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Anadyr Strait, located at the northernmost reaches of the Bering Sea, influences pan‐Arctic climate through processes occurring in the strait as the Siberian Coastal Current carries water from the subpolar North Pacific Ocean into the western Arctic Ocean. A sharp sea surface temperature front near the Anadyr Strait segregates a tongue‐shaped mass of warm water from areas of cold‐water upwelling proximate to the Siberian coast. To clarify dynamical processes in this region, we conducted shipboard observations through and near the Anadyr and Bering straits during the summers of 2017 and 2018. Microstructure measurements show enhanced turbulence near the sea floor as strong throughflow occurs in the narrow straits. Direct observations of ocean currents indicate that the semidiurnal barotropic tide partly contributes to the near‐bottom currents driving mixing. Frictional effects accompanying the barotropic current are examined using a three‐dimensional regional model. Bottom friction produces a westward Ekman current in the bottom boundary layer, which then causes upwelling of underlying cold water on the western (Siberian) side of the Anadyr Strait. Secondary circulation across the strait is also maintained by the near‐surface eastward velocity, which is established by the steep slope of the main thermocline. Plain Language Summary: Water from the North Pacific passing through the narrow straits of the Bering Sea can affect climate change in the western Arctic Ocean. Anadyr Strait is an important pathway in the northern Bering Sea, but the oceanographic processes occurring there are poorly understood because of a paucity of in situ observations. We obtained new data from the region in the summers of 2017 and 2018, which allows us to study the mechanisms generating the near‐surface cold water in Anadyr Strait that has been identified from satellites. Our study reveals that the cold water is lifted up to the surface from the bottom layer when a strong current passes through the strait. According to our direct measurements and numerical simulations, friction between the current and the sea floor generates cold‐water upwelling and the horizontal temperature front. This improved understanding of ocean processes in the northern Bering Sea will help improve our understanding of how the North Pacific and Arctic oceans will interact as climate varies. Key Points: The sea surface temperature front near Anadyr Strait was investigated during two shipboard surveys in the summers of 2017 and 2018Coastal upwelling of cold water occurs as part of cross‐strait cell circulation, where bottom friction is the controlling factorStratified throughflow with semidiurnal tidal oscillation facilitates the development of the frictional bottom boundary layer [ABSTRACT FROM AUTHOR]