Medium/Long Range Discussion

[Porsche]

Near Year-End Wrapup...

A brutally warm year for North America is coming to a close. December has already produced some winter highlights in the Plains States, Midwest, and portions of Quebec. Madison and Montreal were among the cities receiving substantial snowfalls. A storm is currently poised to bring a moderate to locally significant snowfall to portions of New England.

Looking ahead, the PNA is continuing to rise. The long anticipated Arctic outbreak appears likely to occur during the first week in January. Ahead of the Arctic outbreak, some snow flurries and snow showers might occur, but a big storm probably won't.

Portions of southern Canada and the eastern half of the U.S. will likely see their coldest readings of the winter so far. Some areas, perhaps including New York City, Albany, and Ottawa could see their coldest temperatures since Winter 2010-11. A subzero low in Albany and single-digit low in New York City (even with little or no snow cover) remain on the table.

However, after the Arctic outbreak, with the Arctic Oscillation likely to go positive and the EPO also likely to become positive, a period of moderation is likely to unfold, beginning in the Plains States and than spreading eastward. Unlike last winter, it does not appear that a bout of exceptional warmth is underway. More importantly, it is likely that this will be the kind of moderation that lasts about two weeks. Hence, winter will not come to an end. Moreover, January is likely to have cold monthly anomalies for perhaps the eastern two thirds of the U.S., as well as southern Ontario and southern Quebec.

Finally, the upcoming storm should not be viewed as a missed opportunity for snowfall from which lightly or non-impacted regions cannot recover. It is not a final verdict that Winter 2012-13 will continue the misery of a general absence of snowfall in those regions e.g., the Mid-Atlantic where the last snowy winter was 2009-10. There will be more opportunities for snowfall and analog cases continue to suggest that a KU-type snowstorm is not out of the question before the winter is completed.

Some hope for the New Year and beyond.

[NaoPos]

Pretty interesting to see the GFS runs all day develop some decent -NAO signals during the longer range. That because its forecasting some things in the stratosphere? or is there another driver behind that?

[tombo82685]

Pretty interesting to see the GFS runs all day develop some decent -NAO signals during the longer range. That because its forecasting some things in the stratosphere? or is there another driver behind that?

that cutter around day 11 looks like it aids to it.

[RedSky]

euro more extensive with a sauna next week, gfs somewhat tempered cooler look

[chubbs]

The euro ensemble 10-day mean hasn't changed much in past few days. Still indicates a dry mild pattern. For this to get better need to break down the SE ridge and raise heights on the west coast.

[Ralph Wiggum]

The euro ensemble 10-day mean hasn't changed much in past few days. Still indicates a dry mild pattern. For this to get better need to break down the SE ridge and raise heights on the west coast.

That's far from a mild pattern in the Northeast imho.

[pasnownut]

That's far from a mild pattern in the Northeast imho.

I was just thinking the same thing....looks zonal to me but I'm not seeing a SE ridge?

Nut

[tombo82685]

That's far from a mild pattern in the Northeast imho.

He probably meant to post the operational which shows this

[Rainshadow]

That's far from a mild pattern in the Northeast imho.

Zonal Pacific flow entering Oregon, pretty mild for January. NAEFS probability of a warmer than average week 2 up to 80-100 percent. Northern New England aside, agree with Chubbs on this.

[pasnownut]

He probably meant to post the operational which shows this

Now thats a SE ridge....and I don't like it.

Nut

[chubbs]

Zonal Pacific flow entering Oregon, pretty mild for January. NAEFS probability of a warmer than average week 2 up to 80-100 percent. Northern New England aside, agree with Chubbs on this.

yup. Not a torch - and cold air to just our north but mild for January. Good golfing weather!

[Ralph Wiggum]

He probably meant to post the operational which shows this

Agreed...."This" map is mild.

[NaoPos]

the 6z GEFS are ugly straight through. Pv gets pushed west, dumps to the mountain west states, leaving us on torch-ed side of things.

[Ralph Wiggum]

Thankfully some of us had a decent Dec 'cause January aint looking good at all right now until at least the 20th.

[chubbs]

the 6z GEFS are ugly straight through. Pv gets pushed west, dumps to the mountain west states, leaving us on torch-ed side of things.

Not unreasonable. Eventually the cold air could work east setting us up for a better back end of January. Sort of a December replay. Just one scenario.

[Rainshadow]

Not unreasonable. Eventually the cold air could work east setting us up for a better back end of January. Sort of a December replay. Just one scenario.

