Station Overview Station Location
Station Number MD-AA-63 Latitude 39.1234
Station Name Severn 1.0 SSE Longitude -76.6818
County Anne Arundel Elevation (ft)



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 3.63 1.99 16 1.99 16 0.00 0 0 8 1 0.0 0 0
Nov 17 3.43 2.48 19 2.34 12 0.14 7 2 7 0 0.0 0 0
Dec 17 3.43 0.81 20 0.81 20 0.00 0 0 8 2 4.0 3 3
Jan 18 3.18 1.12 16 1.12 16 0.00 0 0 9 1 3.0 3 4
Feb 18 2.93 5.42 21 2.74 15 2.68 6 2 10 0 1.5 1 1
March 18 3.94 2.62 30 1.84 24 0.78 6 2 6 3 6.0 2 3
April 18 3.40 3.73 19 3.73 19 0.00 0 0 11 2 0.0 0 0
May 18 4.27 8.96 19 8.96 19 0.00 0 0 13 0 0.0 0 0
June 18 3.58 5.28 25 2.91 14 2.37 11 1 8 1 0.0 0 0
July 18 4.07 13.73 29 13.31 26 0.42 3 1 10 1 0.0 0 0
Aug 18 3.39 4.62 28 3.80 22 0.82 6 1 11 2 0.0 0 0
Sept 18 4.02 8.67 23 7.72 19 0.95 4 1 14 2 0.0 0 0
Water Year Totals: 43.27" 59.43" 265 days 51.27" 222 8.16" 43 days 10 115 days 15 days 14.5" 9 days 11 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 0.00
10/5/2017
10/6/2017
10/7/2017
10/8/2017
10/9/2017
10/10/2017
10/11/2017 T
10/12/2017
10/13/2017 0.06
10/14/2017 0.06
10/15/2017 0.01
10/16/2017 0.09
10/17/2017 0.01
10/18/2017 0.00
10/19/2017 0.00
10/20/2017 0.00
10/21/2017 0.00
10/22/2017 0.00
10/23/2017 0.00
10/24/2017 0.14
10/25/2017
10/26/2017
10/27/2017
10/28/2017
10/29/2017 0.32
10/30/2017 1.30
10/31/2017
11/1/2017
11/2/2017
11/3/2017
11/4/2017
11/5/2017 0.75
11/6/2017 0.01
11/7/2017 0.11
11/8/2017 1.23
11/9/2017
11/10/2017 **
11/11/2017 **
11/12/2017 **
11/13/2017 0.14
11/14/2017 0.00
11/15/2017 0.00
11/16/2017 0.01
11/17/2017
11/18/2017
11/19/2017 0.21
11/20/2017
11/21/2017
11/22/2017 0.02
11/23/2017 0.00
11/24/2017 0.00
11/25/2017 **
11/26/2017 **
11/27/2017 0.00
11/28/2017
11/29/2017
11/30/2017 0.00
12/1/2017 0.01
12/2/2017
12/3/2017 0.02
12/4/2017
12/5/2017
12/6/2017 0.12
12/7/2017 0.00
12/8/2017
12/9/2017 0.00
12/10/2017 0.29
12/11/2017
12/12/2017 0.00
12/13/2017
12/14/2017
12/15/2017
12/16/2017 0.08
12/17/2017 0.00
12/18/2017 T
12/19/2017 0.00
12/20/2017 0.00
12/21/2017 0.00
12/22/2017 0.00
12/23/2017 0.03
12/24/2017 0.21
12/25/2017 T
12/26/2017 0.00
12/27/2017 0.00
12/28/2017
12/29/2017
12/30/2017 0.05
12/31/2017
Day of YearDaily PrcpMultiday Prcp
1/1/2018
1/2/2018
1/3/2018
1/4/2018 0.11
1/5/2018 0.01
1/6/2018
1/7/2018
1/8/2018
1/9/2018
1/10/2018
1/11/2018
1/12/2018 0.15
1/13/2018 0.50
1/14/2018 0.00
1/15/2018 0.00
1/16/2018
1/17/2018 0.10
1/18/2018 T
1/19/2018
1/20/2018
1/21/2018
1/22/2018
1/23/2018 0.09
1/24/2018 0.00
1/25/2018 0.00
1/26/2018 0.00
1/27/2018
1/28/2018 0.05
1/29/2018 0.10
1/30/2018 0.01
1/31/2018 0.00
2/1/2018
2/2/2018 0.06
2/3/2018
2/4/2018
2/5/2018 1.22
2/6/2018 0.00
2/7/2018 0.01
2/8/2018 0.33
2/9/2018 0.00
2/10/2018 **
2/11/2018 **
2/12/2018 2.23
2/13/2018 0.05
2/14/2018 0.00
2/15/2018 0.02
2/16/2018 0.10
2/17/2018 0.05
2/18/2018 0.68
2/19/2018
2/20/2018
2/21/2018
2/22/2018 0.00
2/23/2018 0.22
2/24/2018 **
2/25/2018 **
2/26/2018 0.45
2/27/2018 0.00
2/28/2018
3/1/2018 0.00
3/2/2018 **
3/3/2018 **
3/4/2018 **
3/5/2018 0.23
3/6/2018 0.00
3/7/2018 **
3/8/2018 0.55
