1 Vertical Structure of Tropical Cyclone Rainbands As Seen by The
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Hurricane Outer Rainband Mesovortices
Presented at the 24th Conference on Hurricanes and Tropical Meteorology, Ft. Lauderdale, FL, May 31 2000 EXAMINING THE PRE-LANDFALL ENVIRONMENT OF MESOVORTICES WITHIN A HURRICANE BONNIE (1998) OUTER RAINBAND 1 2 2 1 Scott M. Spratt , Frank D. Marks , Peter P. Dodge , and David W. Sharp 1 NOAA/National Weather Service Forecast Office, Melbourne, FL 2 NOAA/AOML Hurricane Research Division, Miami, FL 1. INTRODUCTION Tropical Cyclone (TC) tornado environments have been studied for many decades through composite analyses of proximity soundings (e.g. Novlan and Gray 1974; McCaul 1986). More recently, airborne and ground-based Doppler radar investigations of TC rainband-embedded mesocyclones have advanced the understanding of tornadic cell lifecycles (Black and Marks 1991; Spratt et al. 1997). This paper will document the first known dropwindsonde deployments immediately adjacent to a family of TC outer rainband mesocyclones, and will examine the thermodynamic and wind profiles retrieved from the marine environment. A companion paper (Dodge et al. 2000) discusses dual-Doppler analyses of these mesovortices. On 26 August 1998, TC Bonnie made landfall as a category two hurricane along the North Carolina coast. Prior to landfall, two National Oceanographic and Atmospheric Administration (NOAA) Hurricane Research Division (HRD) aircraft conducted surveillance missions offshore the Carolina coast. While performing these missions near altitudes of 3.5 and 2.1 km, both aircraft were required to deviate around intense cells within a dominant outer rainband, 165 to 195 km northeast of the TC center. On-board radars detected apparent mini-supercell signatures associated with several of the convective cells along the band. -
NWS Unified Surface Analysis Manual
Unified Surface Analysis Manual Weather Prediction Center Ocean Prediction Center National Hurricane Center Honolulu Forecast Office November 21, 2013 Table of Contents Chapter 1: Surface Analysis – Its History at the Analysis Centers…………….3 Chapter 2: Datasets available for creation of the Unified Analysis………...…..5 Chapter 3: The Unified Surface Analysis and related features.……….……….19 Chapter 4: Creation/Merging of the Unified Surface Analysis………….……..24 Chapter 5: Bibliography………………………………………………….…….30 Appendix A: Unified Graphics Legend showing Ocean Center symbols.….…33 2 Chapter 1: Surface Analysis – Its History at the Analysis Centers 1. INTRODUCTION Since 1942, surface analyses produced by several different offices within the U.S. Weather Bureau (USWB) and the National Oceanic and Atmospheric Administration’s (NOAA’s) National Weather Service (NWS) were generally based on the Norwegian Cyclone Model (Bjerknes 1919) over land, and in recent decades, the Shapiro-Keyser Model over the mid-latitudes of the ocean. The graphic below shows a typical evolution according to both models of cyclone development. Conceptual models of cyclone evolution showing lower-tropospheric (e.g., 850-hPa) geopotential height and fronts (top), and lower-tropospheric potential temperature (bottom). (a) Norwegian cyclone model: (I) incipient frontal cyclone, (II) and (III) narrowing warm sector, (IV) occlusion; (b) Shapiro–Keyser cyclone model: (I) incipient frontal cyclone, (II) frontal fracture, (III) frontal T-bone and bent-back front, (IV) frontal T-bone and warm seclusion. Panel (b) is adapted from Shapiro and Keyser (1990) , their FIG. 10.27 ) to enhance the zonal elongation of the cyclone and fronts and to reflect the continued existence of the frontal T-bone in stage IV. -
A Long-Lasting Vortex Rossby Wave–Induced Rainband of Typhoon Longwang (2005)
