- Climate normals
- 30-year averages of monthly temperature and precipitation. NOAA publishes new normals every decade; this site uses the 1991-2020 normals.
- Average high (tmax)
- The average daily maximum temperature for a given month, measured in degrees Fahrenheit.
- Average low (tmin)
- The average daily minimum temperature for a given month, measured in degrees Fahrenheit.
- Average temperature (tavg)
- The mean of the daily high and low temperatures for a month — roughly what "typical" weather feels like.
- Precipitation
- Total rainfall plus the water equivalent of snow, reported in inches.
- Last spring frost
- The average calendar date of the final overnight low at or below 32°F in spring. Gardeners use this to time the planting of tender annuals and warm-season vegetables.
- First fall frost
- The average date of the first overnight low at or below 32°F in autumn — the traditional end of the growing season.
- Growing season
- The number of days between the average last spring frost and average first fall frost.
- p10 / p50 / p90
- Probability thresholds. For frost dates: p10 is the 10th percentile (early), p50 the median (average), p90 the 90th percentile (late). There's a 10% chance of frost after the p10 spring date, 50% after p50, and 90% after p90.
- GHCN / GHCN-Daily
- Global Historical Climatology Network — NOAA's primary source of daily temperature and precipitation observations worldwide.
- Station
- An official weather observation site, usually at an airport or dedicated meteorological facility, that feeds data into the GHCN.