3/9/2018 0.00
3/10/2018 0.00
3/11/2018 0.00
3/12/2018 0.00
3/13/2018 0.04
3/14/2018 0.00
3/15/2018 0.00
3/16/2018 0.00
3/17/2018 T
3/18/2018 0.00
3/19/2018 0.00
3/20/2018 T
3/21/2018 0.87
3/22/2018 0.81
3/23/2018 0.00
3/24/2018 0.00
3/25/2018 0.00
3/26/2018 T
3/27/2018
3/28/2018 0.02
3/29/2018 0.07
3/30/2018 0.00
3/31/2018 0.03
Day of YearDaily PrcpMultiday Prcp
4/1/2018 0.00
4/2/2018 0.10
4/3/2018 0.01
4/4/2018 0.01
4/5/2018 0.03
4/6/2018 0.00
4/7/2018 0.00
4/8/2018 0.00
4/9/2018 0.00
4/10/2018
4/11/2018
4/12/2018
4/13/2018
4/14/2018
4/15/2018 T
4/16/2018 1.70
4/17/2018 0.07
4/18/2018
4/19/2018
4/20/2018 T
4/21/2018 0.00
4/22/2018
4/23/2018
4/24/2018
4/25/2018 1.09
4/26/2018 0.02
4/27/2018 0.55
4/28/2018 0.12
4/29/2018 0.03
4/30/2018
5/1/2018
5/2/2018
5/3/2018
5/4/2018
5/5/2018
5/6/2018
5/7/2018
5/8/2018
5/9/2018 0.00
5/10/2018
5/11/2018
5/12/2018
5/13/2018 0.35
5/14/2018 0.41
5/15/2018 0.22
5/16/2018 2.61
5/17/2018 1.65
5/18/2018 1.32
5/19/2018 1.13
5/20/2018 0.13
5/21/2018 0.00
5/22/2018 0.00
5/23/2018 0.43
5/24/2018 0.00
5/25/2018 0.00
5/26/2018 0.00
5/27/2018 0.02
5/28/2018 0.67
5/29/2018 0.01
5/30/2018 0.01
5/31/2018
6/1/2018 0.86
6/2/2018 **
6/3/2018 **
6/4/2018 2.37
6/5/2018 0.00
6/6/2018 0.03
6/7/2018 0.00
6/8/2018 0.00
6/9/2018 0.00
6/10/2018 0.48
6/11/2018 1.42
6/12/2018 0.06
6/13/2018
6/14/2018
6/15/2018 0.00
6/16/2018
6/17/2018
6/18/2018
6/19/2018 T
6/20/2018 0.03
6/21/2018 0.01
6/22/2018 0.02
6/23/2018 **
6/24/2018 **
6/25/2018 **
6/26/2018 **
6/27/2018 **
6/28/2018 **
6/29/2018 **
6/30/2018 **
Day of YearDaily PrcpMultiday Prcp
7/1/2018 **
7/2/2018 **
7/3/2018 0.42
7/4/2018 0.00
7/5/2018 0.00
7/6/2018 0.00
7/7/2018 0.00
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 0.01
7/17/2018 0.90
7/18/2018 0.97
7/19/2018 0.00
7/20/2018 0.00
7/21/2018 T
7/22/2018 5.30
7/23/2018 1.11
7/24/2018 0.86
7/25/2018 2.78
7/26/2018 0.41
7/27/2018 0.00
7/28/2018 0.78
7/29/2018
7/30/2018
7/31/2018 0.19
8/1/2018 0.26
8/2/2018 0.26
8/3/2018 0.42
8/4/2018 0.83
8/5/2018
8/6/2018 0.67
8/7/2018 0.18
8/8/2018 0.20
8/9/2018 0.00
8/10/2018 0.00
8/11/2018 0.00
8/12/2018 T
8/13/2018 0.23
8/14/2018 0.60
8/15/2018
8/16/2018 0.00
8/17/2018 0.00
8/18/2018 0.05
8/19/2018 T
8/20/2018 **
8/21/2018 **
8/22/2018 **
8/23/2018 **
8/24/2018 **
8/25/2018 0.82
8/26/2018 0.00
8/27/2018 0.00
8/28/2018 0.00
8/29/2018 0.00
8/30/2018
8/31/2018 0.10
9/1/2018 **
9/2/2018 **
9/3/2018 **
9/4/2018 0.95
9/5/2018
9/6/2018
9/7/2018 T
9/8/2018 0.51
9/9/2018 1.76
9/10/2018 1.28
9/11/2018 0.03
9/12/2018 0.08
9/13/2018 0.06
9/14/2018
9/15/2018 0.03
9/16/2018 T
9/17/2018 0.00
9/18/2018 0.94
9/19/2018
9/20/2018 0.00
9/21/2018 0.00
9/22/2018 0.06
9/23/2018 0.46
9/24/2018 0.84
9/25/2018 0.46
9/26/2018 0.12
9/27/2018 1.09
9/28/2018
9/29/2018
9/30/2018



Observation Date Observation Time Precipitation Snowfall Snowfall SWE Snow Depth Snow SWE Notes
10/4/2017 7:00 AM 0.00 M M M M
10/11/2017 7:00 AM T M M M M Light precip early this morning
10/13/2017 7:00 AM 0.06 M M M M
10/14/2017 8:00 AM 0.06 M M M M Cloudy with light drizzle for most of the day.
