> ## Documentation Index
> Fetch the complete documentation index at: https://offthepace.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# stg_weather

> Weather snapshot nearest each lap start.

<Note>Part of the [Staging](/transform/families/staging) family.</Note>

Weather snapshot nearest each lap start. Bronze weather samples (≈1 Hz) are matched to laps with ASOF semantics: for each lap, the sample with the largest session\_time\_s that is still ≤ lap\_start\_time\_s (conditions as the lap begins), falling back to the first sample for laps starting before the first reading. One row per driver × lap; covers all races 2018–2024 with zero source nulls.

## Lineage

```mermaid theme={null}
flowchart LR
  stg_laps --> stg_weather
  stg_weather --> int_compound_cliff_predicted
  stg_weather --> int_pit_strategy_cost_curve
  stg_weather --> int_track_evolution
  style stg_weather fill:#e40404,stroke:#e40404,color:#fff
```

## Overview

| Property          | Value                                  |
| ----------------- | -------------------------------------- |
| Layer             | `staging`                              |
| Family            | [Staging](/transform/families/staging) |
| Contract enforced | No                                     |
| Upstream          | [`stg_laps`](./stg_laps)               |

**1 tests** [guard](/transform/ci/overview) this model  -  0 generic, 1 singular.

## Columns

| Column                   | Type      | Nullable | Tests | Description                                                                                                                                                                                                                                                                                |
| ------------------------ | --------- | -------- | ----- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `lap_id`                 | `varchar` | Yes      |       | Foreign key to stg\_laps.                                                                                                                                                                                                                                                                  |
| `race_year`              | `integer` | Yes      |       | Season year.                                                                                                                                                                                                                                                                               |
| `race_id`                | `varchar` | Yes      |       | Numeric FastF1 event id cast to string.                                                                                                                                                                                                                                                    |
| `driver_id`              | `varchar` | Yes      |       | FastF1 three-letter driver code.                                                                                                                                                                                                                                                           |
| `lap_number`             | `integer` | Yes      |       | Lap index within the race.                                                                                                                                                                                                                                                                 |
| `weather_session_time_s` | `double`  | Yes      |       | Session clock (s) of the matched weather sample.                                                                                                                                                                                                                                           |
| `ambient_temp_c`         | `double`  | Yes      |       | Air temperature (°C).                                                                                                                                                                                                                                                                      |
| `track_temp_c`           | `double`  | Yes      |       | Track-surface temperature (°C).                                                                                                                                                                                                                                                            |
| `rainfall_flag`          | `boolean` | Yes      |       | TRUE when rainfall was detected at the sample.                                                                                                                                                                                                                                             |
| `humidity_pct`           | `double`  | Yes      |       | Relative humidity (%).                                                                                                                                                                                                                                                                     |
| `wind_speed_ms`          | `double`  | Yes      |       | Wind speed (m/s).                                                                                                                                                                                                                                                                          |
| `wind_direction`         | `integer` | Yes      |       | Wind direction (degrees, 0–359).                                                                                                                                                                                                                                                           |
| `pressure_hpa`           | `double`  | Yes      |       | Station air pressure (hPa). 100% non-null in bronze across 2018–2024; range 778–1024 hPa (the low end is Mexico City's altitude, not a defect). Staged for contract completeness — air density derived from it was measured as a degradation feature and rejected as inside harness noise. |