DOCSLIB.ORG

Atlantic Hurricane Database Uncertainty and Presentation of a New Database Format

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

3576 MONTHLY WEATHER REVIEW VOLUME 141 Atlantic Hurricane Database Uncertainty and Presentation of a New Database Format CHRISTOPHER W. LANDSEA AND JAMES L. FRANKLIN NOAA/NWS/NCEP/National Hurricane Center, Miami, Florida (Manuscript received 4 September 2012, in final form 31 December 2012) ABSTRACT ‘‘Best tracks’’ are National Hurricane Center (NHC) poststorm analyses of the intensity, central pressure, position, and size of Atlantic and eastern North Pacific basin tropical and subtropical cyclones. This paper estimates the uncertainty (average error) for Atlantic basin best track parameters through a survey of the NHC Hurricane Specialists who maintain and update the Atlantic hurricane database. A comparison is then made with a survey conducted over a decade ago to qualitatively assess changes in the uncertainties. Finally, the implications of the uncertainty estimates for NHC analysis and forecast products as well as for the pre- diction goals of the Hurricane Forecast Improvement Program are discussed. 1. Introduction and compares the survey results to independently de- rived estimates from Torn and Snyder (2012). A similar ‘‘Best tracks’’ are National Hurricane Center (NHC) survey conducted in 1999 provides some insight into poststorm analyses of the intensity, central pressure, changes in dataset quality during the last decade. Fi- position, and size of tropical and subtropical cyclones nally, we discuss implications of the uncertainty esti- (Jarvinen et al. 1984), and represent the official histori- mates for NHC analysis/forecast products, as well as cal record for each storm. These analyses (apart from for the predictability goals of the Hurricane Forecast those for size) make up the database known as the hur- Improvement Program (Gall et al. 2013). ricane database (HURDAT) and have been used for a wide variety of applications: verification of official and model predictions of track and intensity (McAdie 2. Best tracks—Definition, content, and procedures and Lawrence 2000), development of intensity fore- The NHC develops best tracks for intensity,1 central casting techniques (DeMaria 2009), seasonal forecasting pressure, position, and size2 with a precision of 5 kt (Klotzbach 2007), setting of appropriate building codes 2 (1kt 5 0.5144 m s 1), 1 mb, 0.18 latitude/longitude [;6nmi for coastal zones (American Society of Civil Engineers (1 n mi 5 1.852 km)], 5 n mi, 5 n mi, and 5 n mi, respec- 1999), risk assessment for emergency managers (Jarrell tively. Best track intensity and position estimates have et al. 1992), analysis of potential losses for insurance and been provided for every synoptic time (0000, 0600, 1200, business interests (Malmquist and Michaels 2000), and and 1800 UTC) for all tropical storms, hurricanes, and climatic change studies (Knutson et al. 2010). subtropical storms since 1956 (Jarvinen et al. 1984). Prior Given the widespread use of HURDAT for meteo- to 1956, best track information was analyzed only once rological, engineering, and financial decision making, it or twice a day; interpolation was used to obtain best- is surprising that very little has been published regard- track estimates for the remaining synoptic times when ing the uncertainties inherent in the database; Torn the HURDAT database was constructed in the early and Snyder (2012) is a notable exception. This current 1980s (Jarvinen et al. 1984). work estimates the uncertainties through a survey of the best track authors, the NHC Hurricane Specialists, 1 Maximum 1-min-average wind associated with the tropical cyclone at an elevation of 10 m with an unobstructed exposure Corresponding author address: Christopher W. Landsea, NOAA/ (Office of the Federal Coordinator for Meteorological Services and NWS/NCEP/National Hurricane Center, 11691 SW 17th St., Miami, Supporting Research 2012). FL 33165. 2 Cyclone size is described by the maximum extent of winds of 34, E-mail: [email protected] 50, and 64 kt in each of four quadrants about the center. DOI: 10.1175/MWR-D-12-00254.1 Unauthenticated | Downloaded 10/02/21 12:54 AM UTC OCTOBER 2013 L A N D S E A A N D F R A N K L I N 3577 Originally, central pressure best track values were discrepancies between the actual (and well known) only included into HURDAT if there was a specific locations of a tropical cyclone and its corresponding observation that could be used explicitly as the best best track value. The smoothing places greater weight track value. Beginning in 1979, central pressures have to data for which confidence is relatively high (e.g., day- been estimated for every synoptic time. Size informa- light positions are considered more reliable than night- tion has been included in the best track data since 2004. time positions). An exception to this smoothing paradigm Finally, asynpotic points (primarily to denote times of is made for landfall. Because landfall is defined as the landfall as well as peak intensities that occurred at times intersection of the tropical cyclone center and the coast- other than the synoptic hours) have been incorporated line, these points cannot logically be smoothed in time