OCTOBER 2017 – CLIMATE SUMMARY – ROCKVILLE 2.8 WNW MARYLAND

October 2017 was warm and relatively dry. Warm minimum temperatures once again dominated the trends most of the month. Once again, as has been the pattern over the past several years, our first freeze of the season was not recorded in October. Fall foliage changes once again were just really getting in gear at the end of October and peak color was not reached till about November 10. Colder air at the end of the month, highlighted by the storm on the 29th, finally started to accelerate the color change. Temperatures remained warm for most of the month, through the 24th during which I had 16 days with max temperatures over 70°, including 4 days of 80° or more during the month’s “heat wave” between the 5th and 10th. The highest reading was 82.8° on the 9th. The highest min of the month was recorded on the 8th with a sultry, summerlike 73° reading. The last week of the month cooled us off some, with high readings mostly in the 50s and 60s, and our only sub 40° min of the month on the morning of the 27th when 37.9° was reached. On the precipitation side of the ledger,  there were only 9 days with measurable precipitation, all days under an inch, with 2.52″ of rain falling during two short periods, from the 8th-12th (1.36″) and 29th-30th (1.16″) that comprised over 88% of the total monthly rainfall amount of 2.85”. On the 9th (0.56”) the rain that fell was from the remnants of Tropical Storm Nate, one of the two muggiest days of the month with dew point temperatures remaining above 70° all day (along with the 8th). The rainiest day of the month was during the non-tropical storm on the 29th (0.96″) and also was the day when the lowest barometric pressure reading of the month was reached (29.20″) at 2119. There was a rather sharp drop of 0.08″ in ten minutes to that lowest reading, then a 10 minute .06″ rise immediately thereafter. Some experts I consulted with said that this occurrence may have been a gravity wave. The highest pressure reading, conversely, was at the beginning of the month on the 3rd, when 30.61″ was recorded, a few days before our big heat wave.

There were 180 heating degree days (HDD) and 52 cooling degree days (CDD) during the month. There were 7 days of fog during the month, but no days with thunder as best I know of.

My maximum temperature frequencies included 4 days between 80° and 89°, 12 days between 70° and 79°, 11 days between 60° and 69°, and 4 days between 50° and 59°. On the minimum temperature frequency side of things, there was 1 day between 30° and 39°, 13 days between 40° and 49°, 10 days between 50° and 59, 5 days between 60° and 69° and 2 days between 70° and 79°. The coolest daily max temp was 55.4° on the 30th and warmest daily min was 73° on the 8th.

The diurnal range daily monthly average was 16.9°. The maximum daily range of 34.7° occurred on the 19th (78.0°- 43.3°). There were 10 days total with daily ranges at or above 20.0°. The lowest daily temperature range of 4.8° (62.0°- 57.2°) occurred on the 13th.There were a total of 5 days with minimum diurnal temperature ranges less than 10.0°, an increase of 2 per month over the previous 2 months. 

With another month to study the instrument changes made in mid-August, it appears to be a data quality improvement success. Time to winterize the gauges. My friend Marty brought over two snowboards that will hopefully get put to good use in the coming months. I still haven’t made any decisions as to where to place my snowboards and whether or not to move my cocorahs rain gauge closer to the building to ease efforts for winter reading, especially during icy/snowy periods. As far as I know apartment management has turned off the sprinklers now that we have had a killing freeze and the greenery has mostly turned brown. Please ask me any questions you want at any time about my station setup and/or my data through LIVE CHAT or other messaging means here on Weather Together.

Thank you!!

OCTOBER 2017 – ROCKVILLE 2.8 WNW MARYLAND CLIMATE STATISTICS 

Average high temperature 69.3°
Average low temperature   52.4°
Mean temperature              60.9°

Precipitation                           2.85″
Greatest daily amount(date)   0.96″ (29)
Snow                                       0.0″
Year to date precipitation    35.72″

High temperature for the month (date)    83° (9)
Low temperature for the month (date)     38° (27)

Highest barometric pressure (date)     30.61”  (3)
Lowest barometric pressure (date)      29.20” (29)

Peak wind gust (date/direction):               N/A

Heating degree days for the month:         180
Cooling degree days for the month:           52

Greatest diurnal range (date):                34.7° (19)
Least diurnal range (date)                        4.8° (13)

Number of days:

Fog                        7
Thunder                0
Cloudy                  10
Partly Cloudy        11
Sunny/Clear         10
Max temp => 70°  16
Min temp < 40°      1