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Daily, monthly and annual mean air temperatures in Guadalajara, Mexico, were gathered from the time periods : 1926-1994, 1957-1994, 1978-1994. The heat island effect was detected in a trend analysis of the series of minimum temperatures over the period . Also, it was found that the annual mean temperature increased 0.05°C per year. A sharp increase has occurred over the last 20 years because of the abrupt expansion and industrialization of the city of Guadalajara. This study revealed the presence of a cool island in the centre of the metropolitan zone of Guadalajara (MZG) during the wet season. A cross-spectral analysis was used to study the thermal variations with different frequencies. Temperature oscillations in the MZG occurred in time intervals ranging from 3 -5 days up to 22 years. The study suggests a relationship between urban growth and temperature variations. The temperature rise relates to urban growth with a correlation co-efficient equal to 0.857.

This study evaluates the precipitation product of the Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (IMERG) over the Mexican region during the period between April 2014 and October 2015 using three different time scales for cumulative precipitation (hourly, daily and seasonal). Also, the IMERG data have been analyzed as a function of elevation given the rain gauges from the automatic meteorological stations network, located within the area of study, which are used as a reference. In the present study, continuous and categorical statistics are used to evaluate IMERG. It was found that IMERG showed better performance at the daily and seasonal time scale resolutions. While hourly precipitation estimates reached a mean correlation coefficient of 0.35, the daily and seasonal precipitation estimates achieved correlations over 0.51. In addition, the IMERG precipitation product was able to reproduce the diurnal and daily cycles of the average precipitation with a trend towards overestimating rain gauges. However, extreme precipitation events were highly underestimated, as shown by relative biases of −61% and −46% for the hourly and daily precipitation analysis, respectively. It was also found that IMERG tends to improve precipitation detection and to decrease magnitude errors over the higher terrain elevations of Mexico.

In this paper we discuss the dynamic response to mountain breeze circulation in Alchichica, a deep crater lake in Mexico. A numerical model was used to simulate integrated drift currents based on wind data sampled at 1‐h intervals. The results are compared with those measured by an ADCP. Measurements taken with a level recorder demonstrate that the mountain breeze is coordinated with diurnal level inclinations up to 11 cm and that it simulates free seiches with a period of 2.7 and 2.1 min with amplitudes equal to 7 mm and 4 mm. Measurements carried out with a SBE‐19 profiler show that in the second half of day the breeze blowing from the north causes a sinking of the thermocline by 3 meters in the southern part of the lake. It appears that periodic inclinations of the thermocline serve as the main mechanism in the generation of internal waves in Lake Alchichica.

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[1] The paper discusses the dynamic response to valley breeze circulation in Santa Maria del Oro, a volcanic lake in Mexico. Hourly records of wind measurements were used to construct a hydrodynamical model of the level fluctuations of the lake's water as well as integrated drift currents. The calculations show that the valley breeze circulation stimulates barotropic seiches in the lake with a period of 2.6 minutes and maximal level in the southwest part up to 18 mm. The drift current form two circulating rings having an opposite directions: anticyclonical in northern part of the lake and cyclonical in the southern. At the external edge of these rings the current speed can reach 20 cm/s. The measurements have shown that most part of the year the lake is strongly stratified. The maximal vertical temperature gradients are over 1°C/m in November and August, in a layer of 17 -20 m.

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