Baltimore no means uncommon for the rain-snow line to set up in the metro area. Freezing rain and sleet occurs a few times each winter in the area, as warm air overrides cold air at the low to mid-levels of the atmosphere. When the wind blows from the east, the cold air gets dammed against the mountains to the west and the result is freezing rain or sleet. Spring and autumn are warm, with spring being the wettest season in terms of the number of precipitation days. Summers are hot and humid with a daily average in July of , and
Hail . GR is derived from the French word grêle. Smaller-sized hail, as well as snow pellets, use the coding of GS, which is short for the French word grésil. Terminal velocity of hail, or the speed at which hail is falling when it strikes the ground, varies. It is estimated that a hailstone of in diameter falls at a rate of , while stones the size of in diameter fall at a rate of . Hailstone velocity is dependent on the size of the stone, friction with air it is falling through, the motion of wind it is falling through,