Search Results

You are looking at 1 - 10 of 646 items for :

  • Weather and Forecasting x
  • Refine by Access: All Content x
Clear All
Roman Krzysztofowicz, William J. Drzal, Theresa Rossi Drake, James C. Weyman, and Louis A. Giordano

424 WEATHER AND FORECASTING -OLUME8Probabilistic Quantitative Precipitation Forecasts for River Basins ROMAN KRZYSZTOFOWICZDepartment of Systems Engineering, University of Virginia, Charlottesville, VirginiaWILLIAM J. DRZAL, THERESA ROSSI DRAKE, JAMES C. WEYMAN, AND LOUIS A. GIORDANONational Weather Service, Forecast Office, Pittsburgh. Pennsylvania(Manuscript received 22

Full access
David A. Lavers, N. Bruce Ingleby, Aneesh C. Subramanian, David S. Richardson, F. Martin Ralph, James D. Doyle, Carolyn A. Reynolds, Ryan D. Torn, Mark J. Rodwell, Vijay Tallapragada, and Florian Pappenberger

.g., Uttal et al. 2002 ), and cloud processes ( Flamant et al. 2018 ). In January and February 2018, there was an observational campaign called Atmospheric River Reconnaissance (AR Recon) in which research aircraft released dropsondes into atmospheric rivers (ARs; Ralph et al. 2018 ) and other dynamically active regions across the eastern North Pacific Ocean, along with radiosondes from sites in California. ARs are important because they are responsible for much of the water vapor flux across the

Open access
Zbyněk Sokol

1. Introduction Precipitation amount in a river basin is the principal input of hydrologic models. Precipitation inputs, calculated from observations and used in the models, can provide valuable hydrologic forecasts, but they are limited by a short lead time. For longer lead time, a quantitative precipitation forecast (QPF) is required. Numerical weather prediction (NWP) models are the basic tools of QPF. Despite significant progress in numerical modeling during the last decades, QPF is one of

Full access
Douglas K. Miller, David Hotz, Jessica Winton, and Lukas Stewart

1. Introduction and background The purpose of this study is to examine the influence of atmospheric rivers (ARs), narrow and elongated zones of rapid poleward-moving anomalously moist air at low levels originating from the subtropics and located just ahead of the surface cold front in midlatitude cyclones (e.g., Browning and Pardoe 1973 ; Newell et al. 1992 ; Zhu and Newell 1998 ), on precipitation events in the Pigeon River basin (PRB) as observed by a high-elevation rain gauge network

Full access
D.L. Fread, R.C. Shedd, G.F. Smith, R. Farnsworth, C.N. Hoffeditz, L.A. Wenzel, S.M. Wiele, J.A. Smith, and G.N. Day

SEPTEMBER 1995 FREAD ET AL. 477Modernization in the National Weather Service River and Flood ProgramD. L. FREAD,* R. C. SHEDD,* G. F. SMITH,* R. FARNSWORTH,* C. N. HOFFEDITZ,* L. A. WENZEL,* S. M. WIELE, ~: J. A. SMITH, @ AND G. N. DAY # *Ojfice of Hydrology, National Weather Service, Silver Spring, Maryland ~U

Full access
E. A. Stallings and L. A. Wenzel

VOL. 10, No. 3 WEATHER AND FORECASTING SEPTEMBER 1995Organization of the River and Flood Program in the National Weather Service E. A. STALLINGS AND L. A. WENZELOffice of Hydrology, National Weather Service, Silver Spring, Maryland(Manuscript received 17 March 1994, in final form 10 April 1995)ABSTRACT The National Weather Service is charged by law with the responsibility of issuing forecasts and

Full access
Thomas A. Andretta and Dean S. Hazen

demonstrated in northeast Colorado in the late 1980s ( Szoke and Wiesmueller 1989 ). The National Weather Service (NWS) deployment of Doppler weather radars (WSR-88D) throughout the intermountain west now provides operational forecasters an important tool for analyzing the mesoscale processes of winter storms. This study examines one convergence zone event that developed in the Snake River plain (SRP) of eastern Idaho and produced significant snowfall over a relatively small geographical area in November

Full access
L.W. Larson, R.L. Ferral, E.T. Strem, A.J. Morin, B. Armstrong, T.R. Carroll, M.D. Hudlow, L.A. Wenzel, G.L. Schaefer, and D.E. Johnson

SEPTEMBER 1995 LARSON ET AL. 465Operational Responsibilities of the National Weather Service River and Flood Program L. W. LARSON Central Region Regional Hydrologist OJ~ce, National Weather Service, Kansas City, Missouri R. L. FERRAL, E. T. STREM, AND A. J. MORIN California-Nevada River Forecast Center, National Weather Service, Sacramento, California

Full access
Qi Mao, Stephen F. Mueller, and Hann-Ming Henry Juang

1. Introduction The Tennessee River is the fifth largest river in the United States. Located in the southeastern United States, its drainage basin covers almost 106 000 km 2 and includes nearly 68 000 km of rivers and streams. An average of nearly 1.15 × 10 8 L min −1 of water flows through the river near its confluence with the Ohio River in western Kentucky. The Tennessee Valley Authority (TVA)—an agency of the U.S. federal government—was created to control flooding on the river and its

Full access
Laurel L. DeHaan, Andrew C. Martin, Rachel R. Weihs, Luca Delle Monache, and F. Martin Ralph

1. Introduction Atmospheric rivers (ARs), or narrow bands of abnormally large water vapor transport, are increasingly recognized for their significance in water supply and flooding in many regions around the globe. Along the U.S. West Coast ARs can produce 20%–50% of annual precipitation ( Gershunov et al. 2017 ; Dettinger et al. 2011 ). Precipitation from ARs can have either beneficial or harmful consequences: lower intensity ARs can replenish the water supply and relieve drought conditions

Restricted access