What is a Cyclone?Tropical CycloneTypes of Tropical Cyclone,Hurricanes, Typhoons, Cyclone and TornadoesMesocyclonesPolar Lows or Arctic HurricanesExtratropical or Midlatitude CyclonesTypes of Cyclones in India, This site is using cookies under cookie policy . is the expectation that the tropical storm will continue to develop from [22], The combined effects of hurricanes Ingrid and Manuel affected about two-thirds of Mexico. Its minimum pressure was 924 mbar (hPa).[1]. Instruments include satellite radiometers (IR, visible, and microwave), precipitation and cloud radars (ground, airborne, and satellite), satellite scatterometers, and synthetic aperture radars (SAR). Derived from science Dong, K., C. J. Neumann, 1986: On the relative motion of binary tropical cyclones. 8.14). In this way, the results in this section can be extended to both a synoptic-scale environment and to the Fujiwhara interaction of two or more tropical cyclones. 163. The typical distribution of inertial stability values is represented here by comparison with. , violent content, anything that would not be family friendly or appropriate for a child to read. SYNOP codes from weather stations and buoys. Ingrid's impact - the tropical cyclone that crossed three states The gyres are illustrated for both a NH and a SH tropical cyclone. The storm begins as a tropical disturbance, which typically occurs when loosely organized cumulonimbus clouds in an easterly wave begin to show signs of a weak circulation. Extended best track of North Pacific Typhoon Tokage (2004). Finally, only intense tropical cyclones typically complete ET124,136 since they must survive the sheared midlatitude environment until they have completed transition. 8.56). 18. A. Klinger, 1999: A mechanism for generating ENSO decadal variability. [20] After a restriction on the news in 2010 due to the local drug war, members of a citizen alert system in Tamaulipas used Twitter to notify about flooding, missing people, and the need for assistance. 230. Recall that the (specific) absolute angular momentum, , is defined as. Eyewall replacement cycles can last as short as 1218 hours to as long as 23 days (Figs. In general, TC eyewalls contract as they strengthen to the intense TC threshold. what is a dragon worth in adopt me; how to cash a payable order from dvla. stages of development of tropical cyclone ingrid marlene wilkerson net worth nikola jokic hand size ronnie green obituary. As we discussed in Section 8.2.3.2, the inertial stability of a tropical cyclone increases with increasing intensity. Fig. Ferreira, R. N., W. H. Schubert, 1999: The role of tropical cyclones in the formation of tropical upper-tropospheric troughs. Example of vertical wind shear calculation. Maps of the mean minimum sustainable surface pressure, a measure of potential intensity, in February (upper) and September (lower). Since relative vorticity is calculated by taking spatial gradients of the vector wind. The environmental wind shear will cause the storm to reorganize through induced convection on the downshear side of the storm that will initially create an asymmetry. Discuss the stage of development of the tropical cyclone ingrid. Intensity scales and satellite interpretation techniques are described. Starting in Queensland, Ingrid crossed Cape York at a remote location, uprooting trees and stripping the foliage and bark from many more. 83. (Upper) Tracks of all 2005/2006 Australian region tropical cyclones; and (lower) a satellite montage of severe tropical cyclones Glenda, Monica and Larry. With this in mind, we will discuss absolute angular momentum, remembering that we are discussing specific absolute angular momentum. The CDO appearance is judged on its size and degree of banding. The (new) internal boundary layer will form in the timescale of an inertial period of the storm, which is about an hour in the strong wind part of the storm. Allan, R. J., 2000: ENSO and climatic variability in the past 150 years. It would seem that the case is closed but science is rarely that straightforward! Over the next several days, the hurricane delivered historic amounts of rainfall across North and South Carolina . At this time, Rita had peak winds of 45 m s, Fig. Part I: Observations. Frank, N. L., 1969: The "Inverted V cloud pattern An easterly wave? The storm system is likely to move northwestwards and weaken into low pressure. Fig. Liu, K.-., M. L. Fearn, 1993: Lake-sediment record of late Holocene hurricane activities from coastal Alabama. 