The upper level low continues to track to the south off the Oregon Coast today. The center of the low is still far enough north of our region to keep the moist onshore flow intact. Because of this, we are still seeing isolated shower activity throughout our area. As the low continues south winds will begin shifting from the southwest to the south. On Tuesday, the low will move onshore when it reaches Northern California shifting the winds out of the east for Southern Oregon. The cooler and drier air aloft with this system is creating instability. Instability in the region is responsible for the thunderstorms that we will get with this system.
Over the last 12 hours, rainfall totals have been minimal only seeing a little over a half an inch in some locations. However, showers have been numerous. This means that we’ve been getting short periods of isolated showers. Sunday morning showers decreased leaving mostly fair weather cumulus across some locations. Rain remained steady along the coast and in the mountains. Snow levels were down to 6,000′ Sunday allowing for mostly a rain and snow mix in the upper elevations. No accumulation however, as temperatures remained above the freezing level.
Shower activity picked up in the afternoon of Sunday. Instability was not as strong Sunday so not many thunderstorms occurred in our region. However, lightning was seen to the north and northeast of our watch area. Cooler air will move in Monday allowing for a better setup for isolated thunderstorms. All areas will have the conditions to experience a chance of thunderstorms. Showers will pick up in the afternoon on Monday. This is when the heaviest of rainfall is expected with this system. Updrafts will be moderate in these thunderstorms so I will not rule out the possibility of small hail in the region. It’s important to keep in mind that not all areas will experience these storms as they will be isolated in nature.
By Tuesday, as the low moves inland to the south of Oregon, winds will shift to the east creating a wrap-around effect. This will keep rain and thunderstorm chances up for South Klamath and Lake Counties and Northern California. Another round of isolated shower activity will occur in the Cascades and Siskiyous Tuesday afternoon. This will be the end of the precipitation with this system. High pressure is set to build in and by Wednesday we will see temperatures warming and skies clearing.
Thanks for logging on and have a good week!