HAPPY VALLEY, OREGON WEATHER: SEPTEMBER 2021
TEMPERATURES
September 2021 averages were Normal to just above this month. It was a typical September in that the warmest weather occurred at the beginning and mostly gradually cooled as the month progressed, at least for Maximum Temperatures. The warmest period occurred from the 2nd-9th when Maxs averaged 82.5°, followed quickly by a cool down on the 10th with a daily Max. of just 64.3°, with no other reading of ≥80° until the 24th & 25th. In fact, from the 10th-23rd, the Average Max. was 70.8°, 8 of these days remaining ≤70°. However, the chilliest weather waited until month’s end with the Maxs from the 27th-30th averaging just 61.9°, and month’s coldest daily Max. of 58.4° on the 28th.
Minimum Temperatures were far less variable and were fairly consistent through the month, mostly due to clear, calm nights in the first half (allowing daytime heat at ground level to escape into the atmosphere) and many cloudy, rainy nights in the second half (the clouds acting like a blanket to retain the daytime heating).
Splitting the month in two, the Average Max./Min./Mean Temperatures were thus:
1st-15th: 77.5°/54.0°/65.7°
16th-30th: 69.7°/52.8°/61.2°
The month’s highest diurnal range was 31.5° (81.9°/50.4°) on the 2nd, the lowest only 7.2° (64.3°/57.1°) on the 10th.
PRECIPITATION
The first half of September continued the very dry weather that had been occurring since the end of February. For the 202-day period Feb. 27th – Sept. 16th, there was a total of only 6.57″. Fortunately, significant rains began falling mid-month, not ending our drought but putting a decent dent in it and greatly suppressing the area’s fire danger. The total of 3.68″ was 224% of the Normal of 1.64″ (NCEI 1991-2020 Normal for this location),. There were 9 days with measurable rain, including 2 days with >1.00″.
≥0.25″: 4
≥0.50″: 2
≥1.00″: 2
OTHER OBSERVATIONS
Sky Cover:
14 Clear, 11 Partly Cloudy, and 5 Cloudy days.
Barometric Pressure:
Average Maximum/Minimum readings were 30.10″/29.94″, with the Highest Daily Value of 30.37” on the 20th, the Lowest Daily Reading of 29.66” on the 17th.
Relative Humidity:
Maximum/Minimum Averages were 92%/53%, having a Daily Maximum of 98% on the 18th-20th, 28th, 29th; Daily Minimum of 25% on the 4th.
Dew Point:
Averages were a Maximum/Minimum of 59°/48°, with a Daily Maximum of 65° on the 5th & 9th, Daily Minimum of 33° on the 16th & 17th.
Wind:
Daily Average Speed was 1.0 MPH and the highest Daily Average Wind Speed was 2.5 MPH on the 21st; The Daily Average Gust was 12.2 MPH and the Highest Gust reached 27 MPH from the SSW on the 17th.
HAPPY VALLEY MONTHLY WEATHER FORM: SEPTEMBER 2021 (click the month/year to link to the form)
Cover Photo: Pink Sunset, 9/6/2021.
2 thoughts on “HAPPY VALLEY, OREGON WEATHER: SEPTEMBER 2021”
Love your picture.
Thank you Cathie! I could see a glow when I was in my home office then looked outside. So I went out and took the pic. It was rather mesmerizing.
Jeff