Warm, Dry Start to the Week Expected Before Midweek Storm Brings Rain

Medford, Oregon- High pressure is building over the region today, setting the stage for a period of warmer and mostly dry weather across southern Oregon and northern California. A warm front passing to the north may produce isolated showers (20-30% chance) in the coastal areas and northern Douglas County, but most areas are expected to remain dry. Low clouds and fog this morning will give way to increasing sunshine this afternoon, with temperatures rising above seasonal averages.

Highs today are expected to reach the low to mid-60s in the west side valleys, with temperatures nearing 70°F in the lower Klamath Basin near Happy Camp. East side locations will see highs mainly in the mid to upper 50s, though some areas near Alturas in northeastern California may approach the low 60s.

An upper-level ridge will strengthen as it drifts across southern California and into the Great Basin and Pacific Northwest early this week, bringing two warm spring days on Monday and Tuesday. Highs on Monday are forecast to be 10-15 degrees above normal, with temperatures in the low to mid-70s in Medford and other west side valleys, and between 60°F and 70°F on the east side.

Tuesday is expected to be the warmest day of the week, with highs 15-20 degrees above normal. Medford could tie its record high of 80°F set in 1997, with a 75% chance of hitting or exceeding that mark. Other potential record-breaking highs include Montague (78°F, 1960), Alturas (79°F, 1960), Roseburg (73°F, 2015), Klamath Falls (73°F, 1960), and Mt. Shasta City (74°F, 1997).

By Tuesday evening, the ridge will shift eastward as an upper trough approaches the coast. A weak shortwave disturbance could trigger isolated showers over western Siskiyou County and parts of southwest Oregon after 5 p.m., though the chance of thunderstorms remains low at less than 15%.

Wednesday is expected to remain warm despite increasing cloud cover from the approaching trough. Highs in the low 70s are still possible in the west side valleys. Strengthening pressure gradients will lead to breezy to windy conditions, with potentially strong south winds in the Shasta Valley, northeastern California, and the east side. The chance of precipitation increases to 60-90% by Wednesday afternoon and evening, especially west of the Cascades as a cold front moves toward the coast. A slight chance of thunderstorms exists near the Cascades, northwest Klamath County, and Mt. Shasta City.

The cold front will push inland Wednesday night into Thursday, with snow levels dropping from above 8,000 feet to around 4,000 to 4,500 feet by Thursday morning. Light snow accumulations are possible in the higher elevations and mountain passes.

An upper trough near the coast of British Columbia will maintain an unsettled pattern through Thursday and Friday, with onshore flow bringing additional weather systems into the region. A brief break is possible Saturday before another, more potent system arrives Saturday night or Sunday.

Forecasters are also monitoring the potential for heavy rain and snow during the first week of April, which could elevate river levels due to spring snowmelt and additional rainfall.