Development of the National Digital Forecast Database Web Display Presented by: Marc Saccucci NOAA/NWS/Meteorological Development Laboratory NOAA WebShop 2004

> Introduction The National Digital Forecast The National Digital Forecast Database (NDFD) is a mosaic of official Weather Forecast Office (WFO) forecasts The NDFD became a new experimental public resource on the web in 2003 The NDFD became a new experimental public resource on the web in 2003 Allows users and partners to create a wide range of text, graphic, and image products Allows users and partners to create a wide range of text, graphic, and image products

Example NDFD National Forecast Graphic

> NDFD Web Presence Goal to make graphic and data rich page accessible (Section 508 Compliant) Goal to make graphic and data rich page accessible (Section 508 Compliant) Challenging due to graphical nature of product and quantity of data to display Challenging due to graphical nature of product and quantity of data to display

> Scope of NDFD Data Approximately 15,000 forecast images updated hourly Approximately 15,000 forecast images updated hourly 5 km data resolution 5 km data resolution Many predefined zooms (national, sectors, states) Many predefined zooms (national, sectors, states) Currently includes 9 forecast elements out to 7 days Currently includes 9 forecast elements out to 7 days Example NDFD Forecast Image

> NDFD Predefined Regions 16 Sectors 16 Sectors CONUS CONUS Every state Every state Puerto Rico Puerto Rico Coming soon: Coming soon: –Alaska –Hawaii –Guam

Part of the Rehabilitation Act of 1973, amended in 1998 to include latest information technology Part of the Rehabilitation Act of 1973, amended in 1998 to include latest information technology Created the requirement that Federal Agencies provide electronic information technology accessible to individuals with disabilities Created the requirement that Federal Agencies provide electronic information technology accessible to individuals with disabilities Alternate methods of retrieving information should be made available unless it causes “undue burden” Alternate methods of retrieving information should be made available unless it causes “undue burden” -source: -source: > Section 508 Accessibility Overview

> Accessibility Considerations Visual Visual –Colorblindness –Blindness Mobility Mobility Cognitive Cognitive Equipment Equipment Software Software

> Accessibility Considerations: Visual Colorblindness Colorblindness –Perform color recognition tests –Modify color curves to eliminate problems where possible –When colors cannot be modified to perfectly distinguish colors try: Contrast Contrast Context Context

> Accessibility Considerations: Visual Deuteranopia Colorblindness Test (green) Deuteranopia Colorblindness Test (green) Image produced by:

> Accessibility Considerations: Visual Protanopia Colorblindness Test (red) Protanopia Colorblindness Test (red) Image produced by:

> Accessibility Considerations: Visual Tritanopia Colorblindness Test (blue/yellow) Tritanopia Colorblindness Test (blue/yellow) Image produced by:

> Accessibility Considerations: Visual Blindness Blindness –Make pages accessible to screen readers “ALT” tags on all images “ALT” tags on all images Check for navigation ease Check for navigation ease Consistent page navigation Consistent page navigation Web page bookmarks to skip top navigation (enter key) Web page bookmarks to skip top navigation (enter key) Provide alternate methods of getting information Provide alternate methods of getting information

> Accessibility Considerations: Visual Dynamic Images Dynamic Images –Problem: “ALT” tags could not describe dynamic data –NDFD Solutions: Probe the data to obtain forecast information Probe the data to obtain forecast information Pop up alternate text representation of select point forecasts inline Pop up alternate text representation of select point forecasts inline Include alternate “City Forecasts” in plain HTML Include alternate “City Forecasts” in plain HTML

> Accessibility Considerations: Mobility Mobility Impairment Considerations Mobility Impairment Considerations –Similar to blindness considerations for screen readers –Do not assume mouse use –Test key page navigation –Utilize consistent page navigation –Web page bookmarks to skip top navigation (enter key) –Provide alternate methods of getting information

> Accessibility Considerations: Cognitive Try to reduce the volume of information Try to reduce the volume of information Supply multiple methods of viewing data Supply multiple methods of viewing data –Users can choose a method that best suits their needs Simplify/summarize data where possible Simplify/summarize data where possible

> Accessibility Considerations: Cognitive The NDFD Solution: The NDFD Solution: –Split the forecast data into 12 hr periods. (Daily View) –Split the forecast data into element groupings (Weekly View) –Provided rollover forecast box at select cities

> Accessibility Considerations: Equipment Connection Speeds Connection Speeds –Download speeds are important –Limit image file size –Provide navigation that allows users to jump to choice page Screen Size Screen Size –Assume users only have 800X600 resolution

> Accessibility Considerations: Software Avoid use of applets and plugins Avoid use of applets and plugins Sparingly use PDF format Sparingly use PDF format Test pages with multiple browsers Test pages with multiple browsers Considerations before using various software: Considerations before using various software: –Use if document formatting must be perfectly maintained –Will slow user navigation down –Can impact accessibility –Will users be irritated/burdened by downloading software to view document?

> NDFD Web: Future Improvements Forecasts at every point (Latitude/Longitude, zip code, street address, etc) Forecasts at every point (Latitude/Longitude, zip code, street address, etc) –Significantly improves accessibility to data Can provide data in: Can provide data in: –Daily summaries –Meteograms –Worded forecasts –XML Now available at Now available at

For More Information: NDFD Graphical Forecast Page: NDFD Information Page: NDFD XML Web Service: Personal /Phone: x107