Station Overview Station Location
Station Number MD-MG-120 Latitude 39.152611
Station Name Poolesville 5.4 W Longitude -77.509722
County Montgomery Elevation (ft) 231



Month 30 Yr Avg by PRISM Total Prcp Sum Days Covered By All Observations Daily Prcp Sum Daily Observation Count Multiday Prcp Sum Days Covered by Multiday Observations Multiday Observation Count Days With Prcp Days With Trace Total Snowfall Days With Snowfall Days With Snow On Ground
Oct 17 3.19 0.00 0 0.00 0 0.00 0 0 0 0 0.0 0 0
Nov 17 3.40 1.60 29 1.60 27 0.00 2 1 8 2 0.0 0 0
Dec 17 2.94 0.77 30 0.77 30 0.00 0 0 8 2 3.1 3 3
Jan 18 2.58 0.89 28 0.72 23 0.17 5 1 5 3 0.1 1 1
Feb 18 2.53 2.25 22 2.25 22 0.00 0 0 11 2 0.0 0 0
March 18 3.52 1.03 31 1.03 29 0.00 2 1 8 4 0.0 0 0
April 18 3.32 4.31 30 2.20 20 2.11 10 3 7 0 0.0 0 0
May 18 4.46 7.70 30 7.70 28 0.00 2 1 15 1 0.0 0 0
June 18 3.77 6.62 30 6.62 24 0.00 6 3 13 0 0.0 0 0
July 18 3.65 6.99 31 6.99 31 0.00 0 0 12 1 0.0 0 0
Aug 18 3.22 6.64 31 3.60 24 3.04 7 1 13 1 0.0 0 0
Sept 18 3.89 10.84 30 10.84 30 0.00 0 0 18 1 0.0 0 0
Water Year Totals: 40.47" 49.64" 322 days 44.32" 288 5.32" 34 days 11 118 days 17 days 3.2" 4 days 4 days



Days in Water Year Cell Color Key
        Daily Observation with Prcp         Missing Day
        Multiday Observation         Daily/Multiday Observation Conflict

Day of Year Daily Prcp Multiday Prcp
10/1/2017
10/2/2017
10/3/2017
10/4/2017
10/5/2017
10/6/2017
10/7/2017
10/8/2017
10/9/2017
10/10/2017
10/11/2017
10/12/2017
10/13/2017
10/14/2017
10/15/2017
10/16/2017
10/17/2017
10/18/2017
10/19/2017
10/20/2017
10/21/2017
10/22/2017
10/23/2017
10/24/2017
10/25/2017
10/26/2017
10/27/2017
10/28/2017
10/29/2017
10/30/2017
10/31/2017
11/1/2017 0.00
11/2/2017 T
11/3/2017 **
11/4/2017 0.00
11/5/2017 0.54
11/6/2017 0.02
11/7/2017 0.01
11/8/2017 0.80
11/9/2017 0.01
11/10/2017 0.02
11/11/2017 0.00
11/12/2017 0.00
11/13/2017 0.13
11/14/2017 0.00
11/15/2017 0.00
11/16/2017 T
11/17/2017 0.00
11/18/2017 0.00
11/19/2017 0.07
11/20/2017
11/21/2017 0.00
11/22/2017 0.00
11/23/2017 0.00
11/24/2017 0.00
11/25/2017 0.00
11/26/2017 0.00
11/27/2017 0.00
11/28/2017 0.00
11/29/2017 0.00
11/30/2017 0.00
12/1/2017 0.02
12/2/2017 0.00
12/3/2017 0.08
12/4/2017 0.00
12/5/2017 0.00
12/6/2017 0.15
12/7/2017
12/8/2017 0.00
12/9/2017 0.00
12/10/2017 0.12
12/11/2017 0.00
12/12/2017 0.00
12/13/2017 T
12/14/2017 0.00
12/15/2017 0.00
12/16/2017 0.02
12/17/2017 0.00
12/18/2017 0.00
12/19/2017 0.00
12/20/2017 0.00
12/21/2017 0.00
12/22/2017 0.00
12/23/2017 0.13
12/24/2017 0.19
12/25/2017 0.00
12/26/2017 0.00
12/27/2017 0.00
12/28/2017 T
12/29/2017 0.00
12/30/2017 0.06
12/31/2017 0.00
Day of YearDaily PrcpMultiday Prcp
1/1/2018 T
1/2/2018 0.00
1/3/2018 0.00
1/4/2018 0.01
1/5/2018 0.00
1/6/2018 0.00
1/7/2018 0.00
1/8/2018
1/9/2018 0.02
1/10/2018 0.00
1/11/2018 0.00
1/12/2018 0.10
1/13/2018 0.57
1/14/2018 T
1/15/2018 0.00
1/16/2018 0.00
1/17/2018 0.02
1/18/2018 0.00
1/19/2018
1/20/2018 0.00
1/21/2018 0.00
1/22/2018 0.00
1/23/2018
1/24/2018 0.00
1/25/2018 T
1/26/2018 **
1/27/2018 **
1/28/2018 **
1/29/2018 **
1/30/2018 0.17
1/31/2018 0.00
2/1/2018 0.00
2/2/2018 M
2/3/2018 0.00
2/4/2018 0.00
2/5/2018 M
2/6/2018 0.00
2/7/2018 0.03
2/8/2018 0.57
2/9/2018 0.00
2/10/2018 0.00
2/11/2018 0.75
2/12/2018
2/13/2018
2/14/2018 T
2/15/2018 0.06
2/16/2018 0.13
2/17/2018 0.08
2/18/2018 M
2/19/2018 M
2/20/2018 T
2/21/2018 0.00
2/22/2018 0.01
2/23/2018 0.14
2/24/2018 0.01
