A nice image to see if you like winter weather. Here’s the 24 hour snow accumulation forecast from the UW-WRFGFS model. The red areas represent maybe 10″ of snow. This is the 00z run that just came out. The 12z (morning) run showed the heavy snow area farther north and east, centered over the Wallowas. So SOME area in our region is probably going to get a good dumping of snow. As a result PDT NWS folks have a winter storm watch out for the mountains of Central and NE Oregon.
It is a nice cold trough dropping south. It spins up a surface low tomorrow night somewhere near Pendleton or the Tri Cities. Gusty northeast wind pours out through eastern Washington and then moves down into our area (as light northeast wind) during the day on Sunday. Dry (but not really cool) air continues moving south over us on Monday. This offshore flow and sunshine should push temps back up around 70 both days. A real quick dropoff in overnight temps probably means the first frost of the season in the outlying areas Monday and/or Tuesday mornings.
The rest of next week looks incredibly nice for early October. Warmer days and cool, crispy nights. 850mb temps support highs getting close to 80 next Wednesday-Friday, depending on the strength of the offshore flow. It appears that cold high pressure sliding down to our east is going to stay well to the east, keeping any cooler air influence way out east of the Continental Divide. Enjoy it while it lasts, all models seem to show some very wet weather beginning next weekend (at the earliest).
Chief Meteorologist – Mark Nelsen