Hurricanes in NC Eric Angat Teacher

How do the hurricanes that affect North Carolina form? Essential Question How do the hurricanes that affect North Carolina form?

Six Necessary Conditions for Hurricane Development Warm ocean waters of at least 78°F (26°C) At least 5° latitude from the equator Low vertical wind shear Moisture in the mid-troposphere Unstable Conditions Pre-existing disturbance http://climate.ncsu.edu/climate/hurricanes/development.php

Warm Ocean Waters Tropical cyclones thrive off the heat content of the warm tropical and subtropical oceans. Warm ocean water evaporates from the surface and is taken in by the developing cyclone. As the water vapor rises, it eventually condenses into liquid water, forming clouds and releasing energy in the form of heat. Tropical cyclones use the released energy to gain organization and strength. Thus the warmer the water, the more energy can be extracted during condensation, and the stronger the storm can grow. However, tropical cyclones require a large temperature difference between the ocean surface and upper-level air to be most efficient at turning the heat energy into mechanical energy (in the form of strong winds). http://climate.ncsu.edu/climate/hurricanes/development.php

2. At least 5º latitude from the equator Tropical cyclones are well known for their rotation, which is easily visible from a satellite loop of the storm. However, in order to acquire this spin they must obtain it from the rotation of the earth. At the equator the influence of earth's spin is zero and it increases moving toward the poles (this is known as Coriolis force). While there is nothing magical about 5º degrees latitude, there is just enough influence from the earth's spin to be favorable for tropical cyclone development. http://climate.ncsu.edu/climate/hurricanes/development.php

3. Low Vertical Wind Shear Vertical wind shear is the difference in wind speed and direction at two different heights in the atmosphere. An example of shear would be to have wind increasing rapidly with height. Tropical cyclones have trouble developing in high shear environments because it displaces the thunderstorms in the cyclone away from its center of circulation. The thunderstorms are the primary location for the cyclone to gain energy through condensation (thinking back to the first criteria). By moving the thunderstorms away from the center of circulation, the rotation weakens because it is not receiving a steady supply of energy. http://climate.ncsu.edu/climate/hurricanes/development.php

4. Moisture in the mid-troposphere Tropical cyclones require a moist mid-troposphere to help keep their clouds and thunderstorms in tact. Dry air introduced into the mid-levels will begin eating away at the cyclone's clouds. Furthermore, the dry air can become wrapped into the circulation of the cyclone, disrupting the thunderstorms and causing asymmetries in the structure of the cyclone.

5. Unstable Conditions Tropical cyclones contain thunderstorms, which ingest moist air near the surface. The most effective way to bring the air near the surface up into the thunderstorms is if that air is unstable. Unstable air is typically very warm, moist air (such as over the tropical oceans) that when lifted will continue to rise on its own. The more unstable the air is, the more rapidly it will rise. Rapidly rising air helps to create vigorous thunderstorms which contribute to the overall tropical cyclone. http://climate.ncsu.edu/climate/hurricanes/development.php

6. Pre-existing disturbance A pre-existing disturbance can be considered a seedling that, if placed under the previous five conditions, may grown to be a tropical cyclone. While a disturbance can come in many different forms, the most typical in the Atlantic Basin are African Easterly Waves. These waves are generally a complex of thunderstorms that moves off the west coast of Africa. Provided the previous 5 conditions are in place over the Atlantic Ocean off the west coast of Africa, a disturbance moving over that area may develop. http://climate.ncsu.edu/climate/hurricanes/development.php

TROPICAL STORM possible on Memorial Day weekend on SC, NC coast. http://wspa.com/2016/05/23/tropical-storm-possible-on-memorial-day-weekend-on-sc-nc-coast/ http://tropicalatlantic.com/models/models.cgi?large=1

Isobars Less than 500 add 10 and move the decimal point to the right once. 1004 mb 1017.6 mb Less than 500 add 10 and move the decimal point to the right once. http://www.tropicaltidbits.com/storminfo/sfcplots/sfcplot_91L_latest.png 1016.5 mb

https://wxmankyle. files. wordpress https://wxmankyle.files.wordpress.com/2015/09/tropical-spaghetti-models.png

What are spaghetti models? What are spaghetti models? Spaghetti models (also called spaghetti plots) is the nickname given to the multiple computer models when shown together because the individual model tracks can somewhat resemble strands of spaghetti. Why would I want to view spaghetti models? In short, it can give you additional insight into where a tropical storm or hurricane may head. First, for a developing storm system that has not officially become a tropical depression or a tropical storm, spaghetti models can serve to give you an early heads up as to where a future tropical storm or hurricane may head. However, once a storm is official, the National Hurricane Center releases an official best guess path based on their analysis of the different model data and other factors. At this point, the NHC forecasts are what should be used for planning. The spaghetti models can still be useful though. For instance, in the case of Tropical Storm Debby, the original NHC storm path had her going straight west to Texas. If you viewed the spaghetti models at that time, you would have had a glimpse into just how uncertain Debby's path was because the spaghetti models had her making landfall from anywhere from Texas to Florida to everywhere in between. The Different Spaghetti Models XTRP TVCN NHC BAMD BAMM BAMS GFDL UKM NGPS AVNO AEMN HWRF CM APxx CLP5

What are spaghetti models What are spaghetti models? Spaghetti models (also called spaghetti plots) is the nickname given to the multiple computer models when shown together because the individual model tracks can somewhat resemble strands of spaghetti. Why would I want to view spaghetti models? In short, it can give you additional insight into where a tropical storm or hurricane may head. First, for a developing storm system that has not officially become a tropical depression or a tropical storm, spaghetti models can serve to give you an early heads up as to where a future tropical storm or hurricane may head. http://www.cyclocane.com/spaghetti-models/

Coriolis effect is cause by Earth rotation. Coriolis Forcean artifact of the earth's rotationOnce air has been set in motion by the pressure gradient force, it undergoes an apparent deflection from its path, as seen by an observer on the earth. This apparent deflection is called the "Coriolis force" and is a result of the earth's rotation. As air moves from high to low pressure in the northern hemisphere, it is deflected to the right by the Coriolis force. In the southern hemisphere, air moving from high to low pressure is deflected to the left by the Coriolis force. The amount of deflection the air makes is directly related to both the speed at which the air is moving and its latitude. Therefore, slowly blowing winds will be deflected only a small amount, while stronger winds will be deflected more. Likewise, winds blowing closer to the poles will be deflected more than winds at the same speed closer to the equator. The Coriolis force is zero right at the equator. This process is further demonstrated by the movie below. QuickTime (2.0M)  MPEG (0.9M)Real Life Example:  This movie of a ball rolling across the surface of a rotating merry-go-round is a helpful demonstration of the Cori http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/fw/crls.rxml

The Different Spaghetti Models XTRP TVCN NHC BAMD BAMM BAMS GFDL UKM NGPS AVNO AEMN HWRF CM APxx CLP5 http://www.cyclocane.com/spaghetti-models/