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LAPS is a data assimilation system bringing a variety of datasets (widely available and customized) into numerical models (e.g., MM5, RAMS, WRF) for the production of very detailed analyses of local weather conditions and short-range forecasts. The portable system supports a broad clientele of government and military entities, universities, and international weather agencies. This includes federal and state agencies (e.g. NWS, USAF, DOD), private sector (e.g. Precision Wind), academia (e.g. Univ of HI), and international (e.g. Taiwan CWB). LAPS blends a wide variety of global, national, and local datasets (e.g. METARs and mesonets) into analyzed grids. LAPS analyses are used to initialize various forecast models (e.g. WRF, MM5, RAMS), running on local-to-global scales. It utilizes large-scale numerical weather prediction models as backgrounds for both analyses and prediction, and has adjustable horizontal, vertical, and temporal resolution. LAPS is highly portable and efficient and can be run onsite using inexpensive hardware - desktop to laptop. This allows the user to assimilate their own observational data and set up the analysis configuration to their liking. LAPS is designed to excel in rapid update analysis and short-term forecasts, with good agreement to observations.

The data from local meso-networks of surface observing systems, Doppler radars, satellites (radiance and high-resolution imager), wind and temperature (RASS) profilers, radiometric profilers, as well as aircraft are typically incorporated every hour into a three-dimensional grid covering a 1040km by 1240km area. LAPS has analysis and prediction components. The analysis component has two options, "traditional" and variational. A numerical forecast model initialized with LAPS analyses is run to provide short-term forecasts. We produce ensemble forecasts using multiple models and initialization methods, with verification. We have several online LAPS presentations.

LAPS Domains

LAPS Real-time Analyses and Forecasts Image Products

Figure: Current analysis of temperature and wind from LAPS running a 500m resolution updated every 15 minutes.
Domain covers parts of Colorado, Wyoming, and Nebraska. Click on the image for a more detailed view.

LAPS is run in real-time at GSD for a domain centered on the Denver, CO Weather Forecast Office. Analysis and forecast output is often shown at the daily weather briefings. LAPS is an integral part of the Hydrometeorological Testbed (HMT), as well as the Hazardous Weather Testbed (HWT). LAPS was used in support of the 2002 IHOP experiment. We are modeling and studying a 2008 tornado in Windsor, CO .

LAPS has been ported to many locations, including academic institutions such as Univ. of Oklahoma ("OLAPS"), Univ. of North Dakota, and Univ. of Hawaii's Mauna Kea Weather Center. LAPS is running on-site at each National Weather Service Forecast Office (WFO) as an integral part of AWIPS (the main computer system that weather forecasters use). We are also running the system externally to AWIPS at WFOs in Miami, Lubbock, Fairbanks, Sterling, Monterey, Reno, and Davenport. Our software is being ported and/or being run at ESRL to support various US government agencies such as Atlantic Oceanographic and Meterological Laboratory, Range Standardization and Automation (RSA) at the U.S. Space Centers, National Ocean Service, U.S. Forest Service, as well as state and local government agencies like the California Dept. of Water Resources. We are working in support of renewable energy in the areas of wind and solar power.

We also work with international government weather agencies in countries such as China, where the Institute of Heavy Rain has installed LAPS in fourteen Chinese meteorological centers. Other agencies using LAPS are located in Italy (CNR-ISAC), Taiwan, Korea, Spain (METEOCAT), Finland (FMI), and Serbia.

LAPS Users

LAPS Downloads: Less than six months ago   Less than two years ago   More than two years ago  

Forecast Centers, NWS AWIPS and Non-US (squares) , , etc
Distributor locations (triangles) , etc

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