2/25/2018 0.44
2/26/2018 0.03
2/27/2018 0.00
2/28/2018 0.00
3/1/2018 0.00
3/2/2018 0.28
3/3/2018 T
3/4/2018 0.00
3/5/2018 0.00
3/6/2018 0.00
3/7/2018 0.07
3/8/2018 0.02
3/9/2018 0.00
3/10/2018 0.00
3/11/2018 0.00
3/12/2018 0.00
3/13/2018 T
3/14/2018 0.00
3/15/2018 0.00
3/16/2018 0.00
3/17/2018 T
3/18/2018 T
3/19/2018 0.00
3/20/2018 0.21
3/21/2018 **
3/22/2018 M
3/23/2018 0.00
3/24/2018 0.00
3/25/2018 0.00
3/26/2018 0.00
3/27/2018 0.00
3/28/2018 0.08
3/29/2018 0.14
3/30/2018 0.01
3/31/2018 0.22
Day of YearDaily PrcpMultiday Prcp
4/1/2018 0.00
4/2/2018 **
4/3/2018 **
4/4/2018 **
4/5/2018 **
4/6/2018 **
4/7/2018 0.03
4/8/2018 0.00
4/9/2018 0.00
4/10/2018 0.01
4/11/2018 0.00
4/12/2018 0.00
4/13/2018 0.01
4/14/2018 0.00
4/15/2018 0.00
4/16/2018 **
4/17/2018 1.84
4/18/2018 0.00
4/19/2018
4/20/2018 0.00
4/21/2018 0.00
4/22/2018 0.00
4/23/2018 0.00
4/24/2018 0.00
4/25/2018 0.79
4/26/2018 0.66
4/27/2018 0.68
4/28/2018 0.04
4/29/2018 0.01
4/30/2018 **
5/1/2018 **
5/2/2018 0.00
5/3/2018 0.00
5/4/2018 0.00
5/5/2018 T
5/6/2018 0.32
5/7/2018 0.05
5/8/2018 0.00
5/9/2018 0.00
5/10/2018 0.00
5/11/2018 0.10
5/12/2018 0.00
5/13/2018 0.25
5/14/2018 0.12
5/15/2018 1.34
5/16/2018 2.27
5/17/2018 0.78
5/18/2018 0.38
5/19/2018 1.11
5/20/2018 0.07
5/21/2018 0.00
5/22/2018 0.00
5/23/2018 0.48
5/24/2018 0.00
5/25/2018 0.00
5/26/2018
5/27/2018 0.00
5/28/2018 0.36
5/29/2018 0.01
5/30/2018 0.00
5/31/2018 0.06
6/1/2018 0.98
6/2/2018 0.19
6/3/2018 1.96
6/4/2018 **
6/5/2018 M
6/6/2018 0.02
6/7/2018 0.00
6/8/2018 0.00
6/9/2018 0.00
6/10/2018 0.03
6/11/2018 0.40
6/12/2018 0.04
6/13/2018 **
6/14/2018 0.00
6/15/2018 0.00
6/16/2018 0.00
6/17/2018 0.00
6/18/2018 0.00
6/19/2018 0.00
6/20/2018 0.56
6/21/2018 0.58
6/22/2018 0.12
6/23/2018 1.27
6/24/2018 0.10
6/25/2018 0.37
6/26/2018 0.00
6/27/2018 **
6/28/2018 0.00
6/29/2018 0.00
6/30/2018 0.00
Day of YearDaily PrcpMultiday Prcp
7/1/2018 0.00
7/2/2018 0.00
7/3/2018 0.00
7/4/2018 T
7/5/2018 0.05
7/6/2018 0.00
7/7/2018 0.01
7/8/2018 0.00
7/9/2018 0.00
7/10/2018 0.00
7/11/2018 0.00
7/12/2018 0.00
7/13/2018 0.00
7/14/2018 0.00
7/15/2018 0.00
7/16/2018 0.35
7/17/2018 0.00
7/18/2018 0.04
7/19/2018 0.00
7/20/2018 0.00
7/21/2018 0.00
7/22/2018 4.31
7/23/2018 0.21
7/24/2018 0.54
7/25/2018 0.21
7/26/2018 0.44
7/27/2018 0.01
7/28/2018 0.08
7/29/2018 0.00
7/30/2018 0.00
7/31/2018 0.74
8/1/2018 0.42
8/2/2018 **
8/3/2018 **
8/4/2018 **
8/5/2018 **
8/6/2018 **
8/7/2018 **
8/8/2018 3.04
8/9/2018 0.23
8/10/2018 0.00
8/11/2018 0.02
8/12/2018 0.07
8/13/2018 0.03
8/14/2018 0.01
8/15/2018 0.01
8/16/2018 0.00
8/17/2018 0.00
8/18/2018 0.17
8/19/2018 0.06
8/20/2018 T
8/21/2018 0.01
8/22/2018 2.54
8/23/2018 0.01
8/24/2018 0.00
8/25/2018 0.00
8/26/2018 0.00
8/27/2018 0.00
8/28/2018 0.00
8/29/2018 0.00
8/30/2018 0.00
8/31/2018 0.02
9/1/2018 1.16
9/2/2018 0.00
9/3/2018 0.00
9/4/2018 0.00
9/5/2018 0.00
9/6/2018 0.00
9/7/2018 0.00
9/8/2018 0.74
9/9/2018 1.09
9/10/2018 1.36
9/11/2018 0.30
9/12/2018 0.03
9/13/2018 0.02
9/14/2018 0.03
9/15/2018 0.02
9/16/2018 T
9/17/2018 0.00
9/18/2018 0.72
9/19/2018 0.07
9/20/2018 0.00
9/21/2018 0.00
9/22/2018 0.32
9/23/2018 0.14
9/24/2018 1.01
9/25/2018 0.63
9/26/2018 0.05
9/27/2018 1.19
9/28/2018 1.96
9/29/2018 0.00
9/30/2018 0.00



Observation Date Observation Time Precipitation Snowfall Snowfall SWE Snow Depth Snow SWE Notes
11/1/2017 7:00 AM 0.00 0.0 M M M
11/2/2017 7:30 AM T M M M M There were two periods of a Trace of rain: 1149-1202 and 1728-1735.
