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MAG5035

Meteorologist
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Posts posted by MAG5035

  1. 1 hour ago, Bubbler86 said:

    Yea, I am not think we need to head for an Ark Wed/Thur but it has been showing on models for several runs.  Some suites have Lanco a good period of rain.   I called it a clipper but really just a wave.  Unfortunately, I think it is part of our issue for Friday with lack of spacing, 

     

    Definitely one of the warmest Jan and Feb ever. 

    Yea that mid-week wave was what was bringing the frontal boundary down to set the edge for Friday. Friday’s event has been timing somewhat faster and the mid-week wave really hasn’t been pressing the front either. Spacing is definitely an issue, but so is the strength of Friday’s system. An already bombed out 976mb coming up the Mississippi out of the Ozarks isn’t ideal. It responds to the block and tries to secondary but the primary is too strong.

    There’s going to be some kind of a mix event for most or all of C-PA with this, but going to have to figure out thermals. Most guidance places a deep wedge of low level cold east of the Alleghenies all the way up through 850mb. Typically that’s enough to ensure what would be a significant period of front end snow, but there is prolific warm advection all the way up at 700mb (10k feet) due to the very strong 700mb low associated with the mature primary well west that would cut into that potential. That elevated of a warm nose would indicate to me sleet would be a predominant p-type for a while. I will say when it comes to the more mesoscale thermal features that are common around here I personally prefer the Euro when it comes to global guidance over the GFS… and then short range/high res stuff once it’s close enough. 

    So here was 6z Euro.

    Hr 87 temps at 925mb

    image.thumb.png.7df9575040ac25ce3306f345e09b327c.png

    Same hour at 850mb 

    image.thumb.png.348a6bdcc37927425e1cc9ebdf47be67.png

     

     

    Same hour at 700mb

    image.thumb.png.c9db8aab0c8698a2835eb4f9d66a3fd1.png

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  2. 29 minutes ago, canderson said:

    True, lots of rain tomorrow too. I just kinda meant I fully expect the trend of the warm out to win out Friday - it has for 30 or so consecutive months. 

    30 or so is a bit of a stretch, C-PA has had below average months as recently as October and December. This was 2022 as a whole.

    image.thumb.png.cab6135739103a42d34c7e05e58725cc.png

     

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  3. 13 minutes ago, Bubbler86 said:

    We have wet snow covered windows here.  East winds 30, 35 mph driving the slop into the side of the house.    Still probably over half rain but the parachutes sticking to everything.  Very heavy cell, with thunder and lightning, rolling through WV and Western MD.  Poking up above the MD line.

    That stuff on the doorstep to R-ville looks like it means business. 

  4. 15 minutes ago, Bubbler86 said:

    We continue to see snow mix in here with sleet and rain.  33.  Accums around the mulch.  Surprised this far west.   Winter storm number 1 this week.

    Here’s the current initialized HRRR temps at 850mb and 925mb. 

    850mb

    image.thumb.png.db7443b14f7875ac26cdb5f996aa1558.png

    925mb

    image.thumb.png.893c4cadbcf25a29bc3f55f35568a7f4.png

    Very marginal column up through 700mb but one that is a bit below freezing at the major low levels in eastern PA. The stuff that is currently pinwheeling into western PA and the Pittsburgh area is eventually the area of heavier precip that could drive a full changeover to snow for a brief period later tonight when that gets into the temporarily anchored low level cold temps east of the Alleghenies. That starts in the central counties roughly around UNV and I think that stays above Harrisburg mainly but since there’s some mixing pretty far south into the LSV we’ll have to see. 

     

  5. On 2/26/2023 at 10:36 AM, Itstrainingtime said:

    Would you say that this time frame is a little early in the pattern? I was thinking the following week or two might be a better chance as the pattern starts to break down. Next weekend still seems precarious to me as it will take perfect timing to avoid either suppression or a cutter. 

    To answer your question from yesterday, here was a portion of my post from a couple days prior back on Friday.. which actually also refers to a post the day before haha. My thoughts are usually around but they typically get buried when it gets active and the snowmaps start flying. 

