A primary motivation for this study comes from the need to improve the ability of polymer matrix composites to withstand lightning strikes. In particular, we are concerned with lightning strike damage in composite wind turbine blades. The problem is essentially multiphysic, as the electric-current-induced temperature in the composite blade subjected to a lightning strike may reach up to 1,200 °C, leading to extensive thermal damage including surface damage, delamination, cracks, matrix decomposition, fiber breakage and sublimation, and abrupt failure of the blade. In this work, the thermal response of the polymer-matrix composite laminate used in a Sandia 100-meter All-glass Baseline Wind Turbine Blade (SNL 100-00) subjected to lightning strike is studied. The tip region composite panel is considered, as it has been reported in the literature that the blade tip is more susceptible to lightning strike than the remaining parts of the blade. A physical model to show the surface interaction between the lightning arc and the composite structure has been developed. The model provides time- and electric-current-dependent variation of the lightning arc radius and lightning-current-induced heat flux generated at the composite surface. The temperature-dependent thermal properties of the VectorPly E-LT 5500 unidirectional 2 E-glass fiber vinyl ester resin matrix fabric and SNL triaxial [±45]22 E-glass fiber vinyl ester resin matrix fabric used in the wind blade tip composite panel were derived using available experimental data. The formulated nonlinear transient heat transfer problem with moving boundary is solved using the finite element method. The solution procedure accounts for phase transitions in the materials, and the obtained results include temperature field profiles and evolution of the thermal damage.