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About heavy_wx

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  • Four Letter Airport Code For Weather Obs (Such as KDCA)
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  • Location:
    State College, PA

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  1. Some flurries out there this morning.
  2. KH waves are beautiful! Here's a particularly dramatic example from Alabama a few years ago: Basically they form when there is a vertical gradient in wind shear and/or temperature. A small, random disturbance can then grow to produce the waves; these waves are visible to us if the temperature and/or shear gradients occur near the tops of clouds, as the cloud basically traces out the waves. They're actually fairly common on fair-weather days after a cold frontal passage if you look out for them.
  3. Still snowing here with modestly reduced visibility. Mostly wet surfaces out there with decent-sized melting aggregates.
  4. Light snow here now.
  5. We had some brief melting sleet here as well.
  6. Yeah, correlations are pretty meaningless without rigorous statistical tests to determine the likelihood that such an outcome is distinguishable from random chance. Crudely, if you look at griteater's SAI performance evaluation for the last 19 years, 11/19 times positive SAI has occurred with negative AO. That seems like an outcome totally consistent with random chance, and therefore implies minimal dependence of the winter AO on SAI.
  7. 52/36 and calm right now. It wouldn't surprise me to see some frost here tomorrow morning.
  8. Around 6:30. Once they posted that they had Doubleganger, people freaked out. Luckily I was still able to pick up some.
  9. I drove to the Cape from PA today; low 80s and sun until hitting eastern CT. Then it clouded up to light/moderate rain down 495 and route 6. Of course I had to stop at Tree House being on the way and just off of I-84.
  10. I think that's a bit generous. There are quite a few years where the Tug Hill doesn't see a 50" event if you look through this nice archive: http://www.weather.gov/buf/lesEventArchive?season=2016-2017&event=A
  11. The high ZDR at >5 kft indicates a pretty strong updraft capable of lofting big rain drops. If you look at the higher tilts, that enhanced ZDR is still present just above the melting layer so in some ways it is similar to a ZDR column in a severe thunderstorm. KDP is also enhanced there as well.
  12. Could definitely be a kind of "chicken or egg" effect.
  13. It could, several previous studies mentioned in this paper (http://journals.ametsoc.org/doi/pdf/10.1175/MWR-D-11-00349.1) suggest that an outer eyewall can reduce the outflow region of the inner eyewall and thus reduce convection in the inner eyewall. This process has been linked to eyewall replacement cycles. In any case, I think it is important to note that intensification is generally easier when there is a single, highly organized eyewall. If you look at the radar image below, you can see that the inner eyewall is still a bit ragged and surrounded by a secondary eyewall.
  14. Yeah the greatest low-level convergence is to the WNW along the coastline due to frictional contrast between the land and ocean. That effect would seem to favor a continued short-term hugging of the coast. You can see in the surface obs and radar plot below that there is some relatively dry air (73F dew points) over southeast Cuba. The closer surface stations may have malfunctioned, but we can probably expect that dew points closer to Irma's center are comparable, especially given the downslope flow off the hills in central Cuba. It will be interesting to see how quickly the center of circulation can move away from the coast and get more favorable latent heat transport into the storm.