Marine Weather and Tide Forecast for Dallas, OR

SHORT TERM
Tonight through Sunday...Radar and satellite imagery shows lingering shower activity has remained fairly isolated this afternoon, primarily confined to the higher terrain of the coast range/Cascades, likely persisting into the evening hours before drier weather returns. Another weak and progressive trough will pass over the region early on Friday with almost all areas remaining dry locally due to a lack of moisture/upper-level forcing. By Friday afternoon, heights aloft will begin to rise in earnest as longwave ridging begins to build over much of the western CONUS. Temperatures jump into the 60s and 70s Friday afternoon which is right around normal.
This warming trend continues into Saturday as well with the axis of the amplifying upper-level ridge passing west to east over the Cascades leading to another 5-8 degree jump in high temperatures. Confidence is high for maximum temperatures rising into the mid 70s to near 80 along the I-5 corridor and other inland valleys Saturday afternoon, above normal for late May.

Late Sunday chances begin to increase for a brief breakdown in upper ridging as an increasing number of ensemble and deterministic models favor a negatively-tilted shortwave trough undercutting the ridge, before potentially becoming cutoff over California.
Given the warm antecedent conditions and advection of a mid- level moisture layer preceding the trough, thunderstorms remain a possibility (15-20%) late Sunday afternoon, mostly near the crests of the Cascades eastward. Models like the GFS/NAM currently show around 200-600 j/kg of MUCAPE in this region but the exact timing of shortwave forcing will determine the extent of convective development; a delay of this feature further into the evening hours would keep activity weaker and pushed to the east. Still, it's definitely worth paying attention to if you plan on venturing outdoors for the holiday weekend, especially the Cascades.

LONG TERM
Monday through Thursday...Ensemble and deterministic guidance generally depict the axis of the aforementioned upper-level trough with the attendant cut-off low to our south passing overhead on Monday leading to a slight chance for showers in the interior valleys but better probabilities for activity along the coast/coast range and Cascades due to more advantageous orographic forcing. Still, exploring the NBM an other ensemble products overall rainfall accumulation during this period looks rather low, <0.05-0.1" for the Willamette Valley, 0.05-0.2" coast/coast range, and 0.1-0.3" Cascades. Resurgent ridging into Tuesday would then see a quick return to warm and dry weather across the region. Then, confidence rapidly decreases Wednesday and beyond as ensemble spread increases dramatically. Persistent ridging could see a prolonged period of warm to hot temperatures and dry weather continue (50% of ensemble members), while a breakdown of the ridge could instead see a return to cooler and wetter conditions (also ~50% of ensemble members). This has resulted in a nearly 30 degree temperature spread (ranging from 65 to 95 degrees)
between the NBM 10th and 90th percentile for the potential high on Wednesday. The current forecast sits in between (upper 70s to mid 80s) with hopefully better model agreement in the coming days increasing forecast confidence. -Schuldt

AVIATION
Onshore flow will maintain broken to overcast mid level clouds through tonight, with more clearing expected on Friday. As of 20z Thursday, predominately VFR conditions with MVFR CIGs lingering at a few locations. Coastal sites have a 50-60% chance of MVFR CIGs returning around 04-06z Friday. Winds remain onshore and generally less than 10 kt. /DH

PDX AND APPROACHES...Predominately VFR conditions expected through the TAF period with broken mid level clouds. Northwest winds expected around 4-6 kts. /DH

MARINE
Weak high pressure offshore will maintain north to northwesterly breezes across the coastal waters into the weekend.
Winds generally remain below 10-15 kt, though inland daytime heating could drive the diurnal strengthening of the pressure gradient, allowing winds to gust up to 20 kt along the nearshore waters. Seas will persist around 3 to 4 ft through Saturday. By early Sunday, winds turn southerly ahead of a weak front, increasing through the day, but expected to remain below 20 kt. A northwest swell will also build seas to around 6 to 7 ft. /DH



PQR WATCHES/WARNINGS/ADVISORIES
OR...None.
WA...None.
PZ...None.