NOVEMBER 2017 – CLIMATE STATISTICS 

Average high temperature 54.6°
Average low temperature 37.8°
Mean temperature 46.2°

Precipitation 2.04″
Greatest daily amount(date) 0.95″ (7)
Snow 0.0″
Year to date precipitation 37.76″

High temperature for the month (date) 72° (3)
Low temperature for the month (date) 23° (11)

Highest barometric pressure (date) 30.67” (11)
Lowest barometric pressure (date) 29.30” (19)

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

Heating degree days for the month: 564
Cooling degree days for the month: 0

Greatest diurnal range (date): 35.2° (18)
Least diurnal range (date) 7.1° (5)

Number of days:

Fog 4
Thunder 0
Cloudy 8
Partly Cloudy 13
Sunny/Clear 9
Max temp => 70° 2
Min temp =< 32° 6

NOVEMBER 2017 CLIMATE SUMMARY

November 2017 was significantly drier than normal with near normal temperatures, according to the NWS PRESTO November 2017 publication. The 2.04″rain that did fall all month was mostly concentrated in the first part of the month, as over 84% of the month’s total precipitation fell on 4 straight days between the 4th and 7th (1.72″). There was a total of 8 days of measurable rain. No snow fell. Temperatures fell slowly through the month as would be expected for November, with a most notable cold snap from the 10th – 12th that marked our first freeze of the season. It is very unusual to have the first freeze to occur at the same time throughout the region.

A brief warm period occurred at the beginning of the month on the 2nd and 3rd, with maximum temperatures recorded in the low 70s. Minimum temperatures recorded in the low-mid 50s occurred on the 3rd, 5th and 6th. Our highest barometric pressure reading of the month (30.67″) occurred on the 11th, coincidentally on our coldest day of the month. Our lowest barometric
pressure reading of the month (29.30″) occurred on the 19th on one of our lighter rainy days during the month. We had 6 days with freezing minimums (probably a good bit below normal). There were 9 clear days, 13 partly cloudy days, and 8 cloudy days during the month. Not really
a month of many extremes though DCA and IAD came close to record low temps on November 11. Whether that is any indication for the rest of the winter remains to be seen.

There were 564 heating degree days (HDD) and 0 cooling degree days (CDD) during the month. There were 4 days of fog during the month, but no days with thunder as best I know of.

My maximum temperature frequencies included 2 days between 70° and 79°, 3 days between 60° and 69°, 16 days between 50° and 59°, 8 days between 40° and 49° and 1 day below 40°. On the minimum temperature frequency side of things, there was 6 days between 20° and 29°,13 days between 30° and 39°, 8 days between 40° and 49°, and 3 days between 50° and 59°. The coolest daily max temp was 37.0° on the 11th and warmest daily min temp was 53.6° on the 3rd.

The diurnal range daily monthly average was 16.8°. Our greatest daily range of temperature was 35.2°, formed from a high of 60.3° and low of 25.1° on a mostly sunny day on the 18th. There were 8 days total with daily ranges at or above 20.0°.while our lowest range of temperature was 7.1° on a lightly rainy day on the 5th, formed from a high temperature of 58.5° and a low temperature of 51.4°. There were only a total of 3 days with minimum diurnal
temperature ranges less than 10.0°, a decrease of 2 over last month.

With yet another month to study the instrument changes made in mid-August,  data appears to be stable and an overall data quality improvement success. I am still constantly checking on my data quality frequently along with some of my Maryland weather cohorts. Winterizing of the gauges has mostly taken place. Marty and I established a good location for the snowboards, and they have already been put to use with a few light snows occurring so far in December. I haven’t decided whether or not to move my cocorahs rain gauge closer to the building to ease efforts for winter reading, especially during icy/snowy periods. I have some spikes to put on my shoes that so far have worked on a few icy street, sidewalk, and slippery snow/ice-on-grass occurrences when traveling to and from my rain gauge. I now only have the outer cylinder in place on my cocorahs gauge to minimize freezing of some of the parts of the gauge, and to better catch snow for water equivalent purposes. Within the past week Marty brought over a “snow stake” that we plunged into the ground near the flagpoles so that with binoculars I can read the general snowfall accumulation from my balcony. We shall see how that works out. I still will go out to the snowboard as long as it is safe to take official measurements. Please ask me
any questions you want at any time about my station setup and/or my data through any means available to you.