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Let's do this? First two weeks look fun in the long range.

The extended range continues to advertise a –EPO regime and yet another very stout Aleutian Ridge developing. The operational 00Z European and GFS do suggest building heights across the NE Pacific and a developing Western trough. The latest 12Z GFS does suggest a strong 1050mb Arctic High pressure cell sliding S from Western Canada into the Northern Rockies and Plains during the early December time frame. Also the CFSv2 longer range guidance has been flip flopping from a warmer pattern to a colder pattern across Canada and the Lower 48. There is an anomalous warm pool of sea surface temperatures across the N Pacific Ocean and as we have just witnessed we can see some colder weather in such a synoptic pattern. The $64,000 question is will there be sub tropical moisture in place as the cold shallow Arctic air mass sinks south. We will see.

Nice graphics, sir. Suspect we'll have a lot to talk about in the days ahead.

Sorry for anyone in south central or southeast Texas who expected a winter storm out of this system with "wintry" precip, but hey ... considering where we are in the calendar, this current weather event is pretty amazing. We're looking at 30-degree-below-normal temps for this time of year. That's unusual.

Ed Mahmoud wrote:New op GFS not exciting, and remember, cold without precip is just unpleasant. GFS does have a light freeze this week, which is still November, nothing with scares me, however.

This is true ... however ... I think it bears mention that the 12z GFS operational run to which you refer is not in sync with the GFS ensembles, the Euro ensembles, the last several cycles of the Euro operational, and the NCEP super ensembles. In other words, it's worthless.

Bastardi yesterday on Twitter indicated that the longer range computer models are suggesting a pattern ahead much like December 1983. And we all should remember what that one did to south central and southeast Texas. Seems a bit extreme to me, but so is the current weather we're experiencing. So, who knows.

Yep... I'd love a December 1983 or 1989.

1983 was a power system that froze the coast.

Portastorm wrote:

Ed Mahmoud wrote:New op GFS not exciting, and remember, cold without precip is just unpleasant. GFS does have a light freeze this week, which is still November, nothing with scares me, however.

This is true ... however ... I think it bears mention that the 12z GFS operational run to which you refer is not in sync with the GFS ensembles, the Euro ensembles, the last several cycles of the Euro operational, and the NCEP super ensembles. In other words, it's worthless.

Bastardi yesterday on Twitter indicated that the longer range computer models are suggesting a pattern ahead much like December 1983. And we all should remember what that one did to south central and southeast Texas. Seems a bit extreme to me, but so is the current weather we're experiencing. So, who knows.

December 1983 and 1989 freezes are outliers like February 1895 and 1899 freezes.

Very impressive looking cold pattern developing for early December via the overnight guidance if they are correct.

BWAHAHAHAHA (Evil laugh)... Did anyone see the 10 day Euro Ensemble Run?

Record breaking would be a phrase that would come to mind.

I'm with you, Ed. I like my plants and pipes. Go figure.... I was around to endure frozen pipes in both 83 and 89. Careful what we wish for. I remember brown oleanders. Brown... Oh well, nothing to do but watch and see. I would love for the rain trend to continue. I saw we could get more rain next week but nothing too cold. Highs in 60s?


Don't get me wrong. I'm loving this cold weather and hope it's cooler than normal this winter. Just not 83, 89

Can someone tell me what the long range models show? Temperature-wise?

vci_guy2003 wrote:Can someone tell me what the long range models show? Temperature-wise?

It is way too soon to know the 'finer details' such as temperature we may see during the second week of December this far out, but the ensembles generally agree that a strong Arctic boundary will settle into the Western US and Great Basin next week that will plummet temps to 20+ below normal across the Pacific NW/Great Basin and Northern Rockies and a secondary surge of much colder air will drop S across Canada and settle into the Western 2/3rds of North America as far south as Mexico and points W of the Mississippi River Valley during the second week of December. There are rather strong indications that the coldest air of all the Northern Hemisphere will be located on our side of the world, so it will be worth monitoring. Happy Thanksgiving everyone from Srain's house to yours.

