by a dry May, in all other years, 38% shot at a wet May).

2) We've had two wet Aprils in a row, in ten other instances of that happening (or close calls), only one of the following Aprils was wet.

3) Dry Nov-Jan periods do heavily favor a wet June, an inch of rain in June or more is 5x more likely after a dry Nov-Jan here. I have other methods for predicting precipitation that like June too. June is a strong indicator of the following winter here, you can virtually (94%) rule out a cold winter here if June is >=92F for the high. Wet Junes (>=0.6") are under 92F 97% of the time here.

The MJO implies we have a shot at some major precipitation in February or March, as do some of my precipitation and temperature replication techniques - after that, I think we get almost jack until June. The CFS seems to be trying to move toward a wet February and/or March in the SW?

Also, the Monsoon is (weakly) linked to three factors here - annualized sunspots, precipitation Nov-Apr before Summer, PDO values Nov-Apr before Summer. The ideal Monsoon years, like 2006, tend to have a low, low, positive blend on the three factors. Pending any sudden PDO or precipitation changes, this kind of looks like a strong Monsoon year, at least conceptually. For now, a blend of 1934, 1934, 1943, 1994, 2006, 2010, 2010 looks about right. Last year the PDO was more favorable, but we had a lot of precipitation in Nov-Apr before Summer. On balance, this year looks better.

[aggiegeog]

The potential is there for a very cold February for almost all of NAm. Only thing lacking is a -NAO to generate a storm though they matters more for East of Texas. For us to get snow out of this We will want to see periods of neural PNA allowing for SW US troughs.

 

[WhiteoutWX]

15 hours ago, wxmx said:

But the AO and EPO are forecasted to go negative

While the model forecasts may technically be showing a flip to -AO in the longer range, they're also showing a very strong and in-tact vortex over Canada, which does not bode well for extended cold at lower latitudes. 

[wxmx]

1 hour ago, WhiteoutWX said:

While the model forecasts may technically be showing a flip to -AO in the longer range, they're also showing a very strong and in-tact vortex over Canada, which does not bode well for extended cold at lower latitudes. 

A PV near the Hudson Bay is one of the elements present in a McFarland signature. A tightly wound vortex won't unload the cold into the lower latitudes, or it will in small doses, but a deep storm moving south from the upstream flow can relax the heights into the lower latitudes. That can happen if we get a strong west coast ridge, better if it connects to the EPO ridge (we have had a few this winter). It can lead to suppression (again, this winter), but a not so strong ridge (neutral PNA) can benefit the southern Plains with a storm.

All this is speculative, and, as I said before, I think the models were too fast with the pattern change to colder, and as expected they have been delaying the cold dam burst past day 10. But a passage of a coherent MJO wave into phases 8-2 would activate the above mentioned storms, and relax the heights with high amplification. With a so cold and dense air mass, you don't even need that much amplification, and even can have overrunning events without a strong mid level storm present.

The synoptic events to watch are 1. the migration of the Aleutian ridge to NE Siberia then progress east to Alaska, plus a strong vortex near the Hudson Bay...that's a recipe for very cold anomalies in Canada (very confident it will happen) and 2. a ridge building near the West coast, that allows amplification, and storms to ride south, downstream from said ridge and upstream from the Canadian vortex (much more iffy, especially considering it's in the long range).

[raindancewx]

My dream MJO scenario at this point is the red path. Would be pretty shocked at this point if we got the yellow path. I'm not a huge fan of 2006 as an analog for January on the MJO or for the subsurface, but if we migrate it at this amplitude, and the warmth stays in the subsurface below the Nina, we're going to do some major Nina damage too.

The MJO went through phase 3-4-5-6-7 in Jan 2006, similar to this year, which is 2-3-4-5-6 in January. Less anomalous subsurface heat/cold v. 2006

[Roy]

So basically are we getting extreme cold again to where we can't have storms like December north of Austin, for that's what it sounds like to my untrained ear/eye.

[wxmx]

1 hour ago, Roy said:

So basically are we getting extreme cold again to where we can't have storms like December north of Austin, for that's what it sounds like to my untrained ear/eye.

Not necessarily...you can get a Baja low that doesn't dig that far into MX and some ridging near the SE coast. That could create a nice bowling ball low for N TX. Also, you can get a big low level high moving south the plains, with ridging in MX...that would be a good setup for overrunning events in N TX as well.

What I'm trying to highlight is that there's a good chance that we'll get a very cold source in Canada and that eventually the cold dam will burst. Whatever happens next is up for grabs.

[raindancewx]

My Spring analogs have a February look that is like a less extreme version of November...but I think something like this is more likely given where the MJO is -

These are my preliminary Spring analogs.

The MJO will be in phase 6-7 at the start of February looks like, so the map probably looks like the second map for the East in February, but looks more like the first map after Feb 5 or Feb 10, maybe through early March. The Spring analogs are a blend of MJO expectations, Ninas that were coldest east of 120W in NDJ, low-solar, and rare conditions locally (super dry since Oct 1, warm in Nov-Dec, etc).

[raindancewx]

The SOI spike from -2.6 in December to +10.0 or so in January is fairly rare. If you use SOI analogs that are +/-4 for each month only similar winters are:

1934-35, 1936-37, 1985-86, 2005-06, 2013-14

Not exactly cold here, but only +2F in February, and then a normal March. Possibility of heavy rain and/or snow in Feb/Mar, and then May/Jun.

[aggiegeog]

GEFS beyond this weekend is -EPO, +PNA with dominating PV anomaly over Hudson Bay. This is a clear cold east of the Rockies pattern. This also does not leave much room for storms to develop sadly. Will again have to rely on NW flow clippers to find some moisture. If the +PNA could relax for a moment during this maybe we could get a storm, but it would likely again favor South Texas and the Gulf Coast.

[wxmx]

35 minutes ago, aggiegeog said:

GEFS beyond this weekend is -EPO, +PNA with dominating PV anomaly over Hudson Bay. This is a clear cold east of the Rockies pattern. This also does not leave much room for storms to develop sadly. Will again have to rely on NW flow clippers to find some moisture. If the +PNA could relax for a moment during this maybe we could get a storm, but it would likely again favor South Texas and the Gulf Coast.

Yeah, fully agree with your assessment. Looks like constant cold seeping south, east of the Rockies, but dry overall, other than South TX, MX and the Gulf Coast, which could have drizzle and lows developing east of Brownsville. Unless we get that strong PV weaken, move south and elongate in a positive trough, lowering the heights in the SW, much more colder and wetter prospects look hard to obtain.

[wxmx]

Looking at the MJO, the GEFS and EPS continue to show a very strong wave about to enter phase 7, but past day 7 significantly slowing and losing amplitude. The operational models aren't as aggressive with the wave plummeting, and that would be a better prospect for storminess overall.

[Roy]

It's now virtually February, and I am thinking La Nina will win out this year. Sad. At least we had some cold. But, all the talk of a great western trough has vanished.

[aggiegeog]

Umm, the most extreme 12Z GEFS member is showing lows on the 12th way below 0 (-20s in NE TX) with even some sub 0 highs. Lets hope we can toss out that possibility, but mean lows around 20 for days 10-16 is still crazy. Thursday morning is the only morning in the 16 day run with a mean low over 39. Wish there was more precip showing up, but that's life with persistent cold NW flow.