Welcome to Yokota Air Base, Japan. If this is your first typhoon season in Japan, there is nothing to be scared of! With a little education and preparation you too can have a safe and uneventful typhoon season. Your friendly Yokota AB Combat Weather Team has assembled a small list of Frequently Asked Questions (FAQ) and helpful tips to get you off on the right foot, or left if you are in uniform, for the upcoming season.
See our Typhoon Awareness pamphlet here, current as of May 2023.
FAQs:
What is the difference between a Typhoon and a Hurricane?
What is a Tropical Cyclone?
Why do we see typhoons at Yokota AB?
When is the typhoon season and how often do we see typhoons at Yokota AB?
What does TCCOR stand for and what do the different levels represent?
Where can I find out current TCCOR conditions and storm information?
What can I do to get ready for typhoon season?
What actions do I take when a TCCOR is declared?
Q: What is the difference between a Typhoon and a Hurricane? (top)
A: There is no physical difference between the two, both are mature tropical cyclones. The terms typhoon and hurricane merely refer to the geographic region of the world in which the storm forms. A storm is called a hurricane when it forms in the Western Hemisphere (North Atlantic Ocean, Caribbean Sea, Gulf of Mexico, and in the eastern and central North Pacific east of the date line). In various other locations like the Northwest Pacific these storms are referred to as typhoons or strictly as a tropical cyclone.
Q: What is a Tropical Cyclone? (top)
A: Tropical cyclone is general term used to describe a weather system that forms in the tropics, has organized thunderstorms, and has a counter-clockwise rotation (in the northern hemisphere, clockwise in the southern hemisphere). As a tropical cyclone increases/decreases in intensity it is identified as one of the following based on defined thresholds:
Tropical Depression
A tropical cyclone that has a defined surface circulation with wind speeds 29-38 MPH (25-33 knots) and organized thunderstorms.
Tropical Storm
A tropical cyclone that has a defined surface circulation with wind speeds 39-73 MPH (34-63 knots) and an organized system of strong thunderstorms.
Typhoon
A tropical cyclone that has a defined surface circulation with wind speeds 74-148 MPH (64-129 knots) and an organized system of intense thunderstorms.
Super Typhoon
A tropical cyclone that has a defined surface circulation with wind speeds > 150 MPH (130 knots) and an organized system of intense thunderstorms.
Q: Why do we see typhoons at Yokota AB? (top)
A: The Kanto Plain, which is located in southeastern Honshu, is on the northern edge of the most active typhoon producing region in the world (26.7 storms annually). The Western Pacific has a huge area of extremely warm water that extends well north of the equator, which provides a great breeding ground for these powerful storms. In addition to the favorable formation area, the warm Kuroshio ocean current that runs along the eastern coast of Japan allows tropical cyclones to maintaining a majority of their energy while moving northward.
Q: When is the typhoon season and how often do we see typhoons at Yokota AB? (top)
A: The official typhoon season for the Northwest Pacific lasts from 1 June to 30 November, with the peak for Yokota between August and September. The average number of typhoons that pass within 125 nautical miles of Yokota AB annually is two. These storms can produce heavy rain (upwards of 10 inches) and strong winds. Once every 2 to 3 years, tropical cyclones produce winds greater than 50 knots. The strongest wind experienced at Yokota AB was 105 MPH (91 knots) from Typhoon Ida in 1966.
Q: What does TCCOR stand for and what do the different levels represent? (top)
A: TCCOR stands for Tropical Cyclone Conditions Of Readiness. The different levels of tropical cyclone readiness are based upon the timing of destructive tropical cyclone winds of 57 MPH (50 knots) or greater. The levels are defined as:
TCCOR 4: Destructive winds possible within 72 hours
TCCOR 3: Destructive winds possible within 48 hours
TCCOR 2: Destructive winds anticipated within 24 hours
TCCOR 1: Destructive winds anticipated within 12 hours
TCCOR 1 CAUTION: Sustained 39-56 MPH winds (34-49 knots) are occurring
TCCOR 1 EMERGENCY: Sustained destructive winds (57 MPH or 50 knots) are occurring
TCCOR STORM WATCH: Due to the close proximity of a tropical cyclone and/or erratic movements, the typhoon still poses a threat to affect installation
RECOVERY: Period of time to determine damage/create safe zones
ALL CLEAR: Storm is over and not forecast to return
Q: Where can I find out current TCCOR conditions and storm information? (top)
A: Television and the radio stations will be the best source of weather information. TCCOR conditions will be broadcast at frequent intervals when a tropical cyclone poses a threat to the Kanto Plain. For radio information tune into EAGLE 810 AM, and for information via the television set your dial to Channel 19, the 374th Operations Support Squadron weather flight channel. For current storm tracks, visit the Joint Typhoon Warning Center at: https://www.metoc.navy.mil/jtwc/jtwc.html
Q: What can I do to get ready for typhoon season? (top)
A: Here are a few things you can do prior to Typhoon Season:
- Stock up on essential emergency items NOW!
- Purchase batteries
- Purchase bottled water in jugs and bottles
- Purchase candles with lighter/matches
- Flashlights
- Battery operated radio/TV
- 1 week supply of non-perishable foods
- Review evacuation plan
- Locate natural disaster shelters
- Know typhoon information sources
- Know TCCORs and actions to take
Q: What actions do I take when a TCCOR is declared? (top)
A: Specific TCCOR Measures
TCCOR 4
- Obtain emergency supplies
- Flashlights
- Batteries
- Bottled water
- Portable radio
TCCOR 3
- Fill vehicle gas tank
- Fill gas grill tank
- Fill water containers
- Ensure you have sufficient money
TCCOR 2
- Secure outside items
TCCOR 1
- Move high valued items to the center of your quarters away from windows
- Tape windows if winds are expected to be greater than 100 knots (115 MPH)
TCCOR 1 CAUTION
- All non-essential travel is suspended
- All non-essential personnel remain indoors
- Monitor weather information sources for changes in TCCOR conditions
TCCOR 1 EMERGENCY
- All personnel indoors stay away from windows
- Monitor weather information sources for changes in TCCOR conditions
TCCOR RECOVERY & STORM WATCH
- Remain indoors while damage cleanup is accomplished
- Monitor weather sources (radio/TV) for ALL CLEAR notice!
TCCOR ALL CLEAR
- Individuals are permitted outdoors