A Long-Lasting Vortex Rossby Wave–Induced Rainband of Typhoon Longwang (2005) YANLUAN LIN, YUANLONG LI, QINGSHAN LI, MINYAN CHEN, FANGHUA XU, YUQING WANG, AND BIN HUANG n 2 October 2005, a record-breaking rainfall event Tsai 2013). As Typhoon Longwang approached the with 152 mm of rainfall in an hour occurred as coast of Fujian Province at 0800 UTC, one type of this OTyphoon Longwang approached Fujian Province, transient rainband in the northeast sector started to China. The severe rainfall was unexpected and signifi- weaken and dissipate (Fig. 1b). At the same time, the cantly underpredicted by the local weather forecasters eyewall underwent an asymmetry transformation and caused a total of 96 deaths. Because of the severe accompanied by a bended convection pattern in the damage over Taiwan and mainland China, the name north (Fig. 1b). The bended convection transformed of Longwang, which means a dragon in charge of into a strong convective band along the eyewall to the rainfall in Chinese, was removed from the name list north and moved outward relative to the storm center for future typhoons. (Fig. 1c). The convective band continued to intensify with a sharp inner edge (Fig. 1d). An hour later, the EVOLUTION AND BASIC FEATURES OF convective band achieved its maximum intensity with THE RAINBAND. The formation and evolution a large area of stratiform precipitation outward and of the rainband associated with the rainfall event was downstream (Fig. 1e). At this time, cloud brightness captured by the radar mosaic produced by the Central temperatures as low as −80°C were measured by a Weather Bureau (CWB) of Taiwan (Fig. -
Learning from Hurricane Hugo: Implications for Public Policy
LEARNING FROM HURRICANE HUGO: IMPLICATIONS FOR PUBLIC POLICY prepared for the FEDERAL INSURANCE ADMINISTRATION FEDERAL EMERGENCY MANAGEMENT AGENCY 500 C Street, S.W. Washington, D.C. 20472 under contract no. EMW-90-G-3304,A001 June 1992 CONTENTS INTRODUCTION ............................... 1.............I PHYSICAL CHARACTERISTICS OF THE STORM . 3 Wind Speeds .3 IMPACTS ON NATURAL SYSTEMS 5 ................................ Biological Systems ....... .................................5 Dunes and Beaches ....... .5............................... Beach Nourishment . .................................7 IMPACTS ON HUMANS AND HUMAN SYSTEMS ............................ 9 Deaths and Injuries ............................ 9 Housing ............................ 9 Utilities ................... 10 Transportation Systems .1................... 10 The Economy ................... 11 Psychological Effects ................... 11 INSURANCE .......................... 13 COASTAL DEVELOPMENT .......................... 14 Setbacks ........................... 15 Coastal Protection Structures .......................... 16 PERFORMANCE OF STRUCTURES ..... .... 18 Effects of Wind and/or Water ...... .... 18 Effects of Water, Waves, or Erosion . .. .18 Effects of Wind .............. .... 19 Foundations .................. .... 21 Slabs ................ .... 22 Piers and Columns ....... .... 22 Pilings............... .... 22 Elevation .................. .... 23 Lower Area Enclosures .... .... 23 Connections ................. ....24 Manufactured Housing .......... .... 24 -
Massachusetts Tropical Cyclone Profile August 2021
Commonwealth of Massachusetts Tropical Cyclone Profile August 2021 Commonwealth of Massachusetts Tropical Cyclone Profile Description Tropical cyclones, a general term for tropical storms and hurricanes, are low pressure systems that usually form over the tropics. These storms are referred to as “cyclones” due to their rotation. Tropical cyclones are among the most powerful and destructive meteorological systems on earth. Their destructive phenomena include storm surge, high winds, heavy rain, tornadoes, and rip currents. As tropical storms move inland, they can cause severe flooding, downed trees and power lines, and structural damage. Once a tropical cyclone no longer has tropical characteristics, it is then classified as a post-tropical system. The National Hurricane Center (NHC) has classified four stages of tropical cyclones: • Tropical Depression: A tropical cyclone with maximum sustained winds of 38 mph (33 knots) or less. • Tropical Storm: A tropical cyclone with maximum sustained winds of 39 to 73 mph (34 to 63 knots). • Hurricane: A tropical cyclone with maximum sustained winds of 74 mph (64 knots) or higher. • Major Hurricane: A tropical cyclone with maximum sustained winds of 111 mph (96 knots) or higher, corresponding to a Category 3, 4 or 5 on the Saffir-Simpson Hurricane Wind Scale. Primary Hazards Storm Surge and Storm Tide Storm surge is an abnormal rise of water generated by a storm, over and above the predicted astronomical tide. Storm surge and large waves produced by hurricanes pose the greatest threat to life and property along the coast. They also pose a significant risk for drowning. Storm tide is the total water level rise during a storm due to the combination of storm surge and the astronomical tide. -