into the best tracks for the years 1851–1945 and 1991 or space; landfall data in the HURDAT2 therefore onward. Because the HURDAT format could not ac- represent NHC’s best estimates of the precise location, commodate either the size of the data or asynoptic re- intensity, and timing of landfall. cords, a new format, the second-generation hurricane At the conclusion of each storm, one of the NHC database (HURDAT2), has been developed (see the Hurricane Specialists is assigned to conduct the post- appendix). storm analysis on a rotating basis. The specialist creates A best track is defined as a subjectively smoothed a draft best track, which is reviewed at NHC by the other representation of a tropical cyclone’s history over its specialists, the Hurricane Specialists Unit (HSU) branch lifetime, based on a poststorm assessment of all avail- chief, the science and operations officer, the deputy di- able data. It is important to recognize that the best rector, and the director. The review process ensures track is not simply a reissuance of the operational values. a measure of continuity across the various best track Many types of meteorological data arrive with some la- authors. tency [e.g., microwave imagery, scatterometer data, and Advanced Microwave Sounding Unit (AMSU) data], and some data do not become available until well after 3. Observations available for best track a storm is over. Furthermore, knowing what happened assessments subsequent to a given point in time can be instrumental a. Intensity in the correct assessment of what was occurring at that point in time. NHC Hurricane Specialists review the One would expect that the quality of the best tracks entire track with all the available information and put would vary depending on the amount and reliability of together, from often contradictory data, a history that observations that are available for the poststorm as- makes sense with respect to known tropical cyclone sessments. Figure 1 illustrates how the available data can dynamics.3 vary from cyclone to cyclone. Hurricane Gordon in 2006 Because the best tracks are subjectively smoothed, was a cyclone almost exclusively monitored remotely they will not precisely recreate a storm’s history, even by satellite measurements (Blake 2006), with the ma- when that history is known to great accuracy. Aliasing jority of data provided by the Satellite Analysis Branch considerations suggest that variations with periods shorter (SAB) and Tropical Analysis and Forecast Branch than about 24 h (4 times the 6-h resolution of the best (TAFB) Dvorak analyses (Dvorak 1975, 1984). In ad- tracks) cannot be represented by HURDAT. So as the dition, observations available in recent years for tropical best tracks are constructed, apparent variations, whether cyclones well away from land include the Advanced in intensity, central pressure, location, or size, with pe- Dvorak Technique (ADT; Olander and Velden 2007), riods shorter than 24 h are typically not captured. This AMSU (Brueske and Velden 2003; Demuth et al. 2006), helps ensure that the best track values are represen- and scatterometer data from the Quick Scatterometer tative of the 6-h interval surrounding the best track (QuikSCAT) and Advanced Scatterometer (ASCAT) time. On the other hand, the smoothing (particularly satellites (Brennan et al. 2009). with track) means that there will routinely be small Hurricane Dean had much more aircraft reconnaiss- ance data available for most of its lifetime. Aircraft re- connaissance missions (Franklin 2008), from both the 3 There are some objective methodologies available for weight- U.S. Air Force Reserve’s 53rd Weather Reconnaissance ing various observations to assist in providing best tracks. (e.g., the Squadron C-130s and the National Oceanic and Atmo- Automated Tropical Cyclone Forecast system; Sampson and spheric Administration (NOAA) Aircraft Operations Schrader 2000). The current procedure at NHC is for the NHC Hurricane Specialists to use their knowledge and experience to Center Orion P-3s, provide flight-level winds that can subjectively weight the various observations available and de- be adjusted to the surface (Franklin et al. 2003), termine the best tracks manually. Stepped Frequency Microwave Radiometer (SFMR) Unauthenticated | Downloaded 10/02/21 12:54 AM UTC 3578 MONTHLY WEATHER REVIEW VOLUME 141 FIG. 1. Examples of tropical cyclone best track intensities based upon (a) mainly satellite data and (b) upon a mixture of satellite and aircraft reconnaissance data. The figures indicate the best track intensities as the green line with blue symbols indicating Dvorak classifications, red symbols indicating aircraft reconnaissance observations, purple symbols indicating NASA QuikSCAT measurements, and gold symbols indicating dropsonde observations. winds (Uhlhorn et al. 2007), and global positioning system many of the data plotted for Dean will not be represen- (GPS) dropwindsonde winds (Franklin et al. 2003). tative of the cyclone’s intensity (e.g., flight-level-adjusted Figure 1 gives the appearance of less spread in the winds from the left-rear quadrant of the cyclone).
Recommended publications
  • Subtropical Storms in the South Atlantic Basin and Their Correlation with Australian East-Coast Cyclones

