Sunday, January 31, 2010

Snow Totals & More Snow This Week????

Forecast- Cville 6". Lynchburg 8". Roanoke 12". Danville 14". Greensboro 12". Salisbury 8". Charlotte 4"

Totals- *From NWS* Cville 8". Lynchburg 9.3". Roanoke 9.1" . Danville 6.5" and .75" of sleet. Greensboro 8". Salisbury 7". Charlotte 2"

So. Cville- A Lynchburg- A Roanoke- B Danville- F Greensboro- C Salisbury- A Charlotte- A

Overall: 3.00 or B

Danville killed me w/.75" of sleet. Had that been snow, I'd have been right on the money.

Overall based on my snow map things shifted more north than I forecasted and some of the highest amounts didn't verify. If I find a decent statewide total from VA I'll post it, only NC now.

4.0 Grading Scale
A: 2" +/-
B: 3"
C: 4"
D: 5"
F: 6" <

This week: chance of snow on Tuesday, mainly PM for VA. Could see 1-3" especially towards the eastern half. NC looking marginal for rain/frzra/slop. Will update tomorrow.

BIG storm on the horizon this weekend- could be a classic nor'easter. Stay tuned.

Friday, January 29, 2010

Final Snow Map

I apologize for my poor graphics skills. Also, I'm focused on the piedmont areas of NC/VA much more so than the mtns/coastal areas.

Same General Ideas

Around 6" in Cville, increasing as you go south. Sweet spot should still be around the border, especially in the mtn areas of Roanoke east to Norfolk/VA Beach.

So to grade myself, Cville 6". Lynchburg 8". Roanoke 12". Danville 14". Greensboro 12". Salisbury 8". Charlotte 4".

Hope everyone gets a good snow. Will update if need be.

Thursday, January 28, 2010

Snow Fri-Sat Update

General ideas after seeing the past few model runs:

Precip shield slowly moving north.

That matters a lot here in Cville as we are on the fringe of the heavier precip.

Too early for me to update, want to see a few more runs, BUT, looks like we could be on the higher end, if not over 6" based on 12Z Guidance.

NC is still looking good,, and Southern VA & Northern NC still look to be the best snow areas. Depending on the depth of the cold air, could be some localized 12"+

Stay Tuned.

Wednesday, January 27, 2010

Snow Fri-Sat

Update from Tues. Storm is still coming, but taking a more southerly track. Looks like the best snow will now set up south of us, around the NC/VA border. Current thinking is we're looking for around 4-6" in Cville, rising to around 6-8" near Danville south to SALISBURY, NC and points east. Below that around 2-4", then wintry mix in upper SC.

See my very poorly drawn map for more info.

Monday, January 25, 2010

Measuring Snow in FEET Again???

OK. I'm hyping this one even though it is 4 days out, mainly because I missed the last big snow here back in December, and I want to see another bomb. Definitely going out on a limb following forecast models that are still 4 days out. For those who don't know much about weather forecast models, 4 days away is a long time and leaves a lot of room for error. That's why everybody always blames the weather-guy for a bad forecast- he's looking at model data to make it, and if it is wrong, usually the meteorologist is wrong. Basically, that's just my CYA statement in case I'm wrong. But it is important to understand that the system that will affect us in Charlottesville on Friday is just coming into the West Coast, and better data is obtained once a system is on land, therefore the closer we get, the more accurate the models become because they have more accurate surface and upper-air observations fed into their initializations which future-cast the weather.

With all that said, at this point I would say 75% chance of 6" of snow between Friday and Saturday. 50% chance of 1 foot. 25% we see 18". But percentages aside, right now I think we'll see approximately 1 foot of snow here in Cville. Lots of factors will affect accumulations, the important ones are how cold is it at the surface and where snow crystals form. It is probable that towards the heaviest part of the snow we'll start seeing ratios as high as 15:1. That means for every tenth of an inch of precip (.10) 1 1/2" of snow would fall. Typically it's around 10:1, so .10 = 1". The picture I posted is the latest operational run (18Z) of the GFS model which shows 1.25"-1.75" of liquid around our area. Doing the math using 1.5" of liquid means 15" of snow at 10:1 ratios and averaging to 13:1 for beginning to end equals 19.5" of snow with the same 1.5" of liquid. Again, this is subject to change, but not to the point of looking at green grass all weekend. We just might not be in this sweet spot. I expect to see 1" of liquid (QPF) generally, which is why I'm forecasting 1 foot. I'll update as we get closer. Stay tuned.

Friday, January 22, 2010

Forecast BUST- More Cold to Come Next Week

OK. Even though it was a few days out, my forecast was crap. We had the kind of weather that drives me nuts in the winter: A cold 33 degree rain. We saw a little sleet, but other than that nothing. A few report of up to 2" of snow/sleet up in the higher elevations, where they had icing as well. I still do not understand the local NWS Office posting and then holding us under a Winter Storm Warning for so long when it was clearly not going to verify. A simple look at the wet bulb temps yesterday afternoon and night told the story: not going to freeze.
Any-who, after a warmer soaking rain on Sunday and maybe again Thur/Friday (Sun might even have some Thunderstorms with it), the northern jet/polar air get back into the mix by next weekend and then we can start looking to see if the southern stream (moisture) hooks up with it. Right now the GFS has -20 isotherm at 850mb into VA next Saturday. Raw printout numbers for low temps with that are around 10. It's a ways off, but a telling sign of the recent thaw coming to an end. Pray for snow.

Monday, January 18, 2010

Goodbye Warmth- Winter Storm Thursday

So check it. Complex winter storm developing for Late Wed/Thursday here in Cville. High bust potential because there isn't a lot of cold air around...BUT it still looks like marginal temperatures plus plenty of precip is going to lead to white stuff on the ground. As of right now, it looks to be a messy storm: rain, freezing rain, sleet, and snow. Which combination and for how long will determine accumulations. The farther north and west you go from Charlottesville, the better chance for a snow/sleet mix. When I say marginal, I mean the difference in half a degree from ~5,000 ft (850mb) to the surface will determine the type of precipitation.

Best guess for Charlottesville right now: Rain late Wednesday turning to Sleet and Snow overnight. Total snow/sleet accumulation: 4". Again, high bust potential either way with 1" of liquid being the average model output. Stay tuned.

Thursday, January 14, 2010

So I Missed the BIG ONE

A little late updating on the Dec 18th-19th storm here in Charlottesville. I drove through part of it, but by the time it was winding down I was somewhere between Chicago and China. Officially 21" fell here, but amounts were variable with 28" reported in Harrisonburg, 20 miles west. So I missed the biggest storm here in the past 15 years, which would piss me off if I hadn't been bound for an awesome Thailand vacation. So, just to recap, I've linked the header to the analysis of the storm which has been ranked a category 3, or major snowstorm by NOAA on the NESIS scale. That stands for Northeast Snowstorm Impact Scale...Anyways, check out the link, it also references other big storms over the past few decades.

As for now, the January thaw is in full effect here...stay tuned for more updates.