Marine Weather and Tide Forecast for Cliffdell, WA

PREV DISCUSSION
/issued 459 AM PDT Tue May 13 2025/

SHORT TERM
Today through Thursday

1. Widespread rain through Wednesday morning becoming dry

2. Afternoon thunderstorms today

3. Breezy gap winds today and Wednesday

Current radar shows showers over the eastern mountains with ground observations showing 0.02-0.05 inches of rain has fallen over those areas in the last 3 hours. Current nighttime satellite shows the region to still be under clouds with the exception of a few isolated locations.

Models show the axis of the upper level trough to be mostly off to the east with the backside of the trough bringing some lingering showers to the Cascades and eastern mountains. 24 hour raw ensembles show the precipitation amounts to be slightly less with 60-80% probabilities of 0.10-0.15 inches of rainfall along the eastern mountains and the OR Cascades, while the Basin and foothills have a 40-60% chance of 0.05-0.10 inches of rainfall. Models show the leading edge of an upper level dirty ridge to begin sliding in over the PacNW by Wednesday early morning which will keep some linger showers over the Cascades and Blues until the afternoon when conditions dry out through Thursday afternoon before models show another upper level trough making its way to the PacNW.

Today there is not as much instability over the region as the low pulls farther to the east. However, raw ensembles still show a 10- 15% probability of thunderstorms along the eastern mountains with 20- 30% mainly over the far eastern quadrant of Wallowa County with MUCAPE values over 250-3 50 J/kg, surface lapse rates of 8.2 C/km, mid level lapse rates of 7.3 C/km and lifted index of -2. This, coupled with the orographic lift with the upper level southwest winds aloft, we cannot rule out the probabilities of thunderstorms over the eastern mountains this afternoon.

Lastly, winds will be elevated each day, especially through the mountain gaps. Surface level cold air advection will be the root cause of the pressure gradient increase across the Cascades heightened by the upper level trough. Models show winds to be strongest through the Gorge with 50-80% probabilities of gusts to 35 mph. Kittitas Valley will also see breezy conditions with 30-60% probabilities of 30 mph gusts today. Pressure gradients tighten tomorrow as a shortwave ripples down the front edge of the upper level ridge. 60-80% of the raw ensembles show the Gorge and Kittitas Valley seeing gusts between 35 to 40 mph. Winds will settle as the upper level ridge continues to push across the region with raw ensembles showing 60-80% probabilities of only 15-20 mph gusts.
While this is nothing new for the area, please be mindful of the winds while driving through the mountain gaps (I-84 & I-90) today and tomorrow. Bennese/90

LONG TERM
Friday through Tuesday
Sensible weather concerns through the extended forecast will center around the passage of an upper level trough over the weekend, resulting in periods of breezy winds, rain showers, and afternoon thunderstorm chances.

Ensemble cluster guidance is in good agreement that Friday will start with a shortwave in transit over the region producing showers across the Cascade crest and the eastern mountains. The shortwave will exit the area by the late morning hours, but very light isolated showers will continue across the Cascade crest, northern Blues, and the Eagle Caps through the remainder of the afternoon.

Friday night through Saturday, ensemble cluster guidance continues to be in good agreement that an upper trough will dive into the PacNW from the northeastern Pacific. This will bring increased shower activity across the forecast area, with the bulk of the precipitation occurring over the Cascades and eastern mountains.
Ensemble guidance also indicates increasing instability across the eastern mountains, central OR, and along the Cascade east slopes Saturday afternoon, with a 15-20% chance of isolated thunderstorms developing over these areas. The upper trough passage will also produce a tightening surface pressure gradient Saturday, resulting in breezy to locally gusty conditions through the Cascade gaps, and breezy conditions in portions of the Lower Columbia Basin and central OR. The upper trough will continue to push east Sunday with about 55% of ensemble cluster members (from the ECMWF, GFS, Canadian) indicating the trough developing into a closed low to the southeast of the forecast area by the afternoon. While a majority of the members (~75%) push the trough/low to the windward side of the Rockies with shower activity limited to the higher terrain of the northern Blues, Cascade crest, and the Eagle Caps, the remaining members keep the low/trough closer to the forecast area, resulting in light showers continuing across most of the eastern mountains as well as the Cascade east slopes. Confidence is overall moderate (50-65%) that showers will continue across the Cascade crest, northern Blues, and Eagle Caps through Sunday, with low confidence (25-35%) across the remainder of the mountain zones.

Sunday night into Monday, ensemble guidance is in good agreement that the upper trough/low will continue to push east of the region with broad upper level ridging developing off the coast of CA.
This will place the PacNW in a nearly zonal flow aloft with a signal for shortwave impulses passing over the region through Monday. These shortwaves will be strong enough to result in light isolated showers over the Cascade crest and the northern Blues.

With persistent upper level troughing impacting the forecast area through the extended forecast, confidence is moderate (50-70%)
that afternoon temperatures in the lower elevations will generally be in the 60s to lower 70s, with mid 40s to 50s mountains through the period. Surface pressure gradients will remain tight across the forecast area Sunday through Monday, which will allow breezy to locally gusty winds to develop through the Cascade gaps and into the Columbia Basin and central OR. Confidence is moderate (60-70%) that strongest wind gusts between 35-45mph will be confined to the eastern Columbia River Gorge and the Kittitas valley. Lawhorn/82

PRELIMINARY POINT TEMPS/POPS
PDT 64 45 66 41 / 40 30 0 0 ALW 63 47 65 44 / 40 30 0 0 PSC 71 45 73 41 / 20 20 0 0 YKM 72 45 71 41 / 20 10 0 0 HRI 70 46 70 42 / 30 20 0 0 ELN 68 45 64 41 / 20 10 0 0 RDM 60 35 61 32 / 20 10 0 0 LGD 56 43 59 37 / 50 40 0 0 GCD 56 40 58 34 / 60 60 0 0 DLS 68 47 66 44 / 10 0 0 0

PDT WATCHES/WARNINGS/ADVISORIES
OR...None.
WA...None.