    Subtropical Storms in the South Atlantic Basin and Their Correlation with Australian East-Coast Cyclones

    2B.5 SUBTROPICAL STORMS IN THE SOUTH ATLANTIC BASIN AND THEIR CORRELATION WITH AUSTRALIAN EAST-COAST CYCLONES Aviva J. Braun* The Pennsylvania State University, University Park, Pennsylvania 1. INTRODUCTION With the exception of warmer SST in the Tasman Sea region (0°−60°S, 25°E−170°W), the climate associated with South Atlantic ST In March 2004, a subtropical storm formed off is very similar to that associated with the coast of Brazil leading to the formation of Australian east-coast cyclones (ECC). A Hurricane Catarina. This was the first coastal mountain range lies along the east documented hurricane to ever occur in the coast of each continent: the Great Dividing South Atlantic basin. It is also the storm that Range in Australia (Fig. 1) and the Serra da has made us reconsider why tropical storms Mantiqueira in the Brazilian Highlands (Fig. 2). (TS) have never been observed in this basin The East Australia Current transports warm, although they regularly form in every other tropical water poleward in the Tasman Sea tropical ocean basin. In fact, every other basin predominantly through transient warm eddies in the world regularly sees tropical storms (Holland et al. 1987), providing a zonal except the South Atlantic. So why is the South temperature gradient important to creating a Atlantic so different? The latitudes in which TS baroclinic environment essential for ST would normally form is subject to 850-200 hPa formation. climatological shears that are far too strong for pure tropical storms (Pezza and Simmonds 2. METHODOLOGY 2006). However, subtropical storms (ST), as defined by Guishard (2006), can form in such a.
  • Downloaded 09/24/21 04:27 PM UTC 1512 MONTHLY WEATHER REVIEW VOLUME 146

