usedtobe

Here's a question for you.  Why does the NAM have a separate max over our area.  It's not related to a jet streak.   The low is well to the south as is the precip associated with the low.  The vort is a meager looking thing arguing for a flat look.  An inquiring mind would like to know. 

If you want icing, hope the precip stays on the light side, otherwise the freezing on contact will reolease too much latent heat to get you the icing you crave,

23 minutes ago, WxUSAF said:

Glad I’m in good company @usedtobe! I’d still lean toward the euro on total precip and the NAM more for temps and thermal profile.

Thanks but I like the CWG forecast of 2 to 5 for the city and 3 to 7 or 4 to 7 father out towards the northwest.  I don't trust the GFS amounts so lik eyou I'd lean towards the Euro amounts and the NAM timing of the changeover.  The bottom axis of really heavy precip will determine our fate. 

25 minutes ago, WxUSAF said:

A euro/3k NAM blend is usually a good forecast in a CAD situation like this. That’s where I’d lean.

Me too!  I also like the idea of the heavier precip focusing a little to our north because as the low lifts to north west of the mountains temps will warm across Kentucky and western WV setting up a frontal boundary to focus the precipitation.  That's what the NAM and Euro seem to be doing.  Heck no one likes to look at the SREF.  It has a mean of 3 inches over DC because it has members that fringe us to the north but also have a four 5 inch plus members to balance it out.  its mean is pretty much in the Euro, NAM camp.  The other caveat is for the snow changeover go with the fastest model but at the surface relay on the slowest one to warm the temps. 

47 minutes ago, stormtracker said:

lol, NAM has frozen for about 80% of the storm.  Nasty freezing rain sometime between 18z and 22.  But that's a unicorn.  It's not going to be that bad with heavy rain and temps at 31-33 degrees.

Yep, 31 or 32 doesn't work with heavy rain since the freezing process releases latent heat.  The snow maps from the NAM are crazy and not very realistic with this type of pattern.  Think it must include sleet in its forecast amounts. 

7 minutes ago, PDIII said:

I see @usedtobe lurking. Havent seen him post hardly anything this year

 

I think I did prior to our one snowstorm.  I'm not excited by this messed up system.  Where I live,  looks like a mostly rain event maybe starting as sleet Sunday night. 

7 minutes ago, PrinceFrederickWx said:

Calvert county schools did the smart thing keeping students in for the rest of the day instead of dismissing them early right into this. Surprised LWX still hasn't put a WWA up for us though.

Looks like I've been under green echoes for most of the morning in the northern tip pf Calvert. Of course I'm not there so I don't have measurement.  Hope one of my neighbors post something on the snow.

11.1 just a few minutes ago.  If it's not going to snow, give me warmth.

19 minutes ago, psuhoffman said:

I’ve remained more focused on the “pattern” and perhaps more frustrated than some about the degradation of blocking because I have a hunch that we are unlikely to get a flush hit until that changes. We have seen this game before with epo driven cold where from range it looks snowy only to see the baroclinic zone shift north west.  Our best change would be early next week when the trough axis seems at its furthest east point but even then it’s a short window and when a storm does develop even during that window some guidance suggests it could be rain.  

The epo ridge is centered too far west to help absent any Atlantic help. Rare years when an epo pattern worked it was centered in western Canada not Alaska. Also if you look at examples like 2003, 2015, and 2015 the tpv elongated west to east not north to south and was situated in a way that acted to suppress the flow. That’s not true this time.   

Something has to change or storms will continue to cut then we get cold behind them. It could be the tpv but there are no signs of that either. It could be the NAO but every time it approaches it evaporates. Hopefully the flip really happens in Feb because I have doubts this pattern will work absent blocking or a change in tpv orientation. I guess the good news is both those things aren’t predicted well at range. 

Agree, the ridge the Pacific is too far west and then we get a big vortex /;negative anomaly over AK so we might even lose the cold air for a bit down the road.  Until then, looks like cold amd dry, or warm and wet when the cutters track to the west.  Something does need to change. 

3 minutes ago, Bob Chill said:

3k mostly agrees with its mentally unstable brother

Glad I'm not at Sterling.  I'd hang with the 06Z Euro as it's the NAM but wow.  The last two runs have been mega.  We've been NAMed. 

Storm Vista has 6 inches over DC on the Euro.  I thought this double jet streak structure was neat.  The left front juxtaposed with the right rear quadrant is a favorable combo for a moderate snowstorm and for potential banding.  

3 minutes ago, Bob Chill said:

Acceptable panel and nice jump from 6z...

stormvista has us in 6-8 on its snow product.  Wont' get excited until the Euro trends north.  The 06Z looked encouraging at its end.

