12/04. 12z. GFS

[MDstorm]

Horrible run. Cold and dry for the next 10 days......then a Lakes cutter.....then cold and dry.

MDstorm

[MDstorm]

I'll try to keep the faith, but the pattern seems to want to amplify things to far north and east over the next 2 weeks (except for the cutter).

Dont worry with the pattern we are going into to here then next couple of weeks, its perfect for one of those lows to become a big storm on the coast. Dont worry. Plus the NAO is going to stay negitive.

[aldie 22]

I'll try to keep the faith, but the pattern seems to want to amplify things to far north and east over the next 2 weeks (except for the cutter).

Don't be too concerned about a lakes cutter at hour 330. The pattern as shown is cold with what looks like a few clippers rolling down. Miller B fest which isn't good for our area usually but would probably give us some snow but the folks up the coast quite a bit more. Who knows though as the models certainly haven't gotten a good handle on the pattern in the longer range

[clskinsfan]

The long range models have been all over the place. They cant seem to lock down storms outside of 3 days out. The cold is what we need for snow and it looks like we are going to have that.

[Dr No]

It's going to be cold for at least the next 10 days... just a matter of waiting for things to relax enough to allow a storm to have a chance east of the Rockies.

[usedtobe]

A few thoughts on the pattern. It does looks like cold and dry is the most likely scenario over the next 10 plus days. The GFS superensemble mean centered on Dec 15th only picks up one day in 10 that DCA got over an inch within 5 days of the centered mean. That suggests that the chances of picking up an inch is no better than climo despite the negative NAO. We're reduced to hoping that a clipper will track prefectly to get us. The GFS did look interesting at 192 hrs at both 500mb and at the surface making it look like we might have a chance.

But it crushes it and shears it south of us.

There remain two features that the models are confident in forecasting, the blocking near Greenland and the reverse PNA pattern in the Pacific. This two features tend to work in opposition. The negative PNA means that most losws that form will form to the lee of the mountains at a fairly high latitude so when the they don't get crushed by the NAO blocking, the lows tend to track towards the great lakes. The NAO says wait a minute and tries to make them into miller b type system or clippers. You can sort of see that on the ensemble members below.

Does all the above mean that we won't see a significant snowstorm. No, but it means that the odds of a big one in this area remains low and probably no better than climo through Dec 15 maybe even dec 18. Until then, we're probably reduced to hoping for clippers and having a perfect track. Not impossible but always tricky to see much in advance.

[ozzie]

the storm around hour 228 looks fairly large although it is off the coast a bit. I think this is a miller B as well correct?

[usedtobe]

the storm around hour 228 looks fairly large although it is off the coast a bit. I think this is a miller B as well correct?

If it were to go up the coast it might be. Miller bs tend to track into the OH valley or Great Lakes region and then reform along the atlantic coast.

[mdsnowlover]

why are all the storms forming so far out to sea?? Is this where the baroclinic zone has set up this year???

[WinterWxLuvr]

A few thoughts on the pattern. It does looks like cold and dry is the most likely scenario over the next 10 plus days. The GFS superensemble mean centered on Dec 15th only picks up one day in 10 that DCA got over an inch within 5 days of the centered mean. That suggests that the chances of picking up an inch is no better than climo despite the negative NAO. We're reduced to hoping that a clipper will track prefectly to get us. The GFS did look interesting at 192 hrs at both 500mb and at the surface making it look like we might have a chance.

But it crushes it and shears it south of us.

There remain two features that the models are confident in forecasting, the blocking near Greenland and the reverse PNA pattern in the Pacific. This two features tend to work in opposition. The negative PNA means that most losws that form will form to the lee of the mountains at a fairly high latitude so when the they don't get crushed by the NAO blocking, the lows tend to track towards the great lakes. The NAO says wait a minute and tries to make them into miller b type system or clippers. You can sort of see that on the ensemble members below.

Does all the above mean that we won't see a significant snowstorm. No, but it means that the odds of a big one in this area remains low and probably no better than climo through Dec 15 maybe even dec 18. Until then, we're probably reduced to hoping for clippers and having a perfect track. Not impossible but always tricky to see much in advance.

