'Boreas' was a U-boat wolfpack operation in the Arctic Ocean, in the area between the north of German-occupied Norway and the Svalbard islands group, against the QP.15 convoy (19 November/9 December 1942).

The wolfpack comprised U-209, U-212, U-376, U-378, U-405, U-456, U-586, U-592, U-601 and U-625, and for the loss of none of its own number sank two ships (9,825 tons).

On 17 November the QP.15 convoy departed Arkhangyel’sk with 31 unladen ships, two of which had to turn back. The eastern local escort force comprised the anti-aircraft ship Ulster Queen, the minesweepers Britomart, Halcyon, Hazard and Sharpshooter, and the Soviet flotilla leader Baku and destroyer Sokrushitelny. The ocean escort comprised the corvettes Bergamot, Bluebell, Bryony and Camellia, and the minesweeper Salamander. The convoy and its escort were joined in the Barents Sea on 20 November by the British destroyers Echo (until 22 November), Faulknor, Intrepid, Icarus and Impulsive (until 26 November) and then Middleton (22/30 November), Musketeer, Orwell and Oakley (23/30 November). Patrolling farther to the west were the heavy cruisers London and Suffolk, and the destroyers Forester, Obdurate and Onslaught. The British submarines Trespasser and Seadog, Free French Junon, Free Norwegian Uredd and Soviet L-20 were positioned off the entrances to fjords in the north of German-occupied Norway to intercept any any attempt by German surface warships to break out.

On 20 November the convoy was scattered by a severe storm. Parts of Baku's superstructure were blown off and, additionally beset by severe leaks in her bows and boiler rooms, the warship managed to reach harbour only with difficulty. Sokrushitelny fared worse and broke in two. The destroyers Razumny, Kuybyshev and Uritsky were sent to help and managed to rescue 187 men in very heavy seas, and Sokrushitelny sank on 22 November.

German air reconnaissance was unable to locate the convoy in the bad weather, but nonetheless on 23 November Kapitänleutnant Hans Benkers’s U-625 and Kapitänleutnant Peter-Ottmar Grau’s U-601 each managed to sink one ship, the 5,851-ton British Goolistan and 3,974-ton Soviet Kuznets Lesov respectively.