Environmental Geology Mr. Paul Lowrey Stacey Singleton, Cassandra Combs, Dwight Stephenson, Matt Smithyman Hurricanes EMPACTS Project, Spring 2017 Northwest Arkansas Community College, Bentonville, AR 72712
What is a hurricane? A hurricane is like a tornado but on the ocean. Wind speeds must be at least 74 mph to become a hurricane or Category 1 status Less than 74 mph is considered a storm
Where do hurricanes come from? They normally form between 5 to 15 degrees latitude (north and south) Usually formed of West coast of Africa (along equatorial lines)
Differences between Hurricanes and Typhoons The only difference between the two is geography! In the Atlantic ocean & eastern Pacific, they are called Hurricanes! In the western Pacific ocean they are called typhoons
Tropical Storm - a cyclone with sustained winds that range from 39 mph to 73 mph Stages of a Hurricane (Definitions) Tropical Wave - a low pressure trough moving westward with trade winds(storm) Tropical Disturbance - an organized area of thunderstorms that usually forms in the tropics Tropical Cyclone - organized low pressure that forms over tropical or subtropical waters Tropical Depression - organized area of low pressure with sustained winds of 38 mph or less
Formation of Hurricanes Hurricanes form over warm ocean waters (80 F or up!) The air must cool pretty quick the higher you go Called hurricanes in Western Hemisphere /Typhoons in Eastern
Path of Hurricanes
Hurricane Categories This is the Saffir-Simpson Hurricane Scale Category Winds (MPH) Pressure (millibars) Pressure (inches) Storm Surge (feet) Damage 1 74-95 <980 <28.94 4-5 Minimal 2 96-110 979-965 28.91-28.50 6-8 Moderate 3 111-130 964-945 28.47-27.91 9-12 Extensive 4 131-155 944-920 27.88-27.17 13-18 Extreme 5 >155 <920 <27.17 >18 Catastrophi c
Watch & Warn! Tropical Storm Watch - Tropical storm conditions with sustained winds from 39-74 mph are possible in your area within the next 36 hours Tropical Storm Warning - Tropical storm conditions are expected in your area within the next 24 hours Hurricane Watch - Hurricane conditions with sustained winds of 74 mph or greater are possible in your area within the next 36 hours. This watch should trigger your family s disaster plan, and protective plans should be initiated. Hurricane Warning - Hurricane conditions are expected in your area within 24 hours. Once this warning has been issued, your family should be in the process of completing protective actions and deciding the safest location to be during the storm Coastal Flood Watch - The possibility exists for the inundation of land areas along the coast within the next 12 to 36 hours Coastal Flood Warning - Land areas along the coast are expected to become, or have become,
Predication Hurricane season starts June 1 and ends November 30 La Nina years are more active States on the east coast with higher precipitation Meteorologists can track the path and predict landfall
How to Stay Safe (Before Hurricane) Have a disaster plan ready Board up windows and bring in outdoor furniture that could blow away Make sure to know all of the evacuation routes Keep a first aid kit, canned food, bottled water, battery operated radio, flashlight, protective clothing, and instructions to turn off utilities
How to Stay Safe (During Hurricane) Stay away from flood zones Always stay indoors during a hurricane Leave mobile homes and go to a shelter If your home isn t on high ground, go to a shelter If officials tell you to evacuate, evacuate!
Stay away from standing water, it could be electrically charged from downed power lines. How to Stay Safe (After Hurricane) Stay inside until it is safe to come out. Check for injured or trapped people. NEVER put yourself in danger. Keep an eye out for flooding. Do not attempt to drive in flood waters.
How hurricanes affect non coastal residents Even if you do not live near the beach, hurricanes can still affect the weather where you live with heavy rainfall and strong winds.