    Downloaded 09/24/21 04:27 PM UTC 1512 MONTHLY WEATHER REVIEW VOLUME 146

    MAY 2018 C A V I C C H I A E T A L . 1511 Energetics and Dynamics of Subtropical Australian East Coast Cyclones: Two Contrasting Cases LEONE CAVICCHIA School of Earth Sciences, University of Melbourne, Melbourne, Australia ANDREW DOWDY Bureau of Meteorology, Melbourne, Australia KEVIN WALSH School of Earth Sciences, University of Melbourne, Melbourne, Australia (Manuscript received 27 October 2017, in final form 13 March 2018) ABSTRACT The subtropical east coast region of Australia is characterized by the frequent occurrence of low pressure systems, known as east coast lows (ECLs). The more intense ECLs can cause severe damage and disruptions to this region. While the term ‘‘east coast low’’ refers to a broad classification of events, it has been argued that different ECLs can have substantial differences in their nature, being dominated by baroclinic and barotropic processes in different degrees. Here we reexamine two well-known historical ECL case studies under this perspective: the Duck storm of March 2001 and the Pasha Bulker storm of June 2007. Exploiting the cyclone phase space analysis to study the storms’ full three-dimensional structure, we show that one storm has features similar to a typical extratropical frontal cyclone, while the other has hybrid tropical–extratropical charac- teristics. Furthermore, we examine the energetics of the atmosphere in a limited area including both systems for the ECL occurrence times, and show that the two cyclones are associated with different signatures in the energy conversion terms. We argue that the systematic use of the phase space and energetics diagnostics can form the basis for a physically based classification of ECLs, which is important to advance the understanding of ECL risk in a changing climate.
  • ANNUAL SUMMARY Atlantic Hurricane Season of 2005

    ANNUAL SUMMARY Atlantic Hurricane Season of 2005

    MARCH 2008 ANNUAL SUMMARY 1109 ANNUAL SUMMARY Atlantic Hurricane Season of 2005 JOHN L. BEVEN II, LIXION A. AVILA,ERIC S. BLAKE,DANIEL P. BROWN,JAMES L. FRANKLIN, RICHARD D. KNABB,RICHARD J. PASCH,JAMIE R. RHOME, AND STACY R. STEWART Tropical Prediction Center, NOAA/NWS/National Hurricane Center, Miami, Florida (Manuscript received 2 November 2006, in final form 30 April 2007) ABSTRACT The 2005 Atlantic hurricane season was the most active of record. Twenty-eight storms occurred, includ- ing 27 tropical storms and one subtropical storm. Fifteen of the storms became hurricanes, and seven of these became major hurricanes. Additionally, there were two tropical depressions and one subtropical depression. Numerous records for single-season activity were set, including most storms, most hurricanes, and highest accumulated cyclone energy index. Five hurricanes and two tropical storms made landfall in the United States, including four major hurricanes. Eight other cyclones made landfall elsewhere in the basin, and five systems that did not make landfall nonetheless impacted land areas. The 2005 storms directly caused nearly 1700 deaths. This includes approximately 1500 in the United States from Hurricane Katrina— the deadliest U.S. hurricane since 1928. The storms also caused well over $100 billion in damages in the United States alone, making 2005 the costliest hurricane season of record. 1. Introduction intervals for all tropical and subtropical cyclones with intensities of 34 kt or greater; Bell et al. 2000), the 2005 By almost all standards of measure, the 2005 Atlantic season had a record value of about 256% of the long- hurricane season was the most active of record.
  • Thor's Legions American Meteorological Society Historical Monograph Series the History of Meteorology: to 1800, by H

    Thor's Legions American Meteorological Society Historical Monograph Series the History of Meteorology: to 1800, by H

