Browsing by Subject "Synoptic meteorology"

Now showing 1 - 3 of 3
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    A mesoscale study of Texas South Plains convective systems
    (Texas Tech University, 1983-05) Solomon, Martin D
    A mesoscale investigation of the properties of four days which had varying degrees of convective activity in the Texas South Plains region has been performed. The four days were classified into categories based on intensity and organization of the convection. The categories had been developed through previous research performed on HIPLEX data sets. Mesoscale analysis techniques, including the time change of potential buoyant energy, lifting condensation level, and lifted index plots, wind and equivalent potential temperature vertical profiles, average sounding plots, and moisture divergence computations, were employed in the search for the distinguishing meteorological characteristics in each case. Synoptic scale observations consisted of National Weather Service (NWS) surface and upper air maps, and Geostationary Operational Environmental Satellite (GOES-EAST) imagery. The results indicate that each classification did have a unique set of properties on the mesoscale. It is also shown that the parameters of 9e, PBE, LCL and wind velocity were superior in explaining the meteorological differences among the categories. Although only a limited number of case studies have been undertaken here, insight has been gained in the understanding of the mesoscale characteristics of convectively driven precipitation events over the Texas South Plains.
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    A study of the relation between surface convergence and convective initiation along the dryline
    (Texas Tech University, 1998-12) Jones, Andrew
    The frequency of shower and thunderstorm development is known to be greater near the dryline than in areas further removed. The dryline is a common feature across New Mexico and West Texas during the springtime and is often associated with severe weather across the region. The exact forcing mechanism that initiates convection along the dryline is not known. Recent studies suggest that localized areas of surface convergence and moisture convergence along the dryline may be the primary initiating mechanism. This thesis is an observational study that compared where convection occurred along the dryline to where areas of localized convergence and moisture convergence existed. Three similar dryline cases were examined. It was found that convection initiated in close proximity to areas of maximum convergence in two out of the three cases.
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    Investigation of the 8 May 1998 event using satellite derived parameters
    (Texas Tech University, 2000-08) Brandt, Richard Raymond
    The dryline has long been studied as a feature along which convection and severe weather occur. It is a narrow region with a strong moisture gradient that results from the advection of two different air masses, namely continental tropical (cT) air with origins in the southwest United States and northern Mexico and maritime tropical (mT) air from the Gulf of Mexico. The surface intercept of these air masses is generally accepted as the dryline location. On 8 May 1998 a dryline formed in conjunction with low pressure that had redeveloped on the lee side of the Rocky Mountains. The system produced numerous storms as it progressed eastward across eastern New Mexico, western and central Texas, and Oklahoma. Severe weather, including hail, strong thunderstorm winds, and several weak tornadoes, were reported with these storms. Some of these events caused major crop and property damage. Data collected by the geostationary satellite, GOES-8, were used to track and analyze the events of 8-9 May 1998 along with surface and upper-air observations and radar data. The GOES-8 imager was placed in Super-Rapid Scanning Operation (SRSO) for this case. Imagery was recorded at 1-minute intervals during certain periods in this scanning mode. Hourly Derived Product Images (DPI's) from the GOES-8 sounder were also utilized. Of the three available DPI's, lifted index and total precipitable water provided the most favorable results for locating and tracking the dryline and for understanding areas of convective inifiafion and storm growth or dissipation.