The Adige Valley is one of the major corridors connecting the Po Plain with the inner Alps. A series of permanent weather stations and one wind profiler provide regular monitoring of air temperature, atmospheric pressure, global solar radiation, wind speed and direction over the 140 km valley length and in the adjacent plain. Data from these stations are analyzed for a subset of days on which weather conditions favoured full development of diurnal valley winds in the period 2012–2014. The analysis highlights typical features in the alternating patterns of diurnal up‐valley winds and nocturnal down‐valley winds. In particular, the wind intensity depends linearly on the along‐valley pressure gradient, supporting the concept of a quasi‐steady balance between the pressure gradient and surface friction. Also, in agreement with previous investigations, the amplitude of the surface pressure cycle increases in the up‐valley direction, causing the reversal of the horizontal pressure gradient twice per day. In contrast, no appreciable along‐valley variation in the diurnal temperature range is found. The analysis of surface temperature and pressure measurements suggests that the larger pressure perturbations found far into the valley are caused by the increased depth of the atmospheric layer subject to heating and cooling. Local inhomogeneities in the valley cross‐section, in particular in the vicinity of a large basin, cause temperature and pressure perturbations that are strong enough to alter the typical cycle of down‐ and up‐valley winds. Similarly, local wind convergence over the major cities during the night is explained in terms of the urban heat island effect.

Assessing the accuracy of gridded climate data sets is highly relevant to climate change impact studies, since evaluation, bias correction, and statistical downscaling of climate models commonly use these products as reference. Among all impact studies those addressing hydrological fluxes are the most affected by errors and biases plaguing these data. This paper introduces a framework, coined Hydrological Coherence Test (HyCoT), for assessing the hydrological coherence of gridded data sets with hydrological observations. HyCoT provides a framework for excluding meteorological forcing data sets not complying with observations, as function of the particular goal at hand. The proposed methodology allows falsifying the hypothesis that a given data set is coherent with hydrological observations on the basis of the performance of hydrological modeling measured by a metric selected by the modeler. HyCoT is demonstrated in the Adige catchment (southeastern Alps, Italy) for streamflow analysis, using a distributed hydrological model. The comparison covers the period 1989–2008 and includes five gridded daily meteorological data sets: E‐OBS, MSWEP, MESAN, APGD, and ADIGE. The analysis highlights that APGD and ADIGE, the data sets with highest effective resolution, display similar spatiotemporal precipitation patterns and produce the largest hydrological efficiency indices. Lower performances are observed for E‐OBS, MESAN, and MSWEP, especially in small catchments. HyCoT reveals deficiencies in the representation of spatiotemporal patterns of gridded climate data sets, which cannot be corrected by simply rescaling the meteorological forcing fields, as often done in bias correction of climate model outputs. We recommend this framework to assess the hydrological coherence of gridded data sets to be used in large‐scale hydroclimatic studies.

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The Ora del Garda is a coupled lake and valley breeze regularly blowing from the 2 northern shorelines of Lake Garda, in the Italian Alps, especially during warm-season 3 clear-sky days. The climatological characteristics of this wind are investigated through http://mc.manuscriptcentral.com/joc