The link to the website is:

http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis

Part I - Mission Connection

The National Centers for Environmental Prediction (NCEP) Mission

NCEP delivers national and global weather, water, climate and space weather guidance, forecasts, warnings and analysis to its Partners and External User Communities.

These products and services are based on a service-science legacy and respond to user needs to protect life and property, enhance the nation's economy and support the nation's growing need for environmental information.

Description of the Product

In July 2001, NCEP launched a new internet website devoted to meteorological forecast graphics from the output of NCEP's forecast models. Currently, four of these models are used to make graphics-the Eta, the AVN, the MRF and the NGM. Seven different graphics are produced for each model at each time-step.

NCEP is planning several enhancements to this website over the next several months. These enhancements will include two new domains and additional total precipitation graphics. More information about these enhancements is available in Part II of this document.

The forecast graphics are available on the internet at the same time products from these models are available to National Weather Service and private users. This is because the website is updated as each model forecast hour is completed. No unique graphics are made as all graphics are similar to those routinely created for NCEP weather forecasters.

This website can be reached from a link on NCEP's home page:

http://www.ncep.noaa.gov/

Connection to NCEP's Mission

The NWS focuses public resources on our mission to protect life and property. We also recognize that information and products generated in the normal process of performing that mission belong to the public. It is our policy to facilitate easy access to the information we generate in the course of our work.

This Website provides a clear, single point of entry to access standard graphics from each operational model in a format commonly used by NCEP and field forecasters. The creation of this website is consistent with U.S. government policy to make all data in the public domain easily accessible through the internet.

The major users of the website are the general public as well as governmental organizations, universities, and businesses.

The graphics are available on the internet for viewing or downloading. In addition, an ftp site is planned (available March 2002) to make quick downloads of multiple graphics possible.

Comments

We are always seeking to improve our products based on user feedback. Comments on the NCEP model website may be addressed to:

National Centers for Environmental Prediction

5200 Auth Road

Camp Springs, MD 20746

ATTN: Lauren Morone Rm. 101

e-mail: Lauren.Morone@noaa.gov

Part II Technical Section

The NCEP Models

Currently, graphics from four of the NCEP's forecast models are available on this web site. These forecast models are:

1. The Eta

Link to the latest information about the Eta model:

http://www.emc.ncep.noaa.gov/modelinfo

The Eta model is a regional mesoscale model using enhanced terrain and improved parameterization of surface and precipitation processes. It produces forecasts out to 84 hours at 00 and 12Z and out to 48 hours at 06 and 18Z

2. The Aviation AVN

Link to the latest information about the AVN model:

http://www.emc.ncep.noaa.gov/modelinfo

The AVN model is a global spectral model used primarily for aviation weather forecasts. The AVN provides guidance out to 126 hours at 00 and 12Z and out to 84 hours at 06 and 18Z

3. The Medium Range Forecast (MRF)

Link to the latest information about the MRF model:

http://www.emc.ncep.noaa.gov/modelinfo

The MRF is a medium range global forecast model. It is the same global spectral model as the AVN, but produces forecasts out to 16 days (384 hours) once per day at 00Z.

4. The Nested Grid model (NGM)

Link to the latest information about the NGM model:

http://www.emc.ncep.noaa.gov/modelinfo

The NGM produces regional forecasts out to 48 hours at 00 and 12Z only. Its name comes from the technique of using a finer grid over North America and coarser grid over the oceans.

The Basic Set of Graphics

A basic set of seven graphics of the North American area are produced for each model at each forecast hour. These seven graphics are:

1. 250 mb heights and winds

2. 300 mb heights and winds

3. 500 mb heights, vorticity and winds

4. 700 mb heights, relative humidity and omega

5. 850 mb heights, temperatures and winds

6. 6-hour total precipitation, mean sea level pressure and 850 mb heights

7. Mean sea level pressure, 1000-500 thickness and 6-hour precipitation.

The graphics are depicted in three different resolutions to accommodate various display and download capabilities. These resolutions are

1. Coarse 640x480 image size, approximately 37 kilobytes per image

2. Medium 1024x768 image size, approximately 70 kilobytes per image

3. Fine 1280x1024 image size, approximately 100 kilobytes per image

In addition, two series of four panel charts are available. The first of these display a chart at four consecutive forecast time steps. These time steps are either the 00 through 18 hour forecasts or the 24 hours through 42 hours forecasts.

The second series of four panel displays are four related graphics at the same forecast hour. These are:

1. 500 mb, mean sea level, 700 mb, and 850 mb

2. 300 mb, 850 mb, 700 mb, and mean sea level pressure

These graphics are depicted in only the coarse resolution.

NCEP is planning to add two new domains using this same basic set of graphics at each model forecast time step. The first domain covers the North Pacific area from Guam and Hawaii to Northern Alaska. The second new domains covers the Caribbean Sea, the Gulf of Mexico, and out into the North Atlantic Ocean for the Eta model. For the AVN model, the area of coverage is expanded to include much of the tropical North Atlantic Ocean to North Western Africa.

NCEP is also planning to add a new set of total accumulated precipitation graphics over the North American domain. These will be in addition to those graphics currently being made for the 6 hour total accumulated precipitation. The new graphics will display total accumulated precipitation for 12 hours, 24 hours, 36 hours, 48 hours, and 60 hours at each model forecast period.

The processing that creates these forecast graphics uses the NAWIPS software,This software is used to convert forecast model output into GIF images to be transferred to the internet website. The NAWIPS software is executed on a single processor on the IBM SP supercomputer running in parallel with the various forecast models. This configuration allows for graphics from early forecast hours to be available on the internet before a model has completed.

The NAWIPS software on the IBM SP is the same version as that used at all the national centers.

All HTML documents are produced in real time on the NCEP's supercomputer as the models complete each forecast hour.

Future Enhancements

Two new backgrounds are planned: 1) The North Pacific area covering Guam, Hawaii and Alaska, and 2) the Caribbean area. Additional total precipitation graphics are planned to cover periods longer than 6 hours. Finally, forecast graphics from additional models run at NCEP will be added including those from the Rapid Update Cycle and the Wave Watch III. .

Future changes in the models, both additions and deletions, will be reflected at this website.