A southerly has held for 6 hours at much the same temperature as the 10°C water. No thermal steer either way, but the drift still stacks food against the northern end — the bank it is blowing into — so start there. This reads the upper water, though — a bottom bait at range feels it far less than a floater or a fish in the margins. Treat it as a tiebreaker between good swims rather than an override — features and angling pressure usually count for more.