8.33). Thus, we will use f~ 10-5 s-1. For example, major Hurricane Ivan weakened, from a category 5 to a category 4, as it approached Jamaica from the southeast, in part because of an eyewall replacement cycle. the black boy looks at the white boy pdf operational definition of confidence. The SaffirSimpson scale was initially intended to provide a link between the observed damage and the effects of wind, pressure and storm surge that could lead to such damage. the: The eye pattern identifies the temperature contrast between the warmest part of the eye and the coldest surrounding convection within 55 km (e.g., Fig. 86. where V is the scale speed, L is the scale distance and f is the Coriolis parameter. The extreme waves arrived only shortly before the main center of the storm. Early statistical predictions of North Atlantic seasonal hurricane activity relied predominantly on the phases of ENSO (either prior to the season or predicted for the peak of the season) and the QBO, as well as Caribbean sea level pressures. No even this region can be impacted by tropical cyclones! decision to locate the factory in this area. 8.32), the link between the branch sinking far from the storm center and the boundary layer inflow is not supportable from observations. 8.16. NASA image courtesy Jeff Schmaltz, MODIS Land Rapid Response Team at NASA GSFC. [7], On 11 March, officials in the Northern Territory advised the 4,000 residents of Nhulunbuy to evacuate to higher ground. However, implicit in this operational genesis criterion Make your forecast for each storm: Using the materials we have covered, you should have been able to devise some simple forecast rules to guide your forecasts of the next stage of development for these two storms. (b) At the "old" eye radius, the radius is unchanged while the wind speed has decreased. https://bit.ly/2W4dIsY It's a Super Simple weather song! stage of development of ingrid tropical cyclone. This really happened, We recently discussed the importantance of omega-3 fatty acids for maintaining good health. Lower panel is adapted from Gray (1984). This gives us the characteristics of the moist adiabatic outflow of the Carnot engine (Fig. 8.56). The most recently identified mechanisms contributing to tropical cyclogenesis in each of the affected ocean basins are given in Fig. ), In Far North Queensland, several hundred residents, including some in Aboriginal communities, evacuated from areas deemed vulnerable to shelters by 9 March. Cloudy? Hurricane Florence Case Study - Internet Geography 181. "[10] At around 1115UTC on September16, Ingrid made landfall just south of La Pesca, Tamaulipas in northeastern Mexico, after having weakened into a strong tropical storm with 100km/h (65mph) winds. Foley, G. R., B. N. Hanstrum, 1994: The capture of tropical cyclones by cold fronts off the west coast of Australia. Karyampudi, V. M., T. N. Carlson, 1988: Analysis and numerical simulations of the Saharan air layer and its effect on easterly wave disturbances. When a tropical cyclone moves into a hostile environment it will either decay (Fig. "A" marks the rainfall maximum along the front north of Agnes and "B" marks rainfall maximum in the right forward quadrant of Agnes. Frank, W. M., E. A. Ritchie, 2001: Effects of vertical wind shear on the intensity and structure of numerically simulated hurricanes. 8.7). [11], Damages from the storm in Queensland amounted to A$5.3million (US$4.1million).[12]. Volunteers delivered about 600blankets and various cleaning supplies to the town of Pnuco. The following animation of the evolution of Hurricane Isabel (2003) demonstrates the development of the clear eye as the storm intensifies; eyewall vortices and development of an asymmetric eye, which then resymmetrizes are also evident. Current Trajectories on the Storm predict it re . In March 2012, the wind speeds for Categories 3-5 hurricanes were modified to resolve rounding issues associated with conversion between units. A. For cyclogenesis, the easterly wave must interact with the convectively active cycle of the MJO in regions of dynamic instability over the warm tropical waters. [6] On the western coast of Queensland, residents took precautions prior to a weakened Ingrid as a "code blue alert" was declared. Given the weak environmental winds near the surface, some vertical wind shear is needed to advect the storm along.93,94 Without this environmental advection, a storm will have relatively slow motion. 56. Images are taken near 0000 UTC 21 Sep 2005. Broecker, W. S., 1991: The great ocean conveyor. [30], The twin impacts of hurricanes Ingrid and Manuel prompted officials in Mexico to declare a state of emergency in 155municipalities in Veracruz, Tamaulipas, Chiapas, Oaxaca, Guerrero, and Chihuahua. Article shared by : ADVERTISEMENTS: The development of cycle of tropical cyclones may be divided into three stages. So the multiple storm formation mode of genesis appears to be present in the African monsoon. To close the system, stages of development of tropical cyclone ingrid - asrefava.ir The storm surge scale was shown to be invalid, as the surge is affected by parameters such as storm size and past motion and local bathymetry. 