10/15/2017 8:00 AM 0.01 M M M M
10/16/2017 7:00 AM 0.09 M M M M Light drizzle and light rain associated with passage of front. Rain began around midnight.
10/17/2017 7:00 AM 0.01 M M M M
10/18/2017 7:00 AM 0.00 M M M M
10/19/2017 7:00 AM 0.00 M M M M
10/20/2017 7:00 AM 0.00 M M M M
10/21/2017 7:00 AM 0.00 M M M M
10/22/2017 7:00 AM 0.00 M M M M
10/23/2017 7:00 AM 0.00 M M M M
10/24/2017 7:00 AM 0.14 M M M M Rain associated with cold front overnight. Trmps still warm in low 70s overnight
10/29/2017 8:30 AM 0.32 M M M M Rain starting overnight continuingg this morning
10/30/2017 6:45 AM 1.30 M M M M Rain all day yesterday with only short breaks. Rain heavy at times. Tropical moisture wrung out along frontal boundary. Becoming very windy overnight into the morning.
11/5/2017 8:00 AM 0.75 M M M M Light to moderste rain from yesterday evening continuing through this morning.
11/6/2017 7:00 AM 0.01 M M M M Additional misty rains
11/7/2017 6:30 AM 0.11 M M M M Rain during the late afternoon/evening yesterday. Turning significantly colder w/ frontal passage. High temps going from low 70s to mid 40s today
11/8/2017 6:30 AM 1.23 M M M M Mod to locally heavy rains much of the day yesterday tapering off to light drizzle by late evening that continued overnight. Wet and cold
11/14/2017 7:00 AM 0.00 M M M M
11/15/2017 7:00 AM 0.00 M M M M
11/16/2017 7:00 AM 0.01 M M M M Overnight shower
11/19/2017 7:00 AM 0.21 M M M M Rainy and extremely windy Sat nightwith frontal passage
11/22/2017 7:00 AM 0.02 M M M M Rain showers overnight
11/23/2017 7:00 AM 0.00 M M M M Happy Thanksgiving Day!
11/24/2017 7:00 AM 0.00 M M M M
11/30/2017 7:00 AM 0.00 M M M M
12/1/2017 7:00 AM 0.01 M M M M Light rain around 10pm last night. Overnight lows in low 40s
12/3/2017 8:00 AM 0.02 M M M M Overnight rain
12/6/2017 7:00 AM 0.12 M M M M Rain overnight Tuesday with frontal boundary. Highs Tues in low 60s but cloudy. Temps cooling off quickly by Wed morning
12/7/2017 7:00 AM 0.00 M M M M
12/9/2017 7:00 AM 0.00 M M M M No precip overnight. First snow of the season likely to start falling this morning.
12/10/2017 7:00 AM 0.29 3.2 M 3.0 M Snow fell yesterday from about 9am - 6pm
12/12/2017 7:00 AM 0.00 0.0 M T M Most of the snow in the yard is melted. Goodbye first snow of the season. Only a few isolated patched left.
12/16/2017 8:00 AM 0.08 0.5 M 0.5 M Sleet starting around noon continuing on and off into early afternoon. Changeover to snow/sleet and eventually all snow. Continued light snow through early evening.
12/17/2017 7:00 AM 0.00 0.0 M T M Remnants of yesterdays snow lingering in a few spots but mostly melted
12/18/2017 7:00 AM T 0.0 M 0.0 M Light rain showers overnight
12/19/2017 7:00 AM 0.00 0.0 M 0.0 M Mild overnight. Temps near 60F expected today before front comes through.