11/5/2017 7:15 AM 0.54 M M M M It is raining lightly. This is the first occasion with the add'l rain gauge whereby I can do a side-by-side comparison to my digital LaCrosse gauge, which measured 0.57".
11/6/2017 7:30 AM 0.02 M M M M
11/7/2017 7:30 AM 0.01 M M M M A bit of rain today around 1600.
11/8/2017 7:30 AM 0.80 M M M M Rain began at 1003 till 1011 for a trace. Then again it began in more earnest at 1039. There was typical street and field flooding, which is still remaining. Ground water is high. This rain gauge was next to the digital one, which reported 0.85" of rain. This is practically the first evaluation on the reporting data for the two gauges together.
11/9/2017 7:30 AM 0.01 M M M M It rained between 0550 and 0615. The ground is already saturated.
11/10/2017 7:30 AM 0.02 M M M M
11/11/2017 8:00 AM 0.00 0.0 M M M
11/12/2017 8:00 AM 0.00 0.0 M M M Frost this AM.
11/13/2017 7:30 AM 0.13 M M M M
11/14/2017 8:00 AM 0.00 0.0 M M M
11/15/2017 7:30 AM 0.00 0.0 M M M
11/16/2017 7:30 AM T M M M M
11/17/2017 7:30 AM 0.00 0.0 M M M
11/18/2017 7:30 AM 0.00 0.0 M M M Frost.
11/19/2017 7:30 AM 0.07 M M M M Rain occurred at two periods: 1) 0910-0913 for a Trace; 2) 1315-0341 on 11/19/17.
11/21/2017 6:30 AM 0.00 0.0 M M M Frost report.
11/22/2017 7:30 AM 0.00 0.0 M M M
11/23/2017 7:30 AM 0.00 0.0 M M M Frost report.
11/24/2017 7:30 AM 0.00 0.0 M M M Frost report.
11/25/2017 7:30 AM 0.00 0.0 M M M Frost report.
11/26/2017 7:30 AM 0.00 0.0 M M M
11/27/2017 7:30 AM 0.00 0.0 M M M
11/28/2017 7:30 AM 0.00 0.0 M M M Frost report.
11/29/2017 7:30 AM 0.00 0.0 M M M Frost.
11/30/2017 7:30 AM 0.00 0.0 M M M
12/1/2017 7:30 AM 0.02 M M M M Frost
12/2/2017 5:20 AM 0.00 0.0 M M M
12/3/2017 7:30 AM 0.08 M M M M
12/4/2017 7:00 AM 0.00 0.0 M M M Frost
12/5/2017 7:30 AM 0.00 0.0 M M M
12/6/2017 7:30 AM 0.15 M M M M
12/8/2017 7:30 AM 0.00 0.0 M M M
12/9/2017 7:30 AM 0.00 0.0 M M M NO snow or any pptn yet.
12/10/2017 7:30 AM 0.12 2.5 0.12 2.5 0.12 I measured the snow at 1600 at 2.2" (actually 2.25"). It stopped sometime before 2000.
12/11/2017 7:30 AM 0.00 0.0 M M M
12/12/2017 7:30 AM 0.00 0.0 M M M
12/13/2017 6:30 AM T 0.0 M M M Blowing pptn from the west.
12/14/2017 7:30 AM 0.00 0.0 M M M
12/15/2017 7:30 AM 0.00 0.0 M M M
12/16/2017 8:00 AM 0.02 0.1 0.02 0.1 0.02 Flurries began at 0919 for 10 min or less. Snow began at 1130 and came down for a while, stopping before 1600, when I measured its depth. The snow was round balls. See snowflake report.
12/17/2017 7:30 AM 0.00 0.0 M M M Frost report.
12/18/2017 7:30 AM 0.00 0.0 M M M
12/19/2017 7:15 AM 0.00 0.0 M M M
12/20/2017 7:30 AM 0.00 0.0 M M M
12/21/2017 7:30 AM 0.00 0.0 M M M Frost report.
12/22/2017 7:30 AM 0.00 0.0 M M M
12/23/2017 8:00 AM 0.13 M M M M Slight fog.
12/24/2017 8:00 AM 0.19 M M M M Rain began exactly at 0939 and continued throughout the whole day, ending before 1800.
12/25/2017 8:00 AM 0.00 0.0 M M M
12/26/2017 7:30 AM 0.00 0.0 M M M It was an extremely windy day with some large tree branches down on River Road and White's Ferry Road from White's Ferry east to Poolesville. Wind gusts over 10 MPH were nearly constant at 5-minute interval recordings between 0415 and 1550. There were gusts frequently over 20 MPH. Max wind gust was 34 MPH at 0710 yesterday.
12/27/2017 7:30 AM 0.00 0.0 M M M No pptn yet, as was forecasted.
12/28/2017 7:30 AM T T T T T Only trace of snow today. There was nothing to melt.
12/29/2017 7:30 AM 0.00 0.0 M M M Frost report.
12/30/2017 7:30 AM 0.06 0.5 0.06 0.5 0.06 It snowed some time between 0300 and 0600.
12/31/2017 7:30 AM 0.00 0.0 M M M
1/1/2018 7:30 AM T T T T T Very brief snow flurries. Temp this AM is a very cold 5°F. Frost report.
1/2/2018 7:30 AM 0.00 0.0 M M M
1/3/2018 7:30 AM 0.00 0.0 M M M Frost report. Another 5 degree AM.