8.24b) indicate the presence of a mesoscale convective vortex, a feature that sometimes forms in the stratiform region of decaying MCSs. Tropical cyclones develop in tropical oceans at least 5 - 30 latitude north or south of the equator, where the sea temperature is at least 27 C. 2. 37. In a phenomenal re-birth, Ingrid rapidly re-intensified, going from tropical storm strength back to a Category 4 cyclone with maximum sustained winds estimated at 120 knots (138 mph) by the Joint Typhoon Warning Center in the span of just 12 hours. This distribution of convection (and associated lightning) is consistent with the development of deep divergent circulations in the storms75 and the greater disruption to the weaker system. 119. Another interpretation of the Rossby number is that it gives the ratio of the vorticity of the flow to the Earth's vorticity, f. The magnitude of the Rossby number gives insight into the type of force balance dominating: Thus, calculation of the Rossby number for various regions of a typical tropical cyclone will tell us about the important force balances in this region. Easterly waves form in an environment similar to the first multiple storm formation mode of genesis pictured in Fig. This last constraint is not applied uniformly. Tropical Depression Nine strengthened into Humbertothe next A circulation system goes through a sequence of stages as it intensifies into a mature tropical cyclone. RESEARCH TOPIC: THE DEVELOPMENT AND IMPACT OF TROPICAL CYCLONES Guidelines for discussion Choose ONE of the following Tropical cyclones: Hagibis Nivar Ingrid Florence Eloise The desktop research must centre around ONE of the tropical cyclones. C. Pertaining to an Emperor, the_______ classifies elements in categories showing which elements possess similar characteristics and react similarly with other elements. Why can category 1 tropical cyclones be more destructive (damaging) than category - 27072472 Because they show the internal structure of TCs, microwave images are helping to identify intense cyclones many of which display concentric eyewall structures (e.g., Fig. Lightning flashes and radar reflectivity of Hurricane Charley (2004). This increase in the local vorticity spins up the eye. STAGES OF DEVELOPMENT OF THE MID-LATITUDE CYCLONE: Initial stage Pressure differences exist between the warm tropical air and cold polar air resulting in a pressure gradient (around polar front) Due to a disturbance in winds high in the atmosphere or mountain ranges a wave forms A cell of low pressure begins Mature stage Part of the record-breaking 2005 Atlantic hurricane season, which included three of the ten most intense Atlantic hurricanes ever in terms of barometric pressure (along with #4 Exploiting the uniqueness of the soloMERTM technology for the development of next-generation, super-potent drug modalities for chronic autoimmune inflammation diseases, and beyond - April 2022 Opportunities and Challenges in Early-Stage TB Drug Discovery: Targeting DNA Replication as a Case Study - April 2022 Transcribed image text: RESEARCH TOPIC: THE DEVELOPMENT AND IMPACT OF TROPICAL CYCLONES Guidelines for discussion Choose ONE of the following Tropical cyclones: Hagibis Nivar Ingrid Florence Eloise The desktop research must centre around ONE of the tropical cyclones. Copyright 2011, University Corporation for Atmospheric Research. 8.68. [3] Tourists in resorts on Lizard Island and Cape Tribulation were evacuated the same day. Something went wrong. Tropical Cyclone 02B made landfall in Chittagong, Bangladesh on 29 April 1991 at about 1900 UTC. Maloney, E. D., D. L. Hartmann, 2000: Modulation of hurricane activity in the Gulf of Mexico by the Madden-Julian oscillation. Schematic of the cross-section through a tropical cyclone showing the vertical airflow and microphysics in the eyewall and rainbands. The (i) boundary layer inflow, (ii) eyewall, (iii) cirrus shield, (iv) rainbands, and (v) upper tropospheric outflow (Fig. In the monsoon confluence zones, genesis may be initiated through easterly waves that propagate into the region. Fig. Evans, J. L., K. McKinley, 1998: Relative timing of tropical storm lifetime maximum intensity and track recurvature. Tropical Cyclone Ingrid developed to a Category (Cat) 5 system by 8 March and around 0600 CST on 10 March Ingrid made landfall on Cape York as a Cat 4 tropical cyclone. City University of Hong Kong, (2000)138 add another requirement: that the storm reintensify (in terms of pressure) after completing ET. Fig. Reed, R. J., D. C. Norquist, and E. E. Recker, 1977: The structure and properties of African wave disturbances as observed during phase III of GATE. Fig. 8.44, b and d) and is the preferred channel for observing tropical cyclone structure and intensity changes. Vitart, F. D., 2006: Seasonal forecasting of tropical storm frequency using a multi-model ensemble. Pratt, A. S., 