12/20/2017 7:00 AM 0.00 0.0 M 0.0 M
12/21/2017 7:00 AM 0.00 0.0 M 0.0 M
12/22/2017 7:00 AM 0.00 0.0 M 0.0 M
12/23/2017 7:00 AM 0.03 0.0 M 0.0 M Light rain overnight
12/24/2017 7:00 AM 0.21 0.0 M 0.0 M Several rounds of rain. Temps yesterday in low 60s
12/25/2017 7:00 AM T 0.0 M 0.0 M Light drizzle on Christmas Eve
12/26/2017 7:00 AM 0.00 M M M M
12/27/2017 7:00 AM 0.00 0.0 M 0.0 M
12/30/2017 8:30 AM 0.05 0.3 M 0.3 M Light snow fell overnight. Start time unknown but ended before 8:30am. Snow was very lightweight and powdery.
1/4/2018 6:30 AM 0.11 1.8 0.11 1.8 0.11 Snow from East Coast storm started falling just after 11pm last night. 0.2” accumulated by 1 am. Moderate snow falling this morning before 6am but snow has now nearly come to a stop. Winds starting to increase this morning.
1/5/2018 7:00 AM 0.01 0.1 M 1.0 0.10 Extremely windy and cold all day yesterday. Another 0.1” snowfall accumulation after previous ob. Storm total 1.9”
1/12/2018 7:00 AM 0.15 0.0 M 0.0 M All snow melted after yesterdays high temp reached 62F. Still raining st time of ob. Current temp 59F with overnight low of 54F.
1/13/2018 8:00 AM 0.50 0.0 M 0.0 M Rain for portions of the day yeaterday. Mostly in early morning and evening hours with some precip still falling after midnight. Temps still warm at 58F as of 2am but winds became quite strong after midnight with approaching frontal boundary. Temps down to 32F by 8am this morning.
1/14/2018 8:00 AM 0.00 0.0 M 0.0 M
1/15/2018 8:00 AM 0.00 0.0 M 0.0 M
1/17/2018 8:00 AM 0.10 1.1 M 1.1 M Still snowing lightly at time of ob.
1/18/2018 8:00 AM T T M 0.8 M Light snow continuing after 8am yesterday. Finished by ~8:30-8:45. Minimal additional accumulation
1/23/2018 8:00 AM 0.09 0.0 M 0.0 M Rain showers overnight. One very heavy downpour (tstorm related) around 7am this morning. Temps still very warm this morning in upper 50s but going to fall off after today.
1/24/2018 8:00 AM 0.00 0.0 M 0.0 M
1/25/2018 7:00 AM 0.00 0.0 M 0.0 M
1/26/2018 7:00 AM 0.00 0.0 M 0.0 M
1/28/2018 9:00 AM 0.05 0.0 M 0.0 M Warm and rainy this morning. Temp currently 50F. Still raining lightly at time of observation.
1/29/2018 7:00 AM 0.10 0.0 M 0.0 M Drizzle throughout most of the day into evening Sunday. Temps mild in low 50s
1/30/2018 8:00 AM 0.01 0.0 M 0.0 M Light rain early this morning. Temps a few degrees above freezing and likely to fall today.
1/31/2018 7:00 AM 0.00 0.0 M 0.0 M
2/2/2018 7:00 AM 0.06 0.0 M 0.0 M Rain overnight. Becoming very windy
2/5/2018 8:00 AM 1.22 T M 0.0 M Snow starting around 9:30am changing over to sleet and freezing rain by 11. Then continued freezing rain and rain into the evening. Only a thin accumulation of ice except for on trees where at least 0.10” accumulated.
2/6/2018 7:00 AM 0.00 M M M M
2/7/2018 8:00 AM 0.01 T M T M Light glaze of freezing rain on most surfaces. Cars and deck held the ice the best while blacktop/sidewalks weren’t too bad.
2/8/2018 7:00 AM 0.33 0.0 M 0.0 M Cold rain during late morning into afternoon yesterday. Becoming windy overnight with frontal passage.
2/9/2018 7:00 AM 0.00 M M M M
2/13/2018 7:00 AM 0.05 0.0 M 0.0 M Storm total of 2.28”
2/14/2018 7:00 AM 0.00 0.0 M 0.0 M
2/15/2018 7:00 AM 0.02 0.0 M 0.0 M Overnight rain showers
2/16/2018 7:00 AM 0.10 0.0 M 0.0 M Unseasonably warm temperatures yesterday reaching 70F as the sun broke out late in the afternoon to enhance stronn WAA. Brief sprinkles yesterday afternoon followed by overnight rain continuing this morning.
