December and a Hint of January Pattern Discussion

[Bob Chill]

Exactly.  And that's what everyone needs to remind themselves of every time the pattern doesn't look good.  The long range has done this several times this season already, yet, we've had no real warmups and have had some pretty decent early winter weather.

 

Pattern is less good and trending in that direction but it's far from bad. SW's embedded in the flow post xmas have zero resolution at this lead so no panic buttons. If anything, I could easily see there being ops with the setup but they will be ns dominant. Fine with me. Anything beats pac zonal like last year.

 

GFS has a sub 1000mb lp entering IN on Sunday. This op run will have zero friends on the ec. 

[WinterWxLuvr]

Lots of uncertainty in the ensembles, IMO.

[WxUSAF]

12z GEFS pretty robust with a +PNA from days 8-14 or so.  Looks northern stream dominated.  Raging +NAO of course.    

[WxUSAF]

Today's Euro looks like it takes the cutter farther south/east, and I'd guess it doesn't torch us all the way to Ian's liking.  

[Ian]

Today's Euro looks like it takes the cutter farther south/east, and I'd guess it doesn't torch us all the way to Ian's liking.  

Might be making a last minute journey to Ft Lauderdale for Christmas so I can root less for a torch locally. 

[Heisy]

I'm salivating at this setup here. You guys know me, I'm always living in the future, it's a curse. 

 

1- SE ridge has moved farther East

2- PNA spike

3- 50/50?

4- Larry Cosgrove storm? 

 

[WxUSAF]

Might be making a last minute journey to Ft Lauderdale for Christmas so I can root less for a torch locally. 

Just based off the free images I see of the Euro, I'd guess it's seasonable or a little below normal for Christmas day.  Certainly looks like a brown Christmas locally right now.  

[WxUSAF]

I'm salivating at this setup here. You guys know me, I'm always living in the future, it's a curse. 

 

1- SE ridge has moved farther East

2- PNA spike

3- 50/50?

4- Larry Cosgrove storm? 

 

goodlook.gif

Maybe.  Pac certainly looks good.  If the confluence can stick around the Lakes and NE, that might be a nice overrunning situation.  But, it looks more likely to me to be getting ready for another big cutter with the big Bermuda ridge off the East Coast and +NAO.  

[WxUSAF]

Today's Euro looks like it takes the cutter farther south/east, and I'd guess it doesn't torch us all the way to Ian's liking.  

Maybe not.  Wunderground looks like upper 50s Friday, low 60s Saturday, near 70 for Sunday and then a midnight high for Monday in the 60s probably.  

[Bob Chill]

GEFS definitely hint at the -epo reloading d11-15. Optimistic thought of the day. I'm waiting for the euro ens to finish posting on wxbell. They don't look bad through d10. We're gonna get real warm for at least 2 days. I don't think we can avoid that. Euro ens take the front through sometime on Monday.

[Fozz]

GEFS definitely hint at the -epo reloading d11-15. Optimistic thought of the day. I'm waiting for the euro ens to finish posting on wxbell. They don't look bad through d10. We're gonna get real warm for at least 2 days. I don't think we can avoid that. Euro ens take the front through sometime on Monday.

 

As long as it's just a few days, I'm ok with it, even if it melts my snow.

 

I know back in 2009-10, even after the amazing -AO/NAO from December relaxed, forecasters like Don S. could just tell that it was going to reload later that winter since those patterns tend to recur.

 

Does the EPO work the same way? This could be a great winter for many of us if it reloads and stays that way for much of the winter (hopefully with a storm track that will include DC more, though I think that will depend on a southern stream and of course a better Atlantic).

[WEATHER53]

Larry is going for big cold right at the end of the year. We really do not have a winter southeast ridege but we are getting some push back from the atlantic as exampled by new york being able to be much colder than DC.

[Bob Chill]

As long as it's just a few days, I'm ok with it, even if it melts my snow.

 

I know back in 2009-10, even after the amazing -AO/NAO from December relaxed, forecasters like Don S. could just tell that it was going to reload later that winter since those patterns tend to recur.

 

Does the EPO work the same way? This could be a great winter for many of us if it reloads and stays that way for much of the winter (hopefully with a storm track that will include DC more, though I think that will depend on a southern stream and of course a better Atlantic).

 

I'm not well versed with the epo at all. I started looking at historical daily data It's all over the place to be honest. Some years are biased with relaxation and reload from door to door. Others are outright flips. 

 

From what I've been read, the epo is quite likely to remain favorable due to the substantial + SST anoms in the gulf of alaska. Higher heights in that region should remain in the overall longwave pattern for the foreseeable future and beyond. Whether the ridging builds poleward is a different issue. But it's very encouraging to have the pac on our side in general considering the atlantic is pretty much a disaster. Pac zonal is still cutoff through the end of the month at the very least. 

