textproduct: Portland

SYNOPSIS

Warm and dry conditions continue today, but temperatures are expected to gradually moderate toward August norms by Sunday, continuing into early next week. Renewed onshore flow will keep smoke east of the Cascades. Precipitation is not expected during the next week across the area.

DISCUSSION...Today through Thursday

The upper level ridge axis continues to shift east today, with broadening of the ridge eventually flattening out over the weekend. This will lead to a gradual cooling trend to near normal August temperatures by Sunday. Another strong push of onshore winds later this afternoon will continue to scour out the smoke and haze in the area.

High temperatures today remain on the warmer side, reaching into the mid to upper 80s inland, with a few locations potentially reaching 90 degrees. Stratus along the coast should scatter out in the afternoon before the next marine push occurs. A shortwave trough approaching the coast early Saturday will likely deepen the marine layer enough to push clouds inland up the lower Columbia River Valley into the Portland metro. Afternoon sun should allow temps to warm again into the mid to upper 80s across the interior lowlands.

There is high confidence temperatures trend into the lower to mid 80s Sunday through early next week as a more zonal flow pattern emerges. Still no rainfall chances in the next week as we head into the middle of August. /DH

AVIATION...Through 12Z Fri

Southwest flow aloft as high pressure remains over the region. Satellite imagery reveals marine stratus entrenched along the coast and pushing into the Coast Range valleys as well as up the lower Columbia River into KKLS. Terminal observations depict IFR to low-end MVFR CIGs, which are expected to persist through at least Friday morning. There is around a 70-80% chance that clouds scatter out near KAST after 21z this afternoon, while chances for improved flight conditions near KONP remains low. Inland terminals are expected to remain VFR through the period with lingering haze continuing to clear through the day. Light northwesterly winds increase to around 5-10 kt later this afternoon. Marine stratus is expected to redevelop at the coast by 03z Saturday.

KPDX AND APPROACHES...VFR conditions with clear skies expected through the TAF period. Lingering haze gradually clears out through the day. Light northwest winds increase to around 6-8 kt this afternoon. /DH

MARINE

High pressure offshore will maintain northerly winds through the weekend and into next week. Winds are expected to remain 20 kt or less today through Saturday morning. By Sat afternoon, surface pressure gradients are expected to tighten as an inverted surface thermal trough strengthens over northern California toward the south Oregon coast. This will bring increasing chances for wind gusts up to 25 kt south of Cape Foulweather over the weekend and into early next week. Generally wind driven seas are expected to remain around 4 to 6 ft through the next week. /DH

PQR WATCHES/WARNINGS/ADVISORIES

OR...None. WA...None. PZ...None.