2/17/2018 7:00 AM 0.05 0.0 M 0.0 M Rain from passage of frontal boundary. Temps dropping through the day
2/18/2018 8:00 AM 0.68 1.5 M 1.0 M Snow/sleet mix started around 2pm becoming all snow a short time later. Snow became moderately heavy but didnt start accumulating on roads/sidewalks until after 4:30pm. About 1.5” snow accumulation followed by changing to sleet and freezing rain/rain.
2/22/2018 7:00 AM 0.00 0.0 M 0.0 M
2/23/2018 7:00 AM 0.22 0.0 M 0.0 M Rain overnight and this morning
2/27/2018 7:00 AM 0.00 0.0 M 0.0 M
3/1/2018 7:00 AM 0.00 0.0 M 0.0 M Significant wind event starting overnight tonight
3/6/2018 7:00 AM 0.00 0.0 M 0.0 M
3/9/2018 7:00 AM 0.00 M M 0.0 M
3/10/2018 7:00 AM 0.00 0.0 M 0.0 M
3/11/2018 7:00 AM 0.00 0.0 M 0.0 M
3/12/2018 7:00 AM 0.00 0.0 M 0.0 M
3/13/2018 7:00 AM 0.04 T M T M Lisght snow fell between 9-11pm last night mixing with sleet/freezing rain towards the end of the event. Ground too warm in most spots for accumulation. Light glaze of snow/ice on cars and mulchbeds.
3/14/2018 7:00 AM 0.00 0.0 M 0.0 M Chilly
3/15/2018 7:00 AM 0.00 0.0 M 0.0 M Chilly
3/16/2018 7:00 AM 0.00 0.0 M 0.0 M
3/17/2018 7:00 AM T T M 0.0 M Snow showers yesterday morning. No accumulation.
3/18/2018 7:00 AM 0.00 0.0 M 0.0 M
3/19/2018 7:00 AM 0.00 0.0 M 0.0 M
3/20/2018 7:00 AM T T M 0.0 M Rain snd sleet mix started falling just before 7am this morning.
3/21/2018 8:00 AM 0.87 0.5 M 0.3 M Cold rain on the morning of the 20th starting just before 7am. Some sleet was mixed with the rain around 7am as I was leaving for work. Heavy rain was falling around 8-8:30am. Throughout the day, rain and mixed wintry precip fell going over to all freezing rain and then all sleet in the mid-late afternoon. Then changed to all snow around 5pm lasting through 7-8pm. Very little precip appears to have fallen overnight. Roads are just wet. Light freezing rain just before 8am has just changed over to snow again.
3/22/2018 7:00 AM 0.81 5.5 0.79 4.0 M Late March snowstorm! Approximately 0.25" of ice/sleet was already on the ground from the first part of the storm on the previous day. Very light freezing drizzle changed over to snow at 8am, which became heavy in a short time. 1"/hr snowfall rates from ~8am-noon. Snow continued to fall through the afternoon gradually become lighter but accumulation was much diminished due to the stronger sun angle. Snow ended around 4:00pm with only a few short periods of snow showers that persisted through the evening.
3/23/2018 7:00 AM 0.00 0.0 M 1.0 M Significant amount of snowmelt yesterday. Large parts of the yard now bare.
3/24/2018 7:00 AM 0.00 0.0 M T M Snow only left in the shadowy portions of the yard.
3/25/2018 7:00 AM 0.00 0.0 M 0.0 M Snow cover gone. Only piles remain.
3/26/2018 7:00 AM T T M 0.0 M Very brief (less than 2 min) period of snow showers yesterday around 1:15pm. No accumulation.
3/28/2018 6:45 AM 0.02 0.0 M 0.0 M Light rain yesterday and overnight
3/29/2018 7:00 AM 0.07 0.0 M 0.0 M Light rain yesterday throughout the day
3/30/2018 7:00 AM 0.00 0.0 M 0.0 M Very warm and mostly sunny on Thursday 3/29. High temp of 72F observed around midnight with approach of front. Near 70F during late afternoon.
3/31/2018 7:00 AM 0.03 M M M M
4/1/2018 7:00 AM 0.00 M M M M
4/2/2018 7:00 AM 0.10 0.0 M 0.0 M Light rain overnight. Drizzling at time of ob.
4/3/2018 7:00 AM 0.01 0.0 M 0.0 M
4/4/2018 7:00 AM 0.01 0.0 M 0.0 M
4/5/2018 7:00 AM 0.03 0.0 M 0.0 M Strong cold front moved through the region in the midday hours with some light precip. Winds became very strong following fropa with weather station reporting (sheltered) gust to 34mph. Winds continued into the night. Some shingles lost on neighbors roofs (mostly those who face W).
