Jan 25th Winter Weather Discussion Thread

[tarheelwx]

Seems like the NAM has been more consistent the last few runs.  GFS has been a bit jerky.

TW

[packbacker]

I am discounting them, especially after last week. If the NAM is a high outlier on precip, to bet on it to pan out would the definition of foolishness.

 

I agree, but I bet the GFS is a little to dry, probably safe to go with 0.2-0.3" across the area with more NE.

[WilkesboroDude]

What event do you keep referring to?? I surely don't recall an event that was calling for a foot and got something else? I've been in Boone all winter and have kept track of every storm with the models

 

It was one of our nuisance events...I only remember this because I was the one who posted the NAM snow map. I didn't save that so I can't recall the exact date but it was the eastern parts of the mountains to about Boone with over a foot or so. 

[HKY_WX]

It's nice to see the rgem a little moist. Close to .25 for most of NC. I think if you average the mods out. probably.15 to .2 for a lot of folks. The equivalent of maybe an inch of sleet or a little less. Basically enough to put a sheet of ice on the roads.

[ncwinterwxman]

of the year statement right there

Ji: gfs can't handle this. the high res models are better

[griteater]

I am discounting them, especially after last week. If the NAM is a high outlier on precip, to bet on it to pan out would the definition of foolishness.

You basically have to cut the NAM QPF by 60% or so and warm it a bit

[mercurydime]

http://www.goes.noaa.gov/GSSLOOPS/ecwv.html

[WidreMann]

I agree, but I bet the GFS is a little to dry, probably safe to go with 0.2-0.3" across the area with more NE.

It's about the same as the Euro. And since when do models underdo precip?

[WilkesboroDude]

For me, in the short term, GFS kicked the NAM's tail last week.

 

Guess that works both ways...the western part of NC will say the short term models...including the NAM did really well. 

 

This is a totally different situation so who knows...GFS may be right. It was the polar opposite last week with way too much snow for the foothills.

[SnowGoose69]

You basically have to cut the NAM QPF by 60% or so and warm it a bit

 

LOL...in other words make the NAM the GFS

[HKY_WX]

You basically have to cut the NAM QPF by 60% or so and warm it a bit

that sounds like a tv dinner.

[beanskip]

Yeah, the problem is, we're kind of within the margin of error of a nuisance vs. a serious event. .1 of QPF (esp. with dry air to overcome) -- prob not enough to cause much trouble. .25 -- could cause a LOT of trouble.

It's nice to see the rgem a little moist. Close to .25 for most of NC. I think if you average the mods out. probably.15 to .2 for a lot of folks. The equivalent of maybe an inch of sleet or a little less. Basically enough to put a sheet of ice on the roads.

[HKY_WX]

Yeah, the problem is, we're kind of within the margin of error of a nuisance vs. a serious event. .1 of QPF (esp. with dry air to overcome) -- prob not enough to cause much trouble. .25 -- could cause a LOT of trouble.

maybe we'll get some favorable qpf  trends tomorrow. this is just not a good setup for the GOM to come into play. most clipper type systems never put out more than .25 to .3 in the way of qpf east of the mountains.

[WilkesboroDude]

NWS policy on its Winter Weather products wouldn't allow any removal of a Winter Storm Watch. They either have to replace it with a Warning if its felt like Warning criteria will be met or a Winter Weather Advisory if the numbers are lowered.

 

Really? 

 

It would make no sense for a winter weather advisory if nothing was coming (relatively speaking). I know we have had Winter Storm Watches in the past go into dud mode..but don't recall getting the benefit of the doubt with an advisory. 

[packbacker]

RGEM precip - looks like 0.3-0.4" for central NC

 

 

[SnowGoose69]

Really? 

 

It would make no sense for a winter weather advisory if nothing was coming (relatively speaking). I know we have had Winter Storm Watches in the past go into dud mode..but don't recall getting the benefit of the doubt with an advisory. 

 

I'm pretty sure they can drop them, its just more of a rarity now than it was 10 or 20 years ago because often times you're not going to get that drastic a model shift inside 36 hours to go from watch to nothing, most busts now are usually nowcast busts where you end up underperforming last minute when you'd already be under an advisory or warning.

[superjames1992]

Good news from the RGEM.

 

Granted my inner weenie is probably influencing my thinking, but aren't we getting into the range where it's best to start taking into account what the regional models have to say over the global models?  The NAM and RGEM look pretty decent.