Hurricane Boundary Layer Height Relative to Storm Motion from GPS Dropsonde Composites
atmosphere Article Hurricane Boundary Layer Height Relative to Storm Motion from GPS Dropsonde Composites Yifang Ren 1, Jun A. Zhang 2,3,* , Stephen R. Guimond 4,5 and Xiang Wang 6 1 The Center of Jiangsu Meteorological Service, Nanjing 21008, China; [email protected] 2 Cooperative Institute for Marine and Atmospheric Studies, University of Miami, Miami, FL 33149, USA 3 NOAA/AOML/Hurricane Research Division, Miami, FL 33149, USA 4 Joint Center for Earth Systems Technology, University of Maryland Baltimore County, Baltimore, MD 21250, USA; [email protected] 5 NASA Goddard Space Flight Center (GSFC), Greenbelt, MD 20771, USA 6 Centre of Data Assimilation for Research and Application, Nanjing University of Information Science & Technology, Nanjing 210044, China; [email protected] * Correspondence: [email protected] Received: 9 May 2019; Accepted: 10 June 2019; Published: 21 June 2019 Abstract: This study investigates the asymmetric distribution of hurricane boundary layer height scales in a storm-motion-relative framework using global positioning system (GPS) dropsonde observations. Data from a total of 1916 dropsondes collected within four times the radius of maximum wind speed of 37 named hurricanes over the Atlantic basin from 1998 to 2015 are analyzed in the composite framework. Motion-relative quadrant mean composite analyses show that both the kinematic and thermodynamic boundary layer height scales tend to increase with increasing radius in all four motion-relative quadrants. It is also found that the thermodynamic mixed layer depth and height of maximum tangential wind speed are within the inflow layer in all motion-relative quadrants. The inflow layer depth and height of the maximum tangential wind are both found to be deeper in the two front quadrants, and they are largest in the right-front quadrant. -
Characteristics of Supercells in the Rainband of Numerically Simulated Cyclone Sidr
SOLA, 2010, Vol. 6A, 025−028, doi:10.2151/sola.6A-007 25 Characteristics of Supercells in the Rainband of Numerically Simulated Cyclone Sidr Nasreen Akter1 and Kazuhisa Tsuboki1, 2 1Hydrospheric Atmospheric Research Center, Nagoya University, Nagoya, Japan 2Frontier Research Center for Global Change, JAMSTEC, Yokohama, Japan (Figs. 1b and 1c). The cell indicated in Fig. 1b is ~116 km away Abstract from the radar, and its local altitude is ~1 km. Also, no sounding data are available. The observed data are not sufficient for inves- Cyclone Sidr had an intense rainband east of the cyclone tigation of the detailed structure and intensity of the convective center. The rainband exhibited two strong convective lines (band cells along the band. axes) composed of convective cells. To study the characteristics of Therefore, the present study aims to clarify the characteristics the convective cells, a simulation was performed at 1-km resolu- of the convective cells in the rainband of Cyclone Sidr over the tion by using a cloud-resolving model. In both band axes, some sea and the environmental factors affecting cell development. For cells showed the characteristic structure of a supercell. Supercells this purpose, a high-resolution simulation was performed using within the outer axis had stronger updraft, more intense precipita- the Cloud-Resolving Storm Simulator (CReSS) model (Tsuboki tion, and a longer lifetime than those of the inner axis. The values and Sakakibara 2007). of the CAPE and helicity are different in the strong vertical shear environment of the inner and outer axes. A large moisture flux was present throughout the troposphere on the east side of the outer 2. -
The Precipitation Structure of the Mediterranean Tropical-Like Cyclone Numa: Analysis of GPM Observations and Numerical Weather Prediction Model Simulations
