East Coast Storm Research Articles

Extraordinary sequence of severe weather events in the late-nineteenth century

Between 1883 and 1898, 24 intense tropical cyclones and extra tropical cyclones directly impacted on the southern Queensland and northern New South Wales coasts, with at least 200 fatalities in what was then a sparsely populated area. These events also caused record floods and rainfall, for example Brisbane City experienced its two largest ever floods over this period and Brisbane City set a 24-h rainfall record that still stands today. Additionally, a 24-h rainfall total of 907 mm occurred in a tributary of the upper Brisbane River resulting in a 15-m wall of water advancing down the river. Recent studies have shown that this part of Australia incurs the largest weather-related insurance losses. A major focus in this study is the seas these storms generated, leading to the loss of many marine craft and changes these waves brought to coastal areas. As a famous example of coastal erosion near Brisbane, the continual impacts from large waves caused a channel to form through Stradbroke Island to the open ocean forming two separate islands. Details of how this channel formed are described in relation to the storms. A climatology study of 239 Australian east coast storms that caused severe ocean damage between Brisbane and the Victorian border over the period between 1876 and February 2020 showed that 153 events occurred with a positive Southern Oscillation Index (SOI) trend and 86 events with a negative trend. The most active years were 1893 and 1967, both during positive SOI periods and both dominated by tropical cyclone activity. The 1893 events caused unparalleled floods and strongly contributed to the Jumpinpin breakthrough on Stradbroke Island, and the 1967 event was associated with historical Gold Coast beach erosion causing 9 billion normalised Australian dollars of insurance losses. The study also showed how direct tropical cyclone impacts in the study area decreased markedly following the June 1976 climate shift.

The application of data innovations to geomorphological impact analyses in coastal areas: An East Anglia, UK, case study

Rapidly advancing surveying technologies, capable of generating high resolution bathymetric and topographic data, allow precise measurements of geomorphological change and deformation. This permits great accuracy in the characterisation of volumetric change, sediment and debris flows, accumulations and erosion rates. However, such data can be utilised inadequately by coastal practitioners in their assessments of coastal change, due to a lack of awareness of the appropriate analytical techniques and the potential benefits offered by such data-driven approaches. This was found to be the case for the region of East Anglia, UK, which was analysed in this study. This paper evaluates the application of innovative geomorphological change detection (GCD) techniques for analysis of coastal change. The first half of the paper contains an extensive review of GCD methods and data sources used in previous studies. This leads to the selection and recommendation of an appropriate methodology for calculation of volumetric GCD, which has been subsequently applied and evaluated for 14 case study sites in East Anglia. This has involved combining open source point cloud datasets for broad spatial scales, covering an extended temporal period. The results comprise quantitative estimates of volumetric change for selected locations. This allows estimation of the sediment budgets for each stretch of coastline focused upon, revealing fluctuations in their rates of change. These quantitative results were combined with qualitative outputs, such as visual representations of change and we reveal how combining such methods assists identification of patterns and impacts linked to specific events. The study demonstrates how high-resolution point cloud data, which is now readily available, can be used to better inform coastal management practices, revealing trends, impacts and vulnerability in dynamic coastal regions. The results also indicate heterogeneous impacts of events, such as the 2013 East Coast Storm Surge, across the study area of East Anglia.

Synoptic Characteristics of Surge-Producing Extratropical Cyclones along the Northeast Coast of the United States

AbstractExtratropical cyclones (ETCs) are responsible for most of the large storm-surge events in the northeastern United States. This study uses the ECMWF atmospheric reanalysis of the twentieth century (ERA-20C) and NOAA tide gauge data to examine the local, regional, and large-scale atmospheric circulation accompanying the 100 largest ETC-driven surge events at three locations along the northeastern coast of the United States: Sewells Point (Norfolk), Virginia; the Battery (New York City), New York; and Boston, Massachusetts. Results from a k-means cluster analysis indicate that the largest surges are generated when slowly propagating ETCs encounter a strong anticyclone, which produces a tighter pressure gradient and longer duration of onshore winds. The strength of the anticyclone is evident in the middle and upper troposphere where there are positive 500-hPa geopotential height anomalies overlying the surface anticyclone for the majority of clusters and nearly all of the five biggest surge events. Multiple clusters feature a slower-than-average storm and a strong anticyclone, indicating that various circulation scenarios can produce a large storm surge. This favorable environment for large surge events is influenced by well-known modes of climate variability including El Niño, the Arctic Oscillation (AO), the North Atlantic Oscillation (NAO), and the Pacific–North American (PNA) pattern. ETCs are more likely to produce a large surge during El Niño conditions, which have been shown to enhance the East Coast storm track. At Boston and the Battery, maximum surge occurs preferentially during the positive phase of PNA and the negative phases of AO/NAO.