2005: Tropical cyclogenesis forecasting skill of the Global Forecasting System (GFS) during the 2002 and 2003 Atlantic hurricane seasons., Masters Thesis, Department of Meteorology, Pennsylvania State University, 135 pp. An exception to this rule is the role of the TUTT in intensifying western North Pacific storms. Thus, while an intense symmetric cyclone is more protected from influences that might weaken it, its strong inertial stability does not extend to the tropopause. Fig. Finally, vertical variation of both the tropical cyclone and its environment mean that its motion is not strictly that expected from barotropic dynamics. Willoughby, H. E., 1990: Gradient balance in tropical cyclones. Kerry received his doctorate from MIT in 1978, then joined the faculty of UCLA. Madden, R. A., P. R. Julian, 1972: Description of global-scale circulation cells in the tropics with a 40-50 day period. If a tropical cyclone moves from one region to another, it is typically renamed to the next name on the list in the new region. November 1, 2018. Read More 6 The coastal region was devastated by peak 1minute averaged surface winds in excess of 72 m s-1 (260 km h-1), 898 hPa minimum pressure (SaffirSimpson Category 5), and a 6.1 meter storm surge. 8.64). NWS JetStream - Tropical Cyclone Structure - National Weather Service A seasonal forecast model must demonstrate skill against a "no skill" baseline prediction to be useful.200 The most common no skill forecast used for operational weather forecast models is a combination of climatology and persistence (known as CLIPER). For a more complete, mathematical discussion of this theory, the reader is referred to the source papers.89,90. On August28, a tropical wave exited the west coast of Africa, which moved westward across the Atlantic Ocean without development. Lamb, P. J., 1978: Large-scale tropical Atlantic surface circulation patterns associated with sub-Saharan weather anomalies. [13] Ingrid rapidly weakened into a tropical depression over land,[14] and although convection temporarily reorganized,[15] the circulation dissipated on September17. cyclone Carnot engine to determine the fraction of the heat energy that So, the necessary but not sufficient conditions for tropical cyclogenesis71 must still be satisfied in this more unusual path to genesis. 156. (b) Picture of flooded areas in Pennsylvania (more than 1500 km from where Agnes made landfall). 177. For Japan, the season was particularly devastatingten typhoons made landfall in Japan that year (many of these were either undergoing or having completed extratropical transition). If the upper trough breaks off from the westerlies (a Rossby wave break)68 and becomes a cut-off low, its scale and speed of motion are favorable for the genesis of a subtropical storm. Part I: Patterns and cycles. 2.40). Hurricane activity is suppressed during the easterly wind phase of the QBO (lower, unshaded region). The shear pattern examines the distance from the low level center to the CDO, with the principle being that greater involvement of the low level center with the deep convection indicates a stronger system. 165. 8.67). New satellite analyses are being developed to objectively identify eyewall replacement cycles. 5. (a) Interactions of Agnes and midlatitude trough. 8B9.4. Sadler, J. C., 1978: Mid-season typhoon development and intensity changes and the tropical upper tropospheric trough. It was not until 1984 that scientists from Colorado State University began publishing regular forecasts of annual tropical cyclone activity for the North Atlantic basin.162,170. As a tropical cyclone makes landfall, the surface winds decrease faster than winds above, creating vertical wind shear which allows for tornadoes to develop. IR-BD enhanced images of Tropical Cyclone Indlala (2001) with estimated central pressure of (a) 994 hPa, (b) 984 hPa, (c) 967 hPa, and (d) 927 hPa. If you walk around and around a circular swimming pool you can force the water into rotation in the same direction. ), which is related to storm intensity (Fig. [17], Throughout Mexico, Ingrid killed 32people, mostly due to flooding and mudslides. 127. Development of tropical cyclones - Met Office Adem, J., P. Lezama, 1960: On the motion of a cyclone embedded in a uniform flow. lightning does occur in TCs, it most often happens in the convective outer Part I: Climatology and mean structure changes. The roots of this story are a little unclear, but one version states that a group of pilots, including Lt Col Joe Duckworth, were comparing the abilities of their planes. QuikSCAT scan of Tropical Cyclone Catarina at 0845 UTC 26 Mar 2004, when Catarina was still intensifying. Kossin, J. P., W. H. Schubert, 2001: Mesovortices, polygonal flow patterns, and rapid pressure falls in hurricane-like vortices. This relationship has been linked89 to the intensity of the storms at the time of ET onset. Studies of the easterly wave-MJO system confirmed that barotropic dynamics are an important contributor to coupling the convectively active phase of the MJO with a potential increase in tropical cyclogenesis in the tropical Pacific and Atlantic.148,149,150 The anomalous westerly jet associated with the westerly phase of the MJO is thought to be crucial in the barotropic formation of incipient disturbances across the entire tropical Pacific. 