Advisory Circular 91-92 notes that pilots who are skilled in preflight weather assessments and overall risk mitigation are better prepared to make in-flight decisions. It describes Flight Service, optimally, as "a consultative resource that can be utilized when needed."

Short version: You can call us if you fly into a thunderstorm with minimum fuel, but if that happens, you probably don't understand the role of Flight Service in the National Airspace System.

The AIM (5-1-1) continues this theme: "Pilots who prefer to contact Flight Service are encouraged to conduct a self-brief prior to calling. Conducting a self-brief before contacting Flight Service provides familiarity of meteorological and aeronautical conditions applicable to the route of flight and promotes a better understanding of weather information."

AC 91-92 details the three types of preflight briefings available to pilots:

• Standard Briefing: This includes conditions and Significant Meteorological Information (SIGMET) that may influence the pilot in planning, altering, or cancelling a proposed route or flight.
• Abbreviated Briefing: This supplements mass disseminated data or updates a previous briefing, or is limited to specific information.
• Outlook Briefing: This should be obtained when the proposed departure is six (6) hours or more from the time of the briefing. This type of briefing is provided for planning purposes only.

The Standard Briefing Checklist should be part of a self-briefing before contacting Flight Service:

• Type of flight planned (IFR/VFR).
• Aircraft identification.
• Aircraft type.
• Departure point.
• Route of flight.
• Destination (alternate airports if needed).
• Flight altitude(s).
• Estimated time of departure (ETD) and estimated time en route (ETE).

Pilots also should gather weather and aeronautical information before contacting Flight Service:

• Weather systems and/or air masses synopsis
• Current Conditions
• Adverse Conditions
• En Route Forecast.
• En Route Forecast.
• Destination Forecast
• Winds Aloft
• NOTAMs
• Special Use Airspace (SUA)
• ATC Delays

Awareness of adverse conditions includes:

• Low-level wind shear.
• Thunderstorms.
• Reported icing.
• Frontal zones along the route of flight.
• SIGMETs.
• Airmen's Meteorological Information (AIRMET).
• Convective SIGMETs.
• Center Weather Advisories (CWA).
• Aviation Watch Notification Messages

AC 91-92 also offers Do's and Dont's:

Do:

• Establish personal minimums that reflect your level of proficiency.
• Plan ahead and obtain an outlook briefing.
• Obtain a standard briefing as close to your departure time as possible.
• Obtain an abbreviated briefing just before takeoff if your standard briefing is 1 hour or more old or if the weather is questionable.
• Allow more margin for weather at night. Clouds and the horizon may be difficult or impossible to see on dark nights. Always stay above the highest terrain until a safe landing is assured.
• Check PIREPs, NOTAMs, AIRMETs, and SIGMETs.
• Consider VFR flight following (ATC workload permitting).
• Consider filing a VFR flight plan.
• Have a contingency plan for alternates if unexpected circumstances arise.
• Be familiar with any applicable disclaimers related to the accuracy of the information provided by the subscribed commercial service.

Don't:

• Plan flights that exceed your personal minimums or level of proficiency.
• Plan flights in or near current or forecast convective activity.
• Fly in or near thunderstorms. Scattered thunderstorms may be safely circumnavigated, but do not try to fly through or under one or closer than 20 nm) from one.
• Continue VFR into IMC. Instead, wait it out or turn around if you find en route weather lowering below your personal limits.
• Forget that areas en route, or even near airports, may be below VFR minimums, even though reporting stations are at or near VFR minimums. Be especially cautious when the temperature and dewpoint spread is 3° C or less: fog may form.
• Proceed "on top," hoping to find a hole in the clouds at the other end or hoping to get ATC to talk you down if you get caught on top.
• Fly into areas of rain when the air temperature is near freezing. Ice can form on the windshield, impairing forward vision, and on the wings, which can decrease aircraft performance, as well as other aircraft control, lifting, and nonlifting surfaces (e.g., propellers, tail surfaces, or intakes).
• Hesitate to declare an emergency with ATC whenever the safety of flight is at risk.
• Plan on using cockpit weather displays as a tactical means of navigating through convective weather.

Remember: Flight into known icing conditions is prohibited for all aircraft not properly certificated for flight in icing conditions or not properly equipped with ice protection equipment.