A WSR-88D Approach to Waterspout Forecasting
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Art Directable Tornadoes
ART DIRECTABLE TORNADOES A Thesis by RAVINDRA DWIVEDI Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 2011 Major Subject: Visualization Art Directable Tornadoes Copyright 2011 Ravindra Dwivedi ART DIRECTABLE TORNADOES A Thesis by RAVINDRA DWIVEDI Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved by: Chair of Committee, Vinod Srinivasan Committee Members, John Keyser Wei Yan Head of Department, Tim McLaughlin May 2011 Major Subject: Visualization iii ABSTRACT Art Directable Tornadoes. (May 2011) Ravindra Dwivedi, B.E., Rajiv Gandhi Proudyogiki Vishwavidyalaya Chair of Advisory Committee: Dr. Vinod Srinivasan Tornado simulations in the visual effects industry have always been an interesting problem. Developing tools to provide more control over such effects is an important and challenging task. Current methods to achieve these effects use either particle systems or fluid simulation. Particle systems give a lot of control over the simulation but do not take into account the fluid characteristics of tornadoes. The other method which involves fluid simulation models the fluid behavior accurately but does not give control over the simulation. In this thesis, a novel method to model tornado behavior is presented. A tool based on this method was also created. The method proposed in this thesis uses a hybrid approach that combines the flexibility of particle systems while producing interesting swirling motions inherent in the fluids. The main focus of the research is on providing easy-to-use controls for art directors to help them achieve the desired look of the simulation effectively. -
Employing the WSR-88D for Waterspout Forecasting
Employing the WSR-88D for Waterspout Forecasting Scott M. Spratt LT (jg) Barry K. Choy, NOAA Corps National Weather Service Melbourne, Florida 1. Introduction Waterspouts and weak coastal tornadoes or "landspouts" (hereafter referred to collectively as "spouts") account for much of Florida's severe weather during the "wet season" (Schmocker et al. 1990). The Melbourne NEXRAD Weather Service Office (NWSO) County Warning Area (CWA) includes 160 miles of coastline along the east central Florida peninsula. Within this area, spouts are most frequent from June through September (Fig. 1). In the past, warnings were issued for spouts only after reports of visual sightings were received. This delay was likely due to the seemingly benign atmospheric conditions in which spouts develop, combined with a lack of pronounced severe weather signatures on conventional radars. However, recent research utilizing the NWSO MLB WSR- 88D may now help forecasters warn for spouts prior to receiving visual reports. A preliminary forecast strategy was developed based on post analyses of archived WSR- 88D products and regional upper-air data from reported spout days (Choy and Spratt 1994). This strategy has proved useful by providing additional lead time for spout events. This paper will identify specific atmospheric conditions which have been observed to precede spout generations along the east central Florida coast. A unique WSR-88D Routine Product Set (RPS) list will be shown which can be implemented once these conditions become satisfied. Finally, case studies of two recent events will be illustrated to help familiarize WSR-88D users with the environmental conditions and radar signatures often evident prior to and during spout events. -
Central Region Technical Attachment 95-08 Examination of an Apparent