8.42, lower panels), providing a reliable indication of a strengthening tropical cyclone. As discussed in Section 8.5, tropical cyclones undergoing ET may initially weaken as they move into the extratropics, but they can reintensify into midlatitude storms that are occasionally more intense than their tropical selves (e.g. A Carnot engineg is a closed system in which heat energy is converted to mechanical energy. The warm ocean waters of the tropics provide the energy source for the tropical cyclone. 138. This positive relationship between the SAL and tropical cyclone formation is not ubiquitous however. (Velden et al. 20. Any change in surface roughness (landfall or change in land use) will result in the formation of a new "internal" boundary layer that is in balance with the new surface. An incipient tropical cyclone with weak convection will be more susceptible to weakening even in regions of very low vertical wind shear. ? Storm intensity is only weakly, and indirectly, related to its motion. When the disturbance size is wider than LR, it persists; systems that are smaller than LR will disperse (Fig. The figure shows the lightning flashes around (a) Hurricane Bertha (1996) and (b) weakening Tropical Storm Alberto (1994). (Image courtesy of Mr. Michael Bell and Dr. Wen-Chau Lee). Risk of power Zangief is a massive fighter, weighing 400 lbs and standing slightly over 7 feet tall, placing him as one of the tallest characters in the entire Street Fighter roster. What kind of environmental support is necessary for extratropical transition? Thus, the TUTT could be a consequence, rather than a driver, of tropical cyclogenesis. After the storm, the Mexican government declared several municipalities to be in states of emergency. 8.15) critically influence the subsequent distribution of significant weather due to that tropical cyclone. [Available online at. Further, a downwards flux of heat through the top of the boundary layer also warms it. Let us look at the cyclone stages in detail: Formation and Initial Development Stage. Another multi-year modulator of interannual tropical cyclone activity is the Quasi Biennial Oscillation of the stratospheric zonal wind (Fig. d For example, during an eyewall replacement cycle (Section 8.4.5.3). A hostile environment includes at least one of the following: strong vertical wind shear (in excess of 10-15 m/s over a deep layer) These stages are not discrete entities, but represent a continuous process. A 2.7 m storm surge hit the . A total of 490 transects on 82 sites was surveyed on 32 study reefs . Indeed, the two most devastating tropical cyclones on record occurred in this region (. Can you think of some issues that need to be considered? Factors that influence motion are described. Some roof and structural damage. Meteorologists have divided the development of a tropical cyclone into four stages: Tropical disturbance, tropical depression, tropical storm, and full-fledged tropical cyclone. Fig. A number of new diagnostics have been proposed to characterize ET. So we see that, storms forming under the right conditions farther from the equator can become tropical cyclones. We can picture the outcome of this weakening by making use of thermal wind balance of a symmetric vortex: the lack of a moisture source over land weakens the convection and associated subsidence in the eye weakens the upper tropospheric warm core, raising the central pressure of the storm. The final section describes societal impacts. However, it was downgraded to a Category2 storm as it crossed the peninsula north of the towns of Coen and Lockhart River. 102. Lightning generated in the unstable coastal zone can also create a hazard (generally just offshore) to the population near the coast.38,39. 8.19). Fig. Caution should be used when considering interannual variability and ENSO. While post-landfall structure changes generally lead to a decrease in the near-surface wind speeds as described above, the roughness of the terrain can contribute to regions in which the gusts are stronger than the frictionally-reduced surface winds. 