Several of those members, it would seem, show pretty good storms. I thought the time period around a week from now looked pretty good, cold and the trof axis a little further west. I don't have much faith in these models beyond about 48 hours for anything specific, but it would seem they are fairly confident of one main ingredient needed, and that is cold.

[usedtobe]

why are all the storms forming so far out to sea?? Is this where the baroclinic zone has set up this year???

Well this clipper just didn't have room because of the vortex over NY and New England ahead of it. The 192 hour system runs into a similar deal but it's 192 hours in the future and one thing I didn't mention and meant to is that the ensemble members often in the longer ranges don't have enough spread so a storm that doesn't shear as much and reforms closer to the coast is a possibility especially for those guys living north of us. Heck, at those time ranges, the a storm could always pop up and make JB look like a hero.

[Dr No]

The GFS has out-performed the Euro pretty well. I don't think the Euro knows what to do with Atlantic blocking. The model seemed to be king in a +NAO regime.

[ozzie]

speaking of the euro does anyone know what the latest euro shows for its long range?

[usedtobe]

speaking of the euro does anyone know what the latest euro shows for its long range?

I looked at the euro and it gives us no measureable snow through day 10. It takes a low into the great lakes at 144 hrs, gives us rain with the associated front at 168 with the 850 temps too warm for snow for I95. By 192 hrs that front is well off the coast at our latitude, it does form a low on the front off the southeast coast but it shifts too far east to give us anything. at 240 hours it again has an amped up trough in the east but based on its performance recently, tit is probably too amplified with its troughs this year or at least to me it has seemed to.

[usedtobe]

Several of those members, it would seem, show pretty good storms. I thought the time period around a week from now looked pretty good, cold and the trof axis a little further west. I don't have much faith in these models beyond about 48 hours for anything specific, but it would seem they are fairly confident of one main ingredient needed, and that is cold.

But if you look closely the storm ones are too far north and west to do the dc and baltimore areas any good as they all look like biller b typc systems. Even P002 looks like it originally had the a low up towards the eastern lakes before reforming. That usually leads to boundary layer problems. . To me, a week from now doesn't look good for the dc and BWI croud. Of course, I could always be wrong but this pattern is not last year's pattern. We still don't have a southern stream.

[ozzie]

But if you look closely the storm ones are too far north and west to do the dc and baltimore areas any good as they all look like biller b typc systems. Even P002 looks like it originally had the a low up towards the eastern lakes before reforming. That usually leads to boundary layer problems. . To me, a week from now doesn't look good for the dc and BWI croud. Of course, I could always be wrong but this pattern is not last year's pattern. We still don't have a southern stream.

So without any southern stream activity it is going to be rare to get a miller A to form which means we will have very few chances for traditional type large coastal lows originating in the South and moving northeast along the coast. It will be mostly miller B's which usually develop too late for this area to get blizzard type snowfall although there have been decent snows out of miller B scenarios. Does that sound sort of correct?

[Analog96]

So without any southern stream activity it is going to be rare to get a miller A to form which means we will have very few chances for traditional type large coastal lows originating in the South and moving northeast along the coast. It will be mostly miller B's which usually develop too late for this area to get blizzard type snowfall although there have been decent snows out of miller B scenarios. Does that sound sort of correct?

Without a strong Southern stream, it's a lot tougher South of Philly for sure.

[FrederickWX]

Cold and dry, then mild and wet... now that's the type of DC winter we had gotten used to before last winter. Sounds like it's best we enjoy any flurries we get, since we may not see anything more than that for awhile.

[usedtobe]

So without any southern stream activity it is going to be rare to get a miller A to form which means we will have very few chances for traditional type large coastal lows originating in the South and moving northeast along the coast. It will be mostly miller B's which usually develop too late for this area to get blizzard type snowfall although there have been decent snows out of miller B scenarios. Does that sound sort of correct?

Yes, unless the 204 hour GFS is correct. lol

[ozzie]

Yes, unless the 204 hour GFS is correct. lol

you are referring to the 204 hour on the 18z right?

[usedtobe]

you are referring to the 204 hour on the 18z right?

Right but it's the 204 hr and won't look the same the next run. MY guess still is the low ends up towards the lakes or sheared out.