CRH SSD APRIL 1995 CENTRAL REGION TECHNICAL ATTACHMENT 95-08 EXAMINATION OF AN APPARENT LANDSPOUT IN THE EASTERN BLACK HILLS OF WESTERN SOUTH DAKOTA David L. Hintz1 and Matthew J. Bunkers National Weather Service Office Rapid City, South Dakota 1. Abstract On June 29, 1994, an apparent landspout occurred in the Black Hills of South Dakota. This landspout exhibited most of the features characteristic of traditional landspouts documented in eastern Colorado. The landspout lasted 3 to 8 minutes, had a width of less than 20 m and a path of 1 to 3 km, produced estimated wind speeds of Fl intensity (33 to 50 m s1), and emanated from a towering cumulus (TCU) cloud located along a quasi-stationary convergencq/cyclonic shear zone. No radar echo was observed with this event; however, a supercell thunderstorm was located 80-100 km to the east. National Weather Service meteorologists surveyed the “very localized” damage area and ruled out the possibility of the landspout being related to microburst, gustnado, or dust devil activity, as winds away from the landspout were less than 3 m s1. The landspout apparently “detached” from the parent TCU and damaged a farm which resulted in $1,000 dollars in expenses. 2. Introduction During the late 1980’s and early 1990’s researchers documented a phe nomenon with subtle differences from traditional tornadoes and waterspouts, herein referred to as the landspout (Seargent 1994; Brady and Szoke 1988, 1989; Bluestein 1985). The term “landspout” was actually coined by Bluestein (I985)(in the formal literature) when he observed this type of vortex along an Oklahoma squall line. -
Doppler Radar Observations of Anticyclonic Tornadoes in Cyclonically Rotating, Right-Moving Supercells
APRIL 2016 B L U E S T E I N E T A L . 1591 Doppler Radar Observations of Anticyclonic Tornadoes in Cyclonically Rotating, Right-Moving Supercells HOWARD B. BLUESTEIN School of Meteorology, University of Oklahoma, Norman, Oklahoma MICHAEL M. FRENCH School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, New York JEFFREY C. SNYDER Cooperative Institute for Mesoscale Meteorological Studies, University of Oklahoma, and NOAA/OAR National Severe Storms Laboratory, Norman, Oklahoma JANA B. HOUSER Department of Geography, Ohio University, Athens, Ohio (Manuscript received 31 August 2015, in final form 27 January 2016) ABSTRACT Supercells dominated by mesocyclones, which tend to propagate to the right of the tropospheric pressure- weighted mean wind, on rare occasions produce anticyclonic tornadoes at the trailing end of the rear-flank gust front. More frequently, mesoanticyclones are found at this location, most of which do not spawn any tornadoes. In this paper, four cases are discussed in which the formation of anticyclonic tornadoes was documented in the plains by mobile or fixed-site Doppler radars. These brief case studies include the analysis of Doppler radar data for tornadoes at the following dates and locations: 1) 24 April 2006, near El Reno, Oklahoma; 2) 23 May 2008, near Ellis, Kansas; 3) 18 March 2012, near Willow, Oklahoma; and 4) 31 May 2013, near El Reno, Oklahoma. Three of these tornadoes were also documented photographically. In all of these cases, a strong mesocyclone (i.e., vortex signature characterized by azimuthal shear in excess of ;5 3 2 2 2 10 3 s 1 or a 20 m s 1 change in Doppler velocity over 5 km) or tornado was observed ;10 km away from the anticyclonic tornado. -
Storm Spotting – Solidifying the Basics PROFESSOR PAUL SIRVATKA COLLEGE of DUPAGE METEOROLOGY Focus on Anticipating and Spotting
Storm Spotting – Solidifying the Basics PROFESSOR PAUL SIRVATKA COLLEGE OF DUPAGE METEOROLOGY HTTP://WEATHER.COD.EDU Focus on Anticipating and Spotting • What do you look for? • What will you actually see? • Can you identify what is going on with the storm? Is Gilbert married? Hmmmmm….rumor has it….. Its all about the updraft! Not that easy! • Various types of storms and storm structures. • A tornado is a “big sucky • Obscuration of important thing” and underneath the features make spotting updraft is where it forms. difficult. • So find the updraft! • The closer you are to a storm the more difficult it becomes to make these identifications. Conceptual models Reality is much harder. Basic Conceptual Model Sometimes its easy! North Central Illinois, 2-28-17 (Courtesy of Matt Piechota) Other times, not so much. Reality usually is far more complicated than our perfect pictures Rain Free Base Dusty Outflow More like reality SCUD Scattered Cumulus Under Deck Sigh...wall clouds! • Wall clouds help spotters identify where the updraft of a storm is • Wall clouds may or may not be present with tornadic storms • Wall clouds may be seen with any storm with an updraft • Wall clouds may or may not be rotating • Wall clouds may or may not result in tornadoes • Wall clouds should not be reported unless there is strong and easily observable rotation noted • When a clear slot is observed, a well written or transmitted report should say as much Characteristics of a Tornadic Wall Cloud • Surface-based inflow • Rapid vertical motion (scud-sucking) • Persistent • Persistent rotation Clear Slot • The key, however, is the development of a clear slot Prof. -
