Jump to content
  • Member Statistics

    17,601
    Total Members
    7,904
    Most Online
    ArlyDude
    Newest Member
    ArlyDude
    Joined

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


wxmx
 Share

Recommended Posts

15 minutes ago, DFWWeather said:

Strongly agree...and in this case the colder drier solution looks correct imho. Given the amount of Arctic air that will be flowing down from the north, flow coming almost due north from the Arctic circle, the deeper, colder solution the ECMWF has looks correct. This is a McFarland setup. Folks, this is not a favorable upper air pattern for big DFW winter storm. The op GFS looks like an outlier to me and doesn't agree with the majority of its ensemble members. If anything, further south would be a target for frozen precipitation. I would not be surprised for freezing temps getting into LRGV with this setup.

The EPO going postive allowing for mid month warmup looks in error as the long wave global synoptic pattern says that should stay negative. AO, NAO, WPO, PNA, EPO (arguably) remaining negative points to widespread CONUS cold (save for Florida). Climate Prediction Center is in agreement as well with cold lasting well into week 2 of January. Joe Bastardi explains this today in his morning video. With Greenland blocking this cold is going to be in no hurry to leave with more building up behind it.

Yep, la nina plus big -EPO seems to favor the full latitude trough. 

Link to comment
Share on other sites

38 minutes ago, vwgrrc said:

I thought the McFarland Signature was what contributes to the Dec 2013 dfw ice storm? But maybe I was wrong. 

Full McFarland setups are associated with the storm track well to our south, severe cold, and freezing temps into the LRGV (as McFarland wrote about this pattern to be associated with the LRGV most devastating freezes, thus why it was given the name McFarland Signature). While snow and ice can still fall this far north in these setups, it is usually very light as we are so deep into the cold air that it becomes very dry, usually associated with 0°F isodrosotherm well to our south. Occassionally, large storm systems can time with the onslaught of cold air to produce heavier storms right after frontal passage. However, in this case the storm system is held back till Thursday well after the Arctic surge which would mean an unusually far south storm track and we would be well established in much drier air that it would have to fight at that time to get precip to the ground.

Link to comment
Share on other sites

Looks like the drought in much of California is shrinking. Pretty good match of the classic 'AMO/PDO' both positive drought expectation map except in the NW, due to the La Nina flavor. East Coast, California, Colorado drought definitely matches. May end up being a really nasty thunderstorm season in Spring if it stays warm/dry in the SE with big storms coming into the NW/SW

Image result for amo pdo drought

End of 2016 Drought Status.png

Link to comment
Share on other sites

35 minutes ago, raindancewx said:

Looks like the drought in much of California is shrinking. Pretty good match of the classic 'AMO/PDO' both positive drought expectation map except in the NW, due to the La Nina flavor. East Coast, California, Colorado drought definitely matches. May end up being a really nasty thunderstorm season in Spring if it stays warm/dry in the SE with big storms coming into the NW/SW

Image result for amo pdo drought

End of 2016 Drought Status.png

I was looking at that the other day and with models showing ENSO warming it could be a wet spring. 

Link to comment
Share on other sites

24 minutes ago, bubba hotep said:

What a train wreck on the 00z GFS :lol: 

Well, unfortunately, this happens a lot during this time of the year. We should probably really not looking at what model says about precipitation outside 3 days. NWS AFD today also highlighted the uncertainty.

Link to comment
Share on other sites

21 hours ago, bubba hotep said:

Yep, la nina plus big -EPO seems to favor the full latitude trough. 

After flipping through some analogs, the current +PDO seems to be the wrench in things. Dec '83 was during a +PDO but most others were during -PDO periods - '49, '51, '62, '64, '73, '75, '13. Over the last few days there was a pretty big warm signal in the ensemble spread with the operational runs on the colder edge of the spread, so the potential was always there for the ops to trend warmer.    

Link to comment
Share on other sites

It looks like the CAPE will be higher at nighttime than in the daytime. There might be a half-dozen storm reports at 4:00AM. The convection-allowing models show showers and thunderstorms traveling or developing some 300mi+ eastward across Texas in the time frame of 06z to 12z. There could be a number of severe storms. It would be very climatologically unusual for a severe storm at 3:00AM on January 2nd.

Link to comment
Share on other sites

1 hour ago, Chinook said:

It looks like the CAPE will be higher at nighttime than in the daytime. There might be a half-dozen storm reports at 4:00AM. The convection-allowing models show showers and thunderstorms traveling or developing some 300mi+ eastward across Texas in the time frame of 06z to 12z. There could be a number of severe storms. It would be very climatologically unusual for a severe storm at 3:00AM on January 2nd.

Plenty of anomalously high PWAT air pooled up across the northern Gulf right now. 

Link to comment
Share on other sites

I'm fairly optimistic for the late winter / early Spring. The La Nina signature looks like it weakened quite a bit in Oct-Dec, and the Atlantic temperature anomalies have cooled quite a bit in the last six weeks from near record warmth. Both are good for storms taking a southern track more consistently.

