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Isotherm

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Everything posted by Isotherm

  1. Getting crushed here today. 1 inch of rain already. Training cells directed over my area.
  2. The background state is certainly a not insignificant factor inculcated in the overall long range forecast equation, from my standpoint.
  3. The SSTA profile similarities b/t present [2019] and late May 2002 are quite striking. The degree of structural symmetry is impressive, on a hemispheric and even global scale.
  4. Thanks, Roger, and I concur, [while the language was qualified somewhat due to long range precautions] I saw some distinct signals for potential major heat. Good luck with your forecast as well.
  5. Summer outlook can be found here: http://www.lightinthestorm.com/ ***Scroll down for temperature/pcpn departure forecast details and maps, as well as 90F day forecast. NJ map of total snowfall for the 2018-19 winter: http://www.lightinthestorm.com/nj-snowfall Comments and/or inquiries are appreciated.
  6. @IrishRob17 @40/70 Benchmark, That is correct, I am not advocating for the once per day observation -- which is much different than capturing the maximum snowfall for the 24 hour period. Ray, to be clear, I am merely presenting the guidelines as they currently stand, which states that non-airport measuring should be maximum snowfall for the 24 hour period. I am not advocating that the 6-hr clearing is necessarily a bad method. I just think congruence with historical records is important and we never should have added the option for 6hr clearing in the 1998-2012 period. Per my discussion with Matt who works with the NJ climatologist, there was extensive debate among the people on the panel for this 6hr - maximum snowfall issues. Interestingly enough, the person who pushed most for the 6-hr method was the same person who reversed his thinking and signed off on the return to the maximum snowfall method. Snow measuring is an inexact science; there are arguments for both methods.
  7. I concur with this too, I think they should have maintained the maximum depth standard.
  8. Agree, and I'd argue the once per day observation is the least accurate of all for sure. The clearing/vs maximum depth should be fairly similar in most storms that aren't > 32F at the surface.
  9. It's definitely a mess now. I'm not sure why there aren't clearer instructions disseminated.
  10. Correct. This is per Matt G who works with the State Climatologist. "One final thing regarding this past event. We did receive a 31.0" storm total snow report in Kinnelon (Morris County, NJ) that no doubt got at least a little attention, as it would represent, as far as I know, the largest event total in NJ from the storm. I checked in with the observer, and he confirmed that he cleared the board 3 times mid-storm to reduce the effects of compression. Unfortunately, that makes his inflated measurement invalid, at least in the context of the current guidelines (though even with the 6 hour rule, this must have been more like 1 hour clearings), so we've nixed the value. BTW, I'll personally be working on crafting a NJ snowfall map tomorrow based on hundreds of reports received. I post it here when complete."
  11. Prior to 1998, it was max-depth unless instructed. I think max depth would maintain more congruence w/ historical record. I've previously provided reference to the current NWS guidelines. I checked with the NJ State Climatologist, who specializes in snow cover and was very much involved in the crafting of the guidelines. What he was able to explain to me was that traditionally, the six hour option has only been available to professional observers at airports. However, back in about 1998 the NWS rules were revised and the six hour option was added for Coop observers*.
  12. Per the NJ state climatologist: "When things were reconsidered in 2012, the 6-hour option was removed except for "when instructed." Now, I'm not sure of the frequency of this usage, but apparently the 6-hour option is not in use, only when instructed to do so by the NWS (usually airport).
  13. They're not supposed to as per official guidelines. They should be taking intermediate depth measurements to capture maximum depth. Unfortunately, there is a ton of miscommunication on this issue. NWS airports do use it sometimes when advised (See last post).
