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By exchanging angular momentum with the solid portion of the earth, the atmosphere plays a vital role in exciting small but measurable changes in the rotation of our planet. Recognizing this relationship, the International Earth Rotation Service invited the U.S. National Meteorological Center to organize a Sub-bureau for Atmospheric Angular Momentum (SBAAM) for the purpose of collecting, distributing, archiving, and analyzing atmospheric parameters relevant to earth rotation/polar motion. These functions of wind and surface pressure are being computed with data from several of the world's weather services, and they are being widely applied to the research and operations of the geodetic community. The SBAAM began operating formally in October 1989, and this article highlights its development, operations, and significance.

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A new data product calculates snowfall rates from weather data beamed directly from several satellites, helping meteorologists provide fast, accurate weather reports and forecasts.

Analyses and forecasts for the first 2 weeks of the Genesis of Atlantic Lows Experiment (GALE) are described. These fields were produced using the National Meteorological Center (NMC) Regional Analysis and Forecast System (RAFS). Two sets of analyses and forecasts were constructed: one using the NMC operational database only (Level Ilia), and one using the NMC data merged with high-density observations taken during GALE (Level 1Mb). During the first 14 days of GALE, supplemental data were collected throughout two Intensive Observing Periods (lOPs). Comparisons of the Level Ilia and lllb analyses over the GALE observing region in the southeastern United States indicated a worsening of the geopotential height analysis at operational NWS rawinsonde sites using the supplemental lllb data. This was caused by inconsistencies in the height measurements at the high-density GALE rawinsonde sites. Such patterns were not observed in the wind and temperature analyses. During IOP No. 1, the Level Ilia and lllb Nested Grid Model (NGM) forecasts were nearly identical. For IOP No. 2, one forecast cycle saw an improvement in the Level lllb forecasts due to offshore GALE dropwindsonde data, while another was improved by the inclusion of late-arriving rawinsonde data in the lllb analysis. The inland, high-density GALE soundings, however, had a negligible impact on NGM forecasts during the entire 12-day period.