1/4/2018 8:00 AM 0.01 T 0.01 T 0.01 There was only a dusting of snow. It stopped before 0700.
1/5/2018 7:30 AM 0.00 0.0 M M M
1/6/2018 7:30 AM 0.00 0.0 M M M
1/7/2018 7:30 AM 0.00 0.0 M M M Frost report.
1/9/2018 7:30 AM 0.02 M M M M Frost report. A light fog at 0700 due west <1/4 mile from the Potomac River. Freezing rain 1208 - ~1220. Rain that froze on the ground 1611 - after 1800.
1/10/2018 7:30 AM 0.00 0.0 M M M Frost report.
1/11/2018 7:30 AM 0.00 0.0 M M M
1/12/2018 7:30 AM 0.10 M M M M
1/13/2018 7:30 AM 0.57 M M M M Light blowing rain about 1015 for a few minutes. Then more blowing rain about 1600. Per the digital LaCrosse rain gauge, pptn began (temp was in the 60s) at 0300 till 0405 and spuringly till 0820. The same rain gauge did not pick up any rain until 1905. Then again beginning about 2300 for an hour or so at a rate of 0.01-0.02" per 5 minutes. The last was recorded at 0150.
1/14/2018 8:00 AM T T T T T Very light flurries. Frost report.
1/15/2018 7:30 AM 0.00 0.0 M M M Frost report.
1/16/2018 7:30 AM 0.00 0.0 M M M
1/17/2018 8:00 AM 0.02 0.1 0.02 0.1 0.02 Snow stopped sometime before 0700.
1/18/2018 7:30 AM 0.00 0.0 M M M Frost report.
1/20/2018 7:30 AM 0.00 0.0 M M M
1/21/2018 8:00 AM 0.00 0.0 M M M
1/22/2018 7:00 AM 0.00 0.0 M M M
1/24/2018 7:30 AM 0.00 0.0 M M M
1/25/2018 7:30 AM T T T T T Very light flurries.
1/31/2018 7:30 AM 0.00 0.0 M M M
2/1/2018 7:30 AM 0.00 0.0 M M M
2/2/2018 8:00 AM M M M M M Frost report.
2/3/2018 7:30 AM 0.00 0.0 M M M
2/4/2018 7:15 AM 0.00 0.0 M M M
2/5/2018 8:00 AM M M M M M
2/6/2018 7:30 AM 0.00 0.0 M M M Frost report.
2/7/2018 8:00 AM 0.03 M M M M It was not raining when the measurement was taken nor at the time of this report. All the rain turned to a layer of ice. The pptn reported may actually be less because there were drops of water all over the side of the large cylinder.
2/8/2018 8:00 AM 0.57 M M M M The rain was solid ice and needed to be warmed up with measured water.
2/9/2018 7:30 AM 0.00 0.0 M M M Frost report.
2/10/2018 7:30 AM 0.00 0.0 M M M Frost report. Flooding is expected with the impending rain for the next few days.
2/11/2018 8:00 AM 0.75 M M M M It has been raining all night and is raining steadily now.
2/14/2018 8:00 AM T M M M M Light showers began three times yesterday: 1429-1437, 1527-1531 and 1706 till (?), very short time as there was only a trace of pptn collected.
2/15/2018 7:30 AM 0.06 M M M M Fog with visibility to 350 feet.
2/16/2018 7:30 AM 0.13 M M M M Rain has stopped.
2/17/2018 7:30 AM 0.08 M M M M
2/18/2018 7:30 AM M M M M M See MD-MG-103 for the amounts of snow and melted snow.
2/19/2018 7:30 AM M M M M M It rained over night, but the CoCoRaHS rain gauges and my LaCrosse digital rain gauge was inoperable.
2/20/2018 7:30 AM T M M M M
2/21/2018 7:30 AM 0.00 0.0 M M M There was a slight fog at 0700 to the west and the Potomac River.
2/22/2018 8:00 AM 0.01 M M M M It rained sometime between 1730 and 2000.
2/23/2018 7:30 AM 0.14 M M M M
2/24/2018 7:30 AM 0.01 M M M M Fog limited visibility to about 500 feet.
2/25/2018 8:00 AM 0.44 M M M M
2/26/2018 7:30 AM 0.03 M M M M
2/27/2018 7:00 AM 0.00 0.0 M M M Fog visibility 500 feet. Frost report.
2/28/2018 7:30 AM 0.00 0.0 M M M
3/1/2018 7:30 AM 0.00 0.0 M M M
3/2/2018 8:00 AM 0.28 T T T T Very light, blowing flurries. Today at 0800. The rain was yesterday for about 2 hours max.
3/3/2018 8:00 AM T T T T T There was lightly blowing flurries between 0800 and 0830. Extremely windy day with max wind gusts of 42.5 MPH at 1404.
3/4/2018 7:30 AM 0.00 0.0 M M M
3/5/2018 7:00 AM 0.00 0.0 M M M
3/6/2018 8:00 AM 0.00 0.0 M M M Frost report.
3/7/2018 8:00 AM 0.07 M M M M
3/8/2018 7:30 AM 0.02 T T T T Light rain began at 0905, then turned to sleet and snow for a few minutes. It stopped before 1130.
3/9/2018 7:30 AM 0.00 0.0 M M M
3/10/2018 7:30 AM 0.00 0.0 M M M Frost report.
3/11/2018 7:30 AM 0.00 0.0 M M M Frost report.
3/12/2018 7:30 AM 0.00 0.0 M M M
3/13/2018 7:30 AM T T T T T Light blowing flurries just after 2115. I was in Darnestown and Poolesvile between 2050 and 2110.
