textproduct: Medford

DISCUSSION

Showers/t-storms were pretty impressive across the area yesterday afternoon/evening with a ton of lightning moving east-west across Lake/Klamath counties, and also portions of northern Modoc/Siskiyou counties. Several severe thunderstorm warnings were issued, primarily for strong wind gusts to around 60 mph, but also for hail. Many reports along Highway 140 from just west of Lakeview all the way over to Klamath Falls indicated pea to dime size hail that covered the roadways up to 1 inch deep. Indeed, ODOT cameras (tripcheck.com) showed this from Quartz Mountain to Bly Summit. Several reports of trees down and wind damage were also received across the same areas. Rain amounts were also impressive with many locations in NorCal and east of the Cascades getting from 0.50-1.50 inches. It is interesting to note that the lightning pretty much stopped where we thought it would yesterday evening with the Cascades providing the barrier to the much more stable air present over the west side. Rain amounts west of the Cascades were lower, generally 0.10-0.20 of an inch, but nothing to only a few hundredths west of a line from Cave Junction to Grants Pass to Roseburg.

An area of showers is tracking across northern Klamath and Lake counties this morning, with a few embedded thunderstorms tossing out a handful of lightning strikes over the last several hours. These showers are orbiting around a closed low, which satellite imagery shows rotating to the south of the area. Another strong short wave disturbance (in south- central Nevada now) expected to arrive from the ESE this afternoon/evening. The atmosphere will destabilize quickly today, with more showers/thunderstorms ramping up again by mid-late morning over the east side. Models are showing about 600-1200 J/KG CAPE across the area (mainly Cascades eastward), with the highest values maximized from near and just north of Crater Lake and across northern Klamath/Lake counties. Mid-level E flow is still strong this morning (around 30-40 kt) and will persist until mid afternoon. With destabilization, steep mid-level lapse rates and decent shear/forcing with the incoming short wave/PVA, we expect strong convective development during the early-mid afternoon. In the aforementioned areas, some storms could become severe with damaging winds (60+ mph), large hail (1.00"+ diameter), heavy rainfall and lots of cloud to ground lightning. It should be noted that HREF guidance shows 0-3 km storm relative helicity of >200 m2/s2, which is a good indicator of potentially rotating updrafts. Yesterday, one of the more persistent updrafts responsible for many of the severe warning issuances, exhibited rotation for several hours of its life, and there were some reports of rotating cloud formations as it crossed the area. With helicity values stronger today, this presents a low tornado chance (~2-5%) within the strongest cells. Again, the main risk for severe thunderstorms exists from around Crater Lake northward, the Highway 97 corridor north of Chiloquin and across the Christmas Valley, where the Storm Prediction Center has a marginal to slight risk of severe thunderstorms. Easterly flow will once again carry storms off to the west. So, there is some chance at thunderstorms west of the Cascades to around the same areas as yesterday (east of a Cave Junction/Grants Pass/Roseburg line) including Medford/Ashland. General thunder risk also extends southward into NorCal. Any storms in these areas still could contain small hail, gusty winds and heavy rainfall.

By late this afternoon/evening, the orientation of the flow will change and become more northerly. This will maintain an area of rain/showers (with embedded thunder elements early on) from near the Cascades to most of the east side. Once again, many of those areas are expected to receive a total of 0.50-1.50 inches of rain. Shower chances will diminish across the west side, where rain amounts will likely be lower and once again drop off to almost nil closer to the coast.

The closed low will open up into a mid-level trough and finally get a push eastward Friday as upper ridging noses in from the Pacific. As such, shower activity will be greatest in the morning, with coverage gradually diminishing during the afternoon. Even so, there is still some instability over the far east side for a slight chance of thunderstorms (but not even close to how active it was yesterday or will be today).

The next upper trough swings through the area on Saturday, but most areas likely remain dry (outside of S&E sections, where there's still a chance of showers/t-storms). Sunday, PoPs are low (generally 10% or less), so most areas should be dry. Temperatures remain around normal this weekend, but should be a bit higher Sunday compared to Saturday.

Models are consistently showing a warmup early next week -- the degree of which is still uncertain. The majority of the guidance shows highs here in Medford in the upper 80s to near 90F Mon-Wed (peak of warmth on Tuesday) and about 5-10F lower at Klamath Falls. The range of solutions for Medford for Tuesday is 84-96F with a 58% chance of 90F or higher. A reasonable worst-case (90th percentile) would be 94F. -Spilde/BPN

AVIATION...28/18Z TAFS

MVFR ceilings will continue over the valleys with LIFR ceilings over the coast for the remainder of the morning. Some mid level clouds are also moving in, so that will slow down the mixing and burning off of stratus for this morning. We should see VFR conditions develop farther inland this afternoon, although low ceilings will likely persist along the coast through the day.

Convection is also ongoing this morning with some echos and cloud to cloud lightning east of the Cascades. The thunderstorm activity will move westwards into the afternoon hours with the potential of severe storms in northern Lake and Klamath Counties. The probability of severe thunderstorms decreases farther west and south. Klamath Falls has a 40% chance of cloud to ground lightning, or a more generic thunderstorm this afternoon. Gusty winds are the main threat with gusts to 50 mph as a reasonable worst case scenario.

-Smith

MARINE...Updated 900 AM PDT Thursday, May 28, 2026

A long period west-northwest swell will build into the waters this afternoon. This will maintain steep seas, but they'll transition to swell dominated with the easing of winds. Conditions briefly improve early Friday, but increasing north winds on Friday afternoon should support steep to very steep seas through the weekend.

BEACH HAZARDS

Updated 1200 PM PDT Thursday, May 28, 2026...Long period northwest swell, originating from recent storms near the Kamchatka and western Aleutian Islands, will continue to build into the southern Oregon coastal waters. The swell will peak at 6 to 8 feet at around 17 seconds today. The threat will be highest during periods of incoming tides, which will be during the morning, and during the late afternoon and evening.

Sneaker waves can run up significantly farther on beaches than normal, including over rocks and jetties. These waves can suddenly knock people off of their feet and sweep them into the ocean. The waves can also move logs or other objects which could crush or trap anyone caught underneath. Avoid climbing on rocks and jetties. Stay away from the ocean and remain out of the water to avoid hazardous conditions. Never turn your back on the ocean! -Spilde

MFR WATCHES/WARNINGS/ADVISORIES

OR...Beach Hazards Statement through late tonight for ORZ021-022.

CA...None.

PACIFIC COASTAL WATERS...Hazardous Seas Warning until 11 AM PDT this morning for PZZ350-356-370-376.

Small Craft Advisory until 5 AM PDT Friday for PZZ350-356-370- 376.