Dissecting a Visible Satellite Pic

Just a very brief post this morning as I'd like to show y'all the beauty of the atmosphere from above.  The satellite picture in question is from MODIS (Moderate Resolution Imaging Spectroradiometer).  I know...nerd; geek!  Relax!  It's a good tool to inspect from above terra mater.  Let's use yesterday's snowfall as the snapshot to observe...

I tried to snip from a mosaic the region around the mid-Atlantic coast which includes most of VA, WVA, NY, PA, NJ, DE, and southern New England.  I also "highlighted" 3 areas to inspect in greater detail.  Let's start with the blue arrows.  Note the linear band that runs SSW to NNE similar to I-81. This is a good shot of the nature of the banding of the precipitation in yesterday's snow.  Often, this is the case with a coastal developing storm.  The cyclonic flow brings waves of moisture off the ocean and aligns with the topography of the adjacent landmass.  Have an imagination...that line, and several others align parallel to the coast as the forced lifting from the elevated land helps in forming these bands.  If you're under one of these bands, voila, heavier snow!  Lancaster and Berks county had a solid 5-6" event as these locations remained under one of these more intensely precipitating bands for several hours as the storm moved up the coast!  Meanwhile, a mere 50-75 west of the last band, skies were filled only with high cirrus or no clouds at all as very dry air was moving in on the backside flow from O Canada. 

Now, note the red region.  Very bubbly clouds indicating good upward motion and thus good pockets of precipitation.  Bucks, Chester, Delaware, Lehigh and Montgomery counties all reported a solid 6" event yesterday.  Pockets of 1/4 mile visibility snows are clearly evident as seen from MODIS. 

Lastly, the convection and thunderstorms that evolved over the "warm" oceans!  The gulf stream runs ENE off the mid-Atlantic coast and carries vast quantities of fuel (warm water) for these storms.  A nice baroclinic (a temp, pressure, density thing!) zone (I know...nerd, geek!) steers these storms up along the coast and helps deepen the storm.  Look at the anomalous warmth of our coastal waters...

And here is a graphic depiction the observed Sea Surface Temps (SST)...that's mid-upper 60sºF water just off the Delmarva and deepening lows love that energy!  You can also clearly note the gulf stream starting with the "loop current" in the Gulf of Mexico and migrating northward along the Florida coast...

OK...enough "Sunday School"!  Enjoy the 2nd Sunday of Advent...and enjoy this Christmas ditty...

 I'm out...the gym awaits...

Smitty

AA:  Technological Device output Analysis (TDA) of a MODIS satellite pic!