190 FXUS66 KMFR 111605 AFDMFR Area Forecast Discussion National Weather Service Medford OR 905 AM PDT Thu Oct 11 2018 .DISCUSSION...Current observations are showing a few marine layer clouds in the Umpqua basin as well as in the klamath Basin in Lake County. A few places saw some heavy frost, as per the frost advisory (and some places that weren't included), but this frost is quickly dissipating, and have allowed the frost advisory to expire. The benign pattern continues for the foreseeable future, but will need to take a closer look at temperatures for tonight. We do have a freeze warning and frost advisory in effect, but will need to refine the low temperatures tonight as it seems lows have been coming in lower than guidance. The other forecast challenge will be a shortwave wobble on Sunday. This could create gusty winds and dry conditions across southern Oregon and northern California which could have some impacts for anyone doing prescribed burns. More info will come in the afternoon package. For now, the previous discussion is included below and describes the forecast (including the marine forecast) quite well. -Schaaf && .PREV DISCUSSION... /Issued 359 AM PDT Thu Oct 11 2018/ DISCUSSION...An upper level ridge is nosing into the Pacific Northwest today with a trough axis shifting south and east of the area. A piece of the trough will break off and meander to a position just off the Southern California coast by Friday. Meanwhile, the upper ridge will amplify over the eastern Pacific with an upstream trough extending from just north of Hawaii to the Aleutians. This is resulting in a pretty classic omega blocking pattern, which will ultimately prevent any significant weather systems from impacting the West Coast through much of next week. What this means for us is a long stretch of dry mid-October weather with temperatures that will average a few to several degrees above normal. Much of that time will be characterized by chilly nights (cold east side) and seasonably mild to warm afternoons. Strong late-night and early morning inversions will result in areas of frost in sheltered west side valleys, especially portions of the Rogue, Illinois and Applegate Valleys, while surrounding mid slopes ridges will be comparatively warmer. Frost/freeze headlines are in effect for this morning and again late tonight into Friday morning. Details of these can be viewed at NPWMFR. Additional headlines for valley frost/freezing conditions may be necessary this weekend. Periods of breezy east to northeast winds will bring warmth to coastal areas near Brookings for the next several days with highs in the 70s and even the low 80s. One disturbance will come over top of the ridge and down the east side Saturday into Sunday. While this system is likely to bring some gusty north to northeast winds Saturday afternoon/evening and also briefly halt the warm-up east of the Cascades, it could go largely unnoticed west of the Cascades. In fact, the flow may turn offshore enough by Sunday to bring warmth to coastal areas north of Cape Blanco, including Bandon/Coos Bay/North Bend with highs in the mid to upper 70s. -Spilde AVIATION...For the 11/06Z TAFs...VFR conditions are being observed in most places now. Fog is hugging the coast near Cape Blanco and could impact KOTH briefly tonight before drier air moves in and VFR conditions become predominant. Drier conditions compared to last night should keep KRBG and other West Side valleys VFR tonight. East of the Cascades, MVFR ceilings are expected in Lake County with clearing in the late morning. -Schaaf/Keene MARINE...Updated 3 AM PDT Thursday 11 October 2018...A thermal trough near the coast will maintain gusty north winds and steep seas from Cape Blanco southward through Friday. This area of Small Craft Advisory conditions will expand northward Friday afternoon into Saturday. Additionally, long period southerly swell will build tonight, then persist at a peak Thursday into Friday. This may bring rough bar conditions at Brookings and elevated surf at Port Orford. On Sunday, expect the region of strongest northerly winds to shift to the outer waters north of Cape Blanco with seas gradually lowering into Tuesday. Towards next week Thursday, we'll see a long period westerly swell move into the outer waters. We're not expecting any issues with this new swell group as wave heights will probably stay below 10 feet. -Keene/Smith && .MFR WATCHES/WARNINGS/ADVISORIES... OR...Frost Advisory until 9 AM PDT this morning for ORZ024-026. Frost Advisory from 2 AM to 8 AM PDT Friday for ORZ024-026. Freeze Warning from 2 AM to 8 AM PDT Friday for ORZ024-026. CA...None. Pacific Coastal Waters...Small Craft Advisory until 11 PM PDT Saturday for PZZ356-376. Small Craft Advisory from 2 PM Friday to 11 PM PDT Saturday for PZZ350. Small Craft Advisory until 11 PM PDT Saturday for PZZ370. $$