I am becoming increasingly interested in the medium range for our Region as the operational and ensemble guidance continue to advertise a synoptic pattern favorable for moisture and anomalously cold air developing across the Pacific NW into the Great Basin/Northern Rockies extending into the Northern/Central Plains. The wild card will be just how much of a snow cover can be established across the Plains and the eventual storm tracks with an Arctic air mass firmly entrenched before a secondary surge of Arctic air pushes further E and S into the Southern Rockies and Southern Plains. As we have just witnessed, even a +AO that briefly dipped into slightly negative territory and a slightly +PNA can deliver some very chilly air very far S into Texas and Mexico, so it will be interesting to see if we see some MJO tropical forcing begin to interact with increased sub tropical jet moisture beyond the medium range time frame. It does appear that our source Regions will have abundant cold air to work with as well. All that is lacking appears to be snow cover across the Plains that would tend to guarantee less air mass modification during the second week of December.

srainhoutx wrote:I am becoming increasingly interested in the medium range for our Region as the operational and ensemble guidance continue to advertise a synoptic pattern favorable for moisture and anomalously cold air developing across the Pacific NW into the Great Basin/Northern Rockies extending into the Northern/Central Plains. The wild card will be just how much of a snow cover can be established across the Plains and the eventual storm tracks with an Arctic air mass firmly entrenched before a secondary surge of Arctic air pushes further E and S into the Southern Rockies and Southern Plains. As we have just witnessed, even a +AO that briefly dipped into slightly negative territory and a slightly +PNA can deliver some very chilly air very far S into Texas and Mexico, so it will be interesting to see if we see some MJO tropical forcing begin to interact with increased sub tropical jet moisture beyond the medium range time frame. It does appear that our source Regions will have abundant cold air to work with as well. All that is lacking appears to be snow cover across the Plains that would tend to guarantee less air mass modification during the second week of December.

A negative East Pacific Oscillation (EPO) can give cold air even when NAO and AO are positive. The December 1983 and February 1989 Freeze occurred during a positive NAO and AO, but negative EPO. The February 1989 Freeze had a strong positive NAO and AO.

http://www.crh.noaa.gov/dtx/winter_2002 ... php#eponao

Being a lifelong student of meteorology is a great thing ... and all of us here sit in that classroom. Personally, I've learned a lot already this month about just how strongly the Pacific teleconnections impact our weather here in south central (and southeast) Texas. Even though the Arctic Oscillation (AO) and North Atlantic Oscillation (NAO) have been primarily positive -- which usually means warmer conditions -- the Eastern Pacific Oscillation (EPO) has overwhelmed those signals and that, combined with ridging in the North Pacific/Alaska, has helped keep us cold and stormy in the last two weeks.

The Madden-Julian Oscillation (MJO) looks to remain in the 8-1-2 octants which suggests colder than normal and wetter than normal conditions for Texas. The strength of the MJO signal doesn't appear too strong though so the MJO's impact may be minimal. I know enough about this stuff to be dangerous!

1983 was many days of freezing temps combined with drizzle. No snow fell except for, I believe Lakeview. Older brother and I were fired up when we watched the noon news before the cold air marched south.
It was a Christmas break I'll never forget. One for the freezing temps. Two for the letdown that all that cold left not one snowflake to be seen. Believe our heater also broke, which left us burning just about everything in the fireplace.

I'm not seeing anything like 1983 or 1989. Here's a plot of the 12Z GFS forecast temps (valid 6am and 6pm). Lows near freezing and a high in the 40 deg range next Sunday with some rain around. Very much like this week was. A quick warm-up on Tuesday followed by another cold front then another quick warm-up.

00Z GFS making anybody else chuckle tonight with temperatures and snow accumulation totals?

I see nothing in last night's GFS to indicate any frozen precip or very cold temps here through 15 days. I do see temps near 80 next week and then a light freeze next weekend (no precip).

Nice-looking meteograms, wxman57! I highly doubt they'll verify but nice-looking nevertheless.

No sir, one operational run of a somewhat poorly performing computer model will not save you from the coming winter apocalypse. Teleconnections and model ensembles point to a colder, stormier southeast Texas than what this shows.

Joe mentions 1983/1989 or 1899 every year. I started reading him back in 99/2000 and even back then, he would bring out the 'ghost of 1899' every time he saw cross polar flow being setup. The chances of us seeing such an extreme event in any given season is extremely low.