Cyclonic Circulations of Tropical Origin
Table 10-1 lists tropical warnings and associated
wind speeds where applicable:
Issuance of Advisories and Warnings
Tropical Cyclone Formation Alert (TCFA)
advisories are issued whenever conditions are right for
the development of a tropical cyclone.
Tropical depression/storm and hurricane/typhoon
warnings are issued via AUTODIN and the Fleet
Multichannel Broadcast every 6 hours for storms in the
Northern Hemisphere.
They originate from three
places:
1. NAVLANTMETOCCEN Norfolk issues
warnings for storms in the North Atlantic, Caribbean
Sea, and Gulf of Mexico.
2. NAVPACMETOCCEN Pearl Harbor issues
warnings for storms in the eastern and mid-Pacific.
3. NAVPACMETOCCEN WEST Guam issues
warnings for storms in the western Pacific and the
Indian Ocean.
HIGH SEAS WARNINGS
These warnings are issued every 12 hours whenever
actual or forecast significant wave heights in an ocean
area of the Northern Hemisphere equal or exceed 12
feet.
THUNDERSTORM WARNINGS
These warnings are issued as warranted. If there is
information received from the National Severe Storms
Center with regard to threat of tornadic activity, the
information is reviewed, and if warranted, disseminated
as a Severe Thunderstorm Watch/Warning.
ADDITIONAL WARNINGS/ADVISORIES
We will now briefly discuss two additional
warnings/advisories that, if conditions warrant, would
be included in forecasts/travel advisories.
Freezing Rain
If the synoptic situation is conducive to freezing
rain, the information would be reflected in all
forecasts/travel advisories until the likelihood ceases.
Table 10-1.-Tropical Warning and Associated Wind Speeds
Extreme Temperatures
When conditions warrant, Heat Index and
Wind-Chill are reflected in all forecasts/travel
advisories until the likelihood ceases.
VERIFICATION OF WARNINGS,
ADVISORIES, AND
FORECASTS
LEARNING OBJECTIVES:
Verify all
warnings, advisories, and forecasts for
accuracy to determine whether or not
conditions occurred as forecasted.
To provide the optimum product it is very important
that all forecasts and warnings be verified after the fact.
All NAVMETOC and USMC commands have
procedures in place to verify the accuracy of all
products, whether they be Small Croft, Gale/Storm, or
High Seas Warnings.
By monitoring observations from underway units
and closely monitoring weather features, enroute
weather forecasts can be fine tuned.
The following are products that are routinely
verified for accuracy:
High Seas Warnings
Gale/Storm Warnings
Small Craft Warnings
Optimum Track Ship Routing (OTSR) Requests
Enroute weather forecasts
10-2