  14. Just as an FYI, the latest NWS/COOP guidelines for measuring snowfall are to take the maximum accumulation of new snow in a 24 hour period. The 6 hour clearing method is no longer in effect, unless specifically instructed to by a NWS office (airports sometimes). See the following: section 3.1 and onward http://www.nws.noaa.gov/os/coop/reference/Snow_Measurement_Guidelines.pdf The following is courtesy of Matt G. who operates with the New Jersey State Climatologist, regarding the official guidelines: I've previously provided reference to the current NWS guidelines. I checked with the NJ State Climatologist, who specializes in snow cover and was very much involved in the crafting of the guidelines. What he was able to explain to me was that traditionally, the six hour option has only been available to professional observers at airports. However, back in about 1998 the NWS rules were revised and the six hour option was added for Coop observers*. This was despite the protest of several people on the committee, as a higher up (I won't name names, but any snow weenie will know the name well) overrode them. When things were reconsidered in 2012, the 6-hour option was removed except for "when instructed." The same fellow who brought about the 6-hour allowance, oddly enough, signed off on the removal of the 6-hour option. All that said, the biggest debate on the committee related to the snow->melt-> snow in a single day situation, the same occurrence that has been argued about here. Ultimately, the compromise was made to simplify the guidelines and call daily snowfall the maximum accumulation achieved during a day, period. There's arguments to made both ways (and it sounds like there were among the experts on the committee), but ultimately, the guideline is objective, consistent, and most in line with historical practices. All that said, from what I've seen as a heavy user of Coop data and a state coordinator for CoCoRaHS, far and away the most common "problem" with snow measurements is that many observers (and from what I've seen, perhaps the majority of non-airport Coop) take their measurements once daily at ob time without making any attempt to capture the maximum accumulation. This is probably not a new issue, as I bet it's been relatively common through the years. But sometimes the differences between maximum accumulation and ob time measurement can be significant, so this is something I gently remind volunteers about, with the understanding that many are unable (e,g., at work or sleeping) or unwilling to take these extra measurements (some Coop sites, for instance, are businesses or municipal operations centers, thus not manned all day). It sucks, but we live with it. As for frequent board clearing, I suspect it's a relatively rare occurrence, though people still assert that the 6-hour clearing rule is the standard. I would not be surprised if even some NWS employees are not aware of the current guidelines (hopefully most are). It just won't die. One final thing regarding this past event. We did receive a 31.0" storm total snow report in Kinnelon (Morris County, NJ) that no doubt got at least a little attention, as it would represent, as far as I know, the largest event total in NJ from the storm. I checked in with the observer, and he confirmed that he cleared the board 3 times mid-storm to reduce the effects of compression. Unfortunately, that makes his inflated measurement invalid, at least in the context of the current guidelines (though even with the 6 hour rule, this must have been more like 1 hour clearings), so we've nixed the value. BTW, I'll personally be working on crafting a NJ snowfall map tomorrow based on hundreds of reports received. I post it here when complete. This is a good debate to have! Thanks for sharing your thoughts. * A note about Coop stations. There seems to be some confusion about what constitutes an "official" report, which is subjective in the first place. The airports are first-order stations that also double as Coop stations. The remainder of Coop sites are manned by volunteer observers, and their data also constitute "official" records in my mind, in that they make up the permanent climate record of the US and are quality controlled and archived in NOAA's NCEI GHCN-Daily dataset. For that matter, so now are CoCoRaHS data (if you are a CoCoRaHS observer, your data are a part of the weather/climate records archived at NCEI!).
  15. Turned out much better than it seemed it would a couple weeks ago. Maples are mostly past peak here now, but still holding great color, and oaks are now peak. I think we'll see major leaf drop with the CAA event at the end of this week.
  16. Still going to end up a bit high on NYC/LGA/TTN, pretty close on PHL/EWR. Happy with the call overall.
  17. Cooling degree days have been the lowest probably since 2009 for our area. I only have 766 CDD's for year thus far, quite low comparatively after the past couple summers.
  18. Agreed on all counts. Those numbers will almost certainly be too high. And yeah, definitely feeling much more fall like in terms of sun intensity now. Really noticing the lengthening nights.
  19. 16 here now. We're pretty much done given the upcoming pattern. Might be able to make the average of 18 for around here.
  20. I like where I stand with my pre-season predictions; might even end up a tad aggressive for some areas: PHL: 28 EWR: 25 NYC: 16 LGA: 19 TTN: 21
  21. 3, 5, and 7 here for May, June, and July respectively. Total 15. So far nothing in August, and it looks like nothing for awhile.
  22. 94F and day 14 for the season here.
  23. I'm tied with Newark (doubt that will last) at 12 90 degree days here.
  24. Up to 22 days here, above the normal of 17-18 I think. I had 38 in 2010. We should manage some more days in Sept.
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