WAAS, that set of wonderful satellites that greatly improves our GPS accuracy, will be experiencing some changes. For the next two months (until the beginning of April 2006), the company that owns one of the WAAS satellites will be moving it westward. From the article:
WANDERING WAAS: SATELLITE TO RELOCATE One of the geostationary satellites carrying the FAA's Wide Area Augmentation System (WAAS) signal won't be so stationary during the next 60 days. Satellite owner Inmarsat will be repositioning and re-aiming a satellite, shifting coverage to the west. The move will have no effect on the vast majority of GPS users. That's because most pilots use just the basic GPS signal, provided by the U.S. military. "But there may be times during the next two months when WAAS won't be available for precision vertical guidance," said Randy Kenagy, AOPA director of advanced technology. "That means you should check notams to make sure that LPV (lateral precision with vertical guidance) approach will be available when you want it." See AOPA Online.
Basically, this means that the vertical accuracy may not be stellar for the next two months. After that, my guess is we'll have better WAAS coverage here in the Wild Wild West (but that's just my speculation).