Trader consensus overwhelmingly favors a Seattle high of 56-57°F on March 20, driven by the National Weather Service's point forecast of 56°F under persistent cool marine air and light northerly winds suppressing instability. High-resolution models like HRRR and RAP ensembles converge on peaks in this narrow band, aligning with Seattle's March climatology—average highs near 56°F—and recent soundings showing capped boundary layers limiting convective heating. Verified observations from Sea-Tac Airport through midday confirm trajectories below 57°F. Realistic challenges include an unlikely abrupt ridge amplification or foehn-like downslope warming from the Cascades, which could nudge readings to 58°F+, but current 1000-500mb thickness maps render this improbable at under 5%.