    On 2/24/2023 at 4:01 PM, MAG5035 said:

    If we do end up hitting on that 3/3 event I’d actually consider it a bonus because even at that point we’re not set up in terms of the overall pattern other than the already established -NAO. The EPO/WPO nosedive starts occurring right after this event timeframe and most guidance doesn’t get the MJO back into 8 until after the first week of March. The result in the east is continued changeable weather in terms of temp anomalies and possibly even dealing with another cutter after the potential 3/3 storm.  When it does get back there, it appears it may be of a much stronger magnitude. I touched upon those things in my post yesterday and how I think the MJO loop back served to delay this big pattern change that I feel has to come at some point given eventual lining up of all these supporting teleconnections. 

    So with 3 days advanced since that post there’s no changes to that opinion although as I’ve mentioned the last couple posts for the late week event that I was really high on the potential. It’s crazy how sideways this went in the last 24-36hrs on the progs.. and the last couple days overall when the Euro had the main snow swath to the south of us. Storm gets too wound up too early. It’s going to hit the block and try to go to the coast but that strong primary is going to get west of us instead of sliding under us by the looks of it. The result is instead of honing in a mostly snow event for C-PA it’s going to be trying to figure out the degree of front end and mixing (sigh). I think if we stay as is with what most guidance has as the track today that we probably eventually correct to having some kind of a reasonable front end with resistance at the low levels, especially east of the Alleghenies. Global models have been presenting various degrees of mixing amongst various different scenarios of WAA aloft. That won’t start being resolved until we get into range of the short term/high res guidance. 

    At any rate here’s where we’re at this week during these two events

    EPO

    image.thumb.png.48c2d5bcf0b27e4ba2177e1e96d16ea7.png

    WPO

    image.thumb.png.bc9e535c2ad69a94c309d61297ada629.png

    MJO

    image.png.56d28f4e0190b15e201f815d90c674f0.png

    So first off, MJO is squarely in phase 7 during this timeframe, some of the other guidance touches all the way back into 6 the next couple days with the loop. Pretty much everything isn’t getting into 8 after the first week into March (generally 7th to 8th or so). Phase 7 MJO isn’t ideal for storm track as it still favors southeast ridging. Like I mentioned, we probably can get away with a weaker storm sneaking under us but not a wound up 970s low coming up into Missouri.

    The first two charts are the EPO and WPO, the gigantic reversal to negative doesn’t completely occur until pretty much the timeframe that the MJO gets to 8. This big shift occurs (and the MJO to 8) right after the late week storm timeframe. These are all the keys to the pattern change we’ve been looking for. We haven’t made it into 8-1 all winter in the MJO and the brief time the WPO was negative was the arctic discharge in December. -EPO has also coincided with our brief winter opportunities/attempts. So the fact that all those teleconnections are headed that way while the stratwarm induced high latitude blocking (-NAO) is already getting established probably bodes well for a cold/unsettled pattern setting up for us. The EPO/WPO flip allows for direct arctic sourced cold into the US which will press across the CONUS even with some western troughing (-PNA). 

    In the pattern related post I had before the above one I quoted, I was lamenting the fact that the MJO backtracking was going to delay this occurring. If it would’ve driven right into 8/1/2 I think we would’ve been rocking right now. Instead we’re probably talking mid month and onward. You can see the response of these aforementioned teleconnection flips in the longer range of the deterministic guidance/ensembles now.. not just the weeklies and extended GFS. There’s a cold period coming. It’s getting close though in the meantime this week, this current system tonight is going to finallly get NYC solidly on the board with a decent event. The interior upstate NY/New England  over to the top third to half of the 95 corridor is starting to catch up on snow departures. 

     

     

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  6. 13 minutes ago, Bubbler86 said:

    The Euro and CMC are Nesis storms next weekend...no posts?   I am starting to think that Grandmaster was right and the negative's have overtaken some.   They could be off their rockers but 5 days away! 

    Already issuing the it’s too warm for snow watches this week when it probably makes a run at 60ºF Wed/Thur ahead of this system lol. 

    I hate to be the counter to all the good model runs overnight as I’m pretty high on this storm threat for us but can’t forget the GFS/GEFS which is still running it’s track (mean track on GEFS) too high and it’s kind of went the wrong way for us a bit in the 0 and 6z runs for that. I’m sure there’s still front end in that scenario but I’m go big or go home at this point. Like I said recently, if I saw another snow to mix/junk system in the next 10 years it’d be too soon. This one’s going to have a big snowfall swath for someone, so hopefully it’s us. 

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  7. For the 3/3-4 event, it’s definitely starting to catch my attention with the Euro op starting to pick up on it the last few runs. GFS has been the most wound up of the bunch in terms of low strength, and today vs 12z the 18z has edged southeast a bit. Ensemble guidance has been painting pretty good support for a swath across C-PA that has been building.