By my count, Nino 3.4 has been above the La Nina threshold for 33 of the last 90 days, including 19 times in December. Expecting OND to come in around -0.5C to -0.6C, and then NDJ to be -0.5 or -0.4C at this point.

More generally, even with the huge snows in late Feb 2015 in New Mexico, we've had three torch Februarys in a row here. I'm expecting a correction this year, even if it is only to "average" and note cold. The big rains/snows have been coming in 45 and 90 day increments though, so I wouldn't be shocked if February ended up snowy/rainy and cold given how November was. CPC has half of Arizona and NW New Mexico favored to be "wet" in January which is not exactly La Nina like, so even they be recognizing it is deteriorating. It is a bit similar to 1978 in that respect, as 1978 had a respectable La Nina in Fall that collapsed in Winter even though the rest of the Atlantic/Pacific are pretty different.

New Canadian should be out in an hour or so, will be interesting to see what it thinks is going to happen. Suspect it will trend colder in the middle of the country and wetter in the West.

Edit: It is wetter in the West! 

Nino 3.4 Oct-Dec 2016.png

Link to comment
Share on other sites

Looks like the 1st watch will snag Ft. Worth but Dallas and areas east of I35 will have to wait until later:

C1I1HiZWQAAGgky.jpg

Mesoscale Discussion 0002
   NWS Storm Prediction Center Norman OK
   1011 PM CST Sun Jan 01 2017

   Areas affected...Much of Central Texas

   Concerning...Severe potential...Watch possible 

   Valid 020411Z - 020645Z

   Probability of Watch Issuance...60 percent

   SUMMARY...Thunderstorms will increase in coverage and intensity
   later tonight, with damaging winds and hail expected. A watch may be
   needed prior to 06Z.

   DISCUSSION...A rapidly moving cold front continues to move eastward
   across West TX, with several wind gusts in excess of 40-50 kts
   measured and only sporadic lightning. This front will gradually
   interact with an increasingly unstable air mass, still well to the
   east as of 04Z. However, increasing flow in the low levels just
   above the surface will help transport mid to upper 50s dewpoints
   northward out of South TX, with a rapid uptick in storms along the
   front expected as MUCAPE of 500-1000 j/kg develops. This in turn
   should allow for a line of storms along the front, with both wind
   and hail possible.

   ..Jewell/Hart.. 01/02/2017
Link to comment
Share on other sites

4 hours ago, vwgrrc said:

Probably not for TX. Looks like any precipitation should be very light at this time...  

GFS now coming back on board also. Not seeing any signs of a huge event, but there is a good shot for those north of I-20 to see 2-4". The cold is coming with storminess behind it,  that is a very good snow signal though without a STJ connection it is doubtful that we see anything heavy. 

Link to comment
Share on other sites

5 minutes ago, aggiegeog said:

GFS now coming back on board also. Not seeing any signs of a huge event, but there is a good shot for those north of I-20 to see 2-4". The cold is coming with storminess behind it,  that is a very good snow signal though without a STJ connection it is doubtful that we see anything heavy. 

Agree. 18z does look changing. But I wonder if this gonna be a good trend? Is still there enough time (4 dayish) for STJ to form for this area?

Link to comment
Share on other sites

I am liking this set-up for NE TX. Like always its a close call, but usually we do OK with developing Gulf lows. I have a feeling DFW may be too far west for much accum though with the cold air throughout the column there may be enough for and inch or two there. North of I-20 in NE TX I could see 1-3" with maybe a 4 or 5" amount in a sweet spot (best current guess would be around Marshall for that). 

Link to comment
Share on other sites

5 hours ago, bubba hotep said:

Basically all models showing  measurable snow for N. Texas except... The Euro. We've seen this battle before and seen the Euro win. Still, pretty tricky setup and we could see plenty of more shifts over the next couple of days.

 

24 minutes ago, aggiegeog said:

I am liking this set-up for NE TX. Like always its a close call, but usually we do OK with developing Gulf lows. I have a feeling DFW may be too far west for much accum though with the cold air throughout the column there may be enough for and inch or two there. North of I-20 in NE TX I could see 1-3" with maybe a 4 or 5" amount in a sweet spot (best current guess would be around Marshall for that). 

The 12z NAM looks dry to me other than some flurries. The ECMWF is just not on board. The problem with this is there is just no moisture. The 500mb pattern is not one that favors snow and ice here. If that little system tracking in from out west could deepen and draw up enough moisture...but unlikely given pattern, especially with Gulf low developing. Those always rob DFW of moisture and we need every bit to make this happen here.

Link to comment
Share on other sites

Agreed

20 minutes ago, DFWWeather said:

 

The 12z NAM looks dry to me other than some flurries. The ECMWF is just not on board. The problem with this is there is just no moisture. The 500mb pattern is not one that favors snow and ice here. If that little system tracking in from out west could deepen and draw up enough moisture...but unlikely given pattern, especially with Gulf low developing. Those always rob DFW of moisture and we need every bit to make this happen here.

Agreed, this looks to be an I-20 storm focused east of DFW all the way to NC. Temps will be cold enough that we should be able to make the most out of anything that does fall. The nighttime timing should also help.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...