We derive the W boson mass from the Lattice Field Medium (LFM) framework, obtaining m_W = 80,429 MeV—a zero-parameter prediction that agrees with the controversial CDF 2022 measurement but disagrees sharply with the Standard Model. The Prediction: LFM: 80,429 MeV (derived, not fitted) CDF 2022: 80,433.5 ± 9.4 MeV → 0.5σ agreement Standard Model: 80,357 ± 6 MeV → 12σ disagreement Hypothesis Framework: General Hypothesis: The true W boson mass is approximately 80,429 MeV, not the Standard Model prediction of 80,357 MeV. Null Hypothesis (H₀): The Standard Model is correct. The true W mass is 80,357 ± 6 MeV. The CDF 2022 measurement is a systematic error. Alternative Hypothesis (H₁): The true W mass is approximately 80,430 MeV. The CDF 2022 measurement is correct and the Standard Model prediction is wrong. LFM Prediction: m_W/m_e = χ₀²(24χ₀ - 20) = 157,396 gives m_W = 80,429 MeV, which supports H₁. Rejection Criteria: If LHC consensus settles on m_W = 80,360 ± 10 MeV → H₀ not rejected, LFM prediction falsified If LHC consensus settles on m_W = 80,430 ± 10 MeV → H₀ rejected, LFM prediction confirmed Physical Foundation: The LFM framework parameter χ₀ = 19 is derived from first principles—it equals the minimum degrees of freedom required to evolve the LFM substrate at each lattice point: Component DOF Explanation 8D Laplacian stencil 17 Center + 2×8 neighbors in phase space Time history (leapfrog) +1 Need Ψ(t-1) to compute Ψ(t+1) Second coupled field +1 χ field couples to Ψ field TOTAL 19 = χ₀ This structural derivation is validated by the CMB: χ₀ = 19 predicts n_s = 0.9667 (Planck measured 0.9649 ± 0.0042). The same parameter yields spacetime dimensions D = (χ₀-11)/2 = 4 and particle generations N_gen = (χ₀-1)/6 = 3—consistency conditions violated by other integer values. Falsifiability: This prediction takes an unambiguous side in an active experimental controversy. Additional precision measurements from CMS and refined ATLAS analyses are anticipated. However, given the complexity of systematic uncertainties in hadron collider W mass measurements, definitive resolution of the current CDF/ATLAS tension may take several years.