Local on the 7's or Local Forecast is the portion of programming where viewers see current weather conditions & local weather forecasts for their respective area on The WeatherCenter in the United States. The name comes from the timing of the segment, as the times it airs end in "7" (such as 9:17, 9:27, etc.) & because of the timing of the segment, "Local on the 7's" airs in 10-minute intervals.
Before the implementation took place in mid of 1995, the forecast was seen either every 5 minutes or 8 times an hour @ various times (more in the morning & less @ night). The name was introduced on April 21st, 1996 to coincide with a sweeping revamp of the channel's presentation. The WeatherCenter filed for a trademark on the name on June 24th, 1997.
Forecasts are generated by a WC-Star machine. The machines are installed in a headend & receive the information from the vertical blanking interval of the TWC video feed & from data transmitted on satellite. The information is then inserted over the TWC feed with local insertion technologies
As of 2008, the majority of cable operators use the WC-WX-Star, the latest Star system. The WC-WX-Star platform can also generate graphics for WeatherCenter 24/7, The WeatherCenter's 24-hour localized weather network. With an WC-WX-Star, cable viewers see current weather conditions for their area, surrounding areas & their region. 36-hour, daypart & 7-day forecasts, almanacs, air quality & health reports, specialized school day & activity forecasts, for coastal areas: tides & marine forecasts & in certain large media markets, traffic conditions supplied by Traffic Pulse (which gathers the information in real time from intelligent transportation systems operated by state departments of transportation).
The WC-WX-Star is not the only type of Star in operation. 3 other Star systems are used sporadically. WC-Star 4000 is the oldest & the first in the series that produces graphical local forecasts & radar. WC-Star Jr. is a budget model introduced in 1993 that was very uncommon from it's introduction. It's similar to the now-discontinued WC-Star III in terms of products & appearance, but uses the typeface of the 4000.
WC-Star XL, introduced in the fall of 1998, is an IRIX-based machine, a major leap from 4000's in terms of capabilities & graphic generation. It was used for WeatherCenter 24/7 until 2003 (the first use of the WC-WX-Star was on WeatherCenter 24/7 that year).
As satellite TV is broadcast to a large area, this localized weather model must be adapted for it's viewers. The satellite forecast segment includes hourly forecasts for 20 major cities, 3-day forecasts for 40 U.S. cities, satellite loops & composite radars of the Northeast, the Southeast, the Midwest, the Northwest & the Southwest, respectively. At :18 & :48 after the hour, the Northwest & the Southwest satellite/radars are replaced by 1 showing the entire West. WC-WX-Stars are hooked up @ both DirecTV's & DISH Network's primary uplink sites, but they run a different lower display line graphic @ all times even during TV commercial's. This cycles through current conditions (sky & temperature only) & today or next-day forecasts for major U.S. cities, as well as major airport delays. As of November 8th 2006, DISH Network viewers are now able to view local weather conditions & radar on The WeatherCenter on DISH Home Ch. 100, based on their billing ZIP code, along with access to weather in other cities. DirecTV viewers can get local forecasts by zip code, which works through the "interactive" function of later receiver models.
It's noted that during The WeatherCenter's "Storm Alert" mode (introduced 2005), specifically when a dangerous hurricane prepares to make landfall, the number of local forecasts seen throughout the hour is reduced from 6 times to 4 @ :18, :28, :48 & :58 past each hour
Lower Display Line (LDL)Edit
WC-Star systems also utilize weather information in the form of an Lower Display Line (LDL), the LDL displayed by WC-Star systems from Weather Star Jr. & earlier were text-based only & included only current conditions & monthly precipitation. WC-Star XL included a translucent background for the LDL & added weather forecasts, while the WC-WX-Star system includes current conditions & forecasts for 3 nearby areas & until March 11th 2010, included air quality indexes, travel forecasts for 3 cities in the region, traffic information & almanac data.
Time data was included on LDL's since the initial WC-Star system (though was dropped on March 11th, 2010 on the WC-WX-Star) & the current date was also included on systems from WC-Star XL & earlier. With the addition of a national LDL during national programming on March 11th 2010, cable headends still using the WC-Star 4000 & WC-Star Jr. will now overlay the text-only LDL over the national LDL as the 4000 & Jr.'s LDL's have no background (the LDL's on the 4000 & Jr. & earlier WC-Star systems contain no background for the LDL). The XL's LDL no longer gets a signal to cue either after this update. However, on extreme rare conditions, the 4000 &/or Jr.'s LDL's will cue & remain on for a period during the day it gets cued