GEFS has made very good progress, look how much it’s sped up, also northern stream slowing down and looks a little bit better positioned
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Pattern Nippy November
- Thread starter jackendrickwx
- Start date
GEFS has made very good progress, look how much it’s sped up, also northern stream slowing down and looks a little bit better positioned
EPS has fewer snow solutions but looks better at H5.
00z
12z
00z
12z
Bryce Shelton
Member
Maybe he was asking for some opinions? No need to be rude about it.
Webberweather53
Meteorologist
There's still some takers on the 12z EPS. Arkansas & Tennessee have more model support & are more climatologically favored to pick up snow/ice at this of the year.
Webberweather53
Meteorologist
Definitely one of most impressive looking EPS suites at least for KGSO. Roughly 10-15% of members are showing a storm at day 7-8.
The moment you realize you have the same statistical probability to receive an inch of snow as Columbia SC..
Webberweather53
Meteorologist
To reiterate, this is actually the classic pattern you often see immediately preceding overrunning &/or anafrontal-type winter storms in the southern US w/ a big cold trough over the Lakes and southern stream shortwave over the southwestern US. If only it wasn't November and over a week away.
Details will make all the difference between cold & dry, a nice light-moderate impact early season winter storm or cold rain w/ a storm cutting up to the Lakes & OH valley. All 3 of these general scenarios are legitimately on the table but one of them is very likely to transpire.
Details will make all the difference between cold & dry, a nice light-moderate impact early season winter storm or cold rain w/ a storm cutting up to the Lakes & OH valley. All 3 of these general scenarios are legitimately on the table but one of them is very likely to transpire.
pcbjr
Member
Regardless of the end game ...
Webberweather53
Meteorologist
The 12z EPS looks brutally cold next Wed & Thu for this time of the year. The EPS mean for Wed Nov 12 would already tie a record low max at KCLT (43F (1894)), & I could see this number ticking down another few degrees as we get closer to verification.
How about Columbia SC?
12k NAM has a downright cold day for most this Friday
Webberweather53
Meteorologist
^ not to mention on the nam quiet snow showery if anyone wants to drive up the NC mountains Friday morning. Moisture fades but should be enough esp western slopes
EPS is amazing at H5 and looks to be reloading at 240hrs. November to Remember may happen.
Apparently the GFS stalled out at hr 72 on model sites, however off of the NWS source, NC gets flurries
pcbjr
Member
I hope this doesn't violate posting rules ... but with all the discussion about a cold November leading to a hot December, or not ... it's all models and history, which does not necessarily repeat itself (do not repeat themselves to be grammatical) ... but thinking about what's not supposed to happen, after 9 years of marriage and no kids and being told it was "impossible", suddenly 2 of the best boys you can imagine came down the shoot ... so there's always a chance for a blessing, and when they happen, they can come in twos ...
decipher this and you're not at happy hour ...
decipher this and you're not at happy hour ...
Good evening everybody, I hope all is well.
With our small chance of snow next week, I went ahead and analyzed all the data and created a graphic (see below)
*Disclaimer This data is based on model analytics and is no way includes model biases or any human forecasting*
Data: 12z EPS and GFS ensemble members, reflected from Weatherbell Meteograms
Region: KGSO (Greensboro) Most Triad regions apply, even triangle regions wouldn't be too far off
Section 1. Mean
What I did with this set was as I created my excel spreadsheet, I set up the members and found their averages separately. The second thing I did was, weigh the members seperately. The GEFS was weighed 40% of the total; 1.1(mean) was multiplied by .40 and I got .44 The EPS was weighed 60%, I multiplied .29(mean) times .60 and got 0.171. I then added the total and got my average in which see below which is 61". Nothing Incredible
Section 2. % of members show snow
A bit more self-explanatory, I turned the members that showed snow into a percentage.
Section 3. Consistency.
What is did here was to use the mathematical formula, Mean Absolute Deviation, or for short MAD. Essentially It's the average distance the ensemble members are away from the mean. The process would be finding the original average, subtract the average from each member and find the average of that product. It is helpful because it lets you know whether a model is much more or less likely to verify. So essentially the smaller the number, the more likely that model set will verify and vise virsa, you could have a mean with 100 inches of snow, but will a low number, that would most likely verify, a high number and that means that 100 mean probably has a couple 50" members and a few 200" members.
Summary: This snow chance at the moment is very low right now, however, bears watching. As we head into the week, I hope to keep track of all these variables.
With our small chance of snow next week, I went ahead and analyzed all the data and created a graphic (see below)
*Disclaimer This data is based on model analytics and is no way includes model biases or any human forecasting*
Data: 12z EPS and GFS ensemble members, reflected from Weatherbell Meteograms
Region: KGSO (Greensboro) Most Triad regions apply, even triangle regions wouldn't be too far off
Section 1. Mean
What I did with this set was as I created my excel spreadsheet, I set up the members and found their averages separately. The second thing I did was, weigh the members seperately. The GEFS was weighed 40% of the total; 1.1(mean) was multiplied by .40 and I got .44 The EPS was weighed 60%, I multiplied .29(mean) times .60 and got 0.171. I then added the total and got my average in which see below which is 61". Nothing Incredible
Section 2. % of members show snow
A bit more self-explanatory, I turned the members that showed snow into a percentage.
Section 3. Consistency.
What is did here was to use the mathematical formula, Mean Absolute Deviation, or for short MAD. Essentially It's the average distance the ensemble members are away from the mean. The process would be finding the original average, subtract the average from each member and find the average of that product. It is helpful because it lets you know whether a model is much more or less likely to verify. So essentially the smaller the number, the more likely that model set will verify and vise virsa, you could have a mean with 100 inches of snow, but will a low number, that would most likely verify, a high number and that means that 100 mean probably has a couple 50" members and a few 200" members.
Summary: This snow chance at the moment is very low right now, however, bears watching. As we head into the week, I hope to keep track of all these variables.
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Am I wrong for wanting to see that Low east of VA/NC clear out sooner?Past 6 GFS runs, looking good actually. North trend for the tail end surface low.
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