A Summary of Some Radar Thunderstorm Observations*

Brooks, H. B.

doi:10.1175/1520-0477-27.10.557

Cited by 21 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The method involves three main vectors, called cell (C), system (S) and propagation (P) vectors (refer to Figure 1 in Corfidi et al [34]), which satisfy the relationship P = S − C. Based on observational analysis, Corfidi et al [34] found that cells tend to move with the mean 850-300-hPa wind with respect to speed and direction. This was consistent with the observational studies of Brooks [39] and Byers and Battan [40]. On the other hand, the magnitude and direction of the propagation vector P are assumed to be equal and opposite to those of the LLJ, and the LLJ vector is defined as the maximum wind vector below 3.5 km.…”

Section: Methodssupporting

confidence: 77%

Characteristics and Formation of a Synoptic Situation Causing Sudden Turning of Mesoscale Convective Systems over South China

2019

View full text Add to dashboard Cite

The characteristics and formation of a synoptic situation that causes a sudden turning motion of warm-sector mesoscale convective systems (MCSs) over South China are described, based on the collection and investigation of associated cases during April–June 2011–2017 using high-resolution observational data and ERA (ECMWF Re-Analysis)-Interim data. The results show that the blocking of a marked low-level high over eastern China (eastern high) on a strengthening low-level trough over southwestern China (southwestern trough) results in significant enhancement of southerly winds ahead of the trough, which produces a strong southeastward vertical wind shear at low levels near western Guangdong province. This low-level vertical wind shear results in sudden southeastward turning motion for the warm-sector MCSs entering into Guangdong province from Guangxi province. The formation of the eastern high is mainly attributable to the strong cyclonic wind anomaly over the northwestern Pacific Ocean, which continuously brings cold air from higher latitudes to eastern China, where high synoptic-scale transient anomaly of geopotential height (SSTA-GH) forms. This cyclonic wind anomaly is induced by a low SSTA-GH, which travels from the north and south sides of the Tibetan Plateau to the northwestern Pacific Ocean and develops significantly as a result of a strong upper-level low SSTA-GH coupling with it or approaching it. On the other hand, the high SSTA-GH over eastern China blocks the eastward extension of the low SSTA-GH originating from the Tibetan Plateau. Consequently, this low SSTA-GH turns to extend or move southeastward/southward to southwestern China, leading to intensification of the southwestern trough.

show abstract

Section: Methodssupporting

confidence: 77%

Characteristics and Formation of a Synoptic Situation Causing Sudden Turning of Mesoscale Convective Systems over South China

2019

View full text Add to dashboard Cite

show abstract

“…UMEROUS studies have been made of the movements of thunderstorms in relation to winds aloft. Discussions and summaries of the principal results may be found in articles by H. B. Brooks [2], the U. S. Weather Bureau [10], and Ligda and Mayhew [6]. As noted in THE THUNDERSTORM, prior to the advent of radar it was not possible to obtain reliable in- 1 Based on a thesis submitted by Captain Katz, in partial fulfillment of the requirements for the degree of Master of Science.…”

mentioning

confidence: 99%

Movement of Large Convective Rainstorms in Relation to Winds Aloft

Newton

Katz

1958

Bulletin of the American Meteorological Society

View full text Add to dashboard Cite

By means of hourly rainfall data from the Hydroclimatic Network, the motions of large rainstorms, of the kind associated with squall lines, are examined in relation to the winds aloft. Very little correlation is found between the speed of movement of the rainstorms and the wind speed at any level, although the fastest moving storms were associated with strong winds aloft. Significant correlation is found between direction of motion of rainstorms, and wind direction at 700 mb or higher levels. On the average, the rainstorms move with an appreciable component toward right of the wind direction. The difference between these results, and those from other studies based on small precipitation areas, is ascribed to propagation. The mechanism involved is discussed briefly.

show abstract

“…This cannot be true when instantaneous wind data are not available since significant differences were found from the comparison with the Meteorological Bulletin maps (see Table 3). It has long been accepted that thunderstorms move, on average, with the wind at approximately the 700 hPa level, [ Brooks , 1946; Holland , 1967]. As evidenced in the past by Humphreys [1940], it would be at these heights where the strata containing most of the cumulonimbus extend.…”

Section: Movement Of the Rain Cellsmentioning

confidence: 99%

Experimental analysis of microscale rain cells and their dynamic evolution

et al. 2005

View full text Add to dashboard Cite

This paper presents a detailed space‐time analysis of rainfall rate using two dense networks of rain gauges covering two microscale areas of some 100 km2 each and located in two distinct climatic areas in the United Kingdom and Spain. The study has been carried out with the main objective of addressing dynamic fade mitigation techniques and scatter interference problems in terrestrial and satellite communication systems. The two databases, using a total of 49 and 23 rain gauges, respectively, are described, and the continuous interpolated field used for the subsequent analyses is explained in detail. The suitability of the networks in terms of density, correlation distance, and fractal dimension are briefly addressed. A to‐scale comparison grid of the networks is also given. It has been found that when the maximum intensity reached during a rain event surpasses a certain threshold, different for each of the two areas, rainfall rates exhibit a spatial structure in the form of closed contours of thresholds referred to as cells. In statistical terms, the most probable diameter found is about 3.5 km, and distributions are presented. They are similar for the two sites but not so for the maxima reached inside the cells. Using cross‐correlation techniques, displacement and velocities are analyzed in detail. Cells “zigzag” around a dominant trend because of the global cloud movements (driven by winds at heights of about 700 hPa). Local topography strongly affects local behavior. Analytical approximations to the experimental statistical distributions and selected histograms of the results are presented.

show abstract

A Summary of Some Radar Thunderstorm Observations*

Abstract: Direct observation of rain areas by radar yields new information on thunderstorm characteristics and behavior. A statistical summary of characteristics of 300 showers observed by radar at Spring Lake, N. J., June–Aug. 1945, is given.

Cited by 21 publications

References 0 publications

Characteristics and Formation of a Synoptic Situation Causing Sudden Turning of Mesoscale Convective Systems over South China

Characteristics and Formation of a Synoptic Situation Causing Sudden Turning of Mesoscale Convective Systems over South China

Movement of Large Convective Rainstorms in Relation to Winds Aloft

Experimental analysis of microscale rain cells and their dynamic evolution

Contact Info

Product

Resources

About