    Trends, at MDT:

    Euro EPS:

    1962050033_ECMWF225.thumb.png.3ddfd0719dfca076e0c3e53f755f1f61.png

     

    GEFS:

    1721571713_GFS-ENS225.thumb.png.b01675ec4b8109651b5048a3c066b421.png

     

    Snow plumes at MDT:

    12z Euro EPS

    image.thumb.png.d9c1dd9c2bc7daea7fb8c2ec9bb6981a.png

     

    18z GEFS

    image.thumb.png.94f91e8ebdf01788453d2e04c833d1fc.png

     

    Several big hits in both ensembles and you can also see the difference between the two camps for Monday night with the Euro suite adding snow from that as well. The really big hits do drive up the mean but both ensembles are presenting most members showing accumulating snow and 18z GEFS has a little clustering of members in that 5-10” range. The thing with the GFS/GEFS suite is that it’s collectively more amped and rides that snow/mix line through PA. Early in the game for anything certain but I do like the signal for it. 

     

     

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  8. This Monday/Monday night thing is still fairly intriguing. The progged secondary low popping off the Delmarva acts to anchor solidly sub 0ºC 925/850mb temps east of the Alleghenies while the associated slug of precip crosses PA on guidance like the Euro/3k NAM while guidance like GFS/RGEM shows the same scenario but doesn’t quite pull in/anchor those kind of temps outside of about the NE quarter of of PA.  It kind of presents a similar scenario to what we saw Wednesday with the arrival of heavier precip delivering flakes to places it wasn’t even in the forecast. Secondary low is key in this circumstance. Front end mixing is probable in spots as well but the main potential occurs when the secondary gets going. This possibility is being brought by the developing blocky regime up top and a 50/50 type low.

    18z Euro by the hour:

    HR 57image.thumb.png.fe6e5f579a15824bc5f0fbb9ba6830fc.png

    HR 58

    image.thumb.png.f4da2bef2512ac5974d74f9d02d89155.png

    HR 59

    image.thumb.png.bef22b8a53e2f67d30c8a2cb95dd0479.png

    See how the column aloft responds by cooling as the secondary low develops. These are also hourly plots. That darker blue is heavy 1-2”/hr type snowfall rates. So what’s on the table is after the front end mixing/frozen that probably favors interior central and NE PA (where this might be an all snow event) is a 2-4 hr period of heavier precip that flips to snow as the coastal gets going. And then also sort of similarly to last Wednesday, once this coastal moves away… we lose the column and eventually surface temps moderate going into later Tuesday and mid-week. But that’s after most or all of the precip is done.  The warmth won’t be nearly as prolific as last week obviously.

     

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  9. Regarding the 3/3 event, the Euro op might be doing it’s best GFS impression being the most progressive at the moment but the Euro ensemble mean does indicate there’s some support for the more robust GFS/Canadian type solution. The individual low tracks that make up that mean are definitely not anything resembling clustered but there is enough among the members to yield a half decent precip mean across PA considering range. 

    image.thumb.png.9832e0486bb677690c0916941df75911.png

    I do think this particular event presents the best legit threat of a widespread wintry event in awhile for us but I like to reel this thing in a good bit further without it ending up heading to the lakes in the process before I get super confident about it.

    The much closer Mon-Tues event also bears a bit of watching as well. That one will depend mainly on development of the secondary low. Euro was the most aggressive developing a noteable secondary in VA to the Delmarva. The result was keeping mixed/frozen in NC/NE PA with the threat of some icing further south into central PA. I see that as more of an interior C-PA threat either way in the best case scenario given the alignment of the primary already in the lower lakes and the secondary developing a bit late. NE PA probably in the best position in terms of PA locations. The other aspect to that system would be preceding cold on the front end but there’s not much high support. Though low 980s primary to the lakes attacking a 1020ish high in Ontario is still a half decent gradient. Overall, preceding cold isn’t much to write home about but it may still bear some watching for the front end for some ice in spots. 

    If we do end up hitting on that 3/3 event I’d actually consider it a bonus because even at that point we’re not set up in terms of the overall pattern other than the already established -NAO. The EPO/WPO nosedive starts occurring right after this event timeframe and most guidance doesn’t get the MJO back into 8 until after the first week of March. The result in the east is continued changeable weather in terms of temp anomalies and possibly even dealing with another cutter after the potential 3/3 storm.  When it does get back there, it appears it may be of a much stronger magnitude. I touched upon those things in my post yesterday and how I think the MJO loop back served to delay this big pattern change that I feel has to come at some point given eventual lining up of all these supporting teleconnections. 

