WX Score Explained
How the WX Score is calculated, what factors affect it, and how to interpret your number.
What Is the WX Score?
The WX Score is a 0–100% rating of how well the forecast weather conditions match your specific aircraft capabilities and personal minimums. It starts at 100% (perfect conditions) and points are deducted for each weather factor that approaches or exceeds your limits.
Important: The WX Score is an advisory tool — not a flight authorization. Two pilots with different experience levels and aircraft will get different scores for the same flight because their personal minimums differ. The PIC always makes the final go/no-go decision.
GO
Conditions are within your minimums. Normal flight planning applies.
MARGINAL
Some conditions are close to or slightly exceed your limits. Extra caution needed.
NO-GO
Conditions significantly exceed your minimums. Consider postponing or rerouting.
How Points Are Deducted
The score starts at 100% and deductions are applied for each weather factor that doesn't meet your minimums. The size of each deduction depends on how far conditions exceed your limits.
Ceiling & Visibility Deductions
Points deducted when forecast ceilings or visibility fall below your personal minimums at departure or arrival.
- • Soft limit exceeded: 5–15 points (marginal conditions)
- • Hard limit exceeded: 100 points (automatic NO-GO)
Crosswind Deductions
Based on the crosswind component on the best-aligned runway at departure and arrival. The deduction scales with your pilot certificate and total hours:
- • Student/Sport/Recreational: Stricter crosswind limits
- • Private (<500 hrs): Standard crosswind limits
- • Private (≥500 hrs) / Commercial / ATP: Higher crosswind tolerance
Wind Gust Deductions
Separate deductions for wind gusts that exceed your maximum crosswind gust limit. Heavy gusts at departure or arrival can significantly reduce the score.
Turbulence & Icing Deductions
Based on multi-model analysis (HRRR, GFS, ECMWF) of turbulence severity at your cruise altitude and icing conditions relative to the freezing level. Moderate or severe conditions detected by numerical models will reduce the score even if the AI text assessment is favorable.
Convective & Thunderstorm Scoring
Thunderstorm and convective activity penalties use a horizon-scaled approach. A thunderstorm forecast 36 hours out does not carry the same weight as one 3 hours out, because convective forecasts become much more accurate as departure approaches.
Horizon Scaling
The penalty for convective activity is multiplied by a factor that increases as departure approaches:
36+ hours
~40%
of full penalty
12–24 hours
~60%
of full penalty
6–12 hours
~80%
of full penalty
0–6 hours
100%
full penalty
Threat Level Refinement
The base convective penalty is further refined by the threat level from model data and WPC (Weather Prediction Center) analysis:
- • Isolated: Lower multiplier — small penalty for scattered pop-up cells
- • Scattered: Medium multiplier — moderate penalty for organized convection
- • Widespread: Full multiplier — significant penalty for large-area activity
Why horizon scaling matters: Before this system, a PROB40 thunderstorm forecast in a TAF could cause a 40-point score swing every few hours as WPC updates rolled in. With horizon scaling, distant forecasts have a proportionally smaller impact, so your score is more stable and reflects the actual risk at the time of departure.
Pre-Flight Check (Within 12 Hours)
For flights departing within 12 hours, PlaneWX runs a detailed server-side pre-flight check that evaluates every weather parameter against your personal minimums and aircraft capabilities. If any hard limit is exceeded, the score is automatically set to 0%.
What the Pre-Flight Check Evaluates
- •Ceiling and visibility at departure and arrival vs. your soft/hard minimums
- •Crosswind and gust components on the best available runway
- •PROB30/PROB40 TAF periods for thunderstorms, freezing rain, and low visibility
- •TEMPO periods with significant weather (TS, FZRA, SN)
- •Active SIGMETs and Convective SIGMETs along the route
For flights more than 12 hours out: The score is calculated using AI-generated weather analysis and model data, without the detailed pre-flight check. As your flight approaches, the briefing will automatically refresh and the pre-flight check will activate, potentially changing the score.
Score Breakdown
Tap the WX Score ring or the “Score Breakdown” button to see exactly which factors contributed to your score. Each deduction shows:
- • Category: Which weather factor (ceiling, wind, turbulence, etc.)
- • Points: How many points were deducted
- • Reason: A plain-English explanation of why
- • Location: Whether it applies to departure, arrival, or en-route
Tip: If you disagree with a deduction, check your Personal Minimums and Aircraft Profile settings. The score is based entirely on your configured limits — adjusting them will change your score.