3/14/2018 8:00 AM 0.00 0.0 M M M
3/15/2018 7:30 AM 0.00 0.0 M M M
3/16/2018 7:30 AM 0.00 0.0 M M M
3/17/2018 7:30 AM T T T T T Light flurries.
3/18/2018 7:30 AM T T T T T Fluries: 1349-1355; 1414-1630
3/19/2018 7:30 AM 0.00 0.0 M M M Frost report
3/20/2018 7:30 AM 0.21 M M M M Freezing rain and ice pellets. Observation occurred at the designated time but I had internet issues to report earlier.
3/23/2018 7:30 AM 0.00 0.0 M M M
3/24/2018 8:00 AM 0.00 0.0 M M M Frost Report
3/25/2018 7:30 AM 0.00 0.0 M M M
3/26/2018 7:30 AM 0.00 0.0 M M M Frost report.
3/27/2018 7:30 AM 0.00 0.0 M M M
3/28/2018 8:00 AM 0.08 M M M M
3/29/2018 7:30 AM 0.14 M M M M Light fog around 0700.
3/30/2018 8:00 AM 0.01 M M M M It began raining exactly at 0800.
3/31/2018 7:30 AM 0.22 M M M M Frost report. There was a trace of rain between 0800 when it started till ~0820. Then rain began at 1110 and continued heavily for several minutes and stopped about 1155.
4/1/2018 7:30 AM 0.00 0.0 M M M
4/8/2018 8:00 AM 0.00 0.0 M M M
4/9/2018 7:30 AM 0.00 0.0 M M M
4/10/2018 7:30 AM 0.01 T 0.01 T 0.01 Snow began at 0750 and stopped before 0945. Rain began at 1355 and continued off and on all afternoon into the early evening. Frost and Fog reports.
4/11/2018 7:30 AM 0.00 0.0 M M M
4/12/2018 8:00 AM 0.00 0.0 M M M
4/13/2018 8:00 AM 0.01 M M M M
4/14/2018 7:30 AM 0.00 0.0 M M M
4/15/2018 7:30 AM 0.00 0.0 M M M
4/18/2018 7:30 AM 0.00 0.0 M M M Frost report.
4/20/2018 7:30 AM 0.00 0.0 M M M
4/21/2018 7:30 AM 0.00 0.0 M M M
4/22/2018 7:30 AM 0.00 0.0 M M M
4/23/2018 7:30 AM 0.00 0.0 M M M
4/24/2018 7:30 AM 0.00 0.0 M M M
4/25/2018 7:45 AM 0.79 M M M M The lower lying farm fields are flooded and water run off is going down River Road. Rain has stopped for now.
4/26/2018 7:30 AM 0.66 M M M M Rain began at 1112 and stopped sometime before 1730. Flooding of the road was fair - water is still going down the road on both sides due to farm field run off. There are still spots of water in the farm fields.
4/27/2018 7:30 AM 0.68 M M M M It is still drizzling during this recording. There is lots of water on the farm fields and it is draining on the road.
4/28/2018 7:30 AM 0.04 M M M M Fog
4/29/2018 7:30 AM 0.01 M M M M It rained for about 5 minutes at 1530 due to an overhead dark cloud.
5/3/2018 7:30 AM 0.00 0.0 M M M
5/4/2018 7:00 AM 0.00 0.0 M M M
5/5/2018 8:00 AM T M M M M I don't know when it stopped raining.
5/6/2018 7:30 AM 0.32 M M M M Besides rain beginning around 1635, it rained for 5 minutes at 1311.
5/7/2018 7:30 AM 0.05 M M M M 0600: Visibility 500 feet, west towards the Potomac River. Less fog eastward.
5/8/2018 7:30 AM 0.00 0.0 M M M Fog-visibility about 1000 feet at 0615.
5/9/2018 7:30 AM 0.00 0.0 M M M
5/10/2018 7:30 AM 0.00 0.0 M M M
5/11/2018 7:30 AM 0.10 M M M M Fog at 0515 with visibility to 1000'. Fog at 0515 with visibility to 1000'. There were three periods of rain: 1024-1110; 1415-1445; and 1638-1644, which was rather heavy.
5/12/2018 7:30 AM 0.00 0.0 M M M
5/13/2018 7:30 AM 0.25 M M M M At 1925 last night, I could see storm clouds due east across the Potomac River and the wind picked up a lot. This lasted for about 7 minutes. The only rain at this time as a Trace due to rain picked up by the blowing wind. There was a thunderstorm during the morning hours, 0420-0510.
5/14/2018 7:30 AM 0.12 M M M M Rain began in the AM stopped around 1000 and began around 2000 again till late at night. This is the first occasion with having two rain gauges that I recorded a difference of greater than 0.01".
5/15/2018 7:30 AM 1.34 M M M M Very light and blowing rain began at 1748 for about 10 minutes, then stopped. Across the Potomac River (westward, in VA, where the storms come from) had lots of continuous rolling thunder. The sky is very black there and I cannot see the trees just on the west bank of the Potomac due to the heavy rain. At 1805 rain began, then at 1811 the wind picked up. The wind gust was over 20 MPH. At 1812 the heavy rain began. By 2000 all the rain was nearly over. Per my tipping bucket digital rain gauge, rain began in the morning of 5/15 at 0220 till 0415. This rain was intense and the lightning and thunder was long and continuous in these early morning hours. Evidence of minor flooding and no trees were down around this location and River Road that I can see.
5/16/2018 7:30 AM 2.27 M M M M Most of the rain has drained off the fields. However, the torrential rain caused a lot of the gravel on River Road to be washed away and the sides of the road are dug deeper due to the amount of water flow. Based on previous rains of this intensity, River Road must have been 4-6" deep with water runoff.
5/17/2018 7:30 AM 0.78 M M M M It rained lightly almost all day, even when I took the gauge measurement yesterday morning.
