Rainshadow

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About Rainshadow

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  • Location:
    Mount Laurel, NJ
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    Golf and gardening and temperatures between 32F & 70F.

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  1. Weeklies didnt seem to follow suit. It just seems that both the GFS and Euro have been selling a wet bill of goods of soaking events (now not snow) beyond day 5 that become drier as we come closer.
  2. Williamsburg > Binghamton
  3. Protracted (well for the GFS) predicted pcpn event from the 25th thru the 27th was won by the new nam that was the driest and lost by the GEFs yet again. Reason why we only had three sounding runs for comparison was because the GFS never stopped precipitating. In this 60 hour sequence, the GFS had measurable predicted in 19 of the 20 three hour segments. It precipitated during three (9 hours) of them. new2016-7qpf.xlsx
  4. The 00z early this morning (28th) will be the last one we will need with this event.
  5. PHL had .11" phase I; a GEFS run had 1.10". We would have had to move the decimal point over one, to get the perfect forecast.
  6. Just as long as you are on the first tee at Kresson at 10 am on October 30th, all is good.
  7. I dont know about the labeling, but its not the old nam. From EMC site, I think its still whether they are using the 12km parent or 3km nest (that used to be 4 km). Changes to the NCEP North American Mesoscale (NAM) Forecast System Forecast model changes Horizontal grid resolution changes: CONUS nest from 4 km to 3 km Alaska nest from 6 km to 3 km CONUS fire weather nest from 1.333 km to 1.5 km More frequent calls of physics (now every 2nd time step for all domains); change frequency of radiation updates for the NAM 12 km parent domain from hourly to every 20 minutes Advect specific humidity every dynamics time step Mix out superadibatic layers Changes to Betts-Miller-Janjic convective scheme to improve 12 km parent QPF bias, especially during the cool season Updated Ferrier-Aligo microphysics to improve stratiform precipitation, better anvil reflectivity, reduce areas of light/noisy reflectivity over oceans Improved effect of frozen soil on transpiration and soil evaporation, leads to reduced cold/moist bias during cool season Radiation changes to reduce incoming surface shortwave radiation under liuqud clouds; reduces warm-season 2-m temperature bias Data Assimilation / Analysis Changes Replace 12-h NAM Data Assimilation System (NDAS, 3-h analysis updates for the 12 km parent domain) with a 6-h data assimilation cycle with hourly analysis updates for the 12 km parent and the 3 km CONUS/Alaska nests. The Hawaii/Puerto Rico/Fire weather nests will be initialized from the 12-km first guess at the end of 6-h assimilation cycle. Use of lightning data (from NLDN and ENL networks) and radar reflectivity-derived temperature tendencies in the diabatic digital filter initialization. Add execution of the diabatic digital filter initialization prior to the NAM free forecast (was only run during NDAS in previous ops NAM version 3). Assimilate new observation types: Aircraft data: Aeromexico, ADS-C, Air-Wisconsin New satellite radiance data: NOAA NPP (ATMS, CRIS), METEOSAT-10 SEVIRI, DMSP-F17 SSMIS; METOP-B AMSUA, MHS, IASI New GPS Radio Occultation data: METOP-B 3 (subtype) New satellite winds: Himawari-B, METEOSAT-7, 10 Imager WV AMV, NOAA-15, 18, 19 AVHRR IR AMV, METOP-A, B AVHRR AMV
  8. Has to be the new nam, ncep doesnt have the computer capacity to be running the older version.
  9. I know this explanation is dated, but the differences have always been there: WHY IS THE QPF DIFFERENT BETWEEN THE 12-KM NAM PARENT DOMAIN AND THE 4-KM NAM CONUS NEST? (4 Nov 11) The NAM 12km parent uses (as it always has) the Betts-Miller-Janjic (BMJ) parameterized convection scheme (Janjic, 1990 MWR, 1994 MWR). The NAM nests use a highly modified version of the BMJ scheme ("BMJ_DEV") which has moister profiles and is set to have reduced convective triggering, which leaves majority of the precipitation 'work' to the grid-scale microphysics (Ferrier). These settings for the nests in the BMJ_DEV scheme gave better QPF bias than running with explicit convection, and better forecast scores against upper-air and surface observations. So you should expect to see different QPF fields between the 12km NAM parent and the nests.
  10. Sun out here and up to 61, the high of the day.
  11. Those differences existed even before the upgrade, I am at a lost to explain the qpf differences other than they existed before March 21st.
  12. I don't know how they do it, but ncep is not running the old nam. I am wag they, tropical, are postprossessing the grib files to 12km & 32km.
  13. I think its just scaled to 12km.