heavy precipitation plays a significant role in arid and semi-arid regions of iran. in order to understand the effect of blocking high system on rainfalls in northwest iran during 25 - 28 october 2008, meteorological conditions including pressure, wind fields and temperature at multiple levels of the atmosphere were analyzed. sea level pressure, the 1000-500 hpa thickness, perceptible water, re...

The meteorological conditions during the period of spring transition over the Middle East and the Persian Gulf and adjacent land area is investigated. Monthly and seasonal variations of large-scale atmospheric patterns and wind aloft features at different levels were drawn from data collected from the National Centers for Environmental Prediction and National Center for Atmospheric Researches. ...

the moisture flux convergence (mfc) and relative humidity in dusty days at different times and levels over the alvand mountain was investigated. the required basic data for the years 2009-2012, including relative humidity, visibility and synoptic codes, were gathered from hamadan synoptic station, while sea level pressure, uwind, vwind and specific humidity data were gathered from ncer/ncar sit...

introduction subtropical high pressure is one of the main elements of the general circulation of the atmosphere. annual motion of the circulation plays an important role in movement path of pressure systems and westerlies. hence, large parts of the planet are affected directly and indirectly by this system. sometimes the high pressure called the subtropical high pressure belt. it’s shown as sev...

summer heat and drought conditions, especially in the southern half of iran's air sovereignty is recognized. in order to investigate the synoptic conditions - scanning the effect of unusual rain event for summer 12 to 6 september 2008 (22-16 september 1387) in the southern zagros range, environmental approach to sightseeing and daily statistics recording station 270 days of rain detected. ...