Jump to content


  • Posts

  • Joined

  • Last visited

Posts posted by jwilson

  1. 10 minutes ago, TheClimateChanger said:

    Smelling the rain never works here because the warm tongue always wins out - if not at the surface, aloft. We do much better staying all snow and potentially exceeding forecasts when we're on the western fringe of a storm forecast to dump 12"+ in central PA. The precipitation shields often seem to expand further west or at least linger out this way longer than expected.

    Respectfully disagree somewhat, although I understand your point.  it all depends on the orientation of the baroclinic zone and the development of the low itself.  We smelled the rain yesterday and got to see some of the biggest snowflakes ever, which also led to the overperformance.  When storms are pushing in from our southwest or south and running due north or NNE it's one thing, but in a progressive flow, we'll only be borderline for a brief period with the cold pushing in quickly.  Thus there's no threat to changeover.  This isn't a case where the system continues to deepen as it gets too close to us.  In this case, the low deepens only as it gets further away.

    You need to be close to that rain-snow line in such a fast moving system or you miss the best snowfall rates.  Granted, you'd be right if the low intensifies too quickly in the south and is then pulled too far west along the boundary, but for now that doesn't look like the issue we're facing.

  2. GFS has been pretty stable in placement, but right now that's the high end event and it's "only" 3-6" for most of the area.  CMC is similar.

    The NAM came back a bit west from its highly progressive 6Z run, but the changes at 500H are quite subtle.  Really we just need that s/w to dig further west/south earlier.  The timing of that intensification is the only thing that's really going to matter in this fast flow.  I think the NWS went a little too high with their initial estimations, we've seen that before.  If I was the NWS, I probably wouldn't have issued a total yet at all.  The NAM is too jumpy right now to be reliable and a 5-7" call doesn't have much support at mid-day.

    The issue is the best frontogenesis stays east of Pittsburgh from the beginning on current model runs.  If the best rates manage to slide east of us at the onset, that's when you know it's going to be a low-end event.  We gotta smell the rain.  It's such a progressive storm there's no room for error if you want to see a higher total.  But right now pretty much everything is on the table.  After yesterday, as well, we can't discount a surprise in either direction.

  3. If winter and cold is what you're still after, you can sort of hold out hope for now.  There's no more 50 degree days in the long-term until around March 5th.  It barely touches 40 over the next two weeks.  That warm-up is also like the others: two days and then back into the freezer, with ample cold dumped into the U.S. (likely due to that strengthening -EPO).  That could change, of course, but for now, as long as cold is around, it leaves an opportunity for snow.

    I'm personally ready for an early spring, but it looks like we're going to hold onto winter for a while longer.  If we can't eek out more snow in the pattern, that would have to be considered a disappointment.

  4. I don't love the trough alignment for the system next Friday.  The longwave pattern screams cutter to me.  Ridge too far west off the pacific coast.  Not that it can't change, but for now that would be the concern if you're still looking for snow.  The Euro and Canadian take a slightly different tact in not intensifying the central LP as deeply and it basically skirts a boundary nearby.  Seems much less likely than a cutter.

    That said, the pattern looks a bit more conducive coming into March.  Pretty similar look to January.  The only issue is that's basically fantasy land.

    Long-term, who knows.  OP GFS wants to sink the PNA and flood us with warmth, but a fairly strong -EPO may assist in continuing to push cold air down into the CONUS.

  5. I'm good with some down time from tracking after January.  It was almost constant since New Year's.

    At this point I'm chasing the big one and that's about it.  It's been at least six years since we've even sniffed the two-footer, same for places further east of us which seems like a semi-drought given recent climatology.  I don't have high confidence of one occurring this year.  We don't have the right kind of blocking setup.  I would say next year looks slightly more promising with a Nino prediction.

  6. I have a friend that's a meteorologist in a southern market and did his thesis on public communication related to weather broadcasting and forecasting, etc.  It's pretty interesting how he approaches his forecasts, and I think it's something a lot of on-air mets (among others) miss.  There's not enough discussion about the nuance of storms, really.  And I realize the "general public" is overall kind of dumb so you can't wade too far into the minutiae, but I think a lot of mets skip over the grey-area talking points and focus too much on black-and-white numbers.

    This does vary by forecaster, however.  We even see the local NWS has good discussions and bad ones.  I'm guessing there are not enough college-level courses on communication in this context, and some people are better communicators than others, naturally.  Regardless of how you felt about the last couple storms, there were obvious issues that some mets didn't really touch on or discuss enough.

    I see some of the same things here on the board.  I wish we would ban Kuchera snowfall maps because those things fail to verify 99% of the time.  It only serves to create unrealistic expectations.  Actual precip forecasting requires multi-level and layer analysis.  Same with attempting to discern ratios.

    (I'm being mostly facetious here with that Kuchera point, but I do think those maps should be largely ignored.)

    • Like 2
  7. At this point, I'm just hoping the models are under-developing surface warmth.  Looking at the NAM, for example, we'd be talking about significant icing.  The kind of ice that threatens power outages and tree damage, among other things.  12-18" of frozen precipitation and almost none of it is snow.  A fairly thick warm layer from 700-850 for most of the duration.  Maybe that dryslotting could help cut back precip totals, as well, but pretty much all the models have us approaching 2" of total precip.

    With snow mostly off the table, I'd rather have plain rain.  The lower-res models show more of a sleet bomb.  Pretty rare to get measurably accumulating sleet.

    • Like 1
  8. 2 hours ago, Mailman said:

    Hard to be optimistic with this sort of setup. At least for me, anyhow.