2 minutes ago, H2O said:

This is what drives me nuts about this place at times.  Just a few days ago people were hopeful the puke pattern would improve and it was progged for the 13th.  A couple model runs showed a glimmer there might be a surprise before then.  So we go from this

to now a chance of this and you all are complaining?

 

It might be a poof but its not done and over by any means on tuesday.  

Plus the GEFS ensemble mean has shifted north and has 0,25" line on the city during on period. 

If you need a crummy model to hang your hopes to look at the 12Z RGEM.   I don't think it's right but will keep me looking at the GFS and Euro today.

1 minute ago, stormtracker said:

FV3 came north.  Gets us into the precip shield now

 

EDIT: Didn't check the 6z...about the same, but still better than the regular ol GFS

I think it is a tad wetter for us than the 06Z.  It's veery close to being really good and I'd take it. 

It does looks like we are almost dealing with 3 streams of flow.  The two more southerly features that interact and the northern stream flow over the northeast which needs to relax for us to get creamed.  For the Canadian to be right we need all three to react the way we want. The more northern of the two southern system to help pick up the system that is now coming into CA and lift it towards us while the northern stream lifts enough to allow the southern system not get completely sheared under it.  The GGEM does that and the parallel almost does it which allows it to give us snow.  Quite a cut off between the 0.50" liquid line and the nothing.  That makes for big forecast problems.  I've written a CWG article on the event but from reading all the comment here, everyone seems to understand the uncertainty and how volatile the model changes could be from run to run.  

3 hours ago, dtk said:

It's all part of our plan to get people to pay attention.  In reality, it is going to be dead wrong.

This is a pretty solid implementation, considering that we haven't had a chance to put a ton of new science into the package (outside of the model dynamics and MP scheme, a few DA enhancements, etc.).   For things like extratropical 500 hpa AC, it has gained us about a point (about what we'd expect/want from a biannual upgrade).  Improvements are statistically significant. 

I should caution, our model evaluation group has noted that there are times where the FV3-based GFS appears to be too progressive at longer ranges.  It's not clear how general this is and for what types of cases this has been noted.  

Thanks!

I wrote this on my Facebook page this morning.  I don't think any of the forecast problems outlined yesterday concerning the potential of a winter storm over the weekend have been resolved. The ensembles are not quite as bullish for snow as yesterday but there are enough members giving us moderate to heavy snow to not yet buy last night's (Monday night/early Tuesday morning) GFS and European runs which keep the bulk of the precip to our south. The parallel 06Z GFS still is a big hit and the Canadian model has the low tracking up the Chesapeake Bay introducing the possibility of rain. Those models and the heavier ensemble members argue to still keep all the options open ranging from the snow staying to our south to a significant (greater than 4" snowstorm) Besides, at these time ranges it's easy for the models to shift 100 miles north between now and Sunday.  My thoughts from last night's runs.  

8 minutes ago, dtk said:

FV3-based GEFS will not be implemented until early FY 2020 (probably Q2...e.g. about Jan 2020).  Some of this is driven by human and compute resources as there is a requirement for a 30 year reforecast for calibration before implementation.

Definitely 2017.  All official retrospectives and real-time experiment use the Lin-type GFDL MP scheme.

Daryl,  How do the FV3 scores compare with the GFS?  Right now I use it as another ensemble member.  

got a whopping 0.60" of snow and then the deluge started.  Not a good day, our thoughts two days ago were better than those yesterday.  Kind of a bust. 

The Euro seasonal does look really interesting.  While I'm not a big proponent of Nino meaning we end up snowy.  Such a 500H anomaly pattern would suggest enough cold air for Miller A type storms. 

Starting Saturday morning These are my COCORAHS reports

Sunday morning 7.20

Monday Morning 5.08

Tuesday morning 1.50

Wednesday morning 2.77.

My 4 day total was 16.55"  The heaviest 4 day stretch I can recall at my house. 

I haven't been around lately but still love you guys.  Wildfire Today has a cool video of a fire tornado transitioning to a waterspout.  Jebman, sorry about your dad. 

http://wildfiretoday.com/2018/07/16/fire-whirl-or-waterspout-or-fire-tornado/

My ranking

PDI

Feb 5-6 2010

Dec 2009

1996 blizzard

Feb 1958

March 1958

I remember having a long running thread on the pattern.  I know i had one for the Feb storm but think I also had one prior to this one as the pattern was a great one with the superens D+8 really pitting out a number of good storm analogs.   However,  the models kept the low suppressed until around day 3 when the ens mean had a 500 pattern almost identical to the DC 8" or greater composite.  Shortly after that I think Don Sutherland started comparing it to the knickerbocker storm. I tried finding the thread from eastern but could only find my thread on the feb 5/6 storm not the Deec one.