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  1. Past hour
  2. Since 1950, 28/39 (72%) of 6" or greater snowstorms that commenced during the January 1-February 15 period had a PNA+. That figure falls afterward as wave lengths begin to shorten.
  3. Generally, yes. Note, the JMA is also south of the 18z GFS as well.
  4. Aren’t we getting a quick spike in the PNA which gives us a small window for that storm?
  5. This is awesome!! Better winter weather than up here LOL!!
  6. - PNA, rare 6 inch snow in NYC. I believe 70% ish ? Of 6 inch snows had POS PNA's ?
  7. Today
  8. For those who are interested, these were the 500 mb height anomalies for the January 31-February 1, 1878 snowstorm, which brought 7.0" snow to New York City:
  9. After a cold start, especially outside the City where temperatures fell into the teens with some single digits (Danbury reported a 6° low and Poughkeespie had a minimum temperature of 7°), temperatures rose into the upper 30s in the region.   Temperatures will likely run above normal through the remainder of January. However, a mild finish to a very warm January does not mean that February will likely be warmer than normal. The coefficient of determination for New York City between the January and February temperatures is just 0.07. Records go back to 1869.   Colder air could return during or just after the first week in February.   As long as the Arctic Oscillation remains strongly positive, the risk of widespread significant snow (6" or greater) from Washington, DC to Boston remains low. Since 1950, there were 11 storms that brought 6" or more snow to 2 or more of the following cities: Boston, New York City, Philadelphia, and Washington, DC. Just 1 such storm occurred when the AO was +1.000 or above. Therefore, through most of the remainder of January, the greatest risk of moderate or significant snowfall will likely exist for central and upstate New York and central and northern New England. The pattern could begin to grow more favorable for snow on the coastal plain during the beginning of February should the Arctic Oscillation (AO) fall toward neutral levels.   Before then, a storm could bring 0.50" to 1.50" precipitation, mostly or all rain, to Washington, DC to Boston this weekend. A moderate snowfall with some locally significant amounts could occur across central and upstate New York, central and northern New England, and parts of southern Ontario.   The ENSO Region 1+2 anomaly was -0.2°C and the Region 3.4 anomaly was +0.4°C for the week centered around January 15. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.22°C and the ENSO Region 3.4 anomaly has averaged +0.52°C. The remainder of winter 2019-2020 will likely feature neutral-warm to weak El Niño conditions.   For February 1981-2019, the following monthly temperature averages were recorded for cases when the ENSO Region 3.4 anomaly averaged 0.00°C to +0.75°C:   ENSO R1+2 Anomaly < 0: AO+: NYC: 36.9°; Philadelphia: 37.6° (n=101 dates) ENSO R1+2 Anomaly < 0: AO-: NYC: 34.7°; Philadelphia: 34.9° (n=97 dates)   ENSO R1+2 Anomaly > 0: AO+: NYC: 35.7°; Philadelphia: 36.6° (n=82 dates) ENSO R1+2 Anomaly > 0: AO-: NYC: 30.9°; Philadelphia: 31.6° (n=58 dates)   February 1981-2019: NYC: 35.8°; Philadelphia: 36.0°   The SOI was -6.17 today.   Today, the preliminary Arctic Oscillation (AO) figure was +1.544.   No significant stratospheric warming event appears likely through January 30. Wave 2 activity will remain relatively suppressed. Overall, most of the stratosphere is forecast to remain cold on the EPS.   On January 21, the MJO was in Phase 7 at an amplitude of 2.044 (RMM). The January 20-adjusted amplitude was 2.153.   The MJO had recently spent 9 consecutive days at an amplitude of 3.000 or above. There have been only 8 cases where the MJO had an amplitude of 3.000 or above for 7 or more consecutive days. The shortest period from the start of that stretch that saw the MJO's amplitude fall below 1.000 was 20 days. The mean period was 36 days. The longest period was 55 days. Based on this historic experience, the MJO likely won't reach low amplitude until near or after the end of January.   Since 1974, there were 8 prior cases where the MJO reached Phase 4 at an amplitude of 1.500 or above in the January 5-20 period. In 7 or 88% of those cases, the MJO progressed into Phases 7 and 8. The MJO moved into Phase 7 on January 20.   Based on sensitivity analysis applied to the latest guidance, New York City has an implied near 100% probability of a warmer than normal January. The monthly mean temperature could finish near 39.0° in New York City.   The probability that January 2020 will finish with among the 10 highest January average temperatures on record has increased to just over 60%. The 10th warmest January occurred in 1906 with a monthly mean temperature of 38.4°. The 9th warmest January was January 1949 with an average temperature of 38.6°.
  10. Navy continues to be wayyy suppressed for both systems. Like moving across Florida suppressed.
  11. G-Rated site @RoaDawg. Also...the GEFS is run off the old core, and is NOT the FV3. Completely different model.
  12. I’d still favor NW but I could see the coast get in on one of these if it does take the right track.
  13. Yesterday
  14. you haven’t slept all winter and have 1.6” to show for it With that said I’m hopping on board for this one, I need some excitement in my life
  15. Unfortunately there are no matches to the upcoming 500mb pattern
  16. For early February reference, below are the 500 mb height anomalies for snowstorms that brought 6" or more snow to Boston, New York City, and Philadelphia (all 3 locations) during the February 1-15, 1950-2019 period. Storms that commenced prior to February 1 or continued after February 15 are excluded. One typically found a Greenland-Hudson Bay block and/or a PNA+ ridge coupled with a trough in the East. The variation on a case-by-case basis should also be noted.
  17. The dreaded 36F Rainer in KC. Oh well we’ve had it pretty good so far.
  18. Do you know what 10 days of Anthony in here waiting for this solution to verify. He will never get that out of his mind.
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