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Showing content with the highest reputation since 03/26/2018 in all areas

  1. 18 points
    Lightning got one of the oak trees at the course
  2. 18 points
  3. 16 points
    Hey folks, long time no chat. How's it going? Since ZR is in the mix for most I just thought I'd pop in and share this paper with you all: https://journals.ametsoc.org/doi/full/10.1175/WAF-D-15-0118.1. This is the research behind the FRAM (Freezing Rain Accumulation Model) that the NWS uses. (Or at least, in Central Region we use. I can't speak to those living the Bohemia lifestyle 😉.) The gist is that ice-to-liquid-ratio, ILR, is often actually even less than 1:1. The FRAM is a function of 1) rain rate, 2) wind speed, and 3) surface Tw. Rain rate shows the most robust statistical relationship. And it might not be what you think. Higher rain rates decrease the ILR - see Figs. 10-12. Remember that there is latent heat released when liquid freezes on contact. More liquid freezing at a time means more latent heat release and thus more warming of the surface. Secondarily, a higher rain rate also means more splash-off and thus less of the liquid remaining as ice. As for the other factors... more wind helps to transport that heat away from the surface and thus increases the ILR. For Tw, the relationship is non-linear, but as you can see, the peak ILR occurs with a surface Tw of around -1 to -3 C. That means a surface temp of 32.0 F usually doesn't cut it. Even 30-31 F can be iffy for significant ice accrual. So if we were to believe the NAM (famous last words), in Philly you're getting most of your ZR in the optimal temp range, so that's a plus for significant ice accrual. You should also have a 10-15 knot wind, which helps. Buuut a big chunk of the precip is coming while rain rates are still pretty high. Looking at the NAM in BUFKIT, I'm seeing a rain rate around 0.1"/hr during the hours where the Bourgouin gives ZR. That may end up really limiting the ice accrual - the median ILR for that rain rate is 0.5, and the innerquartile range is ~0.3 to 0.65. So all in all I'm not ready to bite on a major ice storm just yet. Now that said, I was also really bearish on the November snow event, so... 🙃 P.S. We'll cross 100" on the season up here by the end of the weekend. Sitting at 99.1" right now, with 19" on the ground. Continuous snow cover since November 9th. And this is entirely normal!
  4. 16 points
    I will first handly admit I was totally wrong about this storm and writing off these bigger totals just from a climo stand point and just how close soundings were. 9 times out of 10 with a sounding as marginal as that leading up to this event you don't come out the way we did. Throw in the fact we snowed above 546 thicknesses and also the mid level warmth was denied advancement till late. I think thats why I enjoy weather because there is never a given, it's always a variable and unpredictable. All in all some of those snow maps obv were way over done, but the euro's kuchera was solid and the eps did a fantastic job. Once I saw the nam last night with it's thermals and that fgen I knew if we could stay could enough it could overperform. I really knew this morning when I saw DC snowing and sticking.
  5. 15 points
    I was truly overcome with emotion this holiday , my only child gave birth to a handsome ( Looks like me ) baby boy on 12/17. I'm now a proud Pop Pop!
  6. 15 points
    best porta potty pic I've ever taken....just had 2 very close bolts near us in delco
  7. 15 points
  8. 15 points
    After grabbing all your data and Coocorahs stuff and applying some common sense in sparse areas, came up with this.
  9. 14 points
    Wouldnt put my guard down NW of the fall line (ie @Qtown Snow), despite some sobering (for weenies like me) output from key models. Historically, our more significant ice storms occur with less than ideal timing and placement of surface features. We have an extension of the primary high pressure, located north of the UP of Michigan, starting in a good spot for cold air draining in Quebec, but retreating NE as the low approaches. This develops some CAD, however, it's short time in a good position limits the depth of the cold pool, as noted by dew points in the teens and twenties, rising as the high retreats and low approaches Many ice events have primary lows riding up into the WV area. As the primary rides up the western side of the Apps, and warm mid-level air rides over the Apps, and the shallow pool of cold air to the east, we typically see an inverted trough form along the coast. A difference between the colder NAM and warmer Euro are the depiction of the inverted trough placement. The EURO essentially indicates the CAD is so shallow/weak it's not feeling enough of an influence, so the cold is scoured more readily, thus reflecting a farther north inverted trough/baroclinic zone (where warmer ocean air meets CAD). This has merit as the cold pool was not well established. NAM on the other hand holds onto the CAD longer and shows a more pronounced inverted trough and farther south baroclinic zone. To the south of the inverted trough are warm southerly surface winds. To the north are cold NE surface winds, that typically lock in colder temperatures. See the difference in the inverted trough plavement and effevt on surface wind direction: In these marginal setups, PHL typically turns to rain. Far NW locks in cold longer than expected. Im not sharing anything new here, I wanted to highlight the importance of the inverted trough placement. If NAM thermals are closer to reality, that NE surface flow will bring quite a mess, here's a sounding at the height of the precip to reflect it
  10. 14 points
  11. 14 points
    Bangor PA — 6” as of 9:00 AM
  12. 13 points
    Just got internet back. A good pounding this PM with at least one more round to go. Gusty wind, a few close strikes, and prolonged heavy rain. Never seen the little creek behind us so high. 5.40" today - 7.16" 2-day
  13. 13 points
    Here is a pic of the Hail from last night in my backyard. The initial clouds were mesmerizing the way they were swirling within each other. I was in a restaurant when the golden light hit and didn't get to take any pictures, but the colors were beautiful. Fun evening.
  14. 13 points
  15. 12 points
  16. 12 points
  17. 12 points
    Not quite sure in which thread it is most appropriate to post this... Some pics of yesterday’s (8/14/18) storms taken in Newtown. Some good visuals considering that, to my knowledge, these storms were not severe-warned. The first one was a pretty cumulonimbus flaring up in the early afternoon. The others were the second line of storms that came through around 5pm. The last one almost looks like a supercell with a tail cloud but of course it isn’t.
  18. 12 points
  19. 12 points
  20. 12 points
    Now that NOAA Workforce Management has (finally) cleared me, I can announce that in June I'll be starting at NWS Marquette, Michigan! That's right, I'll be a Yooper! As I move from Lawn Guyland to Da Yoop, I'm excited at all the new opportunities and blah blah blah but I'm most excited about adding a new hideous accent to my repertoire. Their snow depth for the season went to 0 on May 1st. Next +NAO/-PNA La Nina winter I'll mail you guys a cooler full of Lake Superior's Finest™.
  21. 12 points
  22. 11 points
    Man a lot of jumpers already. I mean I'll be there soon but not till saturday
  23. 11 points
    A few pics from beautiful West Caln Township today.
  24. 11 points
  25. 11 points
    Just was going to post this. Mine have never been bigger. Some nearly 6’ tall. Got a shot of the bunny (phlox in background) who has been enjoying my yard. Luckily, primarily just the clover in the grass. Oh, just had to throw the comparison winter shot (March 21) in