METEOROLOGY FLIGHT PLANNING
OPNAVINST 3710.7 Restrictions
The OPNAVINST 3710.7 Series restrictions for USN/USMC aircraft regarding WWs is listed as
Except for operational necessity, emergencies, flights involving all-weather research projects or
weather reconnaissance, pilots shall not file into or through areas the National Weather Service
(NWS) has issued a WW unless one of the following exceptions applies:
Storm development has not progressed as forecast for the planned route. In such situations:
a. VFR filing is permitted if existing and forecast weather for the route permits such
b. IFR flight may be permitted if aircraft radar is installed and operative, thus permitting
detection and avoidance of isolated thunderstorms.
c. IFR flight is permissible in positive control areas if visual meteorological conditions
(VMC) can be maintained, thus enabling aircraft to detect and avoid isolated thunderstorms.
2. Performance characteristics of the aircraft permit an en route flight altitude above existing or
developing severe storms.
1. It is not the intent to restrict flights within the areas
encompassed by or adjacent to a WW area unless storms have
actually developed as forecast.
2. Only a qualified forecaster can make the determination as to
whether storm development has progressed as forecast.
CNATRA WW (CAWW)
The Chief of Naval Air Training (CNATRA) may also issue warnings in the form of a CNATRA
Aviation Weather Warning (CAWW) for the local operating areas in the absence of WWs and/or
SIGMETs and when conditions warrant such action. These warnings will be issued when one or
more of the following criteria have been reported, detected by radar, or are imminently expected
within 100 miles of the station and WW coverage is inadequate or nonexistent:
SEVERE WEATHER WATCHES, MILITARY ADVISORIES, AND PIREPS