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Isotherm last won the day on November 17 2019

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About Isotherm

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    Veritas Vos Liberabit

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  1. This will be my final post on this topic of discourse. 1) The CPC holds the official NAO data. The monthly data is calculated via their method, and these are the data utilized by most in the meteorological community: https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.nao.monthly.b5001.current.ascii.table 2) Whether you personally believe the CPC data is incorrect - is an entirely different discussion. But for the purposes of having official data to reference, the CPC data was the provenance of my comment re "no -NAO episodes so far this December"
  2. It has not been proven wrong - that is false. If the CPC method depicts entirely positive NAO, and the z500 anomalies depict positive NAO, that is cross agreement. Why is the CPC method cherry picked, but your source is not cherry picked? That line of reasoning does not make sense. Regardless, it is a trivial point, as this is a red herring from the actual forecast for the mean state D and DJF. Finally, I am not going to invoke other names, but there were many talking up (and forecasting) a colder, active/snowy December.
  3. I remain confused as to what the argument is -- both 500mb height anomalies and CPC, or the data you provided, suggest +NAO overall for December. Even if there have been brief periods of higher heights developing near Greenland -- it didn't rise to the level of negative NAO per the datasets or z500 means. So, I'm not exactly sure what it is certain people here are asking from me, admission wise -- as if I'm on trial. I have already stated the deficiencies to date temperature wise in the NE US, and gone over the positives of the forecast globally/hemispherically. Why aren't the calls of others
  4. I disagree in the characterization of Davis Strait Block. If it were a block, mid-level ridging would not be expansive across the E CONUS next week. I utilize the data provided to us by NOAA; again, an objective barometer against which to compare.
  5. Yes, and the CPC data, which is widely accepted in the scientific / meteorological community indicates not one -NAO day this December so far.
  6. December 1st is the initiation point for the formula. How can formula be developed if not based on existing datasets? Those snowfall maps are NJ State Climatologist produced, and derived from the NWS and trained spotters. The call was never for a snowless month. Re temps, I stated in the post - will bust too warm for the NE US for December; departures likely finish near normal. The rest of the country looks good, and as far as the major indicators, generally on track, except there was more NPAC ridging than anticipated initially.
  7. The NAO calculation is not only the Davis Straits. The spatial domain includes the region extending from Greenland down toward the Azores. This is what my formula is derived from.
  8. Also, remember I never said, 'no -NAO episodes' either. The forecasted mean +NAO is for the average mode for D-J-F. So that includes periods of negative, and in fact, I think February will average -NAO.
  9. First panel is near neutral, and the bottom one could potentially be slightly negative [and that is reflected on the CPC forecast near the end of December]. While there are some higher heights near Greenland, it's not an effectual block, and if you widened the view to the NHEM, one would see that the entire geopotential height snapshot in the NAO spatial domain is very mixed. So -- yes -- that does not scream -NAO to me at all.
  10. Here's a description of the CPC technique. https://www.cpc.ncep.noaa.gov/data/teledoc/nao.shtml The resultant z500 thus far is fairly typical +NAO w/ low geopotential heights over Greenland and the sub-tropical high to the south.
  11. z500 Dec 1-20 is clearly solidly positive NAO, as well. Note that the NAO calculation is Iceland-Azores. This is fairly classic +NAO.
  12. Even if you were to utilize that method, the NAO has averaged solidly positive for December thus far. Look at the analysis plots - it went positive around the 1st, then strongly positive, and has briefly dipped slightly negative per that plot. So average positive thus far. Regardless, what matters is the DJF mean anyway, but the NAO has averaged positive to date.
  13. Colin -- thank you, and I agree. Happy holidays to you, too.
  14. The data on the maps is derived directly from trained spotter submissions to the NWS. So, take up the issue with the NWS and the other trained spotters if both of you are skeptical of all of the totals. The data indicates the vast majority of Monmouth County does not have more than 4.5" total. Most are likely in the 2-4.5" range. There may be lollipops slightly higher in Marlboro-Holmdel as noted. Three events: Monmouth County... Howell 0.4 in 0903 PM 12/18 Trained Spotter .Monmouth
  15. Jason, Thank you for your respectful reply -- it's much appreciated. I think your points are valid re how the information is conveyed, and this was partially the point of my post to a certain extent -- that there seems to be some underpinning (whatever one wants to call it -- but certainly not an air of friendliness) toward those who have a differing viewpoint. Disagreements can and should be encouraged -- I have always believed that, and agree. My only ask is that discussion is honest, professional, and respectful. Tom
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