The intended purpose of the real-time analyses and forecasts of the quasi-geostrophic (QG) diagnostic equations web page is to provide an interactive tool that can be used to enhance classroom education and/or weather discussions in both the academic and operational environment by providing visualizations of core QG dynamical equations.
The calculations and visualizations are produced using NCAR Command Language version 6.6.2 on computer resources at the NOAA National Severe Storms Laboratory and the University of Oklahoma. All fields are computed using 12-hourly pressure-level data from the Canadian Meteorological Centre (CMC) Global Deterministic Forecast System forecasts available in GRIB2 format at 0.24×0.24 degree latitude-longitude grid spacing. The raw CMC global forecasts are read using information at every third grid point and then are smoothed using a 9-point local smoother run 80 times to produce cleaner results for the QG diagnostics. A detailed description of the fields displayed on each set of images is provided in the Users’ Guides and as captions on the animations themselves. While every attempt is made to keep the images up-to-date, it is possible that there will be interruptions to the image generation services as system updates occur.
Each animation provided at the links below includes a 20-day analysis archive and the most recent forecast out to 144 hours. Images older than 20 days are not retained.
***Image generation was interrupted 11-16 February 2020 as CMC changed available output resolution of their model data. Thank you for your patience as the 10-day analysis archive repopulates.
1. Sutcliffe Development Theory: (click here for Users’ Guide)
2. Petterssen Development Equation: (click here for Users’ Guide)
3. Height Tendency Equation: (click here for Users’ Guide)
4. Omega Equation: (click here for Users’ Guide)
5. QG energetics: [Lackmann (2011) pp. 57-65]
| 500 hPa height and height perturbation from zonal mean|
500 hPa height and geostrophic wind perturbation from zonal mean
500 hPa height perturbation from zonal mean and ageostrophic geopotential flux vectors and divergence
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