Support Neighborhoods Offset Winter Damage Act of 2025 or the SNOW Act of 2025This bill authorizes Federal Emergency Management Agency (FEMA) grant funding for winter storm hazard mitigation and requires FEMA rulemaking to expand assistance for winter storms. It also increases the federal cost share for various FEMA grants, for any hazard type, in rural or disadvantaged areas.The bill specifically authorizes the use of grant funding under the Hazard Mitigation Grant Program (HMGP) and Building Resilient Infrastructure and Communities program to reduce the risk of future damage in areas affected by winter storms, such as by acquiring snow removal equipment. Also, under current FEMA policy, in determining eligibility and recommending a presidential major disaster declaration for a snowstorm, FEMA’s considerations include whether data shows record (or near record) snowfall and whether estimated statewide costs meet applicable thresholds. The bill requires FEMA to create regulations waiving these eligibility requirements for a major disaster declaration for a snowstorm in certain circumstances. FEMA must also create regulations to provide certain assistance for winter storms, including for debris removal and specified infrastructure, as well as individual and emergency assistance when the state determines the storm exceeds state and local capacity. In addition, for any hazard type, the bill requires FEMA to increase the federal cost share from 75% to 90% for certain assistance provided in rural or disadvantaged areas. It also authorizes an increased HMGP federal cost share amount from 75% to 90% for assistance in rural or disadvantaged areas.