November Weather Discussion. Rollercoaster Pattern.

[srainhoutx]

Looking at the overnight Euro Ensembles suggest a strong blocking pattern that drops the cold air S out of Canada...

500mb Amomalies



850mn Temp Anomalies...

[Andrew]

I was talking to a buddy of mine and he said that a long range model he was looking at showed some sort of frozen precip for early December. I don't know which model he was looking at or which model even goes that far out but should be interesting to note that December could be interesting as the setup continues to show some artic blasts. I'll invest this some more when I get home.

[wxman57]

I was talking to a buddy of mine and he said that a long range model he was looking at showed some sort of frozen precip for early December. I don't know which model he was looking at or which model even goes that far out but should be interesting to note that December could be interesting as the setup continues to show some arctic blasts. I'll invest this some more when I get home.

There is only one long-range model that reaches early December, that's the GFS. No GFS run has predicted snow for our area in early December. Those graphics with temps and precip areas can be very misleading, as the two aren't happening at the same time on the graphic. The precip occurs sometime during the 12 hours PRIOR to the graphic with the freezing line near us. The precip will end just as the cold front moves through but the graphic will indicate precip and cold air at the same time.

Note that I do have Dec. 4th as my date for the first freeze at IAH this year in the office pool. How did I arrive at that date? I have all dates from early Nov through the first week of January in a small bowl. For 20 years I've tried to win these office pools, making careful analyses and climatological outlooks only to lose to the office receptionist who knows nothing about meteorology. I've come closer picking dates out of a bowl.

Speaking of the GFS, the 12Z run is considerably "warmer" than the 00Z run for Thanksgiving week:

[srainhoutx]

Well the 12Z Euro hasn't 'warmed up'...

[Andrew]

I was talking to a buddy of mine and he said that a long range model he was looking at showed some sort of frozen precip for early December. I don't know which model he was looking at or which model even goes that far out but should be interesting to note that December could be interesting as the setup continues to show some arctic blasts. I'll invest this some more when I get home.

There is only one long-range model that reaches early December, that's the GFS. No GFS run has predicted snow for our area in early December. Those graphics with temps and precip areas can be very misleading, as the two aren't happening at the same time on the graphic. The precip occurs sometime during the 12 hours PRIOR to the graphic with the freezing line near us. The precip will end just as the cold front moves through but the graphic will indicate precip and cold air at the same time.

Note that I do have Dec. 4th as my date for the first freeze at IAH this year in the office pool. How did I arrive at that date? I have all dates from early Nov through the first week of January in a small bowl. For 20 years I've tried to win these office pools, making careful analyses and climatological outlooks only to lose to the office receptionist who knows nothing about meteorology. I've come closer picking dates out of a bowl.

Speaking of the GFS, the 12Z run is considerably "warmer" than the 00Z run for Thanksgiving week:

http://myweb.cableone.net/nolasue/iah12znov16.gif

Thanks Wxman I was questioning where he saw this but as we all know A LOT can change between now and then.

Also srain that does look cold. Western Canada looks to be FREEEEEZING!

[helloitsb]

Here's an extended range GFS meteogram for IAH. Note that it's the predicted 2 meter temps for 6am and 6pm each day - NOT the lows/highs for each day. However, the 6am temp will be close to the low of the day. The 6pm temp will occur 4 hours after the daily high, so you have to add another 5-7 degrees (sunny day) to get close to the high temp.

I know you have come out with another chart but does this chart show that for Thanksgiving we would have a high for a low and a low for a high? Gradual cooling throughout the day?

[srainhoutx]

Here's an extended range GFS meteogram for IAH. Note that it's the predicted 2 meter temps for 6am and 6pm each day - NOT the lows/highs for each day. However, the 6am temp will be close to the low of the day. The 6pm temp will occur 4 hours after the daily high, so you have to add another 5-7 degrees (sunny day) to get close to the high temp.

