Hold On Storms

Monday December 5

— YELLOW ALERT for WIND this weekend — 

Stormy December wx may be coming.  For this forecast, we’ll focus on 4 storms. Refill your morn’n Mug. 

A drab pattern is on tap for the first 3 days of this week.  Plenty of foggy bottoms and calm conditions.  Take advantage, if there is outdoor work to do, as we may be entering a classic stormy December period.  Admittedly, we have forecast such a 'run of storms' a few times this fall, to no avail.  However, if the models verify, planning ahead will prove prudent.  So, what’s the scoop?  

1st.  Rain returns late Wed night, moving in from the NW.  Vancouver Island & southern BC get wet first, then the rain will spread across the rest of the PNW by sunrise Thu Dec 8.  It will be a fast moving front, so expect showers to begin by late Thu.  It will be a cold front, with snow levels dropping again to low elevations once the front passes.  

2nd.  Right behind storm 1 will be a potentially STRONG storm hitting from the West sometime on late Fri / early Sat.  Just where the very deep centered Low moves onshore will determine which area get the strongest WIND FIELD.  Currently, models track No. 2 to make ‘landfall’ somewhere between Coos Bay & Astoria.  BUT, as it moves right up against the OR coast, some solutions literally circle the Low up towards central WA coast, then move it back to Astoria area by Saturday night.  Complicated and very difficult to pin down details.  However, we are not afraid to put out the possibilities; you decide how to plan accordingly.  Quite windy conditions may last hours.  Center pressure could be in the 980s mb and filling to 995 mb by Sat night; some solutions drop the Low to the 970s by Sat morning.  In general, this storm has been on the charts for a few days now, warranting a call-out here.  

3rd.  Yep, another storm - which could be the WETTEST of the series, is modeled to arrive by Mon morning, Dec 12, with the brunt of the storm hitting the region by Tue.  A very deep Low, potentially in the 960s mb!, may form and track just north of Vancouver Island.  The WIND FIELD for this storm will be large, so the PNW could be blown around again, although not as roughly as No. 2.  (Worth the mention: there have been solutions tracking this storm right up against the NW coast of WA; if this scenario were to verify, wind issues will be greatly expanded and stronger than the second system.)

4th.  After a relatively dry Wed and most of Thu, Dec 14,15, another batch of rain will sweep into the PNW late Thu and Fri.  Sat the 17th may be dry, with rain on/off from Sunday into the final week before Christmas.

Lots of changes are inevitable, of course, but for now, it will be prudent to plan ahead in case any or all of these strong storms make it onshore.  The wx this fall has been relatively tranquil, with long stretches between storms.  What is charting now is a rapid succession of storms, some quite powerful, beginning later this week.  Hold on.