SmogRank / United States / California / Manteca

Manteca, month by month

Manteca has a measured daily mean on 1,277 days since 1 January 2023. Its worst month was December 2024, at 69 US AQI (19.0 µg/m³), 300th of 2,616 cities on that month's world ranking. Its cleanest was March 2024, at 19 US AQI (3.5 µg/m³). 2025 averaged 42 US AQI (7.5 µg/m³), against 46 US AQI (8.3 µg/m³) in 2024.

Every month since 2023

Each square is a month's mean PM2.5 in US AQI from Manteca's measured days, with its place on that month's world ranking under it. A month has a mean once 70% of its days are measured, the rule the monthly rankings use; under that, the square gives the days measured. Each square opens that month's ranking with Manteca marked; each year, the year's. A dashed square is the running month, so far.
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

Months without a mean, and why

2 months
MonthWhy
Mar 20239 of 31 days measured; a month needs 22. The others: 20 missing from OpenAQ's archive, 2 with under 18 hours of readings or readings that failed our checks.
Feb 20231 of 28 days measured; a month needs 20. The others: 25 missing from OpenAQ's archive, 2 with under 18 hours of readings or readings that failed our checks.

A day counts once 18 hours of it are measured; a month needs 70% of its days.

Manteca's worst months

MonthUS AQIDays measuredWorld rankEpisode
December 2024 6919.0 µg/m³31 of 31300thof 2,616California, United States, December 2024
California and Oregon, United States, December 2024
December 2023 6315.6 µg/m³30 of 31265thof 2,247Western United States and Mexico, December 2023
California and Oregon, United States, December 2023
January 2025 6215.2 µg/m³31 of 31477thof 2,474California, United States, January 2025
January 2026 6114.4 µg/m³31 of 31786thof 2,617California and Oregon, United States, January 2026
December 2025 5712.4 µg/m³30 of 31925thof 3,006California, United States, December 2025
November 2023 5611.9 µg/m³30 of 30304thof 2,243–

Monthly means over the days measured; finished months only. World rank: its place on that month's world ranking of every city with enough days. Each month opens that ranking.

Manteca's worst days

DayUS AQIEpisode
7 Dec 2024 12244.0 µg/m³California and Oregon, United States, December 2024
17 Dec 2023 10738.1 µg/m³California and Oregon, United States, December 2023
20 Sept 2023 10737.9 µg/m³California and Oregon, United States, September 2023
16 Dec 2023 10236.0 µg/m³California and Oregon, United States, December 2023
6 Dec 2024 10035.4 µg/m³California and Oregon, United States, December 2024
5 Dec 2024 9834.5 µg/m³California and Oregon, United States, December 2024
11 Dec 2024 9733.6 µg/m³California and Oregon, United States, December 2024
22 Sept 2023 9633.4 µg/m³California and Oregon, United States, September 2023
30 Aug 2023 9532.7 µg/m³North-western United States and Canada, August 2023
15 Dec 2023 9331.6 µg/m³California and Oregon, United States, December 2023

Daily means, the highest since 1 Jan 2023; the WHO's daily guideline is 15 µg/m³. Each date opens that day's world ranking, and each episode the bad-air spell it was part of.

Use this history

SmogRank, PM2.5 monthly and daily means, Manteca, United States, 1 Jan 2023 – 11 Oct 2026. Monitor data from AirNow, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/us/manteca/history (accessed 12 Oct 2026).

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You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.

Manteca now: the last 24 hours, its ranks today and the last 12 months day by day.

Updated 2026-10-12 18:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some low-cost readings: Sensor.Community, ODbL (data and licence). Some readings: Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver), no reuse terms published (why we use them).