United States storm systems
In the United States, storm systems powerful enough to cause blizzards usually form when the jet stream dips far to the south, allowing cold, dry polar air from the north to clash with warm, humid air moving up from the south.When cold, moist air from the Pacific Ocean moves eastward to the Rocky Mountains and the Great Plains, and warmer, moist air moves north from the Gulf of Mexico, all that is needed is a movement of cold polar air moving south to form potential blizzard conditions that may extend from the Texas Panhandle to the Great Lakes and Midwest. A blizzard also may be formed when a cold front and warm front mix together and a blizzard forms at the border line. Another storm system occurs when a cold core low over the Hudson Bay area in Canada is displaced southward over southeastern Canada, the Great Lakes, and New England. When the rapidly moving cold front collides with warmer air coming north from the Gulf of Mexico, strong surface winds, significant cold air advection, and extensive wintry precipitation occur. Low pressure systems moving out of the Rocky Mountains onto the Great Plains, a broad expanse of flat land, much of it covered in prairie, steppe and grassland, can cause thunderstorms and rain to the south and heavy snows and strong winds to the north. With few trees or other obstructions to reduce wind and blowing, this part of the country is particularly vulnerable to blizzards with very low temperatures and whiteout conditions.
Next, the area around the heel is cleansed and numbed, and a small scalpel is used to cut the Achilles tendon. The incision is small so there is minimal bleeding and no need for stitches. The skin is covered with a small dressing, and the foot is placed into a final long leg cast in a fully corrected position. This cast is typically left in place for three weeks. During this time, the Achilles tendon will regrow in a lengthened position. Bracing: After successful correction is achieved through serial casting and Achilles tenotomy, the foot must be kept in a brace to prevent it from returning to the deformed position over the first few years of a childs life. The brace is made up of two shoes or boots that are connected to each other by a bar that is bent under the shoes at 10-15 degrees, or curved to create 10-15 degrees dorsiflexion. This device is also called a foot abduction brace (FAB) or more generally boots and bar (BnB). At first, the brace is worn full-time (23 hours per day) on both feet, regardless of whether the clubfoot affects one or two feet. After 3 months of 23/7 wear, the brace is worn less frequently by gradually reducing hours a couple at a time, every couple months so that hours are down to 12-14 per day at or around a year old.