textproduct: Medford

DISCUSSION

Showers are starting to pop up on radar this afternoon as this low traverses out forecast area. Daytime heating is helping create some instability out there and we should shower coverage continue to increase with perhaps a few embedded thunderstorms. The probability of cloud to ground lightning is about 20% today mainly in California and near the California/Oregon border.

This upper level low eventually lease the forecast area tonight, although there are short waves dropping down from the north west later tonight into tomorrow morning. Main impact will be the continued 50-60% chance of showers on Monday. However, the areal coverage will be lower compared to what we've seen over the last few days. The probability of rain decreases Monday night into Tuesday as high pressure briefly builds. Temperatures remain near normal on Tuesday with some cloud cover entering the forecast ahead of the next system.

By Tuesday night into Wednesday morning, a deep trough and strong cold front will descend upon the Pacific Northwest. Main impacts will be snow accumulation over the higher Cascades Tuesday night into Wednesday morning above 5000 feet. We've issued a winter storm watch because of this threat. Snow levels will drop lower than 5000 feet between Tuesday night through Wednesday, although snow should struggle to accumulate due to warmer ground temperatures with minor snow accumulation around 3500 feet.

The other thing that pushed us to issue a winter storm watch was the extreme forecast index(EFI) painting values of 0.8 along the Cascades. Also, snowfall rates could reach 1" an hour for 6 to perhaps 12 hours along the front. A prolonged period of snowfall rates usually results in some travel impacts. Overall, not a massively impactful storm, although the time of year and the near 1 foot of snow at Crater Lake pushed us towards a winter storm watch. The warmer ground temperatures could really limit the amount of snow accumulation on the other hand like the last event. We'll have to wait and see.

Eventually, the cold front will pass through our forecast area Wednesday afternoon and the precipitation mode will turn showery with minor snow accumulations in the Cascades. The important note will be the colder temperatures moving in behind the front as snow levels crater to 1700 feet!

Usually, we see high pressure set up behind these fronts with a strong inversion build in. However, this looks a bit different as the very cold air off the Ocean should allow for pockets of showers to form with some cloud cover. Temperatures in northern California will drop below freezing due to clearer skies in those valleys. West of the Cascades in Oregon is more uncertain at this time. The chance for Medford to drop below 32F is 34%. The threat of cold overnight lows will continue Thursday night. Conditions are anticipated to remain dry Thursday through Friday before the next system approaches by Friday.

AVIATION (18Z TAFs)

IFR conditions will continue through early this afternoon before relief occurs through the afternoon hours. However, showers are expected again today/tonight and will likely impact all 4 terminals. MVFR conditions are likely (50%-65%) through a majority of this cycle, especially this evening and overnight as showers become likely bringing ceilings down. Otherwise, expecting overall light wind speeds through this cycle, but KLMT could be breezy at times this afternoon.

MARINE...Updated 100 PM PDT Sunday, April 12, 2026

Showers are expected to increase in coverage later today/tonight, but we are not expecting any thunderstorms at this time. The unsettled weather will keep winds and short period northwest swell dominated seas below advisory level through Tuesday morning. Steep seas are possible beginning Tuesday afternoon as a stronger front passes through the region. The front will bring increasing southwest winds as it moves across the waters Tuesday night into early Wednesday. A developing thermal trough inland will bring increasing north winds later Wednesday with the strongest winds south of Gold Beach as seas likely remain steep.

MFR WATCHES/WARNINGS/ADVISORIES

OR...Winter Storm Watch from Tuesday evening through late Wednesday night for ORZ027.

CA...Winter Weather Advisory until 5 PM PDT this afternoon for CAZ080.

PACIFIC COASTAL WATERS...None.