At Angel Aviation, we believe that weather knowledge isn’t just a checkride item — it’s the key to safe IFR flight. Before your DPE has you brief an approach or divert for a pop-up thunderstorm, they’ll test whether you can analyze, interpret, and apply real-time and forecasted weather data to make informed decisions.

This guide covers everything in ACS Area IV: Weather Information, referencing FAA resources, decoding charts and reports, and showing you exactly what your examiner wants to hear in the oral.

🎯 What the Examiner Is Looking For

Under Instrument Rating ACS Area IV, your DPE wants to see that you can:

  • Obtain and interpret aviation weather data from approved sources

  • Apply weather reports and forecasts to your preflight planning

  • Understand the impact of adverse weather conditions on IFR operations

  • Make safe, informed go/no-go and diversion decisions

Let’s break it down into key knowledge areas and practical tips.

🌐 Weather Sources You Must Know

📚 Ref: FAA-H-8083-15B (IFH), FAA Advisory Circular 00-45, Aviation Weather Center (AWC)

Be able to identify where you’re getting your data — and whether it’s legal for IFR flight.

✅ Primary Sources:

  • Flight Service (FSS/1800WXBRIEF or Leidos)

  • Aviation Weather Center (aviationweather.gov)

  • ForeFlight/other FAA-approved EFBs

  • ATIS, ASOS, AWOS

✅ Supplemental Sources (not for sole reliance):

  • TV/Internet weather apps

  • Social media or non-FAA-approved websites

💡 Angel Tip: Always cite an FAA-approved source when briefing the examiner — it shows professionalism and legality.

🧩 METARs, TAFs, and Beyond: What You Must Decode

📚 Ref: AC 00-45H, AIM Chapter 7

Your examiner may hand you raw reports or ask for an interpretation. Make sure you can confidently brief:

✅ METARs – Hourly surface observations
 ✅ TAFs – Terminal forecasts (including tempo/prob groups)
 ✅ AIRMETs – Widespread moderate hazards (icing, turbulence, IFR)
 ✅ SIGMETs – Severe or extreme weather (TS, turbulence, volcanic ash)
 ✅ Convective SIGMETs – Thunderstorms and severe convection
 ✅ PIREPs – Pilot-reported conditions aloft
 ✅ Winds and Temps Aloft – Wind direction, velocity, and forecasted temps
 ✅ Radar and Satellite Imagery – Areas of precipitation or cloud cover
 ✅ Surface Analysis/Prog Charts – Big-picture movement of systems

🧠 Be ready to brief this weather for each phase of flight: departure, en route, and arrival.

✈️ How to Brief a Weather Scenario

Your DPE might ask:

“Walk me through the current weather for your planned flight from KPHX to KDEN.”

Here’s how to impress them:

  1. Overview: “I’m departing under VFR conditions, with developing IFR along the route near the front shown on the Prog Chart.”

  2. METAR/TAF: “KPHX shows clear skies, light winds; KDEN has deteriorating visibilities and ceilings with a TEMPO group forecast for snow.”

  3. Advisories: “AIRMET Sierra for widespread IFR, Convective SIGMET along eastern New Mexico.”

  4. PIREPs: “Multiple moderate turbulence reports at FL180 over northern Arizona.”

  5. Decision-making: “I’d delay the flight or file alternate routing to avoid embedded convective activity.”

⚖️ Legal Weather Minimums to Know

📚 Ref: 14 CFR §91.169, §91.103, §91.155

Know these cold:

  • IFR Filing Weather: Must obtain weather reports/forecasts for departure, destination, and alternate

  • Alternate Required? If destination weather is below 2000 ft ceiling and 3 SM visibility within 1 hour of arrival, list an alternate

  • Alternate Minimums:

    • Precision approach: 600 ft ceiling / 2 SM vis

    • Non-precision: 800 ft / 2 SM

    • No instrument approach: VFR descent from MEA

🧠 Questions You Might Hear

✅ “How do you know if an alternate is required?”
 ✅ “Interpret this METAR and tell me if you can depart.”
 ✅ “Where would you find the freezing level?”
 ✅ “What is an AIRMET Zulu, and how would it affect your flight?”
 ✅ “What’s your personal minimum for crosswinds, icing, or thunderstorm avoidance?”

🧭 Bonus: Go-To FAA References

  • AC 00-45H – Aviation Weather Services

  • AIM Chapter 7 – Aviation Weather

  • §91.169 – IFR flight plan requirements

  • §91.103 – Preflight action

  • §91.155 – Weather minimums

  • FAA Weather Products website – aviationweather.gov

🧾 Final Thoughts from Angel Aviation

Weather isn’t just something you check before flight — it’s a living, evolving part of your IFR decision-making process. By mastering weather data interpretation and applying it to real-world flying, you’ll prove to your examiner that you’re ready to operate safely in the system.