5/18/2018 7:30 AM 0.38 M M M M There were three periods of recorded rain by the tipping bucket LaCrosse rain gauge: 0900-0915; 1250-1750; and 2345-0320. River Road is now pretty much destroyed by the rain.
5/19/2018 7:30 AM 1.11 M M M M It rained nearly all day yesterday and during the night.
5/20/2018 7:30 AM 0.07 M M M M There was light rain, off-and-on, nearly all day.
5/21/2018 7:30 AM 0.00 0.0 M M M
5/22/2018 7:30 AM 0.00 0.0 M M M
5/23/2018 7:30 AM 0.48 M M M M It was quite a day for rain activity. Rain Periods: + 0820-30 (not picked up by tipping bucket; + 0901-10 (not picked up by tipping bucket; + 1015-1100 0.14" by tipping bucket; + 1511-30: lots of rain, 0.36" in 19 minutes. There was a lot of water on White's Ferry Road, such that it was several inches deep flowing down the hills. Skywarn (MO-319) report due to excessive rain in a few minutes.
5/24/2018 7:30 AM 0.00 0.0 M M M
5/25/2018 7:30 AM 0.00 0.0 M M M
5/27/2018 7:30 AM 0.00 0.0 M M M See MD-MG-103 for 0.02" of rain, whereas this gauge got no rain! That's possible, because it must happen somewhere.
5/28/2018 7:30 AM 0.36 M M M M The ground is totally saturated.
5/29/2018 7:30 AM 0.01 M M M M
5/30/2018 7:30 AM 0.00 0.0 M M M
5/31/2018 8:00 AM 0.06 M M M M It was misting rain when this collection reading was taken. Rain began at 1410 as a Trace, then a bit harder at 2000 with occasional rain into the early morning hours.
6/1/2018 11:45 AM 0.98 M M M M This report was revised, because at 1145 I checked this gauge and it was 0.98". In the AM (0730), I guessed and did not check it completely. It had not rained since 0730 6/1.
6/2/2018 7:30 AM 0.19 M M M M 2140 could see thunderstorm activity in VA across the Potomac River with lots of thunder and lightning (cloud-to-cloud and ground-to-cloud). Just some wind here. At 2210 the storm activity had moved north towards Frederick, MD. At 2230 it began raining here. Flooding is typical water run-off from farm fields.
6/3/2018 7:30 AM 1.96 M M M M It was lightly raining when the measurements were taken. Skywarn report submitted. At 1711 very heavy rain began with wind and thunderclaps till 1738. During this time ~1.25" of rain was deposited. The rain was so heavy that I could not see the trees on this side of the C&O canal, about 1500 feet due west. Very light and light rain continued all night till this AM. There was also heavy rain about 2230 for a few minutes. The tipping bucket digital rain gauge did not record this rain. Total in the tipping bucket was 1.83". River Road was again destroyed by the moving water that displaced the gravel and creating many potholes. During the worst part of this storm, River Road was 5 inches deep at the road crest.
6/6/2018 7:30 AM 0.02 M M M M
6/7/2018 7:30 AM 0.00 0.0 M M M
6/8/2018 7:30 AM 0.00 0.0 M M M
6/9/2018 7:30 AM 0.00 0.0 M M M
6/10/2018 7:30 AM 0.03 M M M M SIGNIFICANT OBSERVATION ON RAIN and this area. Last night I was in Leesburg, VA, on Market Street by the shopping centers. Between 1930 and 2000 there was a large down pouring of rain for at least 10 minutes. When we left about 2015 it was lightly raining. While we were waiting for the ferry it was not raining on the VA side but we could clearly see the rain on the Potomac River. After we got to the MD shore, it was not raining, but it was still raining on the river as before. When we got home, there was only slight evidence of rain - 0.02". Nothing more came down over night. This AM at 0700 fog visibility was to 500 feet. The digital LaCrosse tipping bucket rain gauge, which is 8 feet south, reported 0.02".
6/11/2018 7:30 AM 0.40 M M M M There was a very slight sprinkle at 1435 yesterday. Cannot tell when the rain started during the night as the tipping bucket was not working. If it rains as it was forecasted, there will be some flooding. The ground it totally saturated at this time.
6/12/2018 7:30 AM 0.04 M M M M
6/15/2018 7:30 AM 0.00 0.0 M M M
6/16/2018 7:30 AM 0.00 0.0 M M M
6/17/2018 7:30 AM 0.00 0.0 M M M
6/18/2018 7:30 AM 0.00 0.0 M M M
6/19/2018 7:30 AM 0.00 0.0 M M M
6/20/2018 7:30 AM 0.56 M M M M 1330: 0.03"; 1350-1420: 0.47 1515: 0.01" 1655: 0.01". The timing is from the LaCrosse tipping bucket rain gauge.
6/21/2018 8:00 AM 0.58 M M M M Yesterday, while I was in Poolesville @1343 rain came down very heavily for about 10 minutes. When I got back to my residence, there was no sign of rain, except that both rain gauges showed 0.01" of pptn. Light rain began @1537 and ended by 1539. Again Light rain began at 1810 till 1820. Heaviest rain was at ~1900 for 15 minutes, then it tapered off till ~2100. (1900: 0.05"; 1905: 0.16"; 1910: 0.08".
6/22/2018 8:00 AM 0.12 M M M M It is raining somewhat heavily while I took the measurement.
6/23/2018 8:00 AM 1.27 M M M M It rained all day and it was misting while I took this AM's reading.