remote sensing Article The Precipitation Structure of the Mediterranean Tropical-Like Cyclone Numa: Analysis of GPM Observations and Numerical Weather Prediction Model Simulations Anna Cinzia Marra 1, Stefano Federico 1 , Mario Montopoli 1 , Elenio Avolio 2 , Luca Baldini 1 , Daniele Casella 1, Leo Pio D’Adderio 1, Stefano Dietrich 1 , Paolo Sanò 1 , Rosa Claudia Torcasio 1 and Giulia Panegrossi 1,* 1 Institute of Atmospheric Sciences and Climate, National Research Council (ISAC/CNR), 00133 Rome, Italy 2 Institute of Atmospheric Sciences and Climate, National Research Council (ISAC/CNR), 88046 Lamezia Terme, Italy * Correspondence: [email protected]; Tel.: +39-06-4993-4274 Received: 30 May 2019; Accepted: 11 July 2019; Published: 17 July 2019 Abstract: This study shows how satellite-based passive and active microwave (MW) sensors can be used in conjunction with high-resolution Numerical Weather Prediction (NWP) simulations to provide insights of the precipitation structure of the tropical-like cyclone (TLC) Numa, which occurred on 15–19 November 2017. The goal of the paper is to characterize and monitor the precipitation at the different stages of its evolution from development to TLC phase, throughout the storm transition over the Mediterranean Sea. Observations by the NASA/JAXA Global Precipitation Measurement Core Observatory (GPM-CO) and by the GPM constellation of MW radiometers are used, in conjunction with the Regional Atmospheric Modeling System (RAMS) simulations. The GPM-CO measurements are used to analyze the passive MW radiometric response to the microphysical structure of the storm, while the comparison between successive MW radiometer overpasses shows the evolution of Numa precipitation structure from its early development stage on the Ionian Sea into its TLC phase, as it persists over southern coast of Italy (Apulia region) for several hours. -
Tropical Cyclones: Meteorological Aspects Mark A
Tropical Cyclones: Meteorological Aspects Mark A. Lander1 Water and Environmental Research Institute of the Western Pacific, University of Guam, UOG Station, Mangilao, Guam (USA) 96923 Sailors have long recognized the existence of deadly storms in Every year, TCs claim many lives—occasionally exceeding tropical latitudes where the weather was usually a mix of bright sun and 100,000. Some of the world’s greatest natural disasters have been gentle breezes with quickly passing showers. These terrifying storms associated with TCs. For example, Tropical Cyclone 02B was the were known to have a core of screaming winds accompanied by deadliest and most destructive natural disaster on earth in 1991. The blinding rain, spume and sea spray, and sharply lowered barometric associated extreme storm surge along the coast of Bangladesh was the pressure. When the sailors were lucky enough to survive penetration primary reason for the loss of 138,000 lives (Joint Typhoon Warning to the core of such violent weather, they found a region of calm. This Center, 1991). It occurred 19 years after the loss of ≈300,000 lives in region is the signature characteristic and best-known feature of these Bangladesh by a similar TC striking the low-lying Ganges River storms—the eye (Fig. 1). region in April 1970. In a more recent example, flooding caused by These violent storms of the tropical latitudes were known to be Hurricane Mitch killed 10,000+ people in Central America in Fall seasonal, hence their designation by Atlantic sailors as “line” storms, 1998. Nearly all tropical islands—the islands of the Caribbean, Ha- in reference to the sun’s crossing of the line (equator) in September (the waii, French Polynesia, Micronesia, Fiji, Samoa, Mauritius, La Re- month of peak hurricane activity in the North Atlantic). -
An Analysis of Hurricane Irma's Maximum Winds in South Florida
An Analysis of Hurricane Irma’s Maximum Winds in South Florida Andrew B. Hagen, Kevin Scharfenberg, Arlena Moses, Stephen Konarik, Robert Garcia Hurricane Irma struck South Florida on 10 September 2017 and caused significant wind damage to structures and trees as well as widespread power loss. Irma caused more than personal inconvenience to many South Floridians, and its aftermath left people asking how they can be better prepared for the next hurricane. From a wind impact perspective, it is important to spatially quantify the wind magnitude so that residents and business owners of South Florida can have a better understanding of the maximum wind speeds experienced in their neighborhood during Irma. Hurricane Irma’s winds have been analyzed across the National Weather Service Miami County Warning Area, which includes the Florida Peninsula from Lake Okeechobee southward and adjacent coastal waters of the Gulf of Mexico and Atlantic Ocean. All available data from surface- based weather stations and anemometers are incorporated. WSR-88D