Active Weather Ahead

December 13, 2007

SnapshotFinally, the slow weather is going to come to an end over the next few days.  A mix of low level fog along with higher clouds again tonight.  I’m thinking that increasing cloud cover overnight actually should lift the fog a bit by morning.
Tomorrow should be another gray day with a mix of fog and clouds.  00z models are more insistent on holding off cold-front related rain until well after sunset Friday, even at the Coast.  This system races inland with maybe .20-.40" in the Valleys and double that in the mountains by Saturday morning.  The strong westerly flow opening up behind the front should squeeze all available moisture out of the airmass Saturday in the mountains.  When the flow runs perpendicular into the mountains, we get good snow totals.  Maybe a foot total from tomorrow evening into Sunday A.M.
The next system is looking quite a bit stronger for Sunday.  In fact I had already imported this coast graphic before I saw the 00z MM5-NAM & GFS versions both have 45 knot surface wind moving onto the Coastline during the day on Sunday (I’m watching these things closely for some reason).  So we may end up with 60 mph gusts easily if trends continue out there.
This illustrates a good point for next week;  with a fast westerly flow and numerous shortwaves moving through, expect frequent model changes with respect to low pressure centers and "wind zones".  For that matter, the snow level is relatively low (2,000′?) several times during the upcoming week, so we need to keep an eye out for any "offshore" flow events that could lower the snow level farther.  That said…nothing really sticks out at me on the maps as a big wind storm or snow event through the middle of next week.  But keep tuned!  Mark Nelsen