I know you have come out with another chart but does this chart show that for Thanksgiving we would have a high for a low and a low for a high? Gradual cooling throughout the day?

There are some differences between the models on when the Arctic front will arrive. The Euro is faster and the GFS is slower by about 12-18 hours. As we get closer to next week, things should begin to come in better agreement. Stay Tuned.

[wxman57]

Here's an extended range GFS meteogram for IAH. Note that it's the predicted 2 meter temps for 6am and 6pm each day - NOT the lows/highs for each day. However, the 6am temp will be close to the low of the day. The 6pm temp will occur 4 hours after the daily high, so you have to add another 5-7 degrees (sunny day) to get close to the high temp.

http://myweb.cableone.net/nolasue/meteogram.gif

I know you have come out with another chart but does this chart show that for Thanksgiving we would have a high for a low and a low for a high? Gradual cooling throughout the day?

The GFS forecast (link above) does show a 6am Thanksgiving temp of 69 and the temperature falling through the day to 49 by 6pm and 33 by 6am Friday. However, the 12Z GFS now shows temps holding in the upper 60s all day Thanksgiving with a weaker front coming in Thursday night. Bottom line is it's way too early to be very confident in next week's forecast.

[Mr. T]

Anyone notice this on the E-Wall site?

http://www.meteo.psu.edu/~gadomski/ECMW ... floop.html

The Euro goes out to day 10 now. w00t.gif

[wxman57]

Anyone notice this on the E-Wall site?

http://www.meteo.psu.edu/~gadomski/ECMW ... floop.html
The Euro goes out to day 10 now. w00t.gif

Hadn't noticed - good catch! The link is atop the "normal" 168hr Euro only on the US sectional.

Note that the Euro is now slower with the cold air coming down, and it's also has another short wave rotating around the top of the ridge at day 10. This could bring some very cold air in south-central Canada south into the U.S. the weekend after Thanksgiving, and eventually here.

[srainhoutx]

Oh my...it is the 18Z GFS though...

[biggerbyte]

Wow! That would be happy fun...No?

La Nina could get her warm, dry tail frozen off. Lol
She may even get it wet.

Brrrr..

[extremeweatherguy]

The 18z GFS is definitely one of the colder runs I have seen of late, but it might not be all that far-fetched. Several waves of cold are looking more and more likely to roll into the USA starting Thanksgiving week and lasting through (at least) the end of the month. I wouldn't at all be surprised to see a widespread freeze reach all the way south into southeast Texas before the start of December. Up here in Oklahoma where I'm at, we might even see teens before the end of the month. It's definitely going to be interesting to watch play out!

Unfortunately, (or fortunately depending on your perspective), it looks like this swing towards colder will likely not last all winter. It might keep up through December, but by January into February it looks like warmer and drier will be the rule across the southern plains. So, if you're a winter-lover, the next 4-6 weeks is your time to enjoy!

[helloitsb]

The 18z GFS is definitely one of the colder runs I have seen of late, but it might not be all that far-fetched. Several waves of cold are looking more and more likely to roll into the USA starting Thanksgiving week and lasting through (at least) the end of the month. I wouldn't at all be surprised to see a widespread freeze reach all the way south into southeast Texas before the start of December. Up here in Oklahoma where I'm at, we might even see teens before the end of the month. It's definitely going to be interesting to watch play out!

Unfortunately, (or fortunately depending on your perspective), it looks like this swing towards colder will likely not last all winter. It might keep up through December, but by January into February it looks like warmer and drier will be the rule across the southern plains. So, if you're a winter-lover, the next 4-6 weeks is your time to enjoy!

Love the cold weather, wish things would work out perfectly to get some snow or some sort of frozen precip. I know its far fetched but it would make my winter, it can be warmer and more dry the rest of winter if we would get some snow I wouldn't mind

[Andrew]

The 18z GFS is definitely one of the colder runs I have seen of late, but it might not be all that far-fetched. Several waves of cold are looking more and more likely to roll into the USA starting Thanksgiving week and lasting through (at least) the end of the month. I wouldn't at all be surprised to see a widespread freeze reach all the way south into southeast Texas before the start of December. Up here in Oklahoma where I'm at, we might even see teens before the end of the month. It's definitely going to be interesting to watch play out!