    Thor's Legions American Meteorological Society Historical Monograph Series The History of Meteorology: to 1800, by H. Howard Frisinger (1977/1983) The Thermal Theory of Cyclones: A History of Meteorological Thought in the Nineteenth Century, by Gisela Kutzbach (1979) The History of American Weather (four volumes), by David M. Ludlum Early American Hurricanes - 1492-1870 (1963) Early American Tornadoes - 1586-1870 (1970) Early American Winters I - 1604-1820 (1966) Early American Winters II - 1821-1870 (1967) The Atmosphere - A Challenge: The Science of Jule Gregory Charney, edited by Richard S. Lindzen, Edward N. Lorenz, and George W Platzman (1990) Thor's Legions: Weather Support to the u.s. Air Force and Army - 1937-1987, by John F. Fuller (1990) Thor's Legions Weather Support to the U.S. Air Force and Army 1937-1987 John F. Fuller American Meteorological Society 45 Beacon Street Boston, Massachusetts 02108-3693 The views expressed in this book are those of the author and do not reflect the official policy or position of the Department of Defense or the United States Government. © Copyright 1990 by the American Meteorological Society. Permission to use figures, tables, and briefexcerpts from this monograph in scientific and educational works is hereby granted provided the source is acknowledged. All rights reserved. No part ofthis publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, elec­ tronic, mechanical, photocopying, recording, or otherwise, without the prior written permis­ sion ofthe publisher. ISBN 978-0-933876-88-0 ISBN 978-1-935704-14-0 (eBook) DOI 10.1007/978-1-935704-14-0 Softcover reprint of the hardcover 1st edition 1990 Library of Congress catalog card number 90-81187 Published by the American Meteorological Society, 45 Beacon Street, Boston, Massachusetts 02108-3693 Richard E.
  • Dr. Louis Uccellini Assistant Administrator for Weather Services and Director of the National Weather Service, National Oceanic and Atmospheric Administration, U.S

    Dr. Louis Uccellini Assistant Administrator for Weather Services and Director of the National Weather Service, National Oceanic and Atmospheric Administration, U.S

    Dr. Louis Uccellini Assistant Administrator for Weather Services and Director of the National Weather Service, National Oceanic and Atmospheric Administration, U.S. Department of Commerce Testimony to the Environment Subcommittee of the Committee on Science, Space, and Technology United States House of Representatives Field Hearing: Weathering the Storm: Improving Hurricane Resiliency through Research July 22, 2019 Good morning Chairwoman Fletcher, Ranking Member Marshall, and Members of the Subcommittee. I am Dr. Louis Uccellini, Director of the National Oceanic and Atmospheric Administration’s (NOAA) National Weather Service (NWS). Within the NWS, NOAA’s National Hurricane Center (NHC) issues the official forecast for all Atlantic and eastern Pacific tropical cyclones (hurricanes, tropical storms and tropical depressions) and their precursors. It is my honor to testify before you today on the state of the United States hurricane forecasting capability; our efforts to improve our understanding and prediction of hurricane impacts from storm surge, heavy precipitation, and high winds; and what hurricane research focus areas are needed to improve prediction. I come before you today to report that hurricane forecasting accuracy has improved tremendously over the past two decades. The NHC track (storm location) forecast errors have decreased every decade since forecast accuracy records were established in the 1960’s, and NHC has set new records almost every year. For perspective, the average two-day Atlantic forecast location error was reduced from around 300 miles (approximately 260 nautical miles (n mi), see Fig. 1) in the 1960s to near 85 miles in the 2010s. The five-day forecast for storm location is now better than the day-and-a-half forecast was in the 1970s.
  • Mariner's Guide for Hurricane Awareness