6/24/2018 8:00 AM 0.10 M M M M
6/25/2018 7:30 AM 0.37 M M M M
6/26/2018 7:30 AM 0.00 0.0 M M M
6/29/2018 7:30 AM 0.00 0.0 M M M
6/30/2018 7:00 AM 0.00 0.0 M M M
7/1/2018 7:30 AM 0.00 0.0 M M M
7/2/2018 7:30 AM 0.00 0.0 M M M
7/3/2018 7:30 AM 0.00 0.0 M M M
7/4/2018 7:30 AM T M M M M 1721 there was light blowing rain from the SE for no greater than 2 minutes. Thunder was heard toward the S and E.
7/5/2018 7:30 AM 0.05 M M M M There were two periods of rain during the previous 24 hours (0730-0730). The first was yesterday between 1920 and 2035. The second was today at 0700 for only a Trace.
7/6/2018 7:30 AM 0.00 0.0 M M M
7/7/2018 7:30 AM 0.01 M M M M There was light beginning at 0753, off-and-on till the early PM.
7/8/2018 7:30 AM 0.00 0.0 M M M 0645 - fog with visibility to 1000 feet.
7/9/2018 7:30 AM 0.00 0.0 M M M
7/10/2018 7:00 AM 0.00 0.0 M M M
7/11/2018 7:30 AM 0.00 0.0 M M M
7/12/2018 7:30 AM 0.00 0.0 M M M
7/13/2018 7:30 AM 0.00 0.0 M M M
7/14/2018 7:30 AM 0.00 0.0 M M M
7/15/2018 7:30 AM 0.00 0.0 M M M
7/16/2018 7:30 AM 0.35 M M M M Fog with visibility to less than 500' @0630. Light to moderate rain began as I was traveling westward toward home @1325. I was about 5 miles from home on White's Ferry Road. At home there was 0.11" of rain that was observed at 1343. Very loud thunder began at 1338 and occurred every few minutes afterwards with heavy rain beginning at 1359 from the N.
7/17/2018 7:00 AM 0.00 0.0 M M M Slight rain at 1527. There was thunder to the South and East, then it moved to the North and East, between 1515 and 1745. Nothing recorded at this rain gauge however.
7/18/2018 6:30 AM 0.04 M M M M There were three periods of rain and each time it was just a bit for a total of 0.05"/0.04" - 1215, 1300 and 2043.
7/19/2018 6:30 AM 0.00 0.0 M M M
7/20/2018 7:15 AM 0.00 0.0 M M M
7/21/2018 7:00 AM 0.00 0.0 M M M
7/22/2018 6:30 AM 4.31 M M M M Hardness rain was 0.45"/hour between 1335 and 1435. Otherwise it appeared to be 0.25"/hour beginning after midday. At 0940 it rained several drops for less than 5 minutes. Will report later when the rain stopped.
7/23/2018 7:00 AM 0.21 M M M M There was no rain yesterday out here, however south and east of here there was a lot of rain coming down. During the night it did rain between 0130 and 0430. At this time the rain began again very lightly with a few drops here-and-there. During the time I was taking the readings, I heard 4 thunder claps to the E, SE and S.
7/24/2018 7:00 AM 0.54 M M M M Heavy rain at this time.
7/25/2018 7:00 AM 0.21 M M M M
7/26/2018 7:00 AM 0.44 M M M M
7/27/2018 7:00 AM 0.01 M M M M Don't know whether the reading was due to pptn or dew, which is somewhat heavy.
7/28/2018 7:00 AM 0.08 M M M M
7/29/2018 7:30 AM 0.00 0.0 M M M
7/30/2018 7:00 AM 0.00 0.0 M M M
7/31/2018 7:30 AM 0.74 M M M M There was light rain between 1315 and 1350, then a more moderate and continuous rain was between 1545 and 1730.
8/1/2018 7:30 AM 0.42 M M M M There were two periods of rain. One at 1702-1705 left a Trace. Then during the night 0105 till 0420.
8/9/2018 7:30 AM 0.23 M M M M A heavy rain came in a very few minutes.
8/10/2018 7:30 AM 0.00 0.0 M M M
8/11/2018 7:30 AM 0.02 M M M M It rained in the early morning after it was light.
8/12/2018 7:00 AM 0.07 M M M M It rained 0.06" between 1521 and 1555. Then the last 0.01" happened over night or it is due to dew.
8/13/2018 7:00 AM 0.03 M M M M Fog at 0645, visibility lack of visibility to ~1000', westward toward the Potomac River only.
8/14/2018 7:30 AM 0.01 M M M M
8/15/2018 7:30 AM 0.01 M M M M Light rain.
8/16/2018 7:30 AM 0.00 0.0 M M M
8/17/2018 7:30 AM 0.00 0.0 M M M
8/18/2018 7:30 AM 0.17 M M M M There were thunderstorms during the night.
8/19/2018 7:00 AM 0.06 M M M M There were two periods of light rain: 0800-<0900; and 1730-<1830.
8/20/2018 7:30 AM T M M M M Slight rain at 1543.
8/21/2018 7:00 AM 0.01 M M M M Light rain, about 0630.
8/22/2018 7:00 AM 2.54 M M M M A major storm came through last night leaving over two inches of rain. Some of the 2.54" came during the day with off-and-on sprinkles beginning 0904. The heaviest rain began around 2050 till giving 1.37" in 20 minutes, then again at 2315, quitting around 2335, with the heaviest of 0.43" in 10 minutes. The flooding and destruction of the road occurs every time there is over one inch of rain.
8/23/2018 7:30 AM 0.01 0.0 M M M This may be from dew.
8/24/2018 7:00 AM 0.00 0.0 M M M Fog - visibility to about 500'.
8/25/2018 7:00 AM 0.00 0.0 M M M Fog with visibility about 1500'.
8/26/2018 7:30 AM 0.00 0.0 M M M
8/27/2018 7:30 AM 0.00 0.0 M M M Fog visibility to 1500 feet.
8/28/2018 7:00 AM 0.00 0.0 M M M Fog with visibility to 1500-2000 feet at 0615.
