ForeFlight Weather Imagery

Private Pilot License (PPL) Notes

This section provides an overview of using the ForeFlight app's Imagery section for comprehensive preflight weather planning and understanding various weather forecast charts and graphics.

Accessing ForeFlight Weather Imagery:

1. Open the ForeFlight app and navigate to the Imagery section.
2. Choose the geographic area:
   1. By default, images are for the United States from the Aviation Weather Center.
   2. Tap the Global button at the bottom for worldwide weather data.
3. View specific images:
   1. The left side lists collections of weather products grouped by type.
   2. Tap a collection to view thumbnails, then tap a thumbnail to view full size.
   3. Pinch to zoom in on images if needed.
4. Navigate between images:
   1. Swipe left or right to view next or previous images.
   2. Tap Close to return to the main menu.
5. Manage favorites and recents:
   1. Tap the star icon to mark an image as a favorite.
   2. Access favorites by tapping the two-star icon on the main Imagery page.
   3. View recently viewed charts by tapping the Recents button.

Understanding Weather Products:

1. Use a top-to-bottom approach:
   1. Start with big picture weather maps and long-range forecasts at the top.
   2. Work down toward current observations affecting smaller areas.
2. Big Picture Analysis:
   1. Begin with major weather systems:
      1. Identify highs, lows, cold fronts, and warm fronts.
      2. Determine the movement of these systems.
   2. Use Prog Charts to get an overview of major weather trends.
   3. Assess how large systems may influence your flight route and planning.
3. Precipitation Products:
   1. Review the 6-Hour Quantity of Precipitation and 12-Hour Probability of Precipitation (PoP) charts:
      1. Helps identify areas with potential moisture or precipitation.
      2. Correlate precipitation with possible adverse weather conditions like icing or IFR.
   2. Use these forecasts for long-term planning, as they extend up to 7 days ahead.
4. Convective Hazards:
   1. Examine convective hazard charts to identify areas of potential thunderstorms.
   2. Determine if precipitation areas indicate rain or more severe weather.
   3. Extended forecasts go beyond 24 hours for effective long-range planning.

Graphical Aviation Forecasts:

1. Cloud Forecasts:
   1. Depicts cloud coverage across the U.S. including AIRMETs for icing and mountain obscuration.
   2. Legend identifies color codes for Few, Scattered, Broken, and Overcast skies.
   3. Displays forecasts of cloud bases and tops in MSL altitudes.
2. Surface Forecasts:
   1. Includes visibility, surface winds, precipitation, and other weather hazards.
   2. Legend provides color codes for visibility ranges from less than 1 SM to over 5 SM.
   3. Wind barbs indicate surface wind strength and direction.
   4. Standard weather symbols depict rain, snow, fog, and thunderstorms.
   5. Available for the entire U.S. or individual regions with forecasts from 3 to 18 hours ahead.

Forecasts at Altitude:

1. Winds Aloft Forecasts:
   1. Helps choose optimal cruise altitude for fastest flight.
   2. Provides insights into movement of highs and lows.
   3. Divided into:
      1. Low-level (below 12,000 feet).
      2. Mid-level (15,000 to 24,000 feet).
      3. High-level (30,000 to 48,000 feet).
   4. Available every 3,000 feet with forecasts up to 48 hours ahead.
2. Icing Forecasts:
   1. Essential for instrument pilots to assess in-flight icing risks.
   2. Provides detailed forecasts by altitude and time.
   3. Understand the difference between:
      1. Icing Probability: Likelihood of encountering icing conditions.
      2. Icing Severity: Expected intensity of icing (light, moderate, severe).
   4. Compare different altitudes to find levels above or below potential icing.
3. Turbulence Forecasts:
   1. Helps find smoother ride altitudes.
   2. Divided into low-level, mid-level, and high-level sections.
   3. Further categorized by cause:
      1. Clear Air Turbulence.
      2. Mountain Wave Turbulence.
   4. Select All to view combined turbulence risks.
   5. Forecasts available up to 18 hours ahead.
4. Use these forecasts to plan route and altitude for safer and more comfortable flights.

Observations vs. Forecasts:

1. Model-Driven Forecasts:
   1. Based on computer models predicting future conditions.
   2. Useful for flights planned a few days in advance.
2. Real-Time Observations:
   1. Include satellite imagery, radar, and Pilot Reports (PIREPs).
   2. Essential for flights approaching departure time.
   3. Provide current, region-specific weather information.
3. Combining Forecasts and Observations:
   1. Use forecasts for long-term planning and understanding trends.
   2. Rely on observations for up-to-date weather conditions.
   3. Overlay observations on the Maps page for comprehensive situational awareness.

Remember, utilizing ForeFlight's Imagery section effectively enhances preflight planning by providing a thorough understanding of weather conditions, ensuring safer and more informed flying decisions.