Stormy Night For Some of Us

August 17, 2008

Lightning1 As always you can click on the image for a closer view, but my main reason for posting on a day off is to save the lightning image from last nights storm for posterity…or at least for the blog.  It's quite possible that you slept through the action (as I did) if you live in the middle of the city or eastside of town.  Lots of strikes from I-5 westward and down into Marion County east of I-5 too.  A heck of a warm night.  IF we don't get a massive marine push before midnight tonight, we'll probably break our all-time August low temperature record (the warm one) of 68 degrees.  We tied it yesterday.

I'm up so early because I was woken up by a strong northwest wind around 6:10am.  That early of a wake up call makes me tired, but I can catch up when it's clouds, cool, and drizzly sometime in the next 3 days.  There must have been some leftover outflow from a thunderstorm, but 22 mph seemed REAL windy with every single house/door on my house open.  I slept through the action overnight, except that first cell that formed around midnight in Clackamas county.  I saw plenty of lightning from that, but then fell asleep. 

Not wanting to get anyone too excited, but I see SPC has us (or at least the Cascades) in the SLIGHT chance for severe weather this afternoon/evening.  Here is their morning discussion:

…THERE IS A SLGT RISK OF SVR TSTMS LATER THIS AFTERNOON INTO
   TONIGHT FOR THE ORE CASCADES AREA…
  
   …WA/ORE CASCADES AREA THIS AFTERNOON INTO TONIGHT…
   A PLUME OF LOW-MID LEVEL MOISTURE HAS SPREAD NWD OVER ORE/WA…NEAR
   AND IMMEDIATELY W OF THE CASCADES…AND THIS MOISTURE HAS SUPPORTED
   A FEW THUNDERSTORMS OVERNIGHT FROM NW ORE INTO WRN WA.  THIS INITIAL
   CONVECTION WILL LIKELY WEAKEN LATER THIS MORNING…WITH ADDITIONAL
   THUNDERSTORM DEVELOPMENT EXPECTED OVER THE ORE CASCADES LATER THIS
   AFTERNOON/EVENING IN CONJUNCTION WITH DAYTIME HEATING AND THE
   APPROACH OF EMBEDDED WEAK SPEED MAXIMA IN ADVANCE OF AN ERN PAC MID
   LEVEL TROUGH.  OBSERVATIONS OF STEEP MID LEVEL LAPSE RATES ATOP
   BOUNDARY LAYER DEWPOINTS RANGING FROM THE MID 50S TO LOCALLY LOWER
   60S WILL CONTRIBUTE TO MLCAPE VALUES OF 1000-1500 J/KG BY LATER THIS
   AFTERNOON/EVENING.  THE COMBINATION OF MODERATE INSTABILITY AND
   GRADUALLY INCREASING VERTICAL SHEAR THIS AFTERNOON INTO TONIGHT
   APPEARS SUFFICIENT FOR SUPERCELLS CAPABLE OF PRODUCING LARGE HAIL
   AND DAMAGING WINDS. 


Okay, let's hope for some more this afternoon or evening!  Mark Nelsen