8/29/2018 7:30 AM 0.00 0.0 M M M Very light fog at 0615.
8/30/2018 7:30 AM 0.00 0.0 M M M
8/31/2018 7:30 AM 0.02 M M M M
9/1/2018 7:30 AM 1.16 M M M M Very large rain drops came down at 2030 for about 5-10 minutes. Then the rest of the rain began at 2045.
9/2/2018 7:30 AM 0.00 0.0 M M M
9/3/2018 7:30 AM 0.00 0.0 M M M There was 0.01" of pptn in the gauge, but I suspect it is due to dew. Fog visibility to 500'.
9/4/2018 7:30 AM 0.00 0.0 M M M
9/5/2018 7:30 AM 0.00 0.0 M M M Fog with visibility to 500 feet.
9/6/2018 7:30 AM 0.00 0.0 M M M Light fog.
9/7/2018 7:30 AM 0.00 0.0 M M M
9/8/2018 7:30 AM 0.74 M M M M For about 40 minutes before the rain came, there was thunder and lightning all around us.
9/9/2018 7:30 AM 1.09 M M M M It is raining medium to lightly as this measurement was taken.
9/10/2018 7:30 AM 1.36 M M M M It rained for most of the day. At the time of this recording there was a light breeze with drizzle from the ENE. Street flooding yesterday till early afternoon was enormous. River Road had 4" of water on it at the western end that parallels the canal-river during moderate and continuous rainfall. As the rain subsided, so did the flooded part of the road.
9/11/2018 7:30 AM 0.30 M M M M I rained lightly all day.
9/12/2018 7:30 AM 0.03 M M M M There was a light drizzle on-and-off throughout the day.
9/13/2018 7:30 AM 0.02 M M M M Very light drizzle.
9/14/2018 7:30 AM 0.03 M M M M Very light pptn in the air. Very light and occasional rain yesterday.
9/15/2018 7:30 AM 0.02 M M M M
9/16/2018 7:30 AM T M M M M Light rain at 1602-4 and 1633-5.
9/17/2018 7:30 AM 0.00 0.0 M M M
9/18/2018 7:30 AM 0.72 M M M M It rained off-and-on throughout the day.
9/19/2018 7:30 AM 0.07 M M M M Rain began medium force at 1019 till 1034. It rained a bit later before noon then in the evening again.
9/20/2018 7:30 AM 0.00 0.0 M M M A light ground level fog exits at 0600 and dropped by 0700 with partial visibility to 1000'.
9/21/2018 7:30 AM 0.00 0.0 M M M
9/22/2018 7:30 AM 0.32 M M M M It rained about 0400. This location had 0.07" more than MD-MG-103.
9/23/2018 7:30 AM 0.14 M M M M There were several periods when it rained lightly: 1244-1250; 1517-1530; 1620-1645 on 9/22 and 0315 lightly, then harder at 0535 and continued on 9/23.
9/24/2018 7:45 AM 1.01 M M M M It rained nearly all day.
9/25/2018 7:30 AM 0.63 M M M M It began raining as I took the measurement.
9/26/2018 8:00 AM 0.05 M M M M There was light rain off-and-on during the day.
9/27/2018 7:30 AM 1.19 M M M M NOTE: THIS MEASUREMENT IS ACCURATELY 0.16" GREATER THAN MD-MG-103! At 1759 the rain began lightly and as I looked westward toward the Potomac River, the rain was coming down so fiercely that visibility was limited to about 500'. Then at 1801, we received that torrential downpour. SKYWARN report submitted. Throughout the day there was an occasional dribble of rain now and then. As for River Road, the gravel road was again torn up by the rain coming from the fields. What's interesting is that the road was already full of pot holes and the county came by yesterday, beginning to add more gravel and to level it out. Nearly all their work is destroyed. There is one 6"deep x 1' wide pot hole completely across the road where water flowed from a blocked culvert.
9/28/2018 7:30 AM 1.96 M M M M See MD-MG-103 for details.
9/29/2018 7:30 AM 0.00 0.0 M M M There was 0.01" of water in the gauge, but I suspect this was due to dew from the fog early this AM.
9/30/2018 7:30 AM 0.00 0.0 M M M



Start Date End Date & Time Duration in Days Precipitation Snow Depth Snow Depth SWE Notes
11/3/2017 11/04/2017 8:00 AM 2 0.00 M M
1/26/2018 1/30/2018 8:00 AM 5 0.17 0.0 M This morning there were a few drops of rain on the deck, perhaps due to slight pptn during the night-early morning.
3/21/2018 3/22/2018 8:00 AM 2 M M M Great human error in measuring snow depth and melted snow.
4/2/2018 4/04/2018 7:30 AM 3 0.24 M M
4/4/2018 4/07/2018 8:00 AM 4 0.03 M M
4/16/2018 4/17/2018 7:30 AM 2 1.84 M M
4/30/2018 5/02/2018 7:30 AM 3 0.00 M M
6/4/2018 6/05/2018 7:30 AM 2 M M M Gauge was not available for collection.
6/13/2018 6/14/2018 7:30 AM 2 0.00 M M
6/27/2018 6/28/2018 7:30 AM 2 0.00 M M
8/2/2018 8/08/2018 7:30 AM 7 3.04 M M Very heavy rain fell yesterday about 1430. I have data from my tipping bucket LaCrosse rain gauge for 8/2, 8/3 and 8/4. The problem was fixed this AM.



Observation Date Observation Time Notes Largest Stone Size Average Stone Size Smallest Stone Size Stone Consistency Duration Minutes Durration Accuracy Damage Timing More Rain than Hail Hail Started Largest Hail Started Angle of Impact Number of Stones on Pad Distance Between Stones on Pad Depth of Stones on Ground