A primary advantage to use of model analysis grids is the collection of a much larger sample of storm cases in a shorter period of time, since fortuitous positioning of an observed sounding is not necessary for a particular case. These grids do not incorporate sub grid scale processes associated with individual supercells however the grid point data can be “contaminated” by model generated precipitation during the model assimilation time period, or by direct observations within precipitation areas at the 0-hour (hereafter 0-h) model start time. Thompson (1998) attempted to circumvent storm induced sounding effects and small sample sizes of observed proximity soundings by using Eta model analysis grids. Additional discussion of problems associated with proximity soundings can be found in Brooks et al. Based on discussion by Maddox (1976), and the personal experiences of the authors, an exceptionally long period of time must pass before a sufficient number of “representative” soundings can be collected. Second, supercells are essentially randomly distributed with respect to the observed soundings, making consistent data collection difficult at best. (1998), which can complicate the choice of a proximity sounding location. Supercells can exert an influence on the local vertical wind profiles, as discussed by Weisman et al. First, there are questions regarding the most relevant location for a supercell proximity sounding. However, observed soundings in near-storm environments present at least a couple of problems. Numerous studies have used so-called “proximity” soundings to diagnose various aspects of severe storm environments, including Maddox (1976), Davies and Johns (1993), Kerr and Darkow (1996), Rasmussen and Blanchard (1998), and Bunkers et al. Observed Soundings in Supercell Environments
#Icycle r8uc update
Thompson/Edwards 20th SLS Conference Article (RUC-2/Raob Comparisons)Īdapted from Preprints, 20th AMS Conference on Severe Local Storms, Orlando, Sep 2000Ī Comparison of Rapid Update Cycle 2 (RUC-2) Model Soundings with