Not exactly the same teleconnection outlook between the op 00z gfs and 06z gfs.

Agree with second half or sometime during the second half. I think if the MJO stays alive through phase 5 there is enough motion/convection far enough east to become colder here even if it goes into the COD. The SSW or SW is still outlooked this morning and the mountain torquing is cylical. I'm guessing the latest peak is the reason for us getting colder at the end of this week.

So unless the atmosphere is going to pull a Tony Romo and throw three interceptions on above, one (or more) of them should help us down the road in January.

[LMolineuxLM1]

Not unreasonable. Eventually the cold air could work east setting us up for a better back end of January. Sort of a December replay. Just one scenario.

Only problem for sure is that with that it still screws alot of people especially DC to Trenton and Points east. With those very warm and warmer growing SST's off the the Coast its just gonna be another issue of we get screwed with mixing or rain events while 30 miles west and north get nailed with a heavy wet snow.

[tombo82685]

Not that they are always right, but the euro weeklies are hideous right through the month.

[Allsnow]

Well lets just hope February saves us

[ravensrule]

Not that they are always right, but the euro weeklies are hideous right through the month.

I am sure they will be right, but they have not been great so far this winter.

[RedSky]

wow euro weeklies resemble a january 2006 repeat. I vividly remember popup thunderstorms occuring at night in the mild humid air like it was another world, disgusting

did get the 18' snowstorm in February to partly makeup for it though

but i remember at start of december how good the weeklies looked and we know how the 3/4 that month worked out

[Mitchell Gaines]

_{From the limited preview of the weeklies I get, yup the weeklies don't bring the cold from the strat warming into the US. The result is continued warmth through the month, the winter grinch would love the weeklies today.}

[tombo82685]

Looks like their potentially, maybe a long shot, a storm around around the 6-7. Several of the gefs have something and the euro has some precip coming out of the gulf but falls apart once into VA.

[Heisy]

GM Tom Happy New year, here's to another 2-3 months of me harrassing you on facebook! LOL....As for the Jan 6-7 threat the 00z GFS started it. 6z also shows a trough just no surface reflection...Some of the individ. members show some kind of storm forming, we'll see.

[tombo82685]

GM Tom Happy New year, here's to another 2-3 months of me harrassing you on facebook! LOL....As for the Jan 6-7 threat the 00z GFS started it. 6z also shows a trough just no surface reflection...Some of the individ. members show some kind of storm forming, we'll see.

Lol ahahah Brett, I'm looking forward to it. Thats a decent looking h5 map. That trof is close to going neg tilt. Hgts would scream an exit off delmarva or va capes.

[Heisy]

Lol ahahah Brett, I'm looking forward to it. Thats a decent looking h5 map. That trof is close to going neg tilt. Hgts would scream an exit off delmarva or va capes.

yet for whatever reason they don't....12z GFS shows it but not as robust...still way out though. 84 HR NAM shows that trough beginning to enter the CONUS...maybe well get lucky and the EURO will show something.

http://mag.ncep.noaa.gov/nam/12/nam_namer_084_500_vort_ht.gif

[Ralph Wiggum]

yet for whatever reason they don't....12z GFS shows it but not as robust...still way out though. 84 HR NAM shows that trough beginning to enter the CONUS...maybe well get lucky and the EURO will show something.

http://mag.ncep.noaa.gov/nam/12/nam_namer_084_500_vort_ht.gif

Someone should start a threat thread and jinx it! Trof looks too positiv ely tilted to me and the phase, if any, happens too late. Likely another weak wave meandering off the Mid-Atl coast.

[tombo82685]

Someone should start a threat thread and jinx it! Trof looks too positiv ely tilted to me and the phase, if any, happens too late. Likely another weak wave meandering off the Mid-Atl coast.

The 12z gfs def trended away from it. Like you said the trof is to pos tilted and the s/w isn't as strong nor does it dig far enough south. The 6z probably was the best looking run imho.

[Rainshadow]

The 12z gfs def trended away from it. Like you said the trof is to pos tilted and the s/w isn't as strong nor does it dig far enough south. The 6z probably was the best looking run imho.

Last two days the 00z gfs has had a pair of what look like vapor locked runs. Wonder what has been giving it fits. 500mb pattern looks like its going to be ninaish the first half of month.

[Allsnow]

Looks like normal snowfall for Phl will be a stretch...all or nada this century