    Mariner's Guide for Hurricane Awareness

    Mariner’s Guide For Hurricane Awareness In The North Atlantic Basin Eric J. Holweg [email protected] Meteorologist Tropical Analysis and Forecast Branch Tropical Prediction Center National Weather Service National Oceanic and Atmospheric Administration August 2000 Internet Sites with Weather and Communications Information Of Interest To The Mariner NOAA home page: http://www.noaa.gov NWS home page: http://www.nws.noaa.gov NWS marine dissemination page: http://www.nws.noaa.gov/om/marine/home.htm NWS marine text products: http://www.nws.noaa.gov/om/marine/forecast.htm NWS radio facsmile/marine charts: http://weather.noaa.gov/fax/marine.shtml NWS publications: http://www.nws.noaa.gov/om/nwspub.htm NOAA Data Buoy Center: http://www.ndbc.noaa.gov NOAA Weather Radio: http://www.nws.noaa.gov/nwr National Ocean Service (NOS): http://co-ops.nos.noaa.gov/ NOS Tide data: http://tidesonline.nos.noaa.gov/ USCG Navigation Center: http://www.navcen.uscg.mil Tropical Prediction Center: http://www.nhc.noaa.gov/ High Seas Forecasts and Charts: http://www.nhc.noaa.gov/forecast.html Marine Prediction Center: http://www.mpc.ncep.noaa.gov SST & Gulfstream: http://www4.nlmoc.navy.mil/data/oceans/gulfstream.html Hurricane Preparedness & Tracks: http://www.fema.gov/fema/trop.htm Time Zone Conversions: http://tycho.usno.navy.mil/zones.html Table of Contents Introduction and Purpose ................................................................................................................... 1 Disclaimer ...........................................................................................................................................
  • NATIONAL WEATHER SERVICE INSTRUCTION 10-601 JUNE 8, 2012 Operations and Services Tropical Cyclone Weather Services Program, NWSPD 10-6 TROPICAL CYCLONE PRODUCTS

    NATIONAL WEATHER SERVICE INSTRUCTION 10-601 JUNE 8, 2012 Operations and Services Tropical Cyclone Weather Services Program, NWSPD 10-6 TROPICAL CYCLONE PRODUCTS

    Department of Commerce • National Oceanic & Atmospheric Administration • National Weather Service NATIONAL WEATHER SERVICE INSTRUCTION 10-601 JUNE 8, 2012 Operations and Services Tropical Cyclone Weather Services Program, NWSPD 10-6 TROPICAL CYCLONE PRODUCTS NOTICE: This publication is available at: http://www.nws.noaa.gov/directives/. OPR: W/OS21 (T. Schott) Certified by: W/OS21 (M. Tew) Type of Issuance: Emergency SUMMARY OF REVISIONS: This directive supersedes NWS Instruction 10-601, dated June 15, 2011. The following revisions were made to this directive: 1.1.3.3.d Standardizes CONUS policy for storm surge information in the TCP as the combination of storm surge and tides, to emphasize total water level (i.e., inundation) 1.5.2.3 Added WFO Guam policy 1.10.2.3 Added WFO Guam policy 7.1.3.4 Added WFO Guam policy 7.1.4 Updates HLS policy for relationship between the HLS and Rip Current Statement /RP.S/Changes to product examples in Appendix: Updates TWO examples Updates TCU example Updates TCP example with improved storm surge wording Signed May 25, 2012 David B. Caldwell Date Director, Office of Climate, Water, and Weather Services NWSI 10-601 JUNE 8, 2012 Tropical Cyclone Products 1. Tropical Cyclone Forecast and Advisory Products .............................................................4 1.1 Tropical Cyclone Public Advisories (TCP) .............................................................4 1.2 Tropical Cyclone Forecasts/Advisories (TCM) .....................................................11 1.3 Tropical Cyclone Discussions
  • Overview of the NASA Fourth Convection and Moisture Experiment

    Overview of the NASA Fourth Convection and Moisture Experiment

    OverviewOverview ofof thethe NASANASA FourthFourth CConvectiononvection AAndnd MMoistureoisture ExExperimentperiment Ramesh Kakar, Program Scientist Earth Science Enterprise NASA Headquarters Robbie Hood, Lead Mission Scientist NASA / Marshall Space Flight Center MainMain ResearchResearch IssuesIssues SupportingSupporting thethe NASANASA EarthEarth ScienceScience EnterpriseEnterprise • Is the global water cycle through the atmosphere accelerating? • How are variations in local weather, precipitation and water resources related to global climate change? • How well can weather forecasting be improved by new global observations and advances in satellite data assimilation? SpecificSpecific TropicalTropical CycloneCyclone ResearchResearch TopicsTopics • Observation and modeling of processes related to rapid intensification of tropical cyclones • Observation and modeling of storm movement • Improving remote sensing techniques to observe wind, temperature, and moisture in tropical cyclones and their environment • Enhanced understanding of tropical convective system structure and dynamics • Improved understanding of scale interactions between intense convection and mesoscale systems TheThe FourthFourth CConvectiononvection AAndnd MMoistureoisture EXEXperimentperiment • Science Team – 29 Principal Investigators from 5 NASA Centers, 10 universities, and 2 other governmental agencies – Collaborative partners with NOAA, United States Weather Research Program, and Air Force Reserve 53rd Weather Reconnaissance Squadron • Field Operations – Conducted
  • An Improved Hurrican Wind Vector Retrieval Algorithm Using Sea Winds Scatterometer

