What do the guards of the tomb of the unknown soldier do during bad weather?

The Sentinels at the tomb of the Unknowns (Tomb of the Unknown Soldier) walk the line in all weather. A prime example of this is of Hurricane Isabel. On September 23rd 2003 Hurricane Isabel struck the Washington DC Area, a contingency plan had been established stating that if winds are above 120 miles per hour you do not have to stand guard and walk the line. During the Hurricane as cars and other objects were lifted from the ground in the District area, and projectiles flew through the air the Sentinels continued to walk the line rather than take shelter in the surround building.