986 FXUS66 KMFR 121548 AFDMFR Area Forecast Discussion National Weather Service Medford OR 848 AM PDT Wed Apr 12 2023 .DISCUSSION...The latest visible image clearly shows a weak cyclonic circulation over the marine waters and is moving towards Coos Bay. Plenty of cold air aloft is evident by the popcorn configuration of clouds offshore. Showers this morning will be isolated, then will increase in coverage this afternoon due to daytime heating and the upper low moving overhead. Even then, showers will be light, but a few could be moderate at times. The freezing level on this mornings sounding was 3400 feet which will put the snow level between 2000 and 2500 feet this morning, but there will be a diurnal rise during the day and end up between 3000 and 3500 feet later this afternoon. Therefore adjustments were made to the weather, and snow level portion of the forecast today. For details on the rest ofthe forecast, please see the previous discussion. -Petrucelli && .AVIATION...12/12Z TAFs...Numerous showers are expected across the area today, especially from the Cascades west. From the Cascades west, expect areas of MVFR ceilings through this morning, becoming VFR in the afternoon and evening. VFR with isolated MVFR conditions are expected east of the Cascades in showers. Areas eastside could see gusts near 30 to 35 mph late morning and through the day. -CC && .MARINE...Updated 800 AM PDT Wednesday, April 12, 2023... Steep northwest seas and gusty northwest winds will persist across the waters today. A thermal trough will develop over northern California this evening and tonight. Winds will become northerly with the strongest winds south of Cape Blanco. Steep seas will persist across the waters through tonight. Weaker winds and lower seas will follow Thursday into Saturday with weak high pressure over the region. A slow moving front will be the first in series of disturbances Sunday through early next week, with steep to very steep seas likely and gales possible. -CC/Spilde && .PREV DISCUSSION... /Issued 303 AM PDT Wed Apr 12 2023/ DISCUSSION...The upper level trough axis will swing overhead today, with showers expected across much of the region through this evening. Shower activity will be most rigorous across the West Side during the afternoon, when daytime heating peaks and the coldest air will be aloft, and therefore instability will be highest. Snow levels of 1500-2000 feet are forecast, along with a small chance for a few of the stronger showers to produce a roll of thunder or two. Throw some locally lower snow levels under those stronger showers, as well as some graupel, and it seems an interesting spring weather day is in store. Ridging will build into the area Thursday, leading to a dry, warming trend through Saturday night. Before we get there, however, Thursday morning should see the coldest temperatures of the week, with clear skies overhead and the residual cooler air still lingering behind the departing trough. While the growing season has had a slow start west of the Cascades, some agriculture has started, so frost will be a concern late tonight into Thursday morning, and to a lesser degree Thursday night into Friday morning. Otherwise, it will be quiet through the first half of the weekend with mostly seasonable weather. By the end of the weekend, a large upper level trough over the Gulf of Alaska will dig into the Pacific Northwest. At this point, the ensemble suites show a wide spread of solutions, so any details, especially in timing, are very uncertain. What is clear, however, is that we are very highly likely going to see a return to cooler and wetter weather for the first part of next week. -BPN && .MFR WATCHES/WARNINGS/ADVISORIES... OR...CA...None. PACIFIC COASTAL WATERS...Small Craft Advisory until 5 AM PDT Thursday for PZZ350-356-370-376. && $$