Unfortunately, (or fortunately depending on your perspective), it looks like this swing towards colder will likely not last all winter. It might keep up through December, but by January into February it looks like warmer and drier will be the rule across the southern plains. So, if you're a winter-lover, the next 4-6 weeks is your time to enjoy!

Where did you get the January/ February info?

[wxman57]

The 18z GFS is definitely one of the colder runs I have seen of late, but it might not be all that far-fetched. Several waves of cold are looking more and more likely to roll into the USA starting Thanksgiving week and lasting through (at least) the end of the month. I wouldn't at all be surprised to see a widespread freeze reach all the way south into southeast Texas before the start of December. Up here in Oklahoma where I'm at, we might even see teens before the end of the month. It's definitely going to be interesting to watch play out!

Unfortunately, (or fortunately depending on your perspective), it looks like this swing towards colder will likely not last all winter. It might keep up through December, but by January into February it looks like warmer and drier will be the rule across the southern plains. So, if you're a winter-lover, the next 4-6 weeks is your time to enjoy!

Where did you get the January/ February info?

Such outlooks are based upon analog years, primarily. Though the ECMWF long-range forecast for Dec-Feb is for significantly above normal temps across Texas and the Deep South.

[srainhoutx]

Interesting comment from HM, a respected Long Range Met on Americanwx...

Yeah this is going to potentially set up a reverse warm anomaly for many in the northern 2/3s of the CONUS, outside of maybe the NW, for a 6-10 day period. As the MJO composites suggest, a phase 3-4-5 transition from where we are now would bring quite an impressive warm shot, outside of the southern states. Once the -NAO block is finished and the EPO goes significantly positive (as wavelengths become longer from both being a winter seasonal progression and the -NAO block going away), it is going to get ugly. At some point in late December, I expect a classic cold Northwest/North regime to return and the ridge to properly place over the Southeast. This classic regime looks to get heightened in early January, possibly setting off some serious storm systems across the Central States!

[weatherguy425]

So he's expecting a "reverse warm anomaly " in the short term?

[srainhoutx]

So he's expecting a "reverse warm anomaly " in the short term?

Remember that wxman57 also stated a 'above average' December. After this early season chill, a warm up looks to occur as the pattern reloads. And for those wondering, the snowpack is doing just fine in Siberia.

[extremeweatherguy]

The 18z GFS is definitely one of the colder runs I have seen of late, but it might not be all that far-fetched. Several waves of cold are looking more and more likely to roll into the USA starting Thanksgiving week and lasting through (at least) the end of the month. I wouldn't at all be surprised to see a widespread freeze reach all the way south into southeast Texas before the start of December. Up here in Oklahoma where I'm at, we might even see teens before the end of the month. It's definitely going to be interesting to watch play out!

Unfortunately, (or fortunately depending on your perspective), it looks like this swing towards colder will likely not last all winter. It might keep up through December, but by January into February it looks like warmer and drier will be the rule across the southern plains. So, if you're a winter-lover, the next 4-6 weeks is your time to enjoy!

Where did you get the January/ February info?

As wxman57 pointed out, the idea of a warmer and drier January/February is based on analog years and the fact that we are going to be in a La Nina winter. Generally, similar winters in the past have proven warmer-than-normal and drier-than-normal overall across the southern plains. Several of the seasonal forecast models including the CFS and ECMWF are also backing these ideas.

Now of course, while it should average out to be warmer and drier overall; there could still very well be a few significant cold snaps in the January and February timeframe. They will likely be fewer and farther between than usual; but that doesn't mean that they will be any less significant cold-wise when they do manage to make it into the southern plains.