    I agree.  The cold air is moving in too late.  If we had that high about 12 hours earlier, we might be in the game, but there's a rather large sleet signature for anything that isn't rain.

    The 12Z GFS, for example, shows 10" of sleet or ice.  That's the period where the 850 temps are still above freezing.  The GFS might be 3-6" of snow on the backend.  Big IF, though, and the GFS is the absolute best show for us right now.  Every other model is less generous.

    The look at 500H isn't one of a "big snowstorm," either.  The trough alignment is awful.

    I think our best hope is this system resets the trough for energy behind it giving us a better shot at snow.  The GFS tries to show this with a ball of energy on Monday, but even right now I'd say it's not quite right.  Goes negative too soon.  Won't analyze it further, though, because we have to wait for this FROPA to go through.

    • Like 1
  9. It looked like the heavier bands really struggled to make it across the Delaware, for the most part.  My mom's place in Hatboro has like 4-6" but evidently it's quite windy and the light, powdery snow has been blown around easily.

    With all these NS coastals and La Ninas, it might be time to get a shore place as a snow cabin.  :mapsnow:

  10. 7 minutes ago, kpantz said:

    SREF plumes for total snow have gone up in E PA (KABE) if you compare 21Z to 15Z.  Seems to be something else on which to hang ultimately dashed hopes. :)

    I was just looking at those myself.  Rooting for you guys to score; one SREF member has 30" for PHL.  Better ride that one!  Mean is 8.31" in Philly.  That's almost double the previous run.

  11. 2 hours ago, Rd9108 said:

    I appreciate your analysis and wisdom but you crush weenies hearts lol.

    Haha, I promise it's not intentional.  I try to be realistic about things.

    Ironically, the 18Z GFS got really close to the NAM solution and continued the trend from the previous two runs.  There are still very subtle differences, with the ridge being slightly steeper and elevated on the NAM, while the GFS wants to tamp it down some.  The trough is also broader on the GFS than the NAM, which seems to push the surface low development just slightly off to the east and north.  We're talking OBX versus Cape Fear, a pretty minimal variation.  Both genesis the low off Jacksonville, FL.  The GFS wants that rapid NE movement, though.

    I guess this is where I have a knowledge gap because I honestly don't understand that surface depiction from the GFS.  To me, the energy is actually even better consolidated than it was at 6Z Monday, which was the tightest coastal solution the GFS has shown of late.  If you compare the trough between the two, the 18Z run today has dug fairly significantly further south.  The 540 line is over Huntsville, AL as opposed to Bowling Green, KY.  Especially if you saw these two runs side-by-side, you'd look at the 500H today and almost certainly think, "that's turning the corner and would be the better outcome."

    But it doesn't.  I'm having trouble understanding why.  Maybe the ridge out west being just a little flatter above Boise is enough?  Is the 850 low too far to the east and needs captured?  For now those are my only theories.  The way it looks at 500, I think, would result in some more northward pull, unless that 850 gets off the coast and moves everything with it?

  12. 19 minutes ago, dj3 said:

    Nam at range looks decent for a 2-4 event maybe more. More expansive precip zone.


    I would definitely take some early overrunning snows as the low deepens offshore, even if we miss the wrap-up.

    That said, it's a classic 84-hour NAM signature.  Must be part of its programming.  At 0Z I'll expect this to be 250 miles offshore and much drier.

  13. I'm shocked people are trusting the Euro to get this right.  It's been beaten consistently by the GFS over the last month.

    There were two runs yesterday where it looked like you might get consistency, only for the models to immediately relent on the phasing and make it a Nantucket special.  The setup remains quite precarious, with a delicate phase required to get anyone south of Boston into the snow.  That's likely why you'd have to favor it not happening.

    That said, the trends over the last three runs have been to pull in that southern energy more and more leading to an earlier phase, rather than leave the energy elongated and lagged in the west.  The differences in 12Z from yesterday to today are quite subtle: more shallow ridge out west and a trough that's a bit too neutral and open.  The Canadian solutions are a little more obviously contrasted, but the 12Z run from yesterday for that was an extreme solution and always unlikely.

    I would ride the GFS for this one and unless it goes back to an earlier phase and a steeper ridge position, it's probably game over outside of coastal New England.

    • Like 1
  14. It's way too soon to talk details on this, but next weekend's event - as currently depicted on all the models - looks somewhat similar to the one earlier this month.  A northern-stream s/w dives below the trough and amplifies in the southern states.  Due to the early cut-off and bombogenesis, chances are higher than normal that this storm would ride a similar path up along the Appalachian trail.  However, the GFS attempts a solution where another piece of energy in the NS acts as a kicker/barrier.  The Canadian slows down the event by phasing a more substantial piece of southern-stream energy with the northern, and instead of being a kicker, that lagged or second piece of energy acts as a fuse.

    Unsurprisingly, the CMC version of events gets pulled further west and would potentially be a bigger hit to our area.  It could also be too much of a good thing like the last storm, and with no confluence up top, it would get pulled too far west resulting in another messy solution.  The GFS timing might miss our area altogether and ride the coast.

    The Euro also shows a storm that's probably closer to the GFS in timing/evolution but is more an inland runner.  3/3 at this lead-time is unusual, so there's little doubt it's something to put in the back of your mind for now.  I do notice that none of them show a traditional block or high-pressure placement as seems to be the trend lately.  For now it's not a big deal, but an important detail later.

    The questions will come down to timing, wave spacing, confluence, and how much (if any) southern-stream involvement.

    • Like 2
  • Create New...