Chapter 3 Mesoscale Processes and Severe Convective Weather
CHAPTER 3 JOHNSON AND MAPES Chapter 3 Mesoscale Processes and Severe Convective Weather RICHARD H. JOHNSON Department of Atmospheric Science. Colorado State University, Fort Collins, Colorado BRIAN E. MAPES CIRESICDC, University of Colorado, Boulder, Colorado REVIEW PANEL: David B. Parsons (Chair), K. Emanuel, J. M. Fritsch, M. Weisman, D.-L. Zhang 3.1. Introduction tion, mesoscale phenomena occur on horizontal scales between ten and several hundred kilometers. This Severe convective weather events-tornadoes, hail range generally encompasses motions for which both storms, high winds, flash floods-are inherently mesoscale ageostrophic advections and Coriolis effects are im phenomena. While the large-scale flow establishes envi portant (Emanuel 1986). In general, we apply such a ronmental conditions favorable for severe weather, pro definition here; however, strict application is difficult cesses on the mesoscale initiate such storms, affect their since so many mesoscale phenomena are "multiscale." evolution, and influence their environment. A rich variety For example, a -100-km-Iong gust front can be less of mesocale processes are involved in severe weather, than -1 km across. The triggering of a storm by the ranging from environmental preconditioning to storm initi collision of gust fronts can actually occur on a ation to feedback of convection on the environment. In the -lOO-m scale (the microscale). Nevertheless, we will space available, it is not possible to treat all of these treat this overall process (and others similar to it) as processes in detail. Rather, we will introduce s~veral mesoscale since gust fronts are generally regarded as general classifications of mesoscale processes relatmg to mesoscale phenomena. -
Presentation
5.4 A SUMMARY OF DATA COLLECTED DURING VORTEX2 BY MWR-05XP/TWOLF, UMASS X-POL, AND THE UMASS W-BAND RADAR Howard B. Bluestein*, M. M. French, J. B. Houser, J. C. Snyder, R. L. Tanamachi School of Meteorology, University of Oklahoma, Norman I. PopStefanija and C. Baldi ProSensing, Inc., Amherst, Massachusetts G. D. Emmitt Simpson Weather Associates, Charlottesville, Virginia V. Venkatesh, K. Orzel, and S. J. Frasier Microwave Remote Sensing Laboratory, University of Massachusetts, Amherst R. T. Bluth CIRPAS, Naval Postgraduate School, Monterey, California 1. INTRODUCTION During VORTEX2, three scanning, mobile, truck-mounted Doppler radars and a mobile, scanning Doppler lidar were used in the field by a group of faculty and graduate students from the University of Oklahoma (OU), supported by personnel from the institutions given above. These platforms were part of the VORTEX2 armada. A scout car from OU assisted with field operations. The U. Mass. W-band radar (Fig. 1) (e.g., Bluestein et al. 2007a) has been used since 1993. It has a half-power beamwidth of 0 0.18 and is used mainly to probe tornadoes Figure 1. U. Mass. W-band radar probing a at high spatial resolution, near the ground, tornado in Goshen County, Wyoming on 5 June from a range of 10 - 15 km or less. 2009. © R. Tanamachi The U. Mass. X-Pol radar (Fig. 2) is an X- band, polarimetric radar, whose antenna has identify polarimetric signatures in supercells 0 a half-power beamwidth of 1.25 . It has (Snyder et al. 2010). been used since 2001 without Doppler or The MWR-05XP (Fig. -
Weather - Tornadoes
