Wild Friday

What a day of weather we experienced on Friday, the day of the winter solstice for 2018!  From this point forward on the calendar, the sun will slowly climb in the sky until the June 2019 solstice.  The days will slowly lengthen as winter's chill strengthens! (But that is a different story for a different day...). As for our ONE mere degree short of tying a 95 year old record for a max temperature, (63ºF was the high), we experienced warmth, high dew point air, heavy rains, and even a relatively rare December thunderstorm or two!  The official climate summary includes all of these plus...fog.  After a gusty and drying Saturday, things will calm down for Christmas week until another major cyclone develops over the middle part of the continent.  That storm will be a pattern changer to bring the colder temps back towards the eastern half of North America.  Onto the graphics...

First, the 1"+ of rain has the streams maxed out...again...most streams in PA running greater than their history for this time of year...

And my local stream...

And Greg...it appears that Penns Creek would be blown out at this time; its rockin' through the Poe Valley!  Coburn to Glen Iron would be a fast run!

Yes...it's been quite wet!  Take a look...first, month to date...

And now year to date...wow!  The graphic below is the percent of precip compared to norms.  Some places in southern PA have doubled their normal annual precip!  For us in our region, we are looking officially at +25" for the year (KMDT's 30 year mean is ~40" per year and we are quickly approaching 65"!)

Here's what our wettest year (2011) looked like thanks to Irene and Lee and numerous springtime  thunderstorms and in spite of a rather dry winter...

This week looks to be rather seasonal and reasonable for late December...high pressure seems to want to take control of most of the continent building from central and western O Canada to the east coast.  A tad of unsettled wx in the desert SW and note the Friday storm still spinning in the maritimes. Christmas day.  This shows the blocking that exists and could spell issues later in the winter for us.  When the cold invades, it will tend to hold for longer periods of time. 

The North Atlantic Oscillation is heading negative and that hints at cold and snowier times lie ahead.  Note that back in earlier December it too telegraphed the cold that was in place for late November and early to mid December.  It wasn't until recently that North America was flooded with Pacific origin air but that is about to change once again...I will only display the NAO graphic, the other ocean teleconnections are aligning for what could end up being a nasty January...just sayin'...

This is what a negative NAO creates in terms of temps across the US.  The graphic below is from work done by MAD US Weather by analoging years that experienced a -NAO.  Brrrrr...

OK...I've dug into the weeds plenty for y'all.  I don't want to lose you, my loyal readers.  I do greatly appreciate those of you who read these posts regularly...and to all of you, a very Merry (I do believe Green) Christmas.  The Euro keeps the dome over the KMDT area preventing any snow here...oh well.

I will leave y'all with this Christmas song...my favorite rendition especially with Sarah Mc...I hope you enjoy as much as I...

Smitty

AA:  What a warm and wild Friday!  Now back to typical December weather.  January does look to me to be hinting at a return to some nasty winter time weather.  Merry Christmas my friend.