Interannual Variability of Northern Hemisphere Storm Tracks in Coarse-Gridded Datasets

Extratropical cyclones exert a large socioeconomic impact. It is therefore important to assess their interannual variability. We generate cyclone tracks from the National Center for Environmental Prediction’s Reanalysis I and the European Centre for Medium Range Prediction ERA-40 reanalysis datasets. To investigate the interannual variability of cyclone tracks, we compare the effects of El Niño, the North Atlantic Oscillation (NAO), the Indian Ocean Dipole (IOD), and the Pacific North American Pattern (PNA) on cyclone tracks. Composite analysis shows similar results for the impacts of El Niño, NAO, and the PNA on NH storm tracks. Although it is encouraging, we also found regional differences when comparing reanalysis datasets. The results for the IOD suggested a wave-like alteration of cyclone frequency across the northern US/Canada possibly related to Rossby wave propagation. Partial correlation demonstrates that although El Niño affects cyclone frequency in the North Pacific and along the US east coast, its impact on the North Pacific is accomplished via the PNA. Similarly, the PNA’s impact on US east coast storms is modulated via El Niño. In contrast, the impacts of the NAO extend as far west as the North Pacific and are not influenced by either the PNA or El Niño.

Hurricane Sandy spins up climate discussion

Destructive power of US east-coast storm stems from factors that include — but are not limited to — global warming.

Statistical Differences of Quasigeostrophic Variables, Stability, and Moisture Profiles in North American Storm Tracks

Abstract Three common synoptic storm tracks observed throughout the United States are the Alberta Clipper, the Colorado cyclone, and the East Coast storm. Numerous studies have been performed on individual storm tracks analyzing quasigeostrophic dynamics, stability, and moisture profiles in each. This study evaluated storms in each track to help diagnose patterns and magnitudes of the aforementioned quantities, documenting how they compare from track to track. Six diagnostic variables were computed to facilitate the comparison of the storm tracks: differential geostrophic absolute vorticity advection, temperature advection, Q-vector divergence, mean layer specific humidity, low-level stability, and midlevel stability. A dataset was compiled, consisting of 101 Alberta Clippers, 165 Colorado cyclones, and 159 East Coast cyclones and mean fields were generated for this comparison. Maxima and minima of the 25th and 75th percentiles were generated to diagnose magnitudes and patterns of strong versus weak cyclones and measure their similarities and differences to the mean patterns. Alberta Clippers were found to show the weakest magnitude of quasigeostrophic variables, while East Coast storms had the strongest magnitudes. Alberta Clippers maintained the lowest moisture content through their life cycle as well. However, East Coast storms were the most stable of the three tracks. Typically, correlations between storm tracks were high; suggesting that storm evolution is similar between tracks, in terms of the patterns of diagnostic variables measured. However, significant magnitude differences in the quasigeostrophic variables distinguished the storms in each track.

Climatology and ENSO-Related Variability of North American Extratropical Cyclone Activity

Abstract The climatology and interannual variability of North American extratropical cyclones are examined using 6-hourly sea level pressure data from the NCEP–NCAR reanalysis for the period 1950–2002 and ECMWF 40-yr Re-Analysis (ERA-40) data from 1971 to 2000. The climatology includes an evaluation of the seasonal frequency and intensity of storms as well as an analysis of extreme event intensity. ENSO variability is evaluated by ENSO phase with emphasis on boreal winter. Results show an enhanced East Coast storm track during El Niño as well as an equatorward shift in storm tracks in the North Pacific for storms generated from both the NCEP–NCAR reanalysis and ERA-40 datasets. Observed precipitation close to a storm’s center is used to determine which phase of the ENSO cycle is associated with the most productive storms and where they occur. During El Niño winters, a precipitation maximum is located east of the Appalachians and is associated with an enhanced East Coast storm track. During La Niña winters, the precipitation maximum shifts to the Ohio Valley and is associated with an enhanced Great Lakes storm track. Along the U.S. west coast, there is a precipitation maximum in the Pacific Northwest during La Niña winters, which is due to a storm track west of Washington State.

