Downslope Wind

December 28, 2006

It’s a windy night across the metro area as our Gorge easterly wind appears to have started as a downslope wind event instead.  Massive increase in gradient this evening to around 10 millibars PDX-DLS.  That was well forecast by models.  But the sure signs of easterly downslope wind are (in my book):  1) I have east wind at my home east of Corbett, that only happens with downslope wind, usually my "east" wind comes around a hill from the northwest.  2) Brightwood has a gusty east wind.  3) Our rooftop sensor just recorded a gust to 34 mph at 10:45pm.  We only get strong east wind at KPTV at Cornell & Hwy. 26 with the downslope winds.  4)  Dewpoints lower at HIO, VUO, PDX than TTD.  If the cold/dry air was only coming out of the Gorge dewpoints shouldn’t get drier as you get AWAY from the Gorge should it?

System approaching may hang together enough for light precip west of the Cascades tomorrow…maybe not, tough call.

Splitting/ridge pattern holds through at least Sunday.  Some models have precip in here by Monday (ECMWF), but new 00z GFS is dry until Wednesday!  I’ll leave any changes to the 7 Day for Drew in the morning.   Or I could just write "Long Term…no Changes" for my NWS friends.  If the Thursday-Friday chilly 850mb temps hold in future model runs it will be cooler than what my 7 Day shows too…Mark