[packbacker]

It's about the same as the Euro. And since when do models underdo precip?

 

Models???? I said I thought the 0z GFS run was a little dry for it's run and I thought the range of 0.2-0.3" is fairly reasonable for central NC based on the other models.

[Brick Tamland]

Not sure what trends people want to be favorable. It seems to have been favorable lately to me. This was never going to be a blizzard, but still looks like a pretty eventful snow and ice storm.

[WidreMann]

RGEM precip - looks like 0.3-0.4" for central NC

Two things:

1) How did RGEM do with the last event?

2) You have to ask yourself what would result in significant precip for this area. You can't just look at precip maps verbatim. Is there flow from the gulf? Is there a strong low? No. There's very little to generate precipitation except some upper level energy that will squeeze every last drop out of the atmosphere, but there aren't many drops to start with. So be skeptical of models that generate significant precip.

[Marion_NC_WX]

Really? 

 

It would make no sense for a winter weather advisory if nothing was coming (relatively speaking). I know we have had Winter Storm Watches in the past go into dud mode..but don't recall getting the benefit of the doubt with an advisory. 

 

 

It's called "covering their a$$es". The NWS is not going completely abandon a specific area just because the precip total is small. Its better and in their best interest to keep an Advisory up because a trace of precip is technically within the advisory criteria.

 

Could you imagine if a NWS office didn't downgrade to a WWA and there something impactful happened.

[WilkesboroDude]

It's about the same as the Euro. And since when do models underdo precip?

 

EURO snow maps actually look good. Accu-pro map can be seen at Henry Margusity Fan Club.

[BIG FROSTY]

GFS is giving me a nice, 0.07 qpf

[WidreMann]

EURO snow maps actually look good. Accu-pro map can be seen at Henry Margusity Fan Club.

Don't look at the damn snow maps. They are very weak heuristics. The precip totals from the Euro are not impressive and have been decreasing for several runs in a row now.

[packbacker]

Two things:

1) How did RGEM do with the last event?

2) You have to ask yourself what would result in significant precip for this area. You can't just look at precip maps verbatim. Is there flow from the gulf? Is there a strong low? No. There's very little to generate precipitation except some upper level energy that will squeeze every last drop out of the atmosphere, but there aren't many drops to start with. So be skeptical of models that generate significant precip.

 

 

Goodnight...

[Busick]

I believe it was in 2000 or 2001 where a similar system came across the mountains and winter storm warnings were up for the Piedmont,  not one flake fell from the sky! the system dried up completely after passing the mountains. I am sort of skeptical of this one, but can see a light glaze or a couple of hours of sleet for some people, unless the gulf is tapped

[deltadog03]

pray this is right?  lol

 

http://mag.ncep.noaa.gov/list_files_area.php?model=nam-hires&cycle=00&area=namer&param=sim_reflectivity

[griteater]

Good news from the RGEM.

 

Granted my inner weenie is probably influencing my thinking, but aren't we getting into the range where it's best to start taking into account what the regional models have to say over the global models?  The NAM and RGEM look pretty decent.

My opinion, but I see this as a trap that some (myself included) fall into...when we get into the range of the higher resolution, short term models (throw the NAM in that bucket), they always seem to be amped up and end up overdoing the precip. I've seen that a lot over the years. Maybe folks have seen them pan out, but I really haven't.

I don't know, would be curious as to what others think.

[SnowDeac]

Don't look at the damn snow maps. They are very weak heuristics. The precip totals from the Euro are not impressive and have been decreasing for several runs in a row now.

 

Not saying that I do (I normally pose questions for those much smarter than me when I rarely post), but do you ever post anything of value? I'm a lurker and still find you insufferable. I can't imagine how regulars put up with you.

 

Did we ever get the aircraft recon back from the GOM flights today, and do we know if it showed us anything of note?

[griteater]

I believe it was in 2000 or 2001 where a similar system came across the mountains and winter storm warnings were up for the Piedmont,  not one flake fell from the sky! the system dried up completely after passing the mountains. I am sort of skeptical of this one, but can see a light glaze or a couple of hours of sleet for some people, unless the gulf is tapped

Don't remind me, lol. Dec 2000. But I posted about this earlier today, I wouldn't put this in the typical clipper camp. It's not originating out of SW or SC Canada...and the precip is essentially driven by overrunning / warm advection in the low levels (WSW / SW flow just above the surface)...whereas, a typical clipper that drops south out of Canada is more upper level driven.