January 2019 Climate summary, statistics and data for West Rockville Maryland
JANUARY 2019 MONTHLY SUMMARY ROCKVILLE 2.8 WNW MARYLAND
by Kevin Shaw, Observer
January 2019 was a bit warmer and wetter than normal, based on new normals for my station developed out of the PRISM program out of Oregon State Univ. My max temp (40.2°) was 1.1° below normal but my min temp (26.8°) was 2.3° above normal, resulting in my mean temperature (33.5°) to be 0.6° above normal. My total precipitation of 3.92″ was 1.01″ above the newly computed normal precipitation January value for my station of 2.91”. Monthly total snowfall was 14.9”, helping to lessen the effect on my seasonal snowfall total that was depressed by my 0” December snowfall amountt. Snow normals are not computed by PRISM that I know of but I believe this January amount is a bit above normal for the month.
There were two really oold days during the month (maximums on the 21st with 19.5° and on the 31st with 20.8°). Mins in the single digits wee only found on the last two days of the month with 8.1° on the 30th and 6.3° on the 31st.
There were 13 days with measurable precipitation, highlighted by the monthly maximum of 1.18″ on the 24th accompanied by my monthly lowest pressure reading of 29.43” It was a brief warm storm in the middle of what was otherwise a dry last third of the month. Just two days prior to this storm, the highest pressure reading of the month occurred, a rather significant but not really that unusual 30.78” on the 22nd. With only 2 days between our highest and lowest pressure values for the month, it is only natural that it was a rather windy period also. Our biggest snowfall of the month was the storm on the 12th-13th when 11.5” of snow fell over that weekend. One other notable day of the month was on New Year’s Day, when the warmest temperature of the month was reached (59.8°). Other notable precipitation days included one more on a weekend on the 19th-20th when 1.28” of rain fell, and the weekend before when 0.81”” melted fell during my big monthly snowstorm.
The highest dew point temperature reached during the month was 56° on the 1st while the lowest dew point temperature value reached during the month was a rather significant – 11° reading on the 31st. There was a total of four days (20th-21st and 30th-31st) with below zero dew points during the month.
January had 11 cloudy days, 12 partly cloudy days, and 8 clear/sunny days. There were 976 heating degree days and 0 cooling degree days during the month. There were 7 foggy days, 6 windy days, and 8 days with snowfall during the month. The windy day category is subjective with no personal real data values to back it, just based on my descriptive email daily weather posts that are posted on weathertogether.net.
Daily max/min temperatures varied more than they did in December. My maximum temperature frequencies included 6 days between 50° and 59°, 7 days between 40° and 49°, 15 days between 30° and 39°, 2 days between 20° and 29° and 1 day below 20°. On the minimum temperature frequency side of things, there were 2 days below 10°, 4 days between 10° and 19°, 13 days between 20° and 29°, 10 days between 30° and 39°, and 2 days between 40° and 49°. The coldest daily max temperature was 19.5° on the 21st while the warmest daily min temp of 42.5° was on the 5th.
The diurnal range daily monthly average was 13.4° (- 3.4°). Our greatest daily range of temperature was 26.7° on the 20th, formed from a high of 41.7° and the low of 15.0°. We had a total of only 4 days with daily ranges above 20.0°. Our lowest range of temperature was 3.0° (29.9°-26.9°) on the 13th during our biggest snowfall day of the month. There were a significantly above normal 11 total days with diurnal temperature ranges of less than 10.0° throughout the month. A few significant all day precipitation events that held the daily variation to low values and also low sun angle helped to suppress this month’s daily diurnal ranges.
Fortunately I’ve had no more problems with my VP2 weather station as I did earlier in the year. I am constantly checking on my data quality frequently, along with discussion and data comparison with several of my Maryland weather cohorts and reliable online close-by observer data locations. I have made use of a snow stake placed in the ground just below and out from my balcony that I can read easily with the help of binoculars to help supplement my new snow and snow on the ground amounts when it is too dangerous to go out to my snowboard as often as I would like to. I continue to occasionally (as time allows) submit GLOBE Cloud observations, complete with submission of sky pictures at the time of the observation, usually timed with the passage of satellites and/or solar noon (about 70 minutes past actual EDT noon). Please ask me any questions you want at any time about my station setup and/or my data through any means available to you.
JANUARY 2019 – ROCKVILLE 2.8 WNW MARYLAND – SUMMARY STATISTICS
Average high temperature 40.2° (- 1.1°)
Average low temperature 26.8° (+ 2.3°)
Mean temperature 33.5° (+ 0.6°)
Precipitation 3.92″ (+1.01”)
Greatest daily amount (date) 1.18″ (24)
Greatest storm total (dates) 1.28” (19-20)
2019 year-to-date precipitation total 3.92″ (+1.01”)
Snowfall 14.9”
Greatest daily amount (date) 9.7″ (13)
Greatest storm total (dates) 11.5” (12-13)
Seasonal snowfall total 17.0″
High temperature for the month (date) 59.8° (1)
Low temperature for the month (date) 6.3° (31)
Highest barometric pressure (date) 30.78” (22)
Lowest barometric pressure (date) 29.33” (20)
Peak wind gust (date/direction): N/A
Heating degree days for the month: 976
Cooling degree days for the month: 0
Greatest diurnal range (date): 26.7° (20)
Least diurnal range (date) 3.0° (13)
Number of days:
Fog 7
Windy 6
Snow 8
Cloudy 11
Partly Cloudy 12
Sunny/Clear 8
Max temp ≥ 50° 6
Max temp =< 32° 4
Min temp =< 32° 22
Precip ≥ 0.01” 13
Excel spreadsheet data file for station in January 2019