Ducksters Reading- Tornadoes Weather - Tornadoes Tornadoes are one of the most violent and powerful types of weather. They consist of a very fast rotating column of air that usually forms a funnel shape. They can be very dangerous as their high speed winds can break apart buildings, knock down trees, and even toss cars into the air. How do tornadoes form? When we talk about tornadoes, we are usually talking about large tornadoes that occur during thunderstorms. These types of tornadoes form from very tall thunderstorm clouds called cumulonimbus clouds. However, it takes more than just a thunderstorm to cause a tornado. Other conditions must occur for a tornado to form. The typical steps for the formation of a tornado are as follows: 1. A large thunderstorm occurs in a cumulonimbus cloud 2. A change in wind direction and wind speed at high altitudes causes the air to swirl horizontally 3. Rising air from the ground pushes up on the swirling air and tips it over 4. The funnel of swirling air begins to suck up more warm air from the ground 5. The funnel grows longer and stretches toward the ground 6. When the funnel touches the ground it becomes a tornado Characteristics of a Tornado Shape - Tornadoes typically look like a narrow funnel reaching from the clouds down to the ground. Sometimes giant tornadoes can look more like a wedge. Size - Tornadoes can vary widely in size. A typical tornado in the United States is around 500 feet across, but some may be as narrow as just a few feet across or nearly two miles wide. -
Hurricanes and Tropical Storms Location and Extent of All • Severe Thunderstorms Natural Hazards That Can Affect the Jurisdiction
HAZARD I DENTIFICATION The United States and its communities are vulnerable to a wide array of natural hazards that threaten life and property. These hazards include, in no particular order: • Drought 44 CFR Requirement • Extreme Temperatures Part 201.6(c)(2)(i): The risk • Flood assessment shall include a description of the type, • Hurricanes and Tropical Storms location and extent of all • Severe Thunderstorms natural hazards that can affect the jurisdiction. The plan • Tornadoes shall include information on • Wildfire previous occurrences of hazard events and on the • Winter Storms probability of future hazard • Erosion events. • Earthquakes • Sinkholes • Landslides • Dam/Levee Failure Some of these hazards are interrelated (i.e., hurricanes can cause flooding and tornadoes), and some consist of hazardous elements that are not listed separately (i.e., severe thunderstorms can cause lightning; hurricanes can cause coastal erosion). It should also be noted that some hazards, such as severe winter storms, may impact a large area yet cause little damage, while other hazards, such as a tornado, may impact a small area yet cause extensive damage. This section of the Plan provides a general description for each of the hazards listed above along with their hazardous elements, written from a national perspective. Section 4: Page 2 H AZARD I DENTIFICATION N ORTHERN V IRGINIA R EGIONAL H AZARD M ITIGATION P LAN Drought Drought is a natural climatic condition caused by an extended period of limited rainfall beyond that which occurs naturally in a broad geographic area. High temperatures, high winds, and low humidity can worsen drought conditions, and can make areas more susceptible to wildfire. -
Tornadoes and Waterspouts in Catalonia (1950–2009)
Nat. Hazards Earth Syst. Sci., 11, 1875–1883, 2011 www.nat-hazards-earth-syst-sci.net/11/1875/2011/ Natural Hazards doi:10.5194/nhess-11-1875-2011 and Earth © Author(s) 2011. CC Attribution 3.0 License. System Sciences Tornadoes and waterspouts in Catalonia (1950–2009) M. Gaya`1, M.-C. Llasat2, and J. Arus´ 3 1Agencia Estatal de Meteorolog´ıa, Delegacio´ Territorial a les Illes Balears, Palma, Spain 2Department of Astronomy and Meteorology, University of Barcelona, Spain 3Agencia Estatal de Meteorolog´ıa, Delegacio´ Territorial a Catalunya, Barcelona, Spain Received: 28 September 2010 – Revised: 8 May 2011 – Accepted: 12 June 2011 – Published: 8 July 2011 Abstract. This paper presents a preliminary climatology of be caused by the interest of its population in unusual phe- tornadoes and waterspouts in Catalonia (NE Iberian Penin- nomena, such as tornadoes. Indeed, this Spanish Mediter- sula). A database spanning 60 yr (1950–2009) has been de- ranean region is frequently