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The southwestern United States is highly sensitive to drought, prompting efforts to understand and predict its hydroclimate. Oftentimes, the emphasis is on wintertime precipitation variability, yet the southwestern United States exhibits a summertime monsoon where a significant portion of annual precipitation falls through daily convection activities manifested by a midtropospheric ridge of high pressure. Here, we examine synoptic patterns of the southwestern ridge through a k-means clustering analysis and assess how these synoptic patterns translate into streamflow changes in the upper Colorado River basin. A linear perspective suggests ∼17% of upper Colorado River discharge at the Lee's Ferry, Arizona, gauge comes from summertime monsoon rains. The ridge of high pressure exhibits diversity in its intensity, structure, and position, inducing changes in moisture advection and precipitation. A ridge shifted north or east of its climatological center increases moisture and precipitation over the southwestern United States, while a ridge toward the south or northwest inhibits precipitation. A ridge east of its climatological center contributes to increased streamflow, whereas a ridge west or northwest of its climatological center decreases streamflow. Cooling in the central tropical Pacific and the Pacific meridional mode region favors an eastward shift of the ridge of high pressure corresponding to wet days. Eastern tropical Pacific warming favors a southward shift of the ridge corresponding to dry days. These results support an intermediate scale between climate forcing and summertime Colorado River discharge through changes in the intensity, structure, and position of the southwestern ridge of high pressure, integral to the U.S. Southwest hydroclimate. [ABSTRACT FROM AUTHOR]

The article presents a discussion on the legal issues involved in the developmental education of immigrant students in the U.S. Institutions of higher education in the U.S. are faced with the immediate question of how to serve a growing number of students from families of undocumented immigrants. It is estimated that around 65,000 students who lack immigration documentation graduate every year from the U.S. high schools. Undocumented immigrant students' prospects for completing their education is limited because often they are considered to be out-of-state or international students and thus ineligible for in-state tuition. In the last session of the Congress, a federal law was introduced that would address the barriers to higher education faced by undocumented immigrant students. The Development, Relief, and Education for Alien Minors Act was introduced by Senator Orrin Hatch and would provide a mechanism for long-term resident immigrant students to apply for legal residency and would overturn a federal law that interferes with a state's right to determine in-state tuition.