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  10. 39 minutes ago, Itstrainingtime said:

    Back to MAG's post and QPF numbers - the GFS and Euro agree that Mammoth CA receives between 8-10" of QPF over the next 7 days...all of course, will be snow. And, they're talking about 20-1 ratios according to the local NWS office. Mammoth Mountain now feels that with the amount of water content in their current snowpack plus what's coming over the next week, they'll be skiing into at least the middle of July if not August. (that would be without any snow after next week which is HIGHLY unlikely.)

     

    The current base is 13' at Main and 20' at the summit. 

     

    I'm sort of excited for my trip. Starting to wonder if we'll have travel issues heading up CA 203 into Mammoth if this keeps up. 

    I still can’t over higher elevations of Los Angeles and Ventura Counties getting 2-5 FEET with isolated 7-8’ possible this weekend. What a winter in the SW US and Rockies. 

    I think it was LA NWS’s first issued blizzard warning since 1989. 

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  11. 3 hours ago, Itstrainingtime said:

    Another reason why I don't like snow maps - there are many types of maps available, and it's easy to cherry pick (unknowingly I'm sure at times) a map that either shows a lot of snow or very little. I think all of it creates both confusion and hard feelings. Some maps include sleet, some do not. I think some are based on different ratios than others. And then, there's the positive snow depth maps, which to me at least would seem to be what matters most...when the storm ends, just how much snow is going to be on the ground...

     

    Here is the 6z GFS positive snow depth map - copy paste from our neighbors to our south so it only includes the southern tier (sorry folks north of the turnpike) but for a model run that "looked" like a pure or mostly pure snow event...this looks very underwhelming: (it's a 1-4" event for us. and the storm has moved out at this point)

     

    I typically don’t even bother with +snow depth maps as I don’t think they’re really meant to be applied to actual event snowfalls. It seems like those guys use them the most and it’s kind of the same mentality as saying “well it was warm the day before so the snow isn’t going to lay on anything”. The GFS has over an inch of QPF in 6 hrs in that DC-Baltimore corridor that’s mostly conditional snow. Obviously the D8-10 disclaimers aside, If that actually happened as modeled (which looked to be 2”+ hr rates for a few hours at one point), there’s absolutely no way you’d only have a plus depth change of 1-4” at the end of the event as it has for that area. 

    It is a lot to consider with all the different snow maps.  I warn in here at least once or twice a season about using TT snowmaps in particular since they include sleet/ice with the 10:1 snow totaling. But each method has their flaws/limitations and it’s important to know what kind of setup you’re looking at when trying to determine the best snow map to use for a given area for an event. Do we have marginal temps aloft in the column? Abnormally cold temps? Climo (which is >10:1 in Jan/Feb in C-PA), etc, etc. For example, given the marginal nature of literally every single snowfall that has come our way this winter in our general area…I’ve been mostly paying most attention to whichever map was less out of Kuchera vs straight 10:1. Typically, the Kuchera calculates higher than 10:1 around here. But since temps (surface and aloft) have been so marginal and warmer than average climo in the snow events that have materialized in C-PA…it’s been putting out less than 10:1 in most circumstances in our region this winter.

    For that D8-10 event, The 8-12”+ the straight 10:1 puts out in DC-Baltimore corridor is more of a 6-9” on the Kuchera (implying <10:1). I think that’s more than reasonable considering what the model is outputting in terms of conditional snow and temps. The 10:1 is reasonable too, really. Neither of those methods involve actual dynamics related to snow crystal growth. You can be 32ºF at the surface but if the lift is in the right spot in the snow growth zone aloft inside a death band you can still put down much greater than 10:1 ratios. Using the right snow map is definitely not a perfected science haha. 

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  12. 40 minutes ago, pasnownut said:

    Looking over how things are progressing toward EOM and into Morch, I've gotta say that the 3/4 storm that is showing up on guidance has my interest, as the tellies are starting to support something in that "window".  AO/NAO headed solidly negative, and MJO looping from 7 to 8 in that timeframe would give this window some merit.  Just gotta believe the MJO progreassion that is being shown, and while it can change, it has changed over the last few days...and for the better i might add.  IF it verifies, it is enough of a pronounced move to MAYBE get us into the goods.

