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Advisory Analysis Guide

Understanding how weather advisories are validated against real pilot reports.

Overview

The Advisory Analysis tool helps you understand how accurate turbulence forecasts really are. It compares official weather advisories (G-AIRMETs, SIGMETs, and CWAs) against actual pilot reports (PIREPs) to show you which forecasts were verified by real-world conditions.

This is useful for anxious flyers who want to better understand the relationship between forecasted turbulence and what pilots actually experience. Over time, you can see patterns in which types of advisories tend to be most accurate.

How It Works

1

Collect Advisories

The system gathers all active and recently expired turbulence advisories from G-AIRMETs, SIGMETs, and CWAs. Each advisory has a defined geographic area, altitude range, and valid time period.

2

Match PIREPs

For each advisory, the system searches for pilot reports of turbulence that fall within the advisory area, altitude range, and time window. PIREPs that match are considered validation evidence.

3

Calculate Score

Each matching PIREP contributes to the validation score based on turbulence severity. Moderate turbulence adds 1 point, severe adds 2 points, and extreme adds 3 points. The total is normalized to a 0-100 scale.

4

Classify Result

Based on the score, each advisory is classified as Verified, Partially Verified, or Unverified. This gives you a quick way to see how well the forecast matched reality.

Advisory Sources

The tool analyzes three types of aviation weather advisories:

G-AIRMET

Graphical Airmen's Meteorological Information. These are forecasts for moderate turbulence covering broad areas. Issued by the Aviation Weather Center, they provide 6-hour forecasts updated every 3 hours.

Typical coverage:Large geographic areas, often covering multiple states
Reliability note:Good for predicting general areas of turbulence, though the exact boundaries and intensity can vary.

SIGMET

Significant Meteorological Information. Domestic SIGMETs are issued for severe or extreme turbulence, volcanic ash, or severe icing. These are the most serious turbulence warnings.

Typical coverage:Specific regions within the US airspace, usually tied to significant weather events
Reliability note:High priority warnings. When a SIGMET is issued for turbulence, pilots take it very seriously.

CWA

Center Weather Advisory. These are short-term advisories (up to 2 hours) issued by Air Route Traffic Control Centers. They fill the gap between routine forecasts and SIGMETs.

Typical coverage:Specific areas within a center's airspace, often smaller than G-AIRMETs
Reliability note:Very current and specific. CWAs often indicate developing conditions before formal advisories are issued.

Understanding Validation Scores

Each advisory receives a validation score from 0 to 100 based on how many pilot reports confirmed the forecasted turbulence:

Verified

(Score: 50 - 100)

Multiple pilot reports confirm turbulence in the advisory area. The forecasted conditions were accurate.

What this means: The advisory was a reliable warning. Pilots encountered the predicted turbulence.

Partially Verified

(Score: 1 - 49)

Some pilot reports confirm turbulence, but fewer than expected for the area and time period covered.

What this means: The advisory may have been overly broad, or conditions were less severe than forecast.

0

Unverified

(Score: 0)

No pilot reports of turbulence were found within the advisory area during its valid time.

What this means: Either the turbulence did not occur, was avoided by pilots, or there was insufficient traffic to report it.

Scoring Breakdown

  • Moderate turbulence PIREPs: +1 point each
  • Severe turbulence PIREPs: +2 points each
  • Extreme turbulence PIREPs: +3 points each
  • Verified threshold: 5+ raw points (normalized to 50+)
  • Partial threshold: 1-4 raw points (normalized to 1-49)

Filters and Sorting

The header bar provides controls to customize your view:

Source Filters

Toggle which advisory types you want to see. You can view G-AIRMETs, SIGMETs, and CWAs individually or in combination.

Tip: Comparing different sources helps you understand which forecast types are most reliable for your typical routes.

Include Expired

Show advisories that have already ended. This is essential for validation analysis since you need to wait until an advisory expires to fully evaluate its accuracy.

Tip: Set the time range (6, 12, or 24 hours) to control how far back you want to analyze.

Sort Options

Order the advisory list by validation score, time, or number of matching PIREPs. High score first shows the best-verified advisories.

Tip: Sort by "Fewest PIREPs" to find advisories in areas with low traffic that may lack validation data.

Stats Summary Bar

At the top of the page, you will see a summary bar showing:

  • Total advisories: How many advisories match your current filters
  • Active vs Expired: Current advisories versus those that have ended
  • Verified count: How many advisories have been confirmed by PIREPs
  • Average score: The mean validation score across all shown advisories

Advisory Details

Click on any advisory card to see detailed information:

Validation Statistics

The detail panel shows the normalized score (0-100), raw validation score, and total number of matching PIREPs. You can see exactly how the score was calculated.

PIREP Severity Breakdown

See how many moderate, severe, and extreme turbulence reports matched the advisory. This helps you understand the intensity of turbulence pilots actually encountered.

Time Correlation Chart

A chart showing when PIREPs were filed during the advisory period. This reveals whether turbulence was constant or concentrated at certain times.

Matching PIREPs List

A scrollable list of all PIREPs that matched the advisory, showing aircraft type, altitude, turbulence intensity, and report time. Each PIREP shows how many points it contributed to the score.

Interpreting Results

  • High verification rate is good news: It means forecasters are accurately predicting where turbulence will occur, so you can trust the advisories.
  • Unverified does not mean safe: An unverified advisory might mean conditions were avoided by pilots, there was low traffic, or the turbulence was less widespread than forecast.
  • Compare advisory types: Over time, you may notice certain types (like CWAs or SIGMETs) have higher verification rates than others.
  • Consider the time of day: More PIREPs are filed during busy travel times, so advisories during peak hours may have better validation data.

Remember that this tool is for educational purposes - it helps you understand how weather forecasting works and how reliable the predictions are. Pilots use these same advisories when planning flights, and the validation data shows they are generally doing a good job of predicting turbulence.