Accession Number : ADB115170

Title :   AFGWC (Air Force Global Weather Central) Cloud Forecast Models

Descriptive Note : Technical note

Corporate Author : AIR FORCE GLOBAL WEATHER CENTRAL OFFUTT AFB NE

Personal Author(s) : Crum, Timothy D

PDF Url : ADB115170

Report Date : Apr 1987

Pagination or Media Count : 79

Abstract : AFGWC has three cloud forecast models: Five-Layer (5LAYER), High Resolution Cloud Prognosis (HRCP), and Tropical Cloud Forecasting Model (TRONEW) . These models satisfy a wide range of requirements and have been in operation since the early 1970s. The 5LAYER model makes extra-tropical forecasts for periods up to 48 hours. Forecasts of layer and total cloud, cloud type, layer temperatures, and icing and weather conditions are made. The 5LAYER model uses a quasi-Lagrangian approach to make these forecasts. The trajectories needed for these forecasts are computed from the AWS Global Spectral Model (GSM) derived wind forecasts. The 5LAYER moisture is initialized from the Real-Time Nephanalysis Model (RTNEPH) layer cloud-amount and the Multi-layer Analysis Model (MULTAN) layer dew-point depression. The 5LAYER temperatures are initialized from the High Resolution Analysis System (HIRAS) and GSM derived temperatures. The High Resolution Cloud Prognosis (HRCP) model combines RTNEPH analyzed cloud input with 5LAYER trajectories to produce high resolution (25 nm) , short-range (out to 9 hour) cloud forecasts. The TRONEW model uses the analyzed RTNEPH cloud to make 24 hour persistence cloud forecasts for the tropics.

Descriptors :   *CLOUDS, *WEATHER FORECASTING, AIR FORCE OPERATIONS, COMPUTERIZED SIMULATION, FORECASTING, GLOBAL, HIGH RESOLUTION, INPUT, LAYERS, MATHEMATICAL MODELS, MODELS, PREDICTIONS, RANGE(EXTREMES), REQUIREMENTS, SPECTRA, TEMPERATURE, TRAJECTORIES, TROPICAL REGIONS, WEATHER

Subject Categories : Meteorology

Distribution Statement : APPROVED FOR PUBLIC RELEASE