Doppler velocity data were also analyzed and used to fill in the gaps for locations where observations are sparse. These data were further augmented with results of ground wind damage surveys. Detailed, color-contoured maps of sustained winds and gusts have been created in addition to a list of observations. For the purposes of consistency on the color-contoured map, all sustained wind observations are converted to a 10 meter, one minute average using standard conversion metrics. The results indicate that sustained hurricane force winds up to Category 2 strength on the Saffir-Simpson Hurricane Wind Scale with higher gusts occurred in southern portions of coastal Collier County, including portions of the Naples area. -
A Technique to Determine the Radius of Maximum Wind of a Tropical Cyclone
OCTOBER 2008 LAJOIEANDWALSH 1007 A Technique to Determine the Radius of Maximum Wind of a Tropical Cyclone FRANCE LAJOIE AND KEVIN WALSH School of Earth Sciences, University of Melbourne, Parkville, Victoria, Australia (Manuscript received 2 October 2007, in final form 22 January 2008) ABSTRACT A simple technique is developed that enables the radius of maximum wind of a tropical cyclone to be estimated from satellite cloud data. It is based on the characteristic cloud and wind structure of the eyewall of a tropical cyclone, after the method developed by Jorgensen more than two decades ago. The radius of maximum wind is shown to be partly dependent on the radius of the eye and partly on the distance from the center to the top of the most developed cumulonimbus nearest to the cyclone center. The technique proposed here involves the analysis of high-resolution IR and microwave satellite imagery to determine these two parameters. To test the technique, the derived radius of maximum wind was compared with high-resolution wind analyses compiled by the U.S. National Hurricane Center and the Atlantic Oceano- graphic and Meteorological Laboratory. The mean difference between the calculated radius of maximum wind and that determined from observations is 2.8 km. Of the 45 cases considered, the difference in 50% of the cases was Յ2 km, for 33% it was between 3 and 4 km, and for 17% it was Ն5 km, with only two large differences of 8.7 and 10 km. 1. Introduction Another sensor on board a polar-orbiting satellite that can produce high-resolution surface wind fields r To determine m, the radius of maximum wind for a over the ocean is the Wind Field Synthetic Aperture tropical cyclone, one needs to analyze the strong sur- Radar (WiSAR). -
P9.6 Radar Observations of a Tornadic Severe Frontal Rainband
P9.6 RADAR OBSERVATIONS OF A TORNADIC SEVERE FRONTAL RAINBAND Jenni Rauhala* and Ari-Juhani Punkka Finnish Meteorological Institute, Helsinki, Finland 1. INTRODUCTION Although a warning for thunderstorm wind gusts was issued well before the onset of the event, the On the afternoon of 26 August 2005, severe magnitude of the damage was not anticipated by FMI convective storms caused vast wind damage in forecasters. western Finland: 382 wind damage or flood reports A closer look into radar reflectivity and velocity and 9 tornado cases (Fig. 1). Two rainbands patterns indicated small scale bowing segments in the developed over western Finland: while, the pre-frontal reflectivity fields co-located with mesovortices, similar rainband caused minor flooding, almost all of the to those shown in previous studies (e.g. Weisman and observed severe weather (Fig. 1) occurred along the Trapp 2003) to be capable of producing both straight- second rainband associated with a cold front. line wind damage and tornadoes. The storm environment, with significant low level vertical wind shear, had likely influenced the mesovortex formation. Fortunately, some of these mesovortices occurred near a polarimetric radar, which offered insight into their small scale precipitation structures. 2. DATA The case occurred partly over the Helsinki Testbed mesoscale observation network area (Saltikoff et al. 2005) during the August 2005 campaign period. The radar analysis was based on data from two 5.32 cm Doppler radars of the FMI and the polarimetric radar of the University of Helsinki. The lowest elevations were not used for velocity analysis because of velocity folding. Complete volume scans from FMI radars and the Kumpula radar were available for 5-minute and 10-minute intervals, respectively.