4/6/2018 7:00 AM 0.00 0.0 M 0.0 M
4/7/2018 8:00 AM 0.00 0.0 M 0.0 M So muh for snow. ??
4/8/2018 8:00 AM 0.00 0.0 M 0.0 M Significantly colder on Sat than Fri (highs in mid 40s vs upper 60s)
4/9/2018 7:00 AM 0.00 0.0 M 0.0 M
4/15/2018 8:00 AM T 0.0 M M 0.00 Very light drizzle falling
4/16/2018 7:00 AM 1.70 0.0 M 0.0 M Light to moderate rain for most of the day Sunday (yesterday) as well as unseasonably cool temperatures. Very heavy rain fell overnight. Weather station indicated maximum rainrate of 8.35 in/hr occurred around 3:15am. Temps rose to near 60F by this morning as warm front surged north.
4/17/2018 7:00 AM 0.07 0.0 M 0.0 M Additional rain Monday morning
4/20/2018 7:00 AM T 0.0 M 0.0 M Cloufy eith light drizzle in morning
4/21/2018 7:00 AM 0.00 0.0 M 0.0 M
4/25/2018 7:00 AM 1.09 0.0 M 0.0 M Light rain starting yesterday late afternoon becoming moderate by late evening. Heavy rains moved in around midnight. Mostly done by this morning but some light showers were lingering across the area.
4/26/2018 7:00 AM 0.02 0.0 M 0.0 M Additional rain falling after 7am Wednesday morning. Over 1” of rain (prior to 7am) caused minor street ponding.
4/27/2018 7:00 AM 0.55 0.0 M 0.0 M Rain overnight and continuing at time of ovservation.
4/28/2018 7:00 AM 0.12 0.0 M 0.0 M Additional precip Friday morning after 7am.
4/29/2018 8:00 AM 0.03 0.0 M 0.0 M Drizzle and light rain with passage of frontal boundary. Warm temps Sat with highs around 75F. Windy and cooler after fropa. Temps near 40F this morning.
5/9/2018 7:00 AM 0.00 M M M M
5/13/2018 7:00 AM 0.35 M M M M FROPA with strong winds, very dark skies, and briefly intense rain (5”/hr rainrates). Nice day up until 7:30pm when the storms rolled through.
5/14/2018 7:00 AM 0.41 M M M M Rain during the morning for Mothers Day followed by light drizzle. Then thunderstorms overnight
5/15/2018 7:00 AM 0.22 M M M M Strong bowing MCS moved through the aDc Region ~6-8pm. Very dark skies, lots of lightning/thunder, and briefly heavy rain.
5/16/2018 7:00 AM 2.61 M M M M Thunderstorms moved through the region during late evening/early nighttime hours. Significant lightning and intense rain rates lasting for ~2-3 hours. Max rainrates >10”/hr
5/17/2018 7:00 AM 1.65 M M M M Rain showers during the day yesterday becoming a steady rain late in the afternoon/evening. Rain continued overnight with light drizzle still falling this morning.
5/18/2018 7:00 AM 1.32 M M M M Briefly heavy rain fell yesterday morningn but was then light throughout most of the rest of the day. Short break in the rain around 5pm before picking back up evening/overnight. 3rd consecutive day with greater than 1” of rainfall.
5/19/2018 8:00 AM 1.13 M M M M 4th consecutive day of >1” of rainfall. Rain for most of the day yesterday with 0.50” accumulated by 6pm
5/20/2018 8:00 PM 0.13 M M M M Light continued Saturday as the storm system finally began to depart the region. Rain mostly in morning but some showers lingered into the afternoon as well.
5/21/2018 7:00 AM 0.00 M M M M No rain on Sunday. Hot with temps near 90F.
5/22/2018 7:00 AM 0.00 M M M M Dry with max temps in 70s and low humidity.
5/23/2018 7:00 AM 0.43 M M M M Rain showers throughout the day. Then heavy rain as a strong line of storms moved through the region.
5/24/2018 7:00 AM 0.00 M M M M Ground still plenty moist from last weeks and Tuesdays rain.
5/25/2018 8:00 AM 0.00 M M M M
5/26/2018 8:00 AM 0.00 M M M M
5/27/2018 8:00 AM 0.02 M M M M Rain showers yesterday afternoon
5/28/2018 8:00 AM 0.67 M M M M Very heavy rain for a brief period from tstorms. Cells were training to the north and northwest but had trouble pushing southward. Ellicott city had severe flooding similar to July 2016.
