Marine Weather and Tide Forecast for Harbor, OR

AVIATION
08/00Z TAFs...Satellite imagery shows a distinct front to the north. Expect a mix of MVFR/VFR (NW of the Cascades/Siskiyous) as the front presses from northwest to southeast this afternoon/evening. While moisture is limited with the front, it'll bring a healthy marine push tonight with more widespread MVFR (local IFR/LIFR) ceilings, higher terrain obscurations and perhaps a period of very light precipitation along and to the north/west of the Siskiyous/Cascades (40-60% chance). Best chance of precip will be on north-facing slopes. Here in Medford, precipitation chances are lower, about 10-20% and there is some uncertainty if the ceiling will even lower to MVFR. There is about a 40% chance of that occurring late tonight or first thing Monday morning (2500 ft or so). Some improvement is possible along the coast later tonight or Monday morning, but there could still be some light rain/sprinkles.
We do expect improvement to VFR in most of these areas late Monday morning/afternoon, but some MVFR ceilings could persist NW of the Umpqua Divide.

For areas south and east of the Cascades/Siskiyous, aside from patchy MVFR ceilings very late tonight and prior to noon Monday, VFR should prevail. -Spilde/BR-y

PREV DISCUSSION
/Issued 227 PM PDT Sun Mar 8 2026/

DISCUSSION...Early morning fog has cleared out of west side valleys, allowing for generally clear skies and warm temperatures this afternoon. Daytime highs above seasonal norms remain in the forecast across the area, with the warmest temperatures in low-lying areas across Siskiyou and Modoc counties.

Onshore flow may help marine stratus or fog return tonight into Monday morning. Valley fog is more questionable, as this flow aloft looks to push moisture farther inland. This moisture can work against fog by insulating inland areas overnight, preventing radiative cooling that allows fog to develop. Any light rain showers that fall can provide enough mixing to limit fog development as well. And the upper pattern looks to change from under a ridge to zonal flow, which would increase instability (if only slightly). So while patchy fog is possible, fog to the extent of Saturday night/Sunday morning is unlikely.

That zonal flow pattern will guide moisture to the Pacific coast through much of the forecast period, although much of the activity is expected to stay north of the area. Slight precipitation chances (20-40%) are present along coastal areas north of Cape Blanco and over Douglas county to the Cascades to acknowledge the chance of some moisture moving far enough south to bring light showers. But overall, precipitation expectations are minimal through midweek. In addition to this area being south of the moisture flow, an absence of atmospheric mechanisms would make any showers rely on orographic lift. This would generally keep any showers that do develop over coastal ranges or the Cascades. A compact gradient between a low pressure system in the Gulf of Alaska and a Pacific ridge will allow for breezy to gusty winds over area terrain in the afternoon and evening, but these winds remain short of Advisory speeds.

To look at some specifics in the week ahead, the developing zonal flow will allow for cold air advection tonight through Tuesday night. During the day, high temperatures are forecast to be below seasonal norms. At night, cool low temperatures may cause some local impacts. Monday night into Tuesday morning will have the coolest overnight lows of the forecast period. Some coastal areas may see lows of 33 to 36 degrees, which would support frosty conditions.
These temperatures are only present briefly in the forecast, so there is not the confidence to issue any full products at this point. West side valleys look to be in the low 30s, while east side areas will be in the mid teens to low 20s. With this cold air, forecast snow levels drop to 1000-2000 feet on Tuesday night. Given the broad area of slight precipitation chances, snowfall may be indicated. However, these chances are best over areas terrain and water amounts will be measured in the hundreths. Winter impacts are expected to be nonexistent.

For the middle to end of the week, fronts from the low pressure system in the Gulf of Alaska look to pass to the north but may push on the zonal flow aloft. This could bring the atmospheric moisture stream closer, bringing shower chances over Curry County and increasing them over Coos and Douglas counties to the Cascades. With snow levels forecast to be back up to the 6000+ foot range by this point, any snowfall would be limited to area peaks and ridgelines.

Overall, possible variations in atmospheric moisture and upper ridge/trough position add some uncertainty to the details of the forecast. However, widespread hazardous conditions are not expected through the week ahead without a significant shift in forecast conditions. -TAD

MARINE
Updated 230 PM PDT Sunday, March 8, 2026
Through Monday night, advisory level north winds and steep, choppy seas are expected south of Port Orford with lighter winds and lower seas to the north. We have upgraded the hazardous seas watch to a warning for very steep, short period seas (10-11 ft at 7 seconds)
south of Gold Beach Monday afternoon and evening due to stronger north winds. Improving conditions are possible on Tuesday as the dominant wind seas transition to west-northwesterly swell. Even so, the WNW swell arriving will be borderline for small craft advisory (10 ft at 12-13 seconds). This swell decays Tuesday night into Wednesday with winds shifting to SW. Mid-late week, guidance shows a front stalling nearby to the north. This would keep the core of the windier, more unsettled weather to the north, but with additional westerly swells moving through.

MFR WATCHES/WARNINGS/ADVISORIES
OR
CA
None.

PACIFIC COASTAL WATERS...Small Craft Advisory until 5 AM PDT Tuesday for PZZ356-376.

Hazardous Seas Warning from 11 AM Monday to 5 AM PDT Tuesday for PZZ356-376.