February 2019 Forecast Discussion and Observations

[earthlight 25,424]

On the bright side it would be a beautiful, sunny day in the warm sector!

[Allsnow 41,941]

Just now, earthlight said:

On the bright side it would be a beautiful, sunny day in the warm sector!

Some of the eps members looked like this. Very possible with southeast ridge and strength of low 

[earthlight 25,424]

Not a bad severe wx setup around here, gotta get temps up past the 70’s near the warm front

 

 

[earthlight 25,424]

1 minute ago, Allsnow said:

Some of the eps members looked like this. Very possible with southeast ridge and strength of low 

 

Has a lot more to do with the evolution in the Pac and Canada - they completely control the SE ridge

[Nchaboy 2,692]

1 minute ago, Allsnow said:

Some of the eps members looked like this. Very possible with southeast ridge and strength of low 

You did say this yesterday not to get our hopes up. Very volatile pattern. 

[Event Horizon 1,546]

ECMWF Today.

 

 

Yesterday. 

 

[RAllen964 1,986]

Primary control in the Great Lakes.

 

this was over before it started 

[Allsnow 41,941]

Sunday night into Monday could be a better opportunity for snow then Tuesday night 

[MatthewFerreirawx 736]

FV3 and CMC still a snow event while GFS and ICON have a primary GL low. It'll be fun to see what 12Z EURO and EPS do.

[33andrain 65,023]

[Nchaboy 2,692]

This might be a dumb question but what caused the 50/50 not to be in the right spot in this run? 

[Oglem 1,141]

Hey everyone, I'm going to try to analyze this. Please correct me if I'm wrong, but here goes:

From what I can tell, these are the 3 crucial differences on the 12z GFS vs 00z and 06z:

 

1. EPO ridge doesn't reach as far into Alaska. It is a bit flatter. It's also more North-South oriented. We want it oriented a bit more West-East to tilt the Western trough positive, which allows our shortwave to maintain positive tilt for longer

 

2. There was less blocking over top in 12z in Northern Canada.  

 

3.  Our 50/50 Low has moved significantly East compared to 06z, and this means that the high in SE Canada that should be supplying us with cold is now shifted to the East, opening the way for the storm to cut to our West vs 06z. 

 

[Oglem 1,141]

15 minutes ago, Nchaboy said:

This might be a dumb question but what caused the 50/50 not to be in the right spot in this run? 

I might be wrong, but to my eyes it seems that the 50/50 was in the right spot for much of the run, but because there was less blocking over Greenland, the low just moved before the storm arrived. There's definitely a great 50/50 feature early in the 12z run. It looks like there's a second low pressure that moves in behind the initial low to reinforce 50/50 after the first one begins moving out. The reason that it moves in behind the first low as a separate system is because blocking separates them. It's this second low that keeps the 50/50 low pressure going for so long in the 06z run. In the 12z run, both lows consolidate early because of lack of blocking and move out early, also, because of lack of blocking. I hope this is correct. 

[earthlight 25,424]

6 minutes ago, Oglem said:

Hey everyone, I'm going to try to analyze this. Please correct me if I'm wrong, but here goes:

From what I can tell, these are the 3 crucial differences on the 12z GFS vs 00z and 06z:

 

1. EPO ridge doesn't reach as far into Alaska. It is a bit flatter. It's also more North-South oriented. We want it oriented a bit more West-East to tilt the Western trough positive, which allows our shortwave to maintain positive tilt for longer

 

2. There was less blocking over top in 12z in Northern Canada.  

 

3.  Our 50/50 Low has moved significantly East compared to 06z, and this means that the high in SE Canada that should be supplying us with cold is now shifted to the East, opening the way for the storm to cut to our West vs 06z. 

 

 

Excellent analysis - all of these changes led to a different evolution. 

[ThunderSnow4 81]

Awesome analysis so far on here today! Sheesh the FV3 appears to me a big hit! Wasn’t it supposed to overtake the GFS a while ago? If not can someone fill me in on when that take over will commence? It has performed very poorly in our neck of the woods. 

[Nchaboy 2,692]

11 minutes ago, Oglem said:

I might be wrong, but to my eyes it seems that the 50/50 was in the right spot for much of the run, but because there was less blocking over Greenland, the low just moved before the storm arrived. There's definitely a great 50/50 feature early in the 12z run. It looks like there's a second low pressure that moves in behind the initial low to reinforce 50/50 after the first one begins moving out. The reason that it moves in behind the first low as a separate system is because blocking separates them. It's this second low that keeps the 50/50 low pressure going for so long in the 06z run. In the 12z run, both lows consolidate early because of lack of blocking and move out early, also, because of lack of blocking. I hope this is correct. 

Great job btw !! And yea that’s what it looks like. 

[Mriceyman 2,100]

14 minutes ago, ThunderSnow4 said:

 Wasn’t it supposed to overtake the GFS a while ago? If not can someone fill me in on when that take over will commence? It has performed very poorly in our neck of the woods. 

Hopefully never?

[RAllen964 1,986]

Looking at 250, look at that jet screaming into California. 190 knots! 

 

 

[Brian5671 1,023]

9 minutes ago, RAllen964 said:

Looking at 250, look at that jet screaming into California. 190 knots! 

 

 

Story of the winter-it's really killed the ridge that we need out there...

[Oglem 1,141]

35 minutes ago, Nchaboy said:

Great job btw !! And yea that’s what it looks like. 

Thanks! I owe most of my weather knowledge to reading the posts of the mets and seasoned amateurs on this site. This is far and away the best weather&meteorology site out there. There's just so much high quality information here.