Mariton: Storm Stats

March 17, 2017

by Tim Burris, Preserve Manager

Our most recent nor’easter (March 14 & 15) was interesting. Nor’easters are high energy lows that often tap into coastal moisture (and warmth) before merging with a colder northern low.  Like all low pressure systems they rotate counterclockwise, so the winds start off in a north easterly direction.  A nor’easter packs strong winds.  If located off shore, those winds can lead to coastal flooding as water is continually pushed on shore with no escape.  Because of the high winds and drifting, it can be difficult to estimate snow depths.  The snow can be wet or dry depending on how much warmth the system picks up while forming in the south.

I generally don’t measure snow fall depths. While it is interesting, there is so much variability that I put more faith in my rain gauge after the precipitation is melted.  On Tuesday, I was about to start plowing around 11 a.m. as I didn’t see it snowing outside the window.  When I opened to the office door I discovered a down pour of soft sleet.  It was more like rain than sleet.  It didn’t fall as crystals, but it didn’t fall as drops either.  “It must have been sleet though, because the radar and weather forecasters all said there was absolutely no rain in the area.”  Anyways this heavy precipitation fell for about an hour.  Trust me, this type of precipitation affected snow depths.

The storm was interesting from a rain gauge standpoint. From the two day storm, I recorded 2.03 inches of melted precipitation.   Two inches is A LOT of water in a day and a half.  This however came as mixed precipitation.  To put it into perspective, with colder temperatures in the upper atmosphere this could easily have yielded 20 inches of snow.  Had this been a January storm with shorter days and extremely cold temperatures, we could have seen 30 inches or more of snow.  Yet, when I ran the snow blower through the grass for a snow depth indicator I couldn’t find more than 9 – 10 inches of snow.  That is why my rain gauge tells me more than a yardstick.

If you thought it was heavy to shovel you are right.  Two inches of water on a 18″ x 12″snow shovel weighs over 15 pounds.  You can do the math on how many shovelfuls you lifted.