 

Euro looks fine in the means and dailies from xmas through the end of the run. Mean trough axis centered over the lakes throughout the period. PV centered northern hudson bay.  WC ridging is predominant with the coldest temp anomalies relative to normal in our general vicinity with NE being the coldest. It's not a frigid look but far far from a terrible pattern. 

 

NAO remains positive (shocker) but there signs of some heights building over the pole region. Especially on the euro. 

 

here's d11-15 5h mean. There's good and bad here but imo I think it's pretty darn good for the sole reason that winter isn't canceled and things can progress very favorable from here:

 

 

 

There are some signs emerging that the mega +AO is running out of gas towards the end of the month. If we can block the progressive flow and just have a +pna it would be great. Block the flow with a good -epo ridging and I think we would be very cold here. Add split flow and weenies will be doing naked jumping jacks. 

[Ji]

Larry is going for big cold right at the end of the year. We really do not have a winter southeast ridege but we are getting some push back from the atlantic as exampled by new york being able to be much colder than DC.

Of course we have a se ridge

[WEATHER53]

Of course we have a se ridge

Not the typical winter time one that keeps DCA on the warm side.

[Bob Chill]

Christmas eve miracle coastal. happy hour does it again. 

[usedtobe]

Christmas eve miracle coastal. happy hour does it again. 

Let's hope as the overall pattern still is a bad one. I just got back from the NCEP/WPC party and we snow lovers were lamenting at the pattern for the I95 group.  The problem with the xmas miracle storm is if it ramps up and actually comes north enough to really get us we might end up even warmer as the low up in the lakes region does its stuff.  We don't want phasing but want the wave to pull precip just enough north of clip us.  Could it happen, sure but still has a lot working against it. 

 

Even the Euro ens mean now has sunday torching and doesn't bring the cold in until Monday and then it's only normal winter cold, nothing exceptional.  This dec is going to end up almost normal in terms of temps as we will be above normal after sunday. 

[Bob Chill]

Wes, I have zero confidence in the xmas eve storm. It's the first look we've seen of a trailing wave and it is the 18z gfs after all....my post was in jest for the most part. 

 

A wave could definitely happen. We have a torch and a rainstorm to endure first. I'm not really all that interested in the pre xmas period but I'll watch because that's what I do.

 

The final week of the month does look cool but not cold. Just being near normal in late december is fine. Pretty nice +pna look and ok trough axis. At the very least snow isn't impossible. 

 

I do like the early signs of the -epo coming back. And the +ao does finally appear to break down for real. Hard to say if a -ao is in the cards but the days of +2 or more seem to be coming to a close. 

[WinterWxLuvr]

Wes, I have zero confidence in the xmas eve storm. It's the first look we've seen of a trailing wave and it is the 18z gfs after all....my post was in jest for the most part.

A wave could definitely happen. We have a torch and a rainstorm to endure first. I'm not really all that interested in the pre xmas period but I'll watch because that's what I do.

The final week of the month does look cool but not cold. Just being near normal in late december is fine. Pretty nice +pna look and ok trough axis. At the very least snow isn't impossible.

I do like the early signs of the -epo coming back. And the +ao does finally appear to break down for real. Hard to say if a -ao is in the cards but the days of +2 or more seem to be coming to a close.

Where do you suppose the trough axis is? I think that's a big key. Get that thing too far east and you get cold, windy, and partly cloudy.

[Bob Chill]

Where do you suppose the trough axis is? I think that's a big key. Get that thing too far east and you get cold, windy, and partly cloudy.

 

It's not deep so suppression isn't a worry. Especially without a block. PV is centered just nw of hudson bay on all ens now for the last week of the month. This is just one day of the 18z gefs but it looks the same as everything else. Nothing classic here but you can't say it can't snow.

 

[Wonderdog]

Wes, I have zero confidence in the xmas eve storm. It's the first look we've seen of a trailing wave and it is the 18z gfs after all....my post was in jest for the most part. 

 

A wave could definitely happen. We have a torch and a rainstorm to endure first. I'm not really all that interested in the pre xmas period but I'll watch because that's what I do.

 

The final week of the month does look cool but not cold. Just being near normal in late december is fine. Pretty nice +pna look and ok trough axis. At the very least snow isn't impossible. 

 

I do like the early signs of the -epo coming back. And the +ao does finally appear to break down for real. Hard to say if a -ao is in the cards but the days of +2 or more seem to be coming to a close. 

I think the Christmas eve coastal showed up about four days ago and then disappeared until today. That stalled front has been shown for  few days now. I like stalled fronts.

