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About aperson

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  1. PWATs and theta-e ridge all the way down into the Bay of Campeche are very impressive. This thing is a moisture cannon.
  2. I'm going to have to end my spree of relentless lurking to chuckle at calculus being an "integral skill". Tautologically true!
  3. HAARP

    This thread should be a canonical example of Confirmation Bias
  4. Winter 2017-18 Medium/Long Range Disco

    GFS has been giving a moderate signal for a sudden stratospheric warming in the 1.5-2wk range for a bit over two days now. While there's likely going to be a strong mediation of Arctic air toward the Siberian instead of Canadian side, I think there is a good chance for a -AO outbreak starting around the end of the month.
  5. MJO is updated through yesterday here: http://www.bom.gov.au/climate/mjo/ I personally expect a slow pattern due to ridging feedbacks from low Arctic sea ice extent around the Bering Sea.
  6. Cross Hemisphere ridge

    The pattern appears to be a strong +DA (dipole anomaly), e.g. the second mode of the Arctic Oscillation's EOF (see fig 2: http://onlinelibrary.wiley.com/doi/10.1029/2008GL036706/full). This article posits that sea ice loss on the Pacific side generates a teleconnection that results in this sort of pacific ridging behavior: https://www.nature.com/articles/s41467-017-01907-4
  7. Potential Energy Flux

    While investigating the Arctic warm anomaly intrusion into the Bering Strait I found December 1, 2007 to be a good analog of December 23, 2017. In particular, similar MJO phase 7 exit with high zonal available potential energy results in a similar 500mb geopotential height configuration in the Arctic. Both have a loose wavenumber 5 configuration, and Arctic 2m surface temperatures are very similar for each case. I think you may find other analogs by searching for strong MJO Phase 7 exits around Nov-Feb. I used this paper as the source for Dec 1, 2007 and for looking for MJO correlates: http://journals.ametsoc.org/doi/10.1175/JCLI-D-15-0502.1
  8. Tropical Storm Jose

    Looks like a bifurcation around day 3. The north group are (almost) all recurving out to sea. Substantial variability in the south group.
  9. Tropical Storm Jose

    Is the dprog/dt trend you're talking about the successive weakening of the ridge that's occurring in these runs? I assume that if this trend continues the system will be steered toward landfall by the low pressure system. https://www.tropicaltidbits.com/analysis/models/?model=gfs&region=us&pkg=z500a&runtime=2017091106&fh=66&xpos=0&ypos=80 https://www.tropicaltidbits.com/analysis/models/?model=gfs&region=us&pkg=z500a&runtime=2017091112&fh=60&xpos=0&ypos=80 https://www.tropicaltidbits.com/analysis/models/?model=gfs&region=us&pkg=z500a&runtime=2017091118&fh=54&xpos=0&ypos=81
  10. Major Hurricane Irma- STORM MODE

    This system's extratropical transition is making a very big rain threat to the NE coast of FL into GA. Many flood gauges in JAX at major flood stage now: http://water.weather.gov/ahps2/index.php?wfo=jax
  11. Major Hurricane Irma- STORM MODE

    Is the blowup in windfield and precipitation related to the extratropical transition of these systems? Irma is interacting with that cold front while still at a very low pressure.
  12. Major Hurricane Irma- STORM MODE

    No idea. I'm way too much of a hobbyist to know to what extent terrain and water buildup effects could contribute to BOE here. My naive opinion is that the pass near Lake Okeechobee helped prevent a more rapid weakening.
  13. Major Hurricane Irma- STORM MODE

    Indeed. WV loops show bursts of convection both near the center of circulation and in the huge feeder band that's building: http://weather.cod.edu/satrad/exper/?parms=meso1-13-96-1-10 That feeder band is out over high CAPE (3k+ to 4k+ the whole way) water and is rapidly turning this system into a significant rainfall event for the NE side of FL. I've been keeping my eye on JAX loop and flood levels: https://www.wunderground.com/weather-radar/united-states/fl/jacksonville/jax/?region=pie&MR=1 http://water.weather.gov/ahps2/index.php?wfo=jax&fcst_timeframe=0&current_color=all&current_type=all&fcst_type=obs&conus_map=d_map&center_point_lat=30.609549999999484&center_point_lon=-82.2711189999986&default_zoom=8&marker=false&refresh=true
  14. Major Hurricane Irma- STORM MODE

    A met posted on here a few days ago something that really cleared this up for me. The motion path of hurricanes is trochoidal: https://en.wikipedia.org/wiki/Trochoid Think of taking a top that is moving forward and then lightly blowing on one side of it in the same direction as its rotation
  15. Major Hurricane Irma

    Does NAM have any validity whatsoever at tracking the steering of a tropical system? When watching Harvey it seemed useful for synoptics and precipitation behavior, but it constantly missed the track of the system.