I live in the San Francisco Bay Area and have always had a fascination with weather, its extremes, and stats. I'm also in CoCoRaHS: Belmont 0.7 WSW.
By: BelmontJeff, 2:56 AM GMT on October 17, 2013
SEPTEMBER was a beautiful month, with 22 Clear days, 0 Cloudy days, and only 6 days with A.M. Fog (1 of these with Visibility ≤1/4 Mile).
TEMPERATURE: September is now the warmest month of this Calendar Year for both the Max. and Min. Temps. The Avg. Max. Temp. of 79.2° was 3.9° above June, now the 2nd warmest; the Avg. Min. Temp. of 57.5° was 1.4° warmer than August, the previous warmest.
The Avg. Max. Temp. was quite variable throughout the month, peaking on the 7th at 94.2° (and a total of 5 days ≥90°). With a general decline through the month, Min. Temps. differed only 10.8° from warmest to coldest readings.
The greatest diurnal Temperature range was 36.3° on the 6th (6 total days with a range ≥30.0°); the least was 8.0° on the 21st (mid-day rain).
PRECIPITATION: A surprise soaking rain occurred on the 21st, mostly 1030-1435 Hrs. (Totals: Vantage Pro2 gauge = 0.67"; Lake Region gauge = 0.74"). This was the greatest Calendar-Day rain since Dec. 2012 (VP2 = 1.96" (23rd); LR = 2.11" (24th)). The September Normal Ppt is 0.15". The current Calendar-Year Total Rainfall continues well below normal: VP2 = 3.03", LR = 3.49" (Normal for January-September period is 17.30").
WIND: 29 of the 30 days recorded peak gusts of ≥10 MPH, with 16 of these being ≥15 MPH, and only 1 of ≥20 MPH.
Updated: 3:03 AM GMT on October 17, 2013