What this measures

Boner Weather Report scores real-time environmental conditions across America's 50 largest cities on a single 0–100 index reflecting their measurable impact on vascular and erectile function. The score combines five inputs: PM2.5 particle pollution, nitrogen dioxide (NO2), UV index, ambient temperature, and relative humidity.

Each input has a documented mechanism connecting it to endothelial function and nitric oxide (NO) bioavailability, the primary vascular pathway underlying erectile function. Weights reflect the strength of the published research.

Data sources

InputSourceFrequencyEndpoint
PM2.5 AQI Open-Meteo Air Quality API Hourly air-quality-api.open-meteo.com/v1/air-quality
NO2 AQI Open-Meteo Air Quality API Hourly air-quality-api.open-meteo.com/v1/air-quality
UV Index Open-Meteo Forecast API Hourly api.open-meteo.com/v1/forecast
Temperature Open-Meteo Forecast API Hourly api.open-meteo.com/v1/forecast
Humidity Open-Meteo Forecast API Hourly api.open-meteo.com/v1/forecast

Open-Meteo is an open-source weather API using ECMWF and Copernicus Atmosphere Monitoring Service (CAMS) models. PM2.5 and NO2 are returned in µg/m³ and converted to EPA AQI using standard breakpoints before scoring. Altitude is displayed per city as context but is not included in the composite score. Page data caches for 3 hours at the edge.

Scientific basis

PM2.5 and cardiovascular disease
Brook RD, et al. (2010). Particulate Matter Air Pollution and Cardiovascular Disease. Circulation, 121(21), 2331–2378.
PM2.5 exposure triggers systemic oxidative stress, endothelial dysfunction, and reduced NO bioavailability. The American Heart Association designates PM2.5 a causal risk factor for cardiovascular disease at ambient concentrations. Primary citation for city-level air quality scoring.
View source (AHA Journals) →
UVA irradiation and systemic NO release
Liu D, et al. (2014). UVA Irradiation of Human Skin Vasodilates Arterial Vasculature and Lowers Blood Pressure Independently of Nitric Oxide Synthase. Journal of Investigative Dermatology, 134(7), 1839–1846.
UVA exposure mobilizes stored NO from skin photoproducts (nitrosothiols, nitrite) into systemic circulation, reducing blood pressure via endothelium-independent vasodilation. Establishes UV index as a direct input into systemic NO availability. Note: this mechanism involves NO release from skin stores, not eNOS synthesis.
View source (JID) →
Diesel exhaust, NO2, and endothelial vasomotor function
Langrish JP, et al. (2012). Acute Exposure to Diesel Exhaust Impairs Nitric Oxide Mediated Endothelial Vasomotor Function in Humans. Hypertension, 59(3), 462–467.
NO2 exposure generates oxidative stress that impairs eNOS-mediated vasodilation, reducing the vascular endothelium's ability to produce nitric oxide. Note: this study uses controlled exposures at concentrations higher than typical ambient city levels. Brook (2010) is the primary citation for ambient-level effects. Langrish (2012) provides the NO2-specific mechanism and informs the 20% weighting.
View source (Hypertension) →

Temperature and humidity are scored on physiological plausibility: vasoconstriction at cold extremes, cardiovascular demand at heat extremes. No single primary citation covers these inputs at the city-level ambient scale. Each carries 10% weight.

Scoring formula

Each raw value is converted to a 0–100 component score via linear interpolation between breakpoints, then weighted:

Score = (PM2.5 × 0.40) + (NO2 × 0.20) + (UV × 0.20) + (Temp × 0.10) + (Humidity × 0.10)
Higher component score = better conditions for vascular function
Score range: 0 (worst) → 100 (optimal)

PM2.5 AQI component breakpoints

AQIComponent score
0100
5070
10040
15010
200+0

UV Index component breakpoints

UV IndexComponent scoreRationale
0 or null25No skin NO release (nighttime or no data)
1–2 (Low)35–60Minimal skin NO mobilization
3–5 (Moderate)60–100Increasing NO release from skin stores
6–7 (High)100Peak beneficial range (Liu 2014)
8–10 (Very High)100–70Beneficial but skin oxidative burden increases
11+ (Extreme)40–70Diminishing net benefit

Conditions scale

LabelScore rangeInterpretation
Rock Solid80–100Conditions broadly supportive of vascular function
Mostly Hard60–79Minor environmental drag, within normal range
Variable40–59Moderate friction from one or more inputs
Going Soft20–39Meaningful environmental burden on vascular function
Flat0–19High cumulative environmental drag

Limitations

Cities included

The 50 largest US cities by metropolitan population (2020 census). Coordinates reflect city center. Open-Meteo returns grid-cell values for the coordinates provided; no station radius search is required.

Disclaimer: Boner Weather Report measures outdoor environmental variables with documented vascular mechanisms. It is an environmental index, not a clinical assessment. It does not predict individual health outcomes and does not account for personal physiology, medication, health status, or indoor conditions. Nothing on this page constitutes medical advice. Data is provided for informational and entertainment purposes. Consult a qualified clinician before making health decisions based on environmental data. Weather and air quality data sourced from Open-Meteo (ECMWF/CAMS). Open-Meteo is open-source and available under the CC BY 4.0 license.