5/29/2018 7:00 AM 0.01 M M M M Light drizzle yesterday late morning and into midday
5/30/2018 7:00 AM 0.01 M M M M
6/1/2018 7:00 AM 0.86 M M M M Strong line of thunderstorms with heavy rainfall/intense lightning (mostly cloud-cloud and intracloud). Shelf cloud and mammatus observed.
6/5/2018 7:00 AM 0.00 M M M M
6/6/2018 7:00 AM 0.03 M M M M Light rain from storms that passed by to the north around 9pm.
6/7/2018 7:00 AM 0.00 M M M M
6/8/2018 7:00 AM 0.00 M M M M
6/9/2018 7:00 AM 0.00 M M M M
6/10/2018 8:00 AM 0.48 M M M M Intense rainfall and CG lightning from tstorm that moved south through the area and rapidly developed over BWI. Extremely loud thunder for ~30 minutes.
6/11/2018 7:00 AM 1.42 M M M M Heavy rain from tstorms moving southeast through central MD followed by continuing light/moderate rains.
6/12/2018 6:45 AM 0.06 M M M M
6/15/2018 7:00 AM 0.00 M M M M
6/19/2018 7:00 AM T M M M M
6/20/2018 7:00 AM 0.03 M M M M
6/21/2018 7:00 AM 0.01 M M M M
6/22/2018 7:00 AM 0.02 M M M M
7/4/2018 7:00 AM 0.00 M M M M Stilll very hot. Temps near 100F on multiple days to start July and no precip. Very muggy and dry as well with unwatered grass quickly turning brown.
7/5/2018 7:00 AM 0.00 M M M M Slightly less hot conditions for July 4th though still muggy. No rain
7/6/2018 7:00 AM 0.00 M M M M
7/7/2018 7:00 AM 0.00 M M M M
7/8/2018 7:00 AM 0.00 M M M M
7/9/2018 7:00 AM 0.00 M M M M
7/10/2018 7:00 AM 0.00 M M M M
7/11/2018 7:00 AM 0.00 M M M M
7/12/2018 7:00 AM 0.00 M M M M
7/13/2018 7:00 AM 0.00 M M M M
7/14/2018 7:00 AM 0.00 M M M M
7/15/2018 7:00 AM 0.00 M M M M
7/16/2018 7:00 AM 0.01 M M M M Passing thunderstorms clipped the area as they passed by to the north. About 5min of moderate rain
7/17/2018 7:00 AM 0.90 M M M M Very heavy rains, strong winds, severe CG lightning, and loud thunder between ~545-6:15pm. Rain rates up to 5”/hr at times.
7/18/2018 7:00 AM 0.97 M M M M Heavy rains from thunderstorms the previous evening with fropa. Humidity and temps expected to be about 8-10F cooler afterwards.
7/19/2018 7:00 AM 0.00 M M M M
7/20/2018 7:00 AM 0.00 M M M M
7/21/2018 7:00 AM T M M M M Light shower last night around 10pm and additional sprinkles this morning.
7/22/2018 7:30 AM 5.30 M M M M Continuous rain started just after 8am yesterday morning and fell nonstop through about midnight-1am. Rainfall was very heavy (but non-tstrm) for the most part from the late morning into the early evening and picking up in intensity again around 10pm. Breezy conditions during the afternoon caused driving rain. Some trees came down due to very wet soil conditions.
7/23/2018 7:00 AM 1.11 M M M M Day started off sunny but quickly clouded up. Periods of rain during the afternoon (sometimes briefly very heavy). Three rounds of tstorms moving from south to north through central MD during the afternoon and evening hours. Flooding exacerbated by the very wet antecedent conditions caused by previous days' rain.
7/24/2018 7:00 AM 0.86 M M M M Showers and tstorms yesterday, overnight, and this morning
7/25/2018 7:00 AM 2.78 M M M M Another day of a lot of rain. Heaviest rains fell after midnight and through the overnight hours.
7/26/2018 7:00 AM 0.41 M M M M Strongn tstorms moved through the region between 6-10pm. Briefly heavy rains would come and go during this period.
7/27/2018 7:00 AM 0.00 M M M M Finally a day with no rain!
7/28/2018 8:00 AM 0.78 M M M M Strong tstorms yesterday afternoon and evening.
7/31/2018 7:00 AM 0.19 M M M M Rain in early evening (~5:30pm - 8pm)
8/1/2018 7:00 AM 0.26 M M M M Rain overnight
8/2/2018 7:00 AM 0.26 M M M M Overnight tstorms thst mo ed through between 10pm-midnight.
8/3/2018 7:00 AM 0.42 M M M M Multiple rounds of mod to heavy rains
8/4/2018 7:00 AM 0.83 M M M M
8/6/2018 7:00 AM 0.67 M M M M Strong thunderstorm moved through from SW to NE during the evening.