    An Improved Hurrican Wind Vector Retrieval Algorithm Using Sea Winds Scatterometer

    University of Central Florida STARS Electronic Theses and Dissertations, 2004-2019 2009 An Improved Hurrican Wind Vector Retrieval Algorithm Using Sea Winds Scatterometer Peth Laupattarakasem University of Central Florida Part of the Electrical and Electronics Commons Find similar works at: https://stars.library.ucf.edu/etd University of Central Florida Libraries http://library.ucf.edu This Doctoral Dissertation (Open Access) is brought to you for free and open access by STARS. It has been accepted for inclusion in Electronic Theses and Dissertations, 2004-2019 by an authorized administrator of STARS. For more information, please contact [email protected]. STARS Citation Laupattarakasem, Peth, "An Improved Hurrican Wind Vector Retrieval Algorithm Using Sea Winds Scatterometer" (2009). Electronic Theses and Dissertations, 2004-2019. 4009. https://stars.library.ucf.edu/etd/4009 AN IMPROVED HURRICANE WIND VECTOR RETRIEVAL ALGORITHM USING SEAWINDS SCATTEROMETER by PETH LAUPATTARAKASEM M.S. Florida Atlantic University, 2003 A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the School of Electrical Engineering and Computer Science in the College of Engineering and Computer Science at the University of Central Florida Orlando, Florida Spring Term 2009 Major Professor: W. Linwood Jones © 2009 Peth Laupattarakasem ii ABSTRACT Over the last three decades, microwave remote sensing has played a significant role in ocean surface wind measurement, and several scatterometer missions have flown in space since early 1990’s. Although they have been extremely successful for measuring ocean surface winds with high accuracy for the vast majority of marine weather conditions, unfortunately, the conventional scatterometer cannot measure extreme winds condition such as hurricane.
  • Weather and Forecasting Challenges in the Pacific

    Weather and Forecasting Challenges in the Pacific

    SEPTEMBER 1998 KODAMA AND BUSINGER 523 Weather and Forecasting Challenges in the Paci®c Region of the National Weather Service KEVIN R. KODAMA* Joint Institute for Marine and Atmospheric Research, Honolulu, Hawaii STEVEN BUSINGER Department of Meteorology, University of Hawaii, Honolulu, Hawaii (Manuscript received 10 April 1997, in ®nal form 2 October 1997) ABSTRACT The large area of responsibility covered by the Paci®c Region of the National Weather Service provides a unique set of challenges to operational forecasters. Extratropical, subtropical, and tropical meteorological phe- nomena on a wide range of temporal and spatial scales must be considered on a daily basis. Compounding the problems of forecasting diverse weather for such a large area of responsibility is the fact that the Paci®c Ocean is a data-sparse region. Recent improvements in data collection platforms and the continued progress made by researchers have helped increase the understanding of weather throughout the region, ultimately resulting in improved forecast services. This article provides an overview of some of the weather phenomena encountered in the Paci®c Region and helps set the stage for the accompanying articles that focus on speci®c weather forecasting problems. Some discussion is provided on the impact of the National Weather Service's modernization program on operational forecasting in the region. 1. Introduction weather support under the auspices of the Compact of Free Association with the U.S. government. Although it is the smallest of the six administrative Because of its size, the Paci®c Region's forecasters regions, the Paci®c Region of the National Weather Ser- are frequently challenged with a wide range of mete- vice (NWS), hereafter the ``Paci®c Region,'' covers by orological phenomena that include extratropical, sub- far the largest geographic area of responsibility (AOR).
  • Subtropical Cyclogenesis Over the Central North Pacific*

