methods for identifying severe thunderstorms by radar: a guide and bibliography1

Donaldson, Ralph J.

doi:10.1175/1520-0477-46.4.174

Cited by 13 publications

(5 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…on the maximum value of the equivalent radar reflectivity factor and its vertical distribution. Geotis [1963], Donaldson [1965], and Changnon and Staggs [1970] showed that the first echoes are higher in hailstorms than in ordinary convective showers and that the associated echoes last longer. Attempts to classify the vertical profiles of reflectivity are continuing, particularly in eastern Europe [e.g., Brylev et al, 1986;Dombai, 1986].…”

Section: Hail Early Work On Hail Detection Concentratedmentioning

confidence: 99%

Nowcasting of precipitation systems

Browning¹,

Collier²

1989

Reviews of Geophysics

View full text Add to dashboard Cite

Digital remotely sensed observations of the atmosphere, particularly from radars and satellites, have become increasingly available over the last 15 years. Together with developments in computer technology this has stimulated the design and operation of a variety of systems to exploit these data in weather forecasting. Growing awareness of the importance of detailed site specific weather information and forecasts from zero to a few hours ahead has led to the emergence of a particular kind of forecasting called nowcasting which depends on the exceptionally detailed knowledge of the current pattern of weather that remote sensing can provide. This type of weather forecasting is reviewed, with emphasis on the measurement and extrapolation up to about 2 hours ahead of fields of various weather parameters, especially rainfall. Trends in the design of nowcasting systems are discussed, and potential benefits summarized. tion of the weather, have been available to forecasters in real time and in a digital form amenable to manipulation. Although the preparation of forecasts by extrapolating the observed fields might be regarded as a simple extension of what forecasters have done for generations, limitations in observing capability and understanding of mesoscale phenomena, together with the practical difficulties of handling vast quantifies of data quickly, make this a challenging task in practice.Since extrapolation is the basis of nowcasting systems, the quality of the resulting forecasts depends upon the time ahead for which linear extrapolation is valid. This varies for different weather systems as shown in Table 1. Frontal rainbands, for example, persist for many hours. However, severe weather caused by individual convective systems is short-lived, and linear extrapolation on its own is unlikely to provide good forecasts beyond an hour or so. The larger-scale systems with greater persistence, such as fronts, often act as the trigger for the smaller convective Published in 1989 by the American Geophysical Union. ß 345 ß Reviews of Geophysics, 27, 3 / August 1989 pages 345-370 Paper number 89RG01134 346 ß Browning and Collier: NOWCASTING OF PRECIPITATION SYSTEMS 27, 3 / REVIEWS OF GEOPHYSICS storm/blizzard High wind gusts 5-30 min very limited accompanying shallow showers Hurricane many hours fair Frontal passage many hours fair to good After Zipser [ 1983]. (Part of this table is from Doswell [ 1986].) 27, 3 /REVIEWS OF GEOPHYSICS Browning and Collier: NOWCASTING OF PRECIPITATION SYSTEMS ß 347 when and where it will be triggered, unless there is some well-def'med topographical forcing, for example. We shall not discuss the nonlinear methods further in this review; rather we concentrate on the conceptually simple linear nowcasting techniques that have been developed to characterize, track, and extrapolate the motion of existing weather features detected by mdars and satellite. At present, nowcasting systems in several countries are providing data for severe weather warning, hydrological forecasting, snow clearance on roa...

show abstract

Section: Hail Early Work On Hail Detection Concentratedmentioning

confidence: 99%

Nowcasting of precipitation systems

Browning¹,

Collier²

1989

Reviews of Geophysics

View full text Add to dashboard Cite

show abstract

“…The quality of results was investigated, after averaging to 6 hr resolution to match the limitations of the wind data, using the simple Critical Success Index (CSI), and related parameter of False Alarm Index (FAI) and Failure Index (FI) (Donaldson 1965). These parameters are a measure of a forecast scheme's ability to predict when rainfall occurs rather than how much rain falls, and are defined as follows: The Critical Success Index Threshold (CSIt) was set to 0.4 mm/hr and its optimisation is discussed along with the other parameters in section 2.2.…”

Section: Discussionmentioning

confidence: 99%

The role of synoptic cloud in orographic rainfall in the Southern Alps of New Zealand

Purdy

Austin

2003

Meteorological Applications

View full text Add to dashboard Cite

“…Many of these radar warning techniques are well documented (Burgess and Lemon, 1990;Donaldson, 1961;Donaldson, 1965;Doswell, 1985;Forbes, 1981). The warning process is complex; it is described more fully in the next section.…”

Section: Z Compositementioning

confidence: 99%

“…Constant Altitude Plan Position Indicator maps (CAPPI) (Marshall, 1957) were developed at McGill University to overcome ground clutter problems. In the past, the significant correlation between strong radar echoes and severe weather were used to issue warnings (Marois, 1977;Lemon, 1977;Donaldson, 1961Donaldson, , 1965. Now, mid and low level CAPPI's are used at the Quebec Weather Centre, to facilitate the identification of the thunderstorm overhang.…”

Section: Technology a Introductionmentioning

confidence: 99%