Snow-ice-rain for the NYC forum 7PM Mon 1/25-6AM Wednesday 1/27

[donsutherland1]

1 hour ago, wdrag said:

@donsutherland1 and others  (@bluewave etal) who may look at this predictive data a lot...   has the EPS or GEFS been better at LR predictions of the AO, NAO, PNA, EPO lets say at 10 days, and 16 days?

I see some differences in the these ensembles...the GEFS overall a little more favorable for winter.  

Not sure who said winter over?   Doesn't look that way to me yet into mid Feb.

 

Maybe it is over, and I don'/didn't realize it???

Thanks,

Walt

 

 

I haven't really tried to compare the GEFS and EPS per se. However, both have had persistent difficulty beyond a week when it comes to the EPO. I'm not sure about the reason for that.

[eduggs]

This seems to have played out as modeled for the most part so far: 0.1 - 0.2 inches of liquid. A dusting to an inch of snow (slightly more near and north of 84) with a glaze on top. Rain and snow showers - mostly light - should continue intermittently through the overnight. Hopefully not too many people were fooled by the numerous inaccurate snow maps. In most cases the model is not wrong. The 3rd party algorithm to calculate snowfall is wrong.

[HVSnowLover]

1 minute ago, eduggs said:

This seems to have played out as modeled for the most part so far: 0.1 - 0.2 inches of liquid. A dusting to an inch of snow (slightly more near and north of 84) with a glaze on top. Rain and snow showers - mostly light - should continue intermittently through the overnight. Hopefully not too many people were fooled by the numerous inaccurate snow maps. In most cases the model is not wrong. The 3rd party algorithm to calculate snowfall is wrong.

I still don’t know why people post 10:1 snow maps for systems that clearly won’t produce 10:1 ratios. 

[eduggs]

Just now, HVSnowLover said:

I still don’t know why people post 10:1 snow maps for systems that clearly won’t produce 10:1 ratios. 

Well they sure are nice to look at. It's really hard to force myself to ignore them and instead consider ptype, thicknesses, ratios etc...

[wdrag]

CoCoRAHS summary posted after 930A/27 for the northeast USA.  

I thought this had a decent "initial" 19th issuance handle on the widespread wintry event (north of I78) which occurred predominantly 10A/26-5A/27 (was initially too fast by 24 hours). Models were not far enough north on primary qpf axis and heaviest snowfall (I90 widespread 4-9") since the short wave appears to me to have been stronger and further north. midway into the event daily runup.

Snow predictions on my part were wayyy too high. Essentially this was a widespread 1-3" event north of I80 to I84 where it transitioned to 2-5" event in far northern part of the NYC subforum. QPF was less than modeled along and s of I80 and and a little heavier than modeled I84 northward.  Snow ratios less than 10 to 1 s of I84 where mixed pcpn and I think 10 to 1 or a bit higher to the north of I84. 

NYC recorded it's first snowfall of the month. Yes exceeding minor but it all counts. 

So the topic worked okay but the amounts were too high due to northward translation of the short wave.  A disappointment for many but for me, I see this as another successful synoptic scale event flagged again 6+days in advance, by the modeling.  The overall modeling continues to improve. Thats the researchers/data platforms/computing power that make this happen.  

[LibertyBell]

there's a 25.0 total in there?  that has to be a major error.....

 

[wdrag]

2 hours ago, LibertyBell said:

there's a 25.0 total in there?  that has to be a major error.....

 

Regionalize. If it stands out... it's no good if a loner and a typo.  Thanks,  Walt