Search Results

You are looking at 71 - 80 of 19,080 items for :

  • Forecasting techniques x
  • All content x
Clear All
Tom H. Durrant, Diana J. M. Greenslade, Ian Simmonds, and Frank Woodcock

these changes is desired. One such technique is the operational consensus forecast (OCF) scheme of Woodcock and Engel (2005) . In its complete form, OCF combines forecasts derived from a multimodel ensemble to produce an improved real-time forecast at locations where recent observations are available. Component model biases and weighting factors are derived from a training period of previous model forecasts and verifying observations. The next real-time OCF forecast is a weighted average of the set

Full access
Gary P. Ellrod and David I. Knapp

150 WEATHER AND FORECASTING VOLUME7FORECASTING TECHNIQUESAn Objective Clear-Air Turbulence Forecasting Technique: Verification and Operational Use GARY P. ELLRODSatellite Applications Laboratory (NOAA/NESDIS), Washington, D.C. DAVID I. KNAPPAir Force Global Weather Central (AFGWC), Offutt Air Force Base, Nebraska6 June 1991 and 12 September 1991 An objective technique for forecasting clear

Full access
Domingo Muñoz-Esparza and Robert Sharman

, and low-level turbulence (LLT) owing to turbulence events within the atmospheric boundary layer. These turbulence forecasting techniques typically relate the large-scale atmospheric turbulence production mechanisms that are explicitly resolved with horizontal grid spacings of NWP models (~10 km) to aircraft-scale turbulence (~10–100 m), through the assumption of a downscale energy-cascade process (e.g., Lindborg 1999 ). An example of turbulence forecasting algorithm is the Graphical Turbulence

Open access
Adrienne Tivy, Bea Alt, Stephen Howell, Katherine Wilson, and John Yackel

coincident El Niño and positive North Atlantic Oscillation (NAO) episodes. The goal of this study is to improve seasonal or long-range (3-month lead) forecasts for the spring opening of the shipping route through Hudson Bay. A predictive model is developed using multiple linear regression techniques. More than 1500 time series representing dominant modes in Northern Hemisphere atmospheric and oceanic variability, local climate, and sea ice conditions are tested as potential predictors and are described

Full access
TAKASHI NITTA and JOHN B. HOVERMALE

652MONTHLY WEATHER REVIEW Vol. 97, No. 9UDC 551.509.313A TECHNIQUE OF OBJECTIVE ANALYSIS AND INITIALIZATION FOR THE PRIMITIVE FORECAST EQUATIONS TAKASHI NlTTA and JOHN B. HOVERMALE *National Meteorological Center, Weather Bureau, ESSA, Washington D.C.AB!7RACTA technique .of initialization for the primitive forecast equations is presented. The method consists of a march-ing prediction scheme performed in such a manner that the large-scale solution remains approximately steady

Full access
Yulia R. Gel

application of the discussed approaches to the bias correction of 48-h MM5 forecasts of surface temperature in the Pacific Northwest. The proposed methods are compared with each other and the grid-based “obs-based” method of Wedam et al. (2005) in terms of mean absolute error (MAE). In addition, section 3 reports the results on the “improve to hurt” statistics of the proposed techniques, that is, the number of cases when the bias has been removed or added at a site of interest. The paper concludes

Full access
Le Bao, Tilmann Gneiting, Eric P. Grimit, Peter Guttorp, and Adrian E. Raftery

1. Introduction Forecasts of wind direction have varied and important uses, ranging from air pollution management to aircraft and ship routing and recreational boating. However, wind direction is an angular variable that takes values on the circle, as opposed to other weather quantities, such as temperature, quantitative precipitation, or wind speed, which are linear variables that take values on the real line. As a result, traditional postprocessing techniques for forecasts from numerical

Full access
John F. Henz

1284 JOURNAl, OF APPI, IED METEOROLOGY Vo~.uM~,llAn Operational Technique of Forecasting Thunderstorms Along the Lee Slopes of a Mountain Range JoH~ F. HEsz Dept. of Atmospheric Science, Colorado State University, Fort Collins 80521 (Manuscript received 19 May 1972, in revised form 3 Au~st 1972) ABSTRACT The lee slopes of the Rocky Mouut~ius from Montana

Full access
Seoyeon Lee and Kwang-Yul Kim

Stone P. , 1988 : Global climate changes as forecast by Goddard Institute for Space Studies three-dimensional model . J. Geophys. Res. , 93 , 9341 – 9364 , doi: 10.1029/JD093iD08p09341 . Hewitson, B. C. , and Crane R. G. , 1996 : Climate downscaling: Techniques and application . Climate Res. , 7 , 85 – 95 , doi: 10.3354/cr007085 . Hoskins, B. J. , 2013 : The potential for skill across the range of the seamless weather-climate prediction problem: A stimulus for our science . Quart

Full access
W. E. Baker, R. Atlas, M. Halem, and J. Susskind

1544 MONTHLY WEATHER REVIEW VOLUME 112A Case Study of Forecast Sensitivity to Data and Data Analysis Techniques W. E. BAKER, R. ATLAS, M. HALEM AND J. SUSSKINDLaboratory for Atmospheric Sciences, NASA-Goddard $lmce Flight Center, Greenbelt, MD 20771(lvlanuscript received 5 July 1983, in final form 30 March 1984)ABSTRACT In this study we examine the sensitivity of forecast skill to

Full access