The 2004 North American Monsoon Experiment (NAME) provided an unprecedented observing network for studying the structure and evolution of the North American monsoon. This paper focuses on multiscale characteristics of the flow during NAME from the large scale to the mesoscale using atmospheric sounding data from the enhanced observing network.The onset of the 2004 summer monsoon over the NAME region accompanied the typical northward shift of the upper-level anticyclone or monsoon high over northern Mexico into the southwestern United States, but in 2004 this shift occurred slightly later than normal and the monsoon high did not extend as far north as usual. Consequently, precipitation over the southwestern United States was slightly below normal, although increased troughiness over the Great Plains contributed to increased rainfall over eastern New Mexico and western Texas. The first major pulse of moisture into the Southwest occurred around 13 July in association with a strong Gulf of California surge. This surge was linked to the westward passages of Tropical Storm Blas to the south and an upper-level inverted trough over northern Texas. The development of Blas appeared to be favored as an easterly wave moved into the eastern Pacific during the active phase of a Madden-Julian oscillation.On the regional scale, sounding data reveal a prominent sea breeze along the east shore of the Gulf of California, with a deep return flow as a consequence of the elevated Sierra Madre Occidental (SMO) immediately to the east. Subsidence produced a dry layer over the gulf, whereas a deep moist layer existed over the west slopes of the SMO. A prominent nocturnal low-level jet was present on most days over the northern gulf. The diurnal cycle of heating and moistening (Q 1 and Q 2 ) over the SMO was characterized by deep convective profiles in the mid-to upper troposphere at 1800 LT, followed by stratiform-like profiles at midnight, consistent with the observed diurnal evolution of precipitation over this coastal mountainous region. The analyses in the core NAME domain are based on a gridded dataset derived from atmospheric soundings only and, therefore, should prove useful in validating reanalyses and regional models.

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Two studies are presented, which examine cue reactivity in dieting. Methods: Experiment 1 investigated whether the presence of a preferred food affected dieters' performance on measures of attention, reaction time, and motor speed. The manipulation did not affect the performance. Experiment 2 investigated the performance of dieters (N = 19), highly restrained non-dieters (N = 18) and low-to-medium restrained eaters (N = 34) on two simple reaction time tasks. Subjects were either required to imagine their favorite food or to imagine their favorite holiday while completing a reaction time task. Results: In the food condition, both dieters and restrained nondieters displayed significantly slower reaction times during the first three of five blocks of the task than the low-to-medium restrained eaters. Conclusions:The results are discussed in terms of Tiffany's (Psychological Review 97:147-168, 1990) model of cue reactivity in that different abstinent states produce comparable effects upon performance.

Gulf surges are disturbances that move northward along the Gulf of California (GOC), frequently advecting cool, moist air from the GOC or eastern tropical Pacific Ocean into the deserts of the southwest United States and northwest Mexico during the North American Monsoon (NAM). Little attention has been given to the dynamics of these disturbances because of the lack of reliable high-resolution data across the NAM region. High temporal and spatial observations collected during the 2004 North American Monsoon Experiment are used to investigate the structure and dynamical mechanisms of a significant gulf surge on 13-14 July 2004. Integrated Sounding Systems deployed along the east coast of the GOC and an enhanced network of rawinsonde sites across the NAM region are used in this study. Observations show that the 13-14 July gulf surge occurred in two primary stages. The first stage was preceded by anomalous low-level warming along the northern GOC on 13 July. Sharp cooling, moistening, and increased low-level south-southeasterly flow followed over a 12-18-h period. Over the northern gulf, the wind reached ϳ20 m s Ϫ1 at 750 m AGL. Then there was a brief respite followed by the second stage-a similar, but deeper acceleration of the southerly flow associated with the passage of Tropical Storm (TS) Blas on 14 July. The initial surge disturbance traversed the GOC at a speed of ϳ17-25 m s Ϫ1 and resulted in a deepening of the mixed layer along the northern gulf. Dramatic surface pressure rises also accompanied the surge. The weight of the evidence suggests that the first stage of the overall surge itself consisted of two parts. The initial part resembled borelike disturbances initiated by convective downdrafts impinging on the low-level stable layer over the region. The secondary part was characteristic of a Kelvin wave-type disturbance, as evident in the deeper layer of sharp cooling and strong wind that ensued. Another possible explanation for the first part is that the leading edge of this Kelvin wave steepened nonlinearly into a borelike disturbance. The second stage of the surge was associated with the increased circulation around TS Blas.

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