The Jan 9-10 Storm Part 2

[Wow]

exactly, and i just found out why the GFS diminishes our precip by its arrival here. Its 5H is great, and like others.;But its 850 low which was normal up until about 66 hours, suddenly gets lost and left back in southern Mississipp, while the surface low is over Jacksonville. It loses its lift here, yet makes no sense but thats why I think it failed to keep lift for western SC and NC. Its been doing this several runs. The comma head moisture is a typical great look, just nothing much coming out of it, or as much as you'd expect.The weakening of the of the s/w may be upsetting its stomach, so it may be weakening it too quickly and unevenly among the different layers of the atmosphere. Or maybe we'll learn a lesson out of all of this in the end if the GFS and the rest of the models end up being accurate with the output.

You can see the minor differences in the the 6z and 12z NAM at 500mb yet shift the precip line 100 miles south.

[flurry]

Latest HWO for BMX has a "4" for winter weather for Sunday and Monday...Also has a "1" for Tuesday...Getting more confident

http://www.srh.noaa.gov/bmx/?n=hwo

[HKY_WX]

I would always use caution w/ the models on event like this until the s/w is onshore California. It's also probably going to be important to wait until after the clipper comes through and the models sample the degree and depth of the trough behind it. Most of this won't be played out until probably 12z to 18z tomorrow. IMO this will be another 9th inning event as far as the models go. The main reason is below. Notice how far the great lakes 500mb cutoff moves in 48 hours. Do you really think the models are going to pin down that timing until the last day or so? I don't. That's important b/c the quicker that exits, the less our southern vort shears out.

[rockchalk83]

I am very interested in the discussion going on here with the models. I have a question for the mets on here that may or may not be OT though, how have the models been doing with regards to forecasting precipitation in winter storms this year? I ask that not only for the upcoming event in the southeast, but for our own winter storm back here in the central plains (KS, OK, NE, MO).

[Amos83]

I am very interested in the discussion going on here with the models. I have a question for the mets on here that may or may not be OT though, how have the models been doing with regards to forecasting precipitation in winter storms this year? I ask that not only for the upcoming event in the southeast, but for our own winter storm back here in the central plains (KS, OK, NE, MO).

Actual QPF has been higher that models have forecast generally. That even goes for the two storms I saw in Illinois over the holidays. both the NAM and GFS were a goot bit too low on actual precip.

[Shawn]

Something to keep in mind when trying to decide when the warm nose arrives. Each plot is the 850mb temp at the given time stamp while the precip is for the previous 6 hours. To get a good idea of how much falls as snow, look at the prior map and the location of the 0c line. On the gfs for example, at hour 72, it runs from roughly rome to augusta..of course precip is still falling at this time. But at hour 78 it has moved to the north. This implies that at least part of the 6 hour precip that falls between 78 and 84 is snow. But it's easy to mistakenly look at the 78 hour map and think all of it is something other than snow.

By hour 78, (even though most of the heaviest precip has moved out of these areas), the 850mb temps of only 1 or 2c run along a gainesville to north of augusta to south of columbia line. But if you combine that with 950mb to surface temps in the mid to upper 20s implies that whatever is falling by this time is probably light sleet. north of augusta to columbia and freezing drizzle/freezing light rain south of there.

By hour 84, whatever is left falling should be freezing rain/drizzle though as the boundary layer warms a little and the warm nose expands.

Interesting to see the gfs hang back more light freezing rain after the main event this run.

Yes, I totally understand. The CAE area should get snow to begin with no doubt and I definitely understand these numbers are measured after 6 hour intervals. So it could be the last 2 min of that 6 hr interval the precip changes from snow to sleet. On the new GFS, .39 falls by 18z Monday with temps raising to 1.3 @ 850. When that temp change occurs is beyond me, but by 00z .27 more falls with 850's at 3.0.. so I'm assuming around that area is when the snow goes to sleet and then ultimately freezing rain for about .44 more qpf total. As long as we get a couple good inches of snow, the ice shouldn't be as big of a impact.. as power companies/equipment will be able to drive on the ice covered snow vs. ice covered road.

[Cheeznado]

I can never sleep long when there is a storm brewing

Well, the storm here is still on track, models hardly budged for GA- still looks like a 6" or more (go NAM!) thump of snow wit some sleet and ice before ending. I will take that in a heartbeat. I wonder if FFC will still have 1-2" LOL.

