2010/12/05 12Z Guidance Discussion

[WhiteoutWX]

classic Miller B that history shows will become more NE centric

IOW, it will likely trend towards PHL, N & E system

Agreed this has 40N written all over it. Energy transfer from midwest clipper/low, development starts off the outer banks, mostly too late for anyone south of Philly.

[usedtobe]

Yeah- but I like the fact that the trend began on schedule. As for the models... look at the south bias from last year and see if it continues. Last night's snow looked much farther north than the GFS projection for this clipper. The Canadian did was closer and tends to handle these shortwaves better.

I'm just saying - in the east, watch that trend again. It did burn us or benefit us in Baltimore last year a few times.

Last year the blocking was different, we had a strong 50 50 low for the Dec and Feb storms and the forming actually trended north. Last night the big deal was where the vortex was to the northeast. It was just too close for the clipper to do its thing. The 168 hr storm there isn't even a good vortex up to the northeast. by 240 hours, none of the models are going to be right. Another big diffference from last year is the CPC D+11 esnemble mean last year kept spitting out major snowstorms prior to the dec and feb big snows usually 3 to 5 of the analogs were major storm periods. This year, the last two days its only spit out one minor event suggesting this year is different despite the negative NAO. Of course all my rambling above may be just plain rong as at these time ranges nothing is set in stone.

[mitchnick]

imho, the models have not been advertising the general location of the ridges and troughs this year conducive for DCA/BWI to cash in with anything of consequence

I'd feel a lot better if we could get the pesky GL low out of there and the eastern trough a bit back to the west, but its likely the placement of the GL trough that's pushing the trough further off the east coast

we're just going to have to deal with NINA climo again, like it or not

[usedtobe]

i guess i could have pulled up a map. but a ref we all know off the top of our heads would of course be simplest.

thx for your analysis, wes.

i think even with this solution not being as good as recent ones further south it's still good to see that there is *something* there. on that level at least it seems there might be some confidence growing.

I agree though I don't end to get excited except for big storms and I don't see this as being one for us but so far out in time, who really knows, not me.

[Dr No]

The Miller B near the end of the work week is key for the day 7 storm. It reloads the -NAO and assumes the 50/50 spot, keeping the storm threat from cutting into the lakes.

No matter what, and I'll forecast with 100% certainty, there will be another Arctic blast behind that storm for the week of 12/13.

[Dr No]

Last year the blocking was different, we had a strong 50 50 low for the Dec and Feb storms and the forming actually trended north. Last night the big deal was where the vortex was to the northeast. It was just too close for the clipper to do its thing. The 168 hr storm there isn't even a good vortex up to the northeast. by 240 hours, none of the models are going to be right. Another big diffference from last year is the CPC D+11 esnemble mean last year kept spitting out major snowstorms prior to the dec and feb big snows usually 3 to 5 of the analogs were major storm periods. This year, the last two days its only spit out one minor event suggesting this year is different despite the negative NAO. Of course all my rambling above may be just plain rong as at these time ranges nothing is set in stone.

To your point, the Ensemble members have every posible solution by day 6 so it's foolish to pin hopes on the Op this far out. The one positive is each member shows things getting more active later next week as the vortex winds down, whether the system type is a clipper or bonifide Miller B. And you know how the MA fares with a true Miller B, so caution is well-warranted.

Edit: the 12Z Mean gives a little more confidence to a storm threat. We'll see what each member shows later on.

[usedtobe]

To your point, the Ensemble members have every posible solution by day 6 so it's foolish to pin hopes on the Op this far out. The one positive is each member shows things getting more active later next week as the vortex winds down, whether the system type is a clipper or bonifide Miller B. And you know how the MA fares with a true Miller B, so caution is well-warranted.

Edit: the 12Z Mean gives a little more confidence to a storm threat. We'll see what each member shows later on.

Such a broad low pressure area suggests lots of variability in the solutions. The mean tends to usually be flatter than the operational. The idea of some type of system has lots of support, as you say, the details differ.

