textproduct: Medford

DISCUSSION

Updated aviation and marine discussions.

AVIATION...20/18Z TAFs

Low pressure offshore will bring rain and lower ceilings (mixed VFR/MVFR) at the coast and in portions of western Siskiyou County through this afternoon. Areas of higher terrain will become obscured. Inland areas will remain mainly VFR the rest of today, then areas of MVFR (and terrain obscuration) will spread inland to areas west of the Cascades this evening and overnight. Gusty south to southeast winds are expected in the Shasta Valley, the Rogue Valley up to around Medford and over the East Side late this morning into this afternoon. Expect peak wind gusts of 25- 30 kt, but perhaps 35 kt. We'll be monitoring for possible airport weather warnings at both Medford and Klamath Falls. The increasing southerly flow into Siskiyou County, including the Mt Shasta region, will cause lowering ceilings (to MVFR) late this afternoon and then persist tonight along with rain and high elevation snow (above 5000 feet). Some IFR is possible down there as well. Precipitation will be more showery north of the Siskiyous. These conditions last into Tuesday morning, then expect additional showers Tuesday afternoon, along with a slight chance of thunderstorms. -Spilde

MARINE...Updated 950 AM PDT Monday, April 20, 2026

Low pressure will bring active weather through this evening, with gusty south winds, elevated seas, periods of rain and low visibility. Winds are likely to be strongest through this evening with a period of steep seas hazardous to small craft mostly beyond 10 NM from shore and for areas within 10 NM of shore from Cape Blanco north. Conditions should improve Tuesday as the low gradually pushes into Northern California. Then, increasing NW swell follows Wednesday into Thursday with a return of north to northwest winds. -Spilde

PREV DISCUSSION

/Issued 627 AM PDT Mon Apr 20 2026/

DISCUSSION...

Key Points:

* Only minor impacts expected the next several days * Low pressure off the coast will bring winds and precipitation - Precipitation gradually spreads inland today and tonight, with showers persisting through Wednesday. - Breezy to gusty winds today, locally strong. - Isolated thunderstorms possible on Tuesday. - Advisory snowfall for mountains in Siskiyou County Mon- Tues * Drying trend towards the end of the week

An upper low offshore will approach the coast of southern Oregon and northern California late today, then remain just off the coast Tuesday before gradually moving inland across the region Tuesday night and Wednesday.

This low will send southerly moisture into the area today with showers spreading inland from the coast to the Cascades . Winds will increase out of the south today with breezy to gusty conditions affecting the area. Strong winds are expected in the Shasta Valley with gusts up to 50 mph. A wind advisory (NPWMFR) is in effect for this area. Gusty winds are also expected over higher mountains and east of the Cascades (gusts of 30 to 40 mph). Precipitation will initially spread along the coast this morning then inland during the day with the most widespread precipitation across Curry county and southern and western Siskiyou County with more showery precipitation elsewhere.

Precipitation will be generally light to locally moderate with this system but expect showers to continue through Wednesday as the low gradually moves onshore and inland. Although initially areas from the Cascades west will be affected today, tonight and Tuesday, showers will spread inland across the area. The models and ensembles shower that showers will persist through Wednesday. Heaviest amounts over the next 3 days are expected across western/southern Siskiyou County (1-2 inches) with moderate precipitation (0.5-1.0) in Curry County, southern Josephine County and the southern Oregon Cascades and Siskiyous. With lowering snow levels tonight into Tuesday (5000-6000 feet), expect mainly light snow accumulations in the Cascades (1-5") and mountains in Siskiyou County. One area that may see higher snowfall amounts is the the mountains near the Trinity Alps in SisKIyou County, including south of Callahan. A winter weather advisory is in effect for this area. Please see the WSWMFR for details.

In addition to rain and mountain snow, there is a slight chance (15-20%) for thunderstorms from the Cascades west on Tuesday afternoon as well. Models continue to show MUCAPE values on Tuesday continue of around 100-500 J/kg, so we are expecting at least some isolated thunder. East of the Cascades, chances for thunderstorms are around 10% on Tuesday. MUCAPE on Wednesday is lower so chances for lightning are lower (5-10%). Not expecting any severe weather but lightning and occasional strong gusts (30-45 mph) will be possible through this stretch.

Breezy winds are expected on Tuesday then winds increase slightly on Wednesday with gusty winds (25-35 mph) expected east of the Cascades.

By Thursday, upper level low will be absorbed back into the main flow. A dry north/northwesterly flow will become evident over the forecast area. While the National Blend of Models holds onto spotty PoPs Thursday onward, we are anticipating precipitation chances to dwindle Thursday and Thursday night. Model differences in the extended come to fruition around Friday night as an upper level trough drops down from the north and into the region. However, there are significant differences on the track and strength of this trough. So confidence is low on the details for Friday into the weekend.

AVIATION...20/12Z TAFs...Rain and lower ceilings (to MVFR) will spread onto the coast this morning. Inland areas will remain mainly VFR today, then areas of MVFR ceilings spreading inland to areas west of the Cascades this evening and tonight. Winds will increase again later this morning and this afternoon for similar locations as yesterday (Shasta Valley, Medford and the East Side). Increasing southerly flow into Siskiyou County, including the Mt Shasta region, may cause lowering ceilings (to MVFR) beginning late this afternoon and continuing tonight along with rain and high elevation snow (above 5000 feet). Precipitation will be more showery north of the Siskiyous.

MARINE...Updated 100 AM PDT Monday, April 20, 2026...Low pressure offshore will bring a period of active weather today into tonight, with periods of gusty south winds and elevated seas/swell. Winds are likely to be strongest through this evening with a period of steep seas hazardous to small craft mostly beyond 10 NM from shore and for areas within 10 NM of shore from Cape Blanco north. Conditions should improve Tuesday as the low gradually pushes into Northern California. Then, increasing NW swell follows Wednesday into Thursday with a return of north to northwest winds.

MFR WATCHES/WARNINGS/ADVISORIES

OR...None.

CA...Winter Weather Advisory until 11 AM PDT Tuesday for CAZ080>082.

Wind Advisory until 6 PM PDT this evening for CAZ081.

PACIFIC COASTAL WATERS...Small Craft Advisory from 1 PM this afternoon to 8 PM PDT this evening for PZZ350.

Small Craft Advisory until 8 PM PDT this evening for PZZ370-376.