John Russell (Russ) Mather at the Laboratory of Climatology

John Russell (Russ) Mather joined the group of young aspiring graduate students that C. W. Thornthwaite attracted to his newly formed climatological research operation at Seabrook Farms, New Jersey, in the late 1940s. From the beginning he worked closely with Thornthwaite to develop the Thornthwaite Water Balance concept into an effective climatological tool. He co-authored Thornthwaite's well-known revised statement "The Water Balance" and numerous other publications. He edited the C. W. Thornthwaite Associates' Publications in Climatology and, after Thornthwaite's death in 1963, became president of C. W. Thornthwaite Associates. Four components comprised this consulting operation: not-for-profit scientific research in climatology, water budget climatology, and microclimatology; design and manufacture of instrumentation for micrometeorological research; consulting for industrial and commercial clients in climatology and the climatic water budget; and design and installation of industrial irrigated wastewater disposal systems. As editor of Publications in Climatology, Russ was responsible for documenting all the Laboratory's research activities. Russ produced the multi-volume tabulation "Average Climatic Water Balance Data of the Continents." The great March 1962 coastal storm on the eastern seaboard of the United States provided occasion for writing two papers in which he characterized damaging East Coast storms. He resigned the presidency of C. W. Thornthwaite Associates in 1972 to devote full attention to the University of Delaware Department of Geography, where he had been chairman since 1966.

A Reexamination of the Mechanisms Responsible for Banded Precipitation

Abstract The processes responsible for a banded snowfall region during a December 1997 East Coast storm are examined. Conventional data plus a numerical simulation with the fifth-generation Pennsylvania State University–NCAR Mesoscale Model (MM5) are used. Calculations of slantwise potential area near the bands suggest that the release of conditional symmetric instability played a role in their formation. The location and timing for the appearance of negative moist potential vorticity (MPV) cannot, however, be reconciled with band formation. A balanced MPV model based on the geostrophic momentum approximation is developed. It provided new insights into the mechanisms of MPV generation. A swath of negative balanced MPV now coincides with the snowbands. MPV sources are proposed that are linked to a vigorous mesoscale updraft near the bands. The updraft occurred on the warm, moist side of a zone of midtroposphere frontogenesis. Negative MPV develops through differential ageostrophic transports of geostrophic...

East Coast storm surges provide unique climate record

Coastal storms repeatedly hit the U.S. East Coast, costing many billions of dollars in losses. In 1992 Hurricane Andrew alone caused about $35–40 billion in damage. In addition to property damage, coastal storms are the major contributors to beach and dune erosion, overwash processes, and the opening of tidal inlets on barrier islands. What changes, if any, can we expect in coastal storm activity and intensity as global temperatures rise?

Overview of the 12–14 March 1993 Superstorm

An extratropical cyclone of unusual intensity and areal extent affected much of the Gulf and East Coasts of the United States on 12–14 March 1993. In this paper, the many effects of the storm will be highlighted, including perhaps the most widespread distribution of heavy snowfall of any recent East Coast storm, severe coastal flooding, and an outbreak of 11 confirmed tornadoes. A meteorological description of the storm is also presented, including a synoptic overview and a mesoscale analysis that focuses on the rapid development of the cyclone over the Gulf of Mexico. This is the first part of a three-paper series that also addresses the performance of the operational numerical models and assesses the forecasting decisions made at the National Meteorological Center and National Weather Service local forecast offices in the eastern United States.

The Effect of Gulf Stream-induced Baroclinicity on U.S. East Coast Winter Cyclones

Abstract Midlatitude cyclones develop off the Carolinas during winters and move north producing gale-force winds, ice, and heavy snow. It is believed that boundary-layer and air-sea interaction processes are very important during the development stages of these East Coast storms. The marine boundary layer (MBL) off the mid- Atlantic coastline is highly baroclinic due to the proximity of the Gulf Stream just offshore. Typical horizontal distances between the Wilmington coastline and the western edge of the Gulf Stream vary between 90 and 250 km annually, and this distance can deviate by over 30 km within a single week. While similar weekly Gulf Stream position standard deviations also exist at Cape Hatteras, the average annual distance to the Gulf Stream frontal zone is much smaller off Cape Hatteras, normally ranging between 30 and 100 km. This research investigates the low-level baroclinic conditions present prior to observed storm events. The examination of nine years of data on the Gulf Stream position...

