Jump to content

17th-19th Post Pres Day threat


Recommended Posts

I would pick the model that shows the most pressure gradient as the lows are riding the line big time. Last night I said the LP was diving further south and it did. In 1994, the same thing was happening when we had extreme cold temps and snow cover. Mid- range models in 1994 were crap and only the 48 hours models helped. The Qpf are all wrong for this next storm and the GOM will play a big part. Instead of watching just the models, with this extreme cold and progressive pattern, watch the WV maps. They say it all.

http://msiegelweatherman.blogspot.com/

1994 was 20 years ago, haven't model enhancements since then improved performance relative to such biases? (Not meant critically, just trying to learn and understand...)

Sent from my iPad using Tapatalk HD

Link to post
Share on other sites
  • Replies 538
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Popular Posts

Good call dude.

Wanted to show how ridge position is playing a big role here. first image is 0z last night, second image 0z yesterday. Notice the the difference in the location of the ridges. 0z further offshore and

Still a solid hit south of the PA Turnpike. Heisenberg can stop worrying for a little while longer.   It's a faster in, faster out with a little less QPF. It's a good snow for Philly.

1994 was 20 years ago, haven't model enhancements since then improved performance relative to such biases? (Not meant critically, just trying to learn and understand...)

Sent from my iPad using Tapatalk HD

IMHO Nope. A good example is when the ground has a deep snow pack and we have great decoupling. Cold temps bust almost  every time. The models have been significantly better with airflow and moisture patterns but have been lacking on one thing- incorporating historical meterology patterns and additional sampling data. We have had only 20-30 years of decent weather computer models to rely on and the lack of sampling over the Pacific Ocean has still been a detriment for trusting weather models further out than 48 hours. Maybe in a few years this problem can be overcome but as long as we have a deep pool of cold air over the U.S with a deep snowpack, relying just on airflow data is not enough. We have only half the picture(data) when models come out when we need to have the whole picture when relying on accurate computer modeling to make more accurate forecasts. Back in 94, we did not have have the luxury of model runs every 6 hours available to the public on the internet let alone the other differnett ype of weather models available today. We relied on morning and late afternon runs and that was it and we did not go stir crazy until we were at least 48 hours from the storm event because we knew things could change. We have gotten away from this theology and we need to return to this. The NY blizzard faux pas was a great example of this

  • Like 2
Link to post
Share on other sites

21z sref

Nice to see some decent model consistency 48 hours out. Nice change from the rather large spread we've hAd with other storms in the eastern us

next frame might show more. On vista, 21z srefs on there show .5 to about edison-nxx-lom-mqs line

Link to post
Share on other sites

The QPF totals have steadily increased through the day as well. KPHL 09Z SREF QPF mean was 0.42", 15Z was 0.51", Mean plumes for new 21Z run is 0.56". 

the only thing with srefs though and I just looked is it looks like the arw suite is skewing the mean. The whole arw package is like .8-1" qpf, nmm ones are mainly under .5 and nmb are scattered throughout. Seems like in every event the arw's are always to wet.

  • Like 1
Link to post
Share on other sites

Anyways, NAM looks like its going to have a little more baja low interaction which should cause for a stronger low. Looks like a little more northern stream digging here as well, which should help raise hgts along the coast a little.

Link to post
Share on other sites

Anyways, NAM looks like its going to have a little more baja low interaction which should cause for a stronger low. Looks like a little more northern stream digging here as well, which should help raise hgts along the coast a little.

I was hoping the trailing vort would become the more dominant one because I thought it had more room to amplify than this first wave did, but I think we are getting all we can out of this first wave. Looks my starting this thread may not have been a kiss of death.

Link to post
Share on other sites

I was hoping the trailing vort would become the more dominant one because I thought it had more room to amplify than this first wave did, but I think we are getting all we can out of this first wave. Looks my starting this thread may not have been a kiss of death.

Yea, like i said when you made the thread, I liked the setup better than the inv trof thing we had yesterday.

Link to post
Share on other sites

Nam is coming in more north with precip, stronger low to. 

The NAM is noticeably wetter in VA than it's 12Z run.

post-829-0-97362000-1424052916.png

 

Whether it be due to more influence from the Baja low (starting to see interaction with s/w on wv) or the depth of the s/w trough, note the steady stream of moisture over Mexico heading into the southeast. Could be due to better influence of sub-tropical moisture. The image is WV overlayed with RAP derived 500mb heights and winds.

post-829-0-94567500-1424052976.png

  • Like 2
Link to post
Share on other sites

The NAM is noticeably wetter in VA than it's 12Z run.

attachicon.gifWet VA.png

 

Whether it be due to more influence from the Baja low (starting to see interaction with s/w on wv) or the depth of the s/w trough, note the steady stream of moisture over Mexico heading into the southeast. Could be due to better influence of sub-tropical moisture. The image is WV overlayed with RAP derived 500mb heights and winds.

attachicon.gifWV Texas.png

Yea you can see  on this run, there was more baja energy influence which probably beefed it up and strengthened it. Also looked like the northern stream s/w was a bit stronger this run, dug a good bit more.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    No registered users viewing this page.


×
×
  • Create New...