[AirNelson39]

<br />I would always use caution w/ the models on event like this until the s/w is onshore California. It's also probably going to be important to wait until after the clipper comes through and the models sample the degree and depth of the trough behind it. Most of this won't be played out until probably 12z to 18z tomorrow. IMO this will be another 9th inning event as far as the models go. The main reason is below. Notice how far the great lakes 500mb cutoff moves in 48 hours. Do you really think the models are going to pin down that timing until the last day or so? I don't. That's important b/c the quicker that exits, the less our southern vort shears out.;

Exactly, do people not remember the drastic changes the models had once the s/w was on land for the Christmas storm???? Geez people it WILL get stronger with more qpf in central and WNC, mark my words and stop nearing the cliff!

[SnowNiner]

<br /><br /><br />

Exactly, do people not remember the drastic changes the models had once the s/w was on land for the Christmas storm???? Geez people it WILL get stronger with more qpf in WNC, mark my words and stop nearing the cliff!

Yeah, I agree with the "wait till the storm in on land" crowd. Made a big difference for the Christmas storm. However tomorrow if the trend is weaker and no QPF around 12Z, I'll have to take a dive. I just can't remember a gulf low storm that we get LESS snow than Atlanta. Usually we get 40% more it seems. For the moisture to just die in SC seems off, knowing nothing about the technical aspects, only past storm history and climatology.

[WeatherNC]

Foothills or any Mod: Could you kindly educate an ol lurker and give some examples of the miles off the coast, close to coast, ect that would effect the carolinas especially with this strom? I have read about the positions of Miller A/B storms but if it could be put in laymen terms, much appreciated... If I posted this in the wrong area please advise and move appropriately. Thanks in advance

I am very interested in the discussion going on here with the models. I have a question for the mets on here that may or may not be OT though, how have the models been doing with regards to forecasting precipitation in winter storms this year? I ask that not only for the upcoming event in the southeast, but for our own winter storm back here in the central plains (KS, OK, NE, MO).

Please stop targeting your specific questions to the mets, I know you would rather have them answer it, but just ask the question to the community as a whole and see what response you get. That is proper etiquette and there are many members who could answer it just as well.

@Eastnc: In a typical Miller A, GOM to FL panhandle track, you would want the low about 150 miles off Cape Lookout, maybe just a little further given your proximity to the coast. This is highly variable though as strength of the low, as well as cold air supply can give varying results in terms of precip types. This setup smells like a hybrid type deal to me, with the mixed bag, given how the 850 low tracks well to our west, before transferring to the coast off the VA Capes. Best guess for Havelock and New Bern atm, would be -SN to start, before quickly transition to a very cold RN. QPF amounts and thermal profiles are still in question, so this could change.

@rockchalk: Guidance within about 72hrs of the Christmas storm was pretty spot on in terms of QPF for the Coastal Plain of the Carolinas. QPF trends in your area, and TX, either under or over forecasted, should translate east. Determining whether or not you will get more or less precip than what a general consensus shows at this stage is impossible.

[MotoWeatherman]

The effects of the storm will be long lasting as the only day above freezing in N GA looks to be a brief period on Tuesday otherwise highs are progged to be below freezing Mon, Wed - Fri per the GFS.

[Cheeznado]

The effects of the storm will be long lasting as the only day above freezing in N GA looks to be a brief period on Tuesday otherwise highs are progged to be below freezing Mon, Wed - Fri per the GFS.

Yes, schools may be closed for a week or more in some places.

[rosie]

Yes, schools may be closed for a week or more in some places.

Schools were closed here for 4 days after the 12/12 snow and that was 4 inches.

[Wow]

Canadian looks similar to GFS wrt precip amts. It still wants to charge the western energy in quite a bit.

[beanskip]

Weaker with the surface low than the 0z run, which is a trend now with all the models.

Also, basically just stalls out the surface low at 72 hours -- at 84 hours it has weakened, but is essentially in the same place on the Gulf Coast.

We need to see some trending with the initial wave looking stronger, not weaker.

Canadian looks similar to GFS wrt precip amts. It still wants to charge the western energy in quite a bit.

[HKY_WX]

Canadian looks similar to GFS wrt precip amts. It still wants to charge the western energy in quite a bit.

Still .3 to .4 over most of NC. And this is probably the worst case scenario as far as qpf. These southern lows never dampen out as much as the ggem/gfs always show. They are probably the worst models to use iin this scenario. Ukmet/euro are better models with southern stream systems.

[Gastonwxman]

Canadian looks similar to GFS

So does the UKMET to an extent with both of them having the same pressure reading and nearly the same location of the low, but this is only at the end though at 72 hr. so I can't say for sure. Not really much of an in-depth kind of guy with this model.