[snow.]

Let's hope as the overall pattern still is a bad one. I just got back from the NCEP/WPC party and we snow lovers were lamenting at the pattern for the I95 group.  The problem with the xmas miracle storm is if it ramps up and actually comes north enough to really get us we might end up even warmer as the low up in the lakes region does its stuff.  We don't want phasing but want the wave to pull precip just enough north of clip us.  Could it happen, sure but still has a lot working against it. 

 

Even the Euro ens mean now has sunday torching and doesn't bring the cold in until Monday and then it's only normal winter cold, nothing exceptional.  This dec is going to end up almost normal in terms of temps as we will be above normal after sunday. 

 

The pattern looks bad for the next 2 weeks...very nina like with a storm track to our west right up the Ohio valley...

[snow.]

I'm salivating at this setup here. You guys know me, I'm always living in the future, it's a curse. 

 

1- SE ridge has moved farther East

2- PNA spike

3- 50/50?

4- Larry Cosgrove storm? 

 

goodlook.gif

 

anything in that pattern would cut to our west,,,even with the PNA spike...

[snow.]

70 on sunday??

[aldie 22]

I hope the warm weather days are drowned in rain

[Kevin Druff]

The pattern looks bad for the next 2 weeks...very nina like with a storm track to our west right up the Ohio valley...

This is pretty much what I told the Richmond folks over on Facebook in our chat... In fact, I was even a bit more pessimistic and said I think we're punting until 1/15 at the earliest.

It's funny. We've had so many "near misses" and relative cold, that it feels like it should be mid-January instead of only mid-December. Punting 3-4 weeks on 12/15 certainly doesn't hurt as much as it would on 1/15.

[snow.]

This is pretty much what I told the Richmond folks over on Facebook in our chat... In fact, I was even a bit more pessimistic and said I think we're punting until 1/15 at the earliest.

It's funny. We've had so many "near misses" and relative cold, that it feels like it should be mid-January instead of only mid-December. Punting 3-4 weeks on 12/15 certainly doesn't hurt as much as it would on 1/15.

 

Not sure about that....still a tricky changeable pattern...but for me and you...if we lose our cold air source, and don't have a block and lose the southern stream...I'm not too confident...a gradient pattern is bad for me and you...as long as heights w/respect to normal are lower to our north than they are here and to the south, we aren't getting a good storm track...the low anomaly to our north pretty much guarantees storms will cut west...next 10 days or so look warm and uneventful to me...after Christmas,  i dont  know...this has been a hard pattern to nail down

[Bob Chill]

Matt, keep an eye on heights around the pole. I'm seeing signs of a reshuffle. We may get some kind of jacked up ridging pushing down from the pole into the nao region instead of it poking into gl from the Atlantic. Not sure I'm describing it correctly but there are signs of significant changes compared to the sick +ao we've had for what seems like forever.

Epo may reload as well. I agree with your Nina look comment but Xmas week is a ways off and ensembles are all over the place except for the pna ridge. Seeing so many varied solutions is a harbinger of a sig pattern change and none of it looks terrible. Well, not terrible after we get a good tan for a couple days.

[HM]

The pattern looks bad for the next 2 weeks...very nina like with a storm track to our west right up the Ohio valley...

 

Meh, it's a temporary nina look really. Take a look at a wv loop...giant low in E PAC with split flow. This thing comes east, phases with PJ for Midwest system later this week. When that baroclinic zone gets to the coast 12/23-24, it has to be watched (even though models are quiet for now). The PNA pattern returns thereafter. The hybrid nature continues...

[snow.]

Meh, it's a temporary nina look really. Take a look at a wv loop...giant low in E PAC with split flow. This thing comes east, phases with PJ for Midwest system later this week. When that baroclinic zone gets to the coast 12/23-24, it has to be watched (even though models are quiet for now). The PNA pattern returns thereafter. The hybrid nature continues...

 

thanks...you have done really well with the hybrid nature of the pattern...I just get frustrated because I know what it means for my backyard....and ultimately that is where I forecast...I know you know this, but the snow gradient here is not that uncommon for December...it is a bit more of an extreme example this year, but to have heavy snow amounts roughly NW of a line from Leesburg to Frederick to Westminster (I know the N/NW Baltimore burbs did well too) versus southeast of that line has happened quite a bit.....The majority of DC metro has 1-5" this winter so far....probably <4" for most..I have 1.5"..climo for DEC.......I know you speak to a much broader area and to larger scale ideas than I do, but if a storm gives York PA, 6-10" and gives me 1", it doesn't mean a lot to me...we in DC are lone wolves......I give you mad props if a storm can develop in your window, and I am pretty confident it will nail 40N and give me 0.25"