[winter_warlock]

Such a broad low pressure area suggests lots of variability in the solutions. The mean tends to usually be flatter than the operational. The idea of some type of system has lots of support, as you say, the details differ.

be intresting to see which way the euro trended for 12 z, im hoping it trended east, i dont like the inland look of the 00z run

[stormtracker]

Such a broad low pressure area suggests lots of variability in the solutions. The mean tends to usually be flatter than the operational. The idea of some type of system has lots of support, as you say, the details differ.

The panel after that looked really strong as far as signals go for ensembles.

[usedtobe]

The panel after that looked really strong as far as signals go for ensembles.

Here's the ensemble members. Note that many of them has the low too far north and west for us to get much snow unless we get a Feb 10 type miller b with the upper low going to our south. However, there is one miller a look system. I'd bet against it but have been fooled before.

[needbiggerboat]

plz try to be more specific in the future... i have (and im sure others as well) no clue where that is.

sorry...looks like others have filled in the gaps....anyway, that's at least 4 consecutive gfs runs with the ingredients for a wintry setup next sunday/monday for the dc area...while 12z not as intense or bombastic, still looks like whoever has 12-12 for the first dca inch contest is looking OK right now.

[Cyclonicjunkie]

A little off topic but would you call the 0z Euro a Coastal storm? Or maybe a Hybrid?

[Ellinwood]

sorry...looks like others have filled in the gaps....anyway, that's at least 4 consecutive gfs runs with the ingredients for a wintry setup next sunday/monday for the dc area...while 12z not as intense or bombastic, still looks like whoever has 12-12 for the first dca inch contest is looking OK right now.

Not quite...

DCA GFS MOS Guidance: 
    MON 06| TUE 07| WED 08| THU 09| FRI 10| SAT 11| SUN 12|MON CLIMO
N/X  26  39| 24  36| 23  36| 24  37| 30  46| 32  45| 32  46| 31 31 48

But I digress...

It'll be a hard time getting snow south of the MD/PA line if we can't lock any real cold air into place ahead of this system.

[Dr No]

Some of those have an Ice look to them.

But let's hope the same "SE" trend applies to the masses this time around, that happend with the clipper and what was at one point a legit mid-week threat.

[tombo82685]

hr 30-36 has some nice snow showers over the n mid atl area on the euro

[winter_warlock]

with the temps starting to moderate and no arctic air coming down right before the storm, i dont think this is going to be big maybe snow for mountains, AND NEW england, i just think it will be too warm

[tombo82685]

out to hr 78

[tombo82685]

hr 96 has the clipper coming into nd, 1004mb low

[tombo82685]

hr 108 has a 1004 low over n mn lgt precip over mn and wis

[tombo82685]

hr 120 has a 1004 low over lake superior...lgt precip over lakes with some lgt to mod precip over cent and souther mich and ohio

[tombo82685]

hr 126 has a sub 1000 low north of lake superior lgt precip over the lakes and oh valley with a little hvr burst in eastern and w pa

[tombo82685]

some lgt precip into n mid atl and northeast...coastal areas look to have isses, while interrior should be fine, but its lgt precip

[tombo82685]

hr 144 has storm enbtering the plains with gulf moisture coming north

[tombo82685]

hr 150 has a sub 1004 low over the north central ok

[Dr No]

hr 150 has a sub 1004 low over the north central ok

Ridging or flat out infront of it?

[CooL]

Hr 156 does not look too good. Cutting early

[tombo82685]

hr 168 996 low over southern indiana

[tombo82685]

hr 174 sub 992 low over western ohio

[Ellinwood]

a million updates

Hell, you're gonna be the first one to 10k posts! Is it really necessary to make a new post for every update? Least you could do is just go back and edit an old one... (my 2 cents)

[Ian]

Hell, you're gonna be the first one to 10k posts! Is it really necessary to make a new post for every update? Least you could do is just go back and edit an old one... (my 2 cents)

i agree.. we're still trying to hash out this model thread thing with regions/etc, but unless someone's reading at the time an update a minute isnt terribly useful. i'd rather see the threads in the main forum more focused on analysis... why it is what it is, why it should be taken with a grain of salt etc.