[Wow]

Weaker with the surface low than the 0z run, which is a trend now with all the models.

Also, basically just stalls out the surface low at 72 hours -- at 84 hours it has weakened, but is essentially in the same place on the Gulf Coast.

We need to see some trending with the initial wave looking stronger, not weaker.

I think the only card left to play is the "500 low isn't onshore yet" card. This needs to hold together longer either with a stronger s/w or a faster ejecting PV.

[MichaelJ]

I know it is in fantasy land but anybody see the 06z DGEX? MAJOR eye candy!

[Wow]

Still .3 to .4 over most of NC. And this is probably the worst case scenario as far as qpf. These southern lows never dampen out as much as the ggem/gfs always show. They are probably the worst models to use iin this scenario. Ukmet/euro are better models with southern stream systems.

And the 0z Euro was even weaker with the surface reflection and precip amts than the GFS. Hope for the best with the 12z Euro?

I'm not saying we're out of the game. Certainly not, but there's some really good agreement with all of the major models on the precip amounts right now. It irks me a bit!

[SN_Lover]

NAM is looking good precipitation wise.

[Snow haven]

NAM is looking good precipitation wise.

thats only 3/4-1 inch this map is in inches right?

[HKY_WX]

And the 0z Euro was even weaker with the surface reflection and precip amts than the GFS. Hope for the best with the 12z Euro?

Generally the euro chart's its own course. So we'll see. I'm not going to get too worked up over any one solution for another 24-36 hours. It's still friday morning and we're talking about a Monday system in NC.

[Wild Weather Monger]

The effects of the storm will be long lasting as the only day above freezing in N GA looks to be a brief period on Tuesday otherwise highs are progged to be below freezing Mon, Wed - Fri per the GFS.

The cloud deck also is progged to hold firm through Tuesday. Road crews, such as they are, will have their hands full. Even ole sol looks to be of little help.

And one other thing that hasn't been touched on. During the height of the storm, winds will be blowing at 20 mph with higher gust. Pinch me. Dare I say drifting snow in these parts!

[strongwxnc]

To point, and I keep coming back to this. I had .41" from the Christmas storm with 5" solid on the ground.

I still assume these go around that the ratio will be higher than what we saw (or this area) during the last storm....

Still .3 to .4 over most of NC. And this is probably the worst case scenario as far as qpf. These southern lows never dampen out as much as the ggem/gfs always show. They are probably the worst models to use iin this scenario. Ukmet/euro are better models with southern stream systems.

[Wow]

I know it is in fantasy land but anybody see the 06z DGEX? MAJOR eye candy!

Between 0.5-0.75" QPF over most of NC. Better for N NC, but it's actually not that far from the general consensus. Better than most though.

EDIT: Probably more than that.. just saw the 6 hr frames. Nice band over W NC there at 84. Don't think the cumulative maps account for it. Shame it's the DGEX!

[strongwxnc]

Yes Shame.. But the DGEX has been constant over the last few days. Well, some what. However, I agree with you, it is close to the general line right now. Just beefed up some.

Trying to get your foot John.

Between 0.5-0.75" QPF over most of NC. Better for N NC, but it's actually not that far from the general consensus. Better than most though.

EDIT: Probably more than that.. just saw the 6 hr frames. Nice band over W NC there at 84. Don't think the cumulative maps account for it. Shame it's the DGEX!

[KChuck]

thats only 3/4-1 inch this map is in inches right?

Total Precipitation (in) at bottom of image would seem to indicate inches, would it not???

[Wow]

Another issue is at the 850mb level. There's a general consensus among the models that it'll be warming up as the event wears on. There's a good chance there will be mixing as far west as the foothills in NC.

[burgertime]

Between 0.5-0.75" QPF over most of NC. Better for N NC, but it's actually not that far from the general consensus. Better than most though.

EDIT: Probably more than that.. just saw the 6 hr frames. Nice band over W NC there at 84. Don't think the cumulative maps account for it. Shame it's the DGEX!

Well the DGEX has been consistent at least and with it seeming like we are in the jackpot might as well believe it .....by the way I'm with Brandon on this, I know I'm not the sharpest tool in the shed or anything but I don't see why people are getting worked up over a days worth of "trends". If tomorrow it keeps going down then I'll be on the cliff but like I said earlier I'm willing to make a large wager that the northern shield gets much healthier by 12z or 00z tomorrow.