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Active Weather Warnings

Weather in McKinney, Texas

11:57 PM
Today
Stormy Weather
Day 91°
Night 73°
Precipitation 100 %
Wind 10 mph

McKinney Weather Forecast Updated

Last updated on
Weather Forecast History
Last Year's Weather on This Day (September 30, 2025)
Rainy Night

Day

88°

Night

61°

Wind

4 mph

Precipitation

49 %

Air Quality in McKinney

NOW
21 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 0.94 µg/m³
PM10 1.52 µg/m³
O3 0.023 ppm
NO2 1.1 ppb
SO2 0.3 ppb
CO 0.11 ppm
NH3 0.23 µg/m³
NO 0 µg/m³
PM2.5 – Fine particles <2.5μm
PM10 – Inhalable particles <10μm
O3 – Ozone
NO2 – Nitrogen dioxide
SO2 – Sulfur dioxide
CO – Carbon monoxide
NH3 – Ammonia
NO – Nitric oxide

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

Show raw pollutant concentrations (µg/m³)
PM2.5 – 0.94 µg/m³
PM10 – 1.52 µg/m³
O3 – 44.84 µg/m³
NO2 – 2.09 µg/m³
SO2 – 0.81 µg/m³
CO – 121.94 µg/m³
NH3 – 0.23 µg/m³
NO – 0 µg/m³

Weather Alerts and Warnings for McKinney

Severe Future Possible

Flood Watch

Flood Watch issued September 30 at 2:26PM CDT until October 2 at 7:00AM CDT by NWS Fort Worth TX
Sep 30, 4:00 PM → Oct 2, 7:00 AM
WHAT: Flooding caused by excessive rainfall continues to be
possible.

WHERE: Portions of north central and south central Texas,
including the following counties, in north central Texas, Bell,
Bosque, Collin, Comanche, Cooke, Coryell, Dallas, Denton, Eastland,
Ellis, Erath, Falls, Fannin, Grayson, Hamilton, Hill, Hood, Hunt,
Jack, Johnson, Kaufman, Lampasas, Limestone, McLennan, Mills,
Montague, Navarro, Palo Pinto, Parker, Rockwall, Somervell,
Stephens, Tarrant, Wise and Young. In south central Texas, Milam.

WHEN: Through Friday morning.

IMPACTS: Excessive runoff may result in flooding of rivers,
creeks, streams, and other low-lying and flood-prone locations.
Low-water crossings may be flooded.

ADDITIONAL DETAILS:
- Slow moving showers and storms will likely bring widespread 2 to
3 inches of rain across the watch area. Localized areas up to 5
inches will be possible.
- weather.gov/safety/flood
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You should monitor later forecasts and be alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding develop.
Updated: Sep 30, 11:49 PM Source: NWS Alert