Friday, January 18, 2008

11:30 a.m. update: Bust potential high -- either way

This storm is a mess. I wouldn't want to be a NWS forecaster right now. Take Atlanta -- the 12z NAM says: 8-12 inches. The 12z GFS says: 1 inch. What do you do?

Here, the differences aren't that sever, but are marked.

The NAM held steady with a nice 2-4 inch snow for us with just under .5 of liquid. The NAM actually twitched back the west a little bit.

The GFS, however, nosed further to the east with OUR precip-- I can't get to numeric guidance yet, but we look to be at about .2 inches of liquid, which would be a dusting to 1 inch snow, maybe 2 inches tops. Yet, the area of .5-.75 precip and higher (4-5 inch snow) is in Union County, N.C. -- just 60 miles away! And the .75-1.0 inch sector (6-8 inches of snow) is only about another 75 miles ESE of that.

Meanwhile, another short range model called the MM5 gives us about .6, even more than the NAM.

Still waiting on the Canadian and UK models (which have been the farthest east).

Bottom line: I have extremely low confidence in this forecast. With a 70 mile error further east we could see a big fat nothing. With a 70-mile error further west we could see a half a foot of snow.

Then there is the differences BETWEEN the models -- the NAM gives us more than TWICE the precip as the GFS.

And we're less than 24 hours from the start of the event (still some time tomorrow morning or early afternoon).

My best guess right now is that we'll see an inch or so out of this, but that could change dramatically based on current radar observation in the Gulf or anything else for that matter.



Anonymous said...

Forcast- SNOW SNOW SNOW. Acctuality- Um well we think there may be snow but we dont know. We usually say snow is forcasted and then we dont get it so we will say NO SNOW and hopes that the trend will follow through. I say yes you say no or i say no and you say yes. Either way i am just happy there is precipitation.

Snowman said...

Getting the water is a very GOOD thing, we need it. Channel 3 is actually saying 3-6"( conservative according to them ) of snow while Channel 9 puts us in the lesser amount for precip, .25 inches. That surprises me as I hardly ever agree with Channel 9.

I still say the storm will be too far south of us for anything over an inch of snow, if that. The temps at the onset of any precip will also be a factor and I'm still not convinced it will be cold enough to sustain snow if we get it.

If it were colder toward the coast this would be a storm where Myrtle Beach could see around 10 inches of snow.

chad said...

boilings springs again and i seen where channel 3 news has the entire cleveland county under 4-6 inches.... i hope their right. 4-6 inches would be wonderful!

Anonymous said...

Chad, I just saw that too. Skip what model do they use or do you know. Thanks again for keeping up with this.

Skip Foster said...

The WBTV map is rather shocking. Even the most aggressive model -- the NAM -- falls short of showing 6 inches of snow. The best case I see is 3-5 and I wouldn't bet much more than a nickel that could happen.

I fear we will be left out in the cold, but if I had to guess right now I'd go for 1-2 inches.

Snowman said...

I was surprised with WBTV map as well. They are normally not that aggressive.

Can't miss said...

Channel 3 in my opinion is the best weather, so I think they will be right. Serveral years ago Erik Thomas said we would get a big snow and everyone else 1 inch. Well we got that big snow so I am sure of it this time. Get the sleds out!

Snowman said...

can't nmiss: WBTV now claims the Charlotte & Gastonia areas will be the one getting the most snow. I believe this to be correct as the current storm path is too far south of us to get much snow. Maybe an inch, but the storm path is critical.