Real-Time Weather Forecast

(TEMPORARILY NOT AVAILABLE )

Welcome to the Real-Time MM5 Weather Forecast page at University of Houston.

This project is the first stage of our Air Quality Forecast System under development. This project is to provide meteorological data for the Air Quality Model.

The core part of this project is so called “The Fifth-Generation NCAR / Penn State Mesoscale Model” (MM5). MM5 is the latest in a series that developed from a mesoscale model used by Anthes at Penn State in the early 70's, which is a limited-area, nonhydrostatic or hydrostatic (Version 2 only), terrain-following sigma-coordinate model designed to simulate or predict mesoscale and regional-scale atmospheric circulation.

The forecast system includes downloading NCEP ETA forecast data , MM5 pre-processing data, parallel MM5 simulation, data visualization, and publishing through website or exporting to other application the forecast results. The whole processor is automated and scheduled by a set of Unix/Linux Shell and Perl scripts.

The machine involved in this system includes:

• HPC Sun Cluster of Excellence (Galaxy Cluster) at University of Houston
  Parallel MM5 numerical simulation, the most computational-intensive, time-consuming part, is running on this cluster in parallel mode.
• Math Department Linux Machine
  The rest of the forecast system, including pre-process, post-process (visualization) and web server for the forecast results publishing is placed here.
• Computer Science Web Server
  Because at the time we build the framework of this forecast system, the web server on the math department machine does not support CGI usage for ordinary users, two CGI programs are running here, which will generate individual each visualization image and animation dynamically upon user’s request.

Between different machines, SSH and SCP utilities are used with the scripts to invoke programs remotely and transfer data around.

While the Weather Forecast System is already running on daily bases, we are also trying to use EZ-Grid tools developed by Dr. Barbara Chapman's research group for this inter-hosts resource management purpose here. We believe this could be a good experiment for grid computing study.

Currently, with the kind helps from HPC Center people, we are now able to run forecasts four domains with 24-hour simulation each (figure 3). The highest resolution is 1.3 km for the finest fourth domain. The length of each forecast cycle is one day. Each cycle starts the beginning of the day and run for one day to give out forecast data for the day following tomorrow. Sun Cluster of Excellence COE from University of Houston HPC center is used for our daily MM5 parallel simulation. A system called Grid Engine is responsible to manage jobs, like submitting job and assigning computing resources, among the computing nodes of this SMP cluster . Because the forecast nature, the numerical simulation part must be finish within 24 hours after the job is submitted to the computing node. Some quota of time to run the pre-processing and post-processing should also be considered. With current domain setup and maximum time step 90 allowed for the job, each forecast cycle now can be guaranteed to finish in one day before another cycle starts by running parallel simulation part on COE. After suffering a long-time torture of the CFL errors, we realize the FORTE7 compiler suite is the must to run MM5 on our Sun Cluster.

Real-Time Weather Forecast website address:
Under Construction