September 2018 was unremarkable overall regarding rainfall and temperature. The dry spell at the end of August continued for another 7 days and there was little substantial rain thereafter until the 20th, when nearly 50 mm fell: the total rainfall was 78.4 mm, some 97% of the Usk* average for September of 81.2 mm.
The month was cooler than average, with the mean maximum temperature of 17.8 °C being 1.4 °C below the Usk average for September of 19.2 °C. The highest was 24.4 °C on the 3rd and the lowest of a chilly 10.8 °C occurred on the 22nd.
* Usk is the nearest Met Office station for which long term averages (1981-2010) are available.
Day by day data for September are given below:-
MONTHLY CLIMATOLOGICAL SUMMARY for SEP. 2018 NAME: Penallt 210 CITY: STATE: ELEV: 210 m LAT: 51° 48' 00" N LONG: 2° 42' 00" W TEMPERATURE (°C), RAIN (mm), WIND SPEED (km/hr) HEAT COOL AVG MEAN DEG DEG WIND DOM DAY TEMP HIGH TIME LOW TIME DAYS DAYS RAIN SPEED HIGH TIME DIR ------------------------------------------------------------------------------------ 1 16.9 22.0 16:00 12.2 2:00 2.3 0.8 0.0 0.0 9.7 12:30 E 2 18.3 23.0 16:00 15.3 1:00 1.2 1.1 0.0 0.0 8.0 13:00 W 3 17.5 24.4 11:00 13.1 00:00 1.9 1.1 0.0 0.0 3.2 15:30 E 4 13.8 16.9 15:00 11.8 5:30 4.5 0.0 0.0 0.0 1.6 1:30 E 5 15.2 20.7 13:30 10.4 23:00 3.5 0.3 0.0 0.0 1.6 0:30 ESE 6 13.2 18.2 12:30 8.7 6:00 5.2 0.0 0.0 0.0 4.8 10:00 W 7 12.6 18.8 14:00 7.9 7:00 5.7 0.0 0.0 0.0 8.0 13:00 W 8 13.6 15.8 15:30 9.4 1:00 4.8 0.0 2.0 0.2 14.5 11:30 W 9 15.1 18.7 14:00 11.6 00:00 3.2 0.0 0.2 0.6 24.1 9:00 W 10 15.1 18.4 12:30 11.3 2:30 3.3 0.0 0.0 0.5 17.7 14:30 W 11 16.3 17.9 12:30 13.4 00:00 2.1 0.0 2.0 1.0 24.1 0:30 W 12 12.4 15.7 17:00 9.1 00:00 5.9 0.0 1.2 0.0 6.4 20:30 W 13 12.8 18.3 12:00 6.3 4:30 5.6 0.0 0.0 0.0 8.0 13:00 W 14 13.5 17.7 15:00 10.2 2:30 4.8 0.0 0.0 0.2 16.1 16:00 W 15 14.1 18.0 14:30 10.8 5:30 4.3 0.0 0.0 0.0 9.7 10:30 W 16 15.6 18.5 14:00 12.6 5:30 2.8 0.0 3.8 1.3 19.3 10:30 W 17 17.2 19.4 17:00 15.1 23:30 1.2 0.1 0.4 1.4 16.1 7:30 E 18 16.7 18.3 17:00 14.8 9:00 1.7 0.0 2.2 3.2 32.2 8:30 W 19 15.5 19.4 12:00 11.6 00:00 2.9 0.1 0.6 2.7 27.4 12:00 W 20 14.3 17.3 18:30 11.3 1:00 4.1 0.0 48.4 2.9 37.0 22:00 W 21 11.5 15.4 14:30 7.4 6:30 6.8 0.0 0.0 1.6 25.7 0:30 W 22 9.6 10.8 0:30 8.9 21:00 8.7 0.0 10.4 0.2 11.3 10:30 E 23 8.9 13.4 14:30 6.8 10:00 9.4 0.0 7.2 0.0 8.0 9:00 E 24 9.8 15.8 14:30 5.3 7:30 8.6 0.0 0.0 0.0 3.2 3:30 E 25 10.7 15.8 14:30 4.7 7:30 7.6 0.0 0.0 0.3 12.9 12:30 WSW 26 14.1 19.1 14:00 8.8 1:30 4.3 0.1 0.0 0.0 8.0 8:30 W 27 15.4 20.9 16:30 11.1 23:00 3.4 0.4 0.0 0.0 9.7 14:30 W 28 11.2 15.6 13:00 6.8 00:00 7.1 0.0 0.0 0.0 11.3 13:30 E 29 9.8 16.2 15:00 3.8 7:30 8.6 0.0 0.0 0.0 9.7 15:00 W 30 10.1 14.4 13:00 5.9 3:30 8.3 0.0 0.0 0.0 8.0 14:30 W ------------------------------------------------------------------------------------- 13.7 24.4 3 3.8 29 143.6 4.1 78.4 0.5 37.0 20 W Max >= 32.0: 0 Max <= 0.0: 0 Min <= 0.0: 0 Min <= -18.0: 0 Max Rain: 48.41 ON 20/09/18 Days of Rain: 11 (> .2 mm) 7 (> 2 mm) 1 (> 20 mm) Heat Base: 18.3 Cool Base: 18.3 Method: Integration