Numerical forecasting of winter coastal storms during CASP: Evaluation of the regional finite‐element model

Abstract As part of the Canadian Atlantic Storms Program (CASP), a meso‐α scale version of the regional finite‐element model was set up for the short‐term forecasting of East Coast storms during the CASP field phase. The main features of the mesoscale model compared with the operational continental version include a 100‐km resolution over a reduced domain, a modified physics package, improved surface and geophysical field analyses, and the refinement of initial moisture analyses using satellite imagery. Field evaluations of the mesoscale and continental models by CASP meteorologists indicated that both models generally underpredicted storm speed and deepening and that the CASP model yielded more accurate storm locations. Mesoscale forecasts of precipitation types and boundary‐layer winds were quite realistic when compared with actual station reports. Objective verification scores for 11 storm cases confirm the better meteorological performance of the mesoscale model. The most striking improvements are fou...

Oceanographic studies during Project GALE

The Genesis of Atlantic Lows Experiment (GALE) was a multi‐institutional project sponsored primarily by the National Science Foundation (NSF), with additional support from the National Oceanographic and Atmospheric Administration (NOAA), the National Aeronautics and Space Administration (NASA), and the Office of Naval Research (ONR). The primary objectives were to describe the airflow, mass, and moisture fields during the evolution of U.S. East Coast winter storms, with special emphasis on mesoscale processes; to understand the physical mechanisms controlling the formation and rapid development of East Coast storms; and to develop and test numerical models for the prediction of East Coast cyclones.

GALE improves snow forecasting

Scientific results from an intensive study of winter storms on the U.S. East Coast last year contributed to improved weather forecasts of two successive snowstorms that virtually closed down Washington, D.C., for several days in January 1987.In the Genesis of Atlantic Lows Experiment (GALE) field project, scientists took detailed measurements simultaneously from the atmosphere and the ocean to study how these features interact at various stages of an East Coast winter storm, according to project director Richard Dirks, who is with the National Center for Atmospheric Research (NCAR) in Boulder, Colo. “It's interesting that we actually had four storms [in the GALE study] that were of similar intensity to the two East Coast storms” in January 1987, Dirks said. “However, last year the temperatures were warmer, and the storm tracks were located somewhat further offshore and therefore did not significantly affect the northeast corridor with heavy snows.”

Albedo of a Dissipating Snow Cover

Abstract Albedos of surfaces covered with 50 cm of fresh dry snow following a major U.S. East Coast storm on 11–12 February 1983 ranged from 0.20 over a mixed coniferous forest to 0.80 over open farmland. As the snow cover dissipated, albedo decreased in a quasi-linear fashion over forests. It dropped rapidly at first, then slowly, over shrubland; while the opposite was observed over farmland. Following the melt, the albedo of snowfree surfaces ranged from 0.07 over a predominantly wet peat field to 0.20 over a field covered with corn stubble and yellow grass. The difference between snow-covered and snowfree albedo was 0.72 over the peaty field and 0.10 over the mixed forest. Visible band (0.28–0.69 μm) reflectivities of snow-covered fields and shrubland were higher than those in the near-infrared (0.69–2.80 μm), whereas the opposite was true over mixed coniferous forests. Visible and near-infrared reflectivities were approximately equal over deciduous forests. Data were collected in a series of low-altit...

The National Meteorological Center's Performance in the Forecasting of a Winter Storm, – February

The worst east coast storm of 1971–72 developed very rapidly and reached maturity at extreme southerly latitudes. To a large degree, the development was forecast more than two days in advance by use of the National Meteorological Center 6-layer primitive equation (P.E.) model. However, the P.E. prognosis contained systematic errors. Most were eliminated by the limited area fine mesh model (LFM) and NMC forecasters. NMC's total performance with the storm was nearly the best possible with the current state-of-the-art. The successful forecast of cyclogenesis led to equally successful forecasts of precipitation quantities, heavy snow, and storm surges, among other things. Examples are presented.

Detailed Analyses of Precipitation Patterns Associated With Mesoscale Features Accompanying United States East Coast Cyclogenesis

Abstract Detailed hourly precipitation patterns are analyzed for two major winter U.S. east coast storms that exhibited considerable mesoscale features. Pronounced spatial and temporal continuity is noted for individual convective rainfalls within the cold air. Such features can also be tracked in the wind and pressure fields. Finally, some thoughts are offered on the possible dynamic significance of organized mesoscale precipitation patterns, along with comments relevant to the forecasting of such patterns.

From Above: A Developing East Coast Storm

From Above: A Developing East Coast Storm

March East Coast Storm

March East Coast Storm