December Medium/Long Range Discussion

[CAPE]

20 minutes ago, Eskimo Joe said:

Honestly that's pretty impressive. If that mean output would be anywhere close to verifying then many of us would have exceeded monthly snowfall climo by mid month. Yes please! I would be very, very happy to eat crow and see snow falling.

Forecast accuracy beyond D10 is generally 50%, or the flip of a coin esp. on details like precip amounts. Likely worse for snow. Don't get too excited based on any sensible outcome it depicts outside of a week would be my advice. Personally I only use it at long leads for general longwave pattern looks, over at least a few runs.

[simbasad2]

47 minutes ago, Weather Will said:

We will find out how good the AI EPS is with winter storms in the next couple of weeks.  Lot of big hits especially NW the next 15 days.

This feels suspiciously too high. It's worth mentioning I've noticed the AIFS-ENS has a tendency to show snowfall in areas that are just really heavy rain no matter the temp. For instance, I remember Jamaica had a 1-2" snowfall mean right before Hurricane Melissa made landfall. I'd personally stick to the traditional ensembles until they can fix whatever this issue is

[Eskimo Joe]

26 minutes ago, CAPE said:

Forecast accuracy beyond D10 is generally 50%, or the flip of a coin esp. on details like precip amounts. Likely worse for snow. Don't get too excited based on any sensible outcome it depicts outside of a week would be my advice. Personally I only use it at long leads for general longwave pattern looks, over at least a few runs.

100% agreed. I do not get excited for acute threats until we're inside D3 anymore.