8/7/2018 6:30 AM 0.18 M M M M Pop up scattered afternoon tstorms
8/8/2018 7:00 AM 0.20 M M M M Previous afternoon tstorms
8/9/2018 7:00 AM 0.00 M M M M Finally a 24 hr period without rain!
8/10/2018 7:00 AM 0.00 M M M M
8/11/2018 7:00 AM 0.00 M M M M
8/12/2018 7:00 AM T M M M M
8/13/2018 7:00 AM 0.23 M M M M Tstorms moved through late Sun afternoon
8/14/2018 7:00 AM 0.60 M M M M Very heavy rain for a large early evening tstorm the moved from sw-ne
8/16/2018 8:00 AM 0.00 M M M M
8/17/2018 8:00 AM 0.00 M M M M
8/18/2018 8:00 AM 0.05 M M M M Rain from passing showers/tstorms in the evening
8/19/2018 8:00 AM T M M M M Brief sprinkles during afternoon
8/26/2018 7:00 AM 0.00 0.0 M M M
8/27/2018 7:00 AM 0.00 0.0 M M M
8/28/2018 7:00 AM 0.00 0.0 M M M
8/29/2018 7:00 AM 0.00 0.0 M M M
8/31/2018 7:00 AM 0.10 M M M M Overnight shower
9/7/2018 7:00 AM T M M M M
9/8/2018 8:30 AM 0.51 M M M M Tstorms previous evening and rain overnight
9/9/2018 8:30 AM 1.76 M M M M Rain all afternoon and into the evening. Additional rain during early morning and morning hours.
9/10/2018 7:00 AM 1.28 M M M M Rain fell for much of the day yesterday with wet and windy conditions
9/11/2018 7:00 AM 0.03 M M M M Periods of light rain yesterday and early this morning
9/12/2018 6:30 AM 0.08 M M M M Spotty showers modtly during evening
9/13/2018 7:00 AM 0.06 M M M M Rain in afternoon and evening.
9/15/2018 7:00 AM 0.03 M M M M
9/16/2018 7:00 AM T M M M M Brief light drizzle yesterday morning
9/17/2018 7:00 AM 0.00 M M M M
9/18/2018 6:30 AM 0.94 M M M M Rainfall associated with the remnants of Hurricane Florence. 0.25” of rain fell from afternoon/early evening showers & tstorms. The rest came overnight as a set of 3 intense supercells moved through the area. FFW issued by local NWS at 2 am citing 2-4” possible. Intense thunder and lightning for the time of night to go along with very heavy rains.
9/20/2018 7:00 AM 0.00 M M M M
9/21/2018 7:00 AM 0.00 M M M M
9/22/2018 7:00 AM 0.06 M M M M Rain from showers that moved through early Sat morning.
9/23/2018 11:00 AM 0.46 M M M M Rain beginning early this morning before dawn. Rain has been heavy at times Sun morning.
9/24/2018 7:00 AM 0.84 M M M M Rain/drizzle for majority of the day yesterday. Still lightly drizzling this morning.
9/25/2018 7:00 AM 0.46 M M M M Rain for a good deal of the previous day
9/26/2018 7:00 AM 0.12 M M M M Light rain on and off yesterday.
9/27/2018 7:00 AM 1.09 M M M M Warm sunny day (highs near 90F) but strong line of tstorms moved through the region around 6-8pm. Intense rain rates for ~30 minutes



Start Date End Date & Time Duration in Days Precipitation Snow Depth Snow Depth SWE Notes
11/10/2017 11/13/2017 7:00 AM 4 0.14 M M
11/25/2017 11/27/2017 7:00 AM 3 0.00 M M
2/10/2018 2/12/2018 7:00 AM 3 2.23 0.0 0.00
2/24/2018 2/26/2018 7:00 AM 3 0.45 0.0 M
3/2/2018 3/05/2018 7:00 AM 4 0.23 0.0 M Rain and major wind event while we were away in Salem. Wind gusts to 60-70mph in the DC region. Rainfall may have evaporated some before I was able to check it on Sunday.
3/7/2018 3/08/2018 7:00 AM 2 0.55 1.1 M
6/2/2018 6/04/2018 7:00 AM 3 2.37 M M
6/23/2018 7/03/2018 7:00 AM 11 0.42 M M
8/20/2018 8/25/2018 7:00 AM 6 0.82 M M Rains during the week that I was on travel to Kansas City, MO.
9/1/2018 9/04/2018 7:00 AM 4 0.95 M M Rain over Labor Day weekend. Strong tstorms were in the area Friday night and showers/storms on Sat/Sun. Brief downpour on Monday afternoon (Labor Day) as well.



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