affected by heavy rains and flood- veloped on the basis of information collected from various ing, strong winds and sea storms and forest fires (Pinol˜ et al., sources such as weather reports, insurance companies, news- 1998; Camuffo et al., 2000; Llasat, 2009). However, in spite papers and damage surveys. This database has been sub- of tornadoes and waterspouts being less frequent and the area jected to a rigorous validation process, and the climatology affected much smaller, the relative impact in the media (mea- describes its main features: timing, spatial pattern, and trends sured by the number of news items and the ratio between in the tornado and waterspout distribution. -
FLORIDA HAZARDOUS WEATHER by DAY (To 1994) NOVEMBER 1-3 1956
FLORIDA HAZARDOUS WEATHER BY DAY (to 1994) NOVEMBER 1-3 1956 - entire east coast - A Tropical Depression that moved north out of Cuba on October 31st and made a loop east of Florida on the 1st through 3rd brought high tides and heavy surf to much of east Florida. Extensive property damage and beach erosion was reported from Jacksonville to Neptune Beach. Many beach roads and oceanfront properties were undermined at various points by pounding surf. 2 1971 -1327 - E. Sarasota - Funnel cloud reported. 3 1968 - 1755 - Escambia Co. - Tornado crossed the extreme northwest part of Escambia Co. Florida doing little damage, however 18 people were injured as homes and trailers were destroyed across the border in Saraland, AL. 3 1987 - 0224 - Monroe Co., Key West - A thunderstorm wind gust of 55 knots was reported at Boca Chica Naval Air Station. 4 1935 - south Florida - The so-called "Yankee Hurricane" struck Dade County from the northeast. Winds were 75 mph in Miami with a storm surge of 6 feet. The storm exiting into the Gulf of Mexico on the lower southwest coast north of the Keys. It recurved back toward Florida on the 6th and dissipated off Tampa Bay on the 8th. Nineteen deaths were attributed to this storm. 4 1988 - 0115 - Lee Co., Fort Myers - Tornado destroyed two homes, severely damaged seven, and damaged 109 others to a lesser degree. Eight cars and three boats were also damaged. About 80 Royal Palms were blown down along a scenic street. 4 1996 - 1620 - Palm Beach County, Palm Beach - one person drowned in a rip current. -
Tornadic Waterspouts Impacts on Coastal Australia
18th Australasian Wind Engineering Society Workshop McLaren Vale, South Australia 6-8 July 2016 Tornadic Waterspout Impacts on Coastal Australia M.J. Glanville1, C.J. Rohr1 and J.D. Holmes1 1Cermak Peterka Petersen Pty Ltd, 2/500 Princes Highway, St Peters, NSW, 2044 Abstract documented by Glanville & Quinn (2010), at Kiama in 2013, and at Kurnell in 2015. Surveyed damage using the Enhanced Fujita Scale is presented for a recent tornadic waterspout event at Kurnell in NSW. Kurnell, NSW experienced tornadic supercell winds on 16 December 2015 as described by Krupar, Mason and Glanville Recent tornadic events at Kurnell, Kiama and Lennox Head in (2016). The supercell originally formed near Port Kembla, NSW coastal New South Wales formed either wholly or partly approximately 60km to the southwest. For the next two hours, the offshore. It is proposed that a warm, moist layer of air at the sea supercell continued to evolve as it tracked north-northeast along surface creates more unstable atmospheric conditions than would the coast of NSW toward Kurnell. Rapid intensification was an approaching supercell path over land, and hence a greater observed at 9:19am; a clear hook-echo is also evident in rain propensity to generate a tornadic event. radar reflectivity scans signifying localised rotation. -1 Measured and observed wind velocities in the vicinity of 60 ms It is proposed the supercell coastal path line itself contributed to associated with the observed tornadic waterspouts are the formation of a tornadic waterspout at Kurnell. A warm, moist considerably higher in magnitude than the basic wind speed layer of air at the sea surface creating more unstable atmospheric presented in AS1170.2 for an estimated return period of 2000 conditions than would an approaching supercell path over land.