168. Southern Hemisphere tropical cyclones are generally weaker than storms in the North Pacific and Atlantic basins; The extension of the subtropical jet into tropical latitudes in the Southern Hemisphere acts to constrain the tracks of tropical cyclones. That night of 12 November 1970 the storm made landfall on the coast of East Pakistan (now Bangladesh). (Type your response in the box below.). However, that hypothesis was contradicted by another study that found that the fraction of systems developing from convective cluster to tropical storm is unchanged between "favorable" [convection active] and "unfavorable" [convection suppressed] phases of the MJO.140 Since the vast majority of tropical cyclones in the Australian region form near the axis of the Australian summer monsoon,15 modulation of this feature by the MJO has been linked to tropical cyclone activity in that region. The Joint Typhoon Warning Center expects Ingrid to continue to intensify as it moves closer to northeastern Australia, possibly coming ashore as early as March 9. 850 hPa wind observations (dots) for Hurricane Diana on 12 Sep 1984, symmetric gradient wind (solid) and gradient wind change (dash) deduced from the observed height field. Schematic of the asymmetric (NH and SH) tropical cyclone calculated for a symmetric tropical cyclone in a more realistic environment with a nonzero relative vorticity gradient that results in gyres that include Coriolis and relative vorticity effects. stages of development of tropical cyclone ingridcynon valley history. 5? Molinari, J., D. Vollaro, and K. L. Corbosiero, 2004: Tropical cyclone formation in a sheared environment: A case study. 8B7.2), QuikSCAT recorded the surface winds (Fig. Binary interactions occurred when the tropical cyclone centers were separated by distances of less than 1300 1400 km, but this critical separation distance depending on the sizes of the interacting systems.40,215 Of these interacting cyclones, 70% orbited cyclonically around one another with slower speeds of rotation around the other vortex with larger separation distance. He received his Ph.D. from the Department of Geophysical Sciences at the University of Chicago in 1964 and has served since 1961 on the Department of Atmospheric Science faculty at the Colorado State University. Merrill, R. T., 1984: A comparison of large and small tropical cyclones. Until Catarina, the cooler SST of the tropical South Atlantic and the strong vertical wind shear were thought to preclude tropical cyclone formation. IR analysis is also used to identify annular hurricanes objectively.107 Annular hurricanes have strong and steady intensities and are generally 1040% larger than normal hurricanes in the Atlantic and East Pacific. 223. Now lets calculate the Rossby number for each 8.3) or the US Joint Typhoon Warning Center (JTWC) in Pearl Harbor. Thermal (convective) instability may enhance the eyewall convection, contributing to overshooting convection into the stratosphere. Before discussing interannual variability, it is important to understand the difference between annual cyclone activity (frequency and intensity) and the severity of cyclone impacts (landfall frequency, fatalities, and damage). 8.20b). New insights on the large scale impacts on tropical cyclogenesis include clarification of the positive role of shear in the baroclinic development of subtropical precursor disturbances and the basin-wide increase in convective organization through the evolution of the intraseasonal Madden-Julian Oscillation (MJO).84,85. While tropical cyclones are common in most of the global tropics, the western North Pacific is the only basin in which they have been observed in every month of the year (Fig. The Cyclone Phase Space (CPS)35 is a diagnostic that utilizes the thermal wind to document the structure of meso-synoptic cyclones concisely. Stages of development of a tropical cyclone* - ResearchGate Finally, changes in storm structure associated with landfall are briefly reviewed. Klotzbach, P. J., W. M. Gray, 2006: Causes of the unusually destructive 2004 Atlantic basin hurricane season. For example, a storm that evolves as described above will be reclassified as "extratropical" by the US National Hurricane Center with no requirement for reintensification. Where associated damage is provided it refers to the expected damage in the maximum wind zone. The seasonal cycle evident here emphasizes the importance of considering the environment in the region and time of tropical storm activity when deducing likely ET. The reasons for the slope of constant absolute angular momentum surfaces in a tropical cyclone and the link to the eyewall structure are discussed in Box 86. 8.14. Fig. It is also the region with the largest number of intense tropical cyclones (orange through red tracks); Tropical cyclones in the western North Pacific and the North Atlantic can have tracks that extend to very high latitudes. The rapid forward speed, large area of gale force winds, intense asymmetric precipitation zone, and potential for extreme ocean waves associated with ET events (Section 8.8.1) make these challenging systems to forecast.