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DISCLAIMER
Regional Atmospheric Soaring Prediction
BLIPMAP FORECASTS
For Great Britain
Using a locally-run WRF model with 4, 5 & 12 km horizontal resolution and 52 vertical levels
BLIPMAP = Boundary Layer Information Prediction MAP
Created by Dr. John W. (Jack) Glendening, Meteorologist 

http://drjack.info

RASP Demystified, an article by Rebekah Sherwin, a hang glider pilot. Published in the March 2012 edition of Skywings, the magazine of the British Hang Gliding and Paragliding Association (BHPA), it is reproduced with permission of the author. Webcasts on using RASP, including an excellent introduction to Soundings. Done by some Paraglider people, they are hosted by Judith Mole. Many Thanks to you all.
Weatherjack's excellent Tutorials are still available. Some papers by Jean Oberson, a RASP maintainer in Switzerland.
Note there are functional differences from RASP-UK
Tephigrams - What you need to know.

From the Black Mountains Gliding Club Ground School, by Gordon Dennis
How to use RASP - What you should know

Apologies for the old Logo!
Notes and Caveats:
  • One is not supposed to believe all the details of these forecasts, particularly since the smallest-scale structure is constantly changing yet only a few snapshots at different times are shown.  Rather, one should be looking for patterns.
  • Forecasts for points close to the boundary will be less accurate than for those located nearer the center of the domain, due to inevitable mis-matchings between the coarse and fine grids. In particular, predictions of max/min BL vertical velocity are very noisy and inaccurate near the boundary (particularly where boundary condition problems exist). To remind users of this, a dotted line marks the "frame" outside of which coarse-fine boundary interaction problems are most prevalent. 
  • The "Explicit CloudWater Cloudbase" estimates are based on cloud water predicted from internal model equations and are problematical since there is no simple criterion for differentiating "mist" concentrations from "cloud" concentrations.  The criterion presently used is a first guess. 
  • The "Cu Potential" and "Sfc. LCL" predictions are based on a simple formula which considers only water vapor at the surface
  • This model does not ingest as much observational data as do the institutional models such as RUC and ETA, hence some effects are not included. 
  • The fact that these forecasts are only a snapshot in time of a fairly noisy field should be particularly emphasized for the 2 km resolution forecasts, as forecasts for, say, 30 minutes before or after would look different.  At this point it's difficult to figure how much value they really add anything, but one never knows til one tries. 
  • The "Vert. Velocity at 850mb (or 700mb or 500mb)" and "Vert. Velocity Slice" parameters attempt to forecast mt. wave events, although strong vertical velocities resulting from deep BL convergence can also be found in the plots.  The first parameter gives a plan view of vertical velocity at the 850mb level, a height of roughly 1500 m MSL and thus often above the BL top.  The Cross Section parameter (available as a pop-up) is a vertical slice taken parallel to the wind direction at the 850mb level A label above the plots gives the location and direction of the slice.  Mt. wave predictions are best made using resultions no larger than 4km, since a coarser grid generally does not resolve the waves accurately.