As widespread deserts is located in west and southwest of Iran plateau, dust storms form due to west andsouthwest systems over Syria or Iraq as well as Arabian Peninsula. These systems severely affect west and southwestregions. Sometimes the fine dusts transmit to central, north east, and east regions. In this study for investigating dustysynoptical patterns, meteorological data at 5 synoptic s...

During the 24-hour period ending 1230 GMT May 13, 1957 moderate to heavy convective-type rain occurrecl over a large portion of north central Texas. In consideration of the type of prec.ipitation, amounts were not unusually large, ranging from 1 to 5 inches (fig. 1). However, the most interesting feature was that the rainfall area was well organized and locat,ed in an area where the surface is...

An updated climatology of EF1+ (Enhanced Fujita category 1 or stronger) tornadoes in Italy (445 events the period 1990–2021) confirms that central Tyrrhenian (CT) and southeastern (SE) regions Italian peninsula represent two areas most affected by Mediterranean. We performed a comparative analysis between these hotspots, examining large-scale atmospheric features associated to tornado occurrenc...

5 Multiscale analysis is used to derive two sets of coupled models, each based on the same distinguished limit, to represent the interaction of the midlatitude oceanic synoptic scale — where coherent features such as jets and rings form — and the mesoscale, defined by the internal deformation scale. The synoptic scale and mesoscale overlap at low and mid latitudes, and are hence synonymous in m...

The conceptual model of a classical surface-based cold front consists of a sharp temperature decrease coincident with a pressure trough and a distinct wind shift at the surface. Many cold fronts, however, do not conform to this model—time series at a single surface station may possess a pressure trough and wind shift in the warm air preceding the cold front (hereafter called a prefrontal trough...

The development and motion of fronts associated with lee-side troughs on large mountain barriers has been investigated. These fronts differ from ordinary cold fronts in their horizontal temperature field, which is characterized by a sinusoidal thermal ridge. The thermal ridge intensifies, while remaining stationary with respect to the mountains, and moves eastward upon the approach of a Pacific...