    GFS MJO index forecast phase diagram

    I’m not a fan of the MJO backtrack loop back into 7, which serves to delay what I think is has to come at some point. We are seeing the fruits of the stratwarm event propagating into the troposphere with the developing blocking that eventually retrogrades into a nice -NAO block and overall blocking over the top. PNA remains solidly negative on all guidance, even on the farther ranges of the GFS extended and Euro weeklies. We’ll have to contend with some degree of western troughing and continued relentless - temp anomalies biased toward the western half of the country. I think the real change for us comes after the EPO and WPO reverse to negative… which guidance has been showing happening during the first week of March. Extended guidance then keeps those teleconnections there. If/when that sets up, the combo of that and the blocking over the top via the -NAO should put us into a decidedly colder and more favorable regime for snow chances despite the -PNA. I felt a progressive MJO pulse that continued into 8-1-2 without looping would have driven that kind of change much sooner. But I think we’re going to contend with it sooner or later. The hope is it’s soon enough to salvage some decent snow opportunities without it being too offensive to the spring crowd. 

    In the meantime, we’re going to continue to be vulnerable to cutters and in and out cold shots as there is ample cold available on our side of the hemisphere now. Big beneficiaries of the developing -NAO blocking the next 10-15 days without the implied Pac help (EPO/WPO) would appear to be upstate NY and a good portion of interior New England.   Deterministic ensemble guidance is indicating that some of those folks are going to go a long way towards recouping a lot of their big time snow deficits. 

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  13. 16 minutes ago, Bubbler86 said:

    Captain of the column cooling you are.   This system will go down as one that trended colder as it got closer. 

    I’ll say lol, it’s pouring snow right now. Might as well get what will prob be the only snow pic of the month in. First measurable since 1/31.
     

    Splotchy roads caved

    57BB2D9C-C996-4441-927B-F2E340F51284.thumb.jpeg.4ae458a87397fd2fff5c47e80bacb5a3.jpeg

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  14. 16 minutes ago, Bubbler86 said:

    Blizzard Warning....

     

    for Los Angeles County, California. 

    #Snowtown #BaseState #NewNormal lol

    LOX’s discussion is pretty fun. Also mentioned in their full discussion in addition to 2-5feet of snow above 4k feet is the possibility that downtown LA goes 8 consecutive days without cracking 60ºF if the temp forecasts are correct. 

    Quote
    All eyes on Thursday night through Saturday morning when a slow
    moving fetch of moist dynamic SSW flow moves over the area. This
    system will bring a broad swath of moderate to locally heavy rain
    and snow the area. This precipitation will be further enhanced by
    the orographic uplift provided by the south flow and transverse
    ranges. Snow levels will fluctuate quite a bit as the southerly
    flow will raise levels to about 4500 ft briefly on Friday
    afternoon. This could create a mixture of rain/snow at the I-5
    Grapevine area before precipitation turns back to all snow Friday
    evening. Rainfall rates will range from 0.50-1.0" per hour near
    the main precip band on Friday bringing a threat of urban flooding
    and issues near recent burn scars.
    
    The precipitation totals for the majority of the south Santa
    Barbara coast, Ventura, and Los Angeles coasts/valleys will be in
    the 2-4 inch category. Low snow levels will mean that this could
    be the largest amount of 24-48 hour snowfall seen in decades
    (likely rivaling the 1989 storm) for our Ventura and Los Angeles
    County mountains. Depending on the snow-line, rainfall in the
    foothills will be from 4-6 inches, but the mountains above 4000 ft
    could see upwards of 2-5 FEET of snow with isolated amounts to 7
    feet at higher elevations. Snowfall of this rate and amount could
    lead to damage to structures and trees with an immense threat of
    avalanches, especially in the eastern San Gabriel Mountains by
    Saturday.
    
    While the main precip band will exit the area Saturday morning and
    the steady rain will stop. But then the upper low will move
    directly over the area. 500 mb temps are near -35 degrees C which
    will make for a very unstable atmosphere. The cold, unstable air
    will be conducive to development of heavy showers, lightning, and
    small hail or graupel. Cyclonic spin would allow for waterspout
    activity over the ocean with brief small tornadoes near the coast.
    Precipitation coverage would not be as widespread, but most areas
    are likely to see additional showers through the day Saturday and
    snow levels will remain below 3000 ft.

     

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