    Subtropical Cyclogenesis Over the Central North Pacific*

    APRIL 2006 CARUSO AND BUSINGER 193 Subtropical Cyclogenesis over the Central North Pacific* STEVEN J. CARUSO AND STEVEN BUSINGER Department of Meteorology, University of Hawaii at Manoa, Honolulu, Hawaii (Manuscript received 15 November 2004, in final form 20 October 2005) ABSTRACT The occurrence of subtropical cyclones over the central North Pacific Ocean has a significant impact on Hawaii’s weather and climate. In this study, 70 upper-level lows that formed during the period 1980–2002 are documented. In each case the low became cut off from the polar westerlies south of 30°N over the central Pacific, during the Hawaiian cool season (October–April). The objectives of this research are to document the interannual variability in the occurrence of upper-level lows, to chart the locations of their genesis and their tracks, and to investigate the physical mechanisms important in associated surface devel- opment. Significant interannual variability in the occurrence of upper-level lows was found, with evidence suggesting the influence of strong El Niño–Southern Oscillation events on the frequency of subtropical cyclogenesis in this region. Of the 70 upper-level lows, 43 were accompanied by surface cyclogenesis and classified as kona lows. Kona low formation is concentrated to the west-northwest of Hawaii, especially during October and November, whereas lows without surface development are concentrated in the area to the east-northeast of Hawaii. Kona low genesis shifts eastward through the cool season, favoring the area to the east-northeast of Hawaii during February and March, consistent with a shift in the climatological position of the trough aloft during the cool season.
  • 2020 National Winter Season Operations Plan

    2020 National Winter Season Operations Plan

    U.S. DEPARTMENT OF COMMERCE/ National Oceanic and Atmospheric Administration OFFICE OF THE FEDERAL COORDINATOR FOR METEOROLOGICAL SERVICES AND SUPPORTING RESEARCH National Winter Season Operations Plan FCM-P13-2020 Lorem ipsum Washington, DC July 2020 Cover Image: AR Recon tracks (AFRC/53 WRS WC-130J aircraft) from 24 February 2019 on GOES-17 water vapor imagery (warm colors delineate dry air and white/green colors delineate cold clouds). White and brown icons indicate dropsondes. The red arrow indicates the AR axis. FEDERAL COORDINATOR FOR METEOROLOGICAL SERVICES AND SUPPORTING RESEARCH 1325 East-West Highway, SSMC2 Silver Spring, Maryland 20910 301-628-0112 NATIONAL WINTER SEASON OPERATIONS PLAN FCM-P13-2020 Washington, D.C. July 31, 2020 Change and Review Log Use this page to record changes and notices of reviews. Change Page Date| Initial Number Numbers Posted 1 2 3 4 5 6 7 8 9 10 Review Comments Initial Date iv Foreword The purpose of the National Winter Season Operations Plan (NWSOP) is to coordinate the efforts of the Federal meteorological community to provide enhanced weather observations of severe Winter Storms impacting the coastal regions of the United States. This plan focuses on the coordination of requirements for winter season reconnaissance observations provided by the Air Force Reserve Command's (AFRC) 53rd Weather Reconnaissance Squadron (53 WRS) and NOAA's Aircraft Operations Center (AOC). The goal is to improve the accuracy and timeliness of severe winter storm forecasts and warning services provided by the Nation's weather service organizations. These forecast and warning responsibilities are shared by the National Weather Service (NWS), within the Department of Commerce (DOC) and the National Oceanic and Atmospheric Administration (NOAA); and the weather services of the United States Air Force (USAF) and the United States Navy (USN) , within the Department of Defense (DOD).