textproduct: Portland

SYNOPSIS

Cool onshore flow and persistent cloud cover will maintain below average temperatures over the area through Thursday with little change in the overall weather pattern. Conditions will be mainly dry aside from a few stray sprinkles, mainly over higher terrain. A gradual warming trend develops Friday into the holiday weekend with inland valleys likely warming above 80 degrees by the 4th of July (70-90% chance).

DISCUSSION...Tuesday through Monday night

Conditions today will be very similar to what was observed yesterday as moist onshore flow continues, bringing persistent cloud cover and below average high temperatures mainly in the 60s. Conditions will be mainly dry aside from a few stray sprinkles, mainly over higher terrain. This "wash-rinse-repeat" weather pattern will hold steady on Wednesday as well, resulting in another mostly cloudy day with highs mainly in the 60s to near 70 degrees. There is minimal change to the weather pattern for Thursday too, aside from temperatures aloft warming a few degrees. As a result, temperatures on Thursday are expected to be slightly warmer with highs most likely in the low to mid 70s for most inland valley locations and 60s at the coast. That being said, there is a 5-15% chance inland valleys will stay stuck in the 60s for highs on Thursday, which would occur if skies remain mostly cloudy through the day. Regardless of the outcome, temperatures will still be running a bit below average for early July as average high temperatures for inland valleys are in the upper 70s for July 2.

Confidence increases for a more noticeable warm-up Friday into the upcoming holiday weekend due to the arrival of weak upper level ridging and less cloud cover during peak heating hours. The NBM continues to show a 70-90% chance for highs above 80 degrees by the 4th of July for inland valleys while the coast stays in the 60s. Probabilities for highs above 80 degrees decrease slightly to 60-80% on Sunday and Monday, however highs somewhere in the 80s remains the most likely outcome. One change from yesterday's NBM guidance is a slight lowering of probabilities for highs above 90 degrees. Probabilities for highs above 90 degrees this weekend have lowered to 1-10%, suggesting abnormally hot conditions and heat-related impacts are unlikely to occur. -23

AVIATION

Conditions today will be very similar to what was observed yesterday, with cloudy skies this morning and ceilings hovering around 3500-4000 feet inland, lowering to 2500-3000 feet towards 11-14Z Tuesday. Ceilings should rise back above 4000 feet sometime between 18-22Z Tuesday. The exception is at KAST, where ceilings are expected to hover near 2000 ft throughout the TAF period. Winds are generally light, but will increase out of the northwest late Tuesday afternoon around 5 to 10 kt.

KPDX AND APPROACHES...Cloudy skies are expected through most of the TAF period, with ceilings around 3500-4000 feet lowering to 2500-3000 feet by approximately 14Z Tuesday. Ceilings will most likely rise to around 4000 ft or higher by approximately 18-19Z Tuesday, however the exact timing is uncertain. By 21Z Tuesday, probabilities for ceilings below 3000 ft lower to 15-20% and then fall below 10% beginning at 22Z. -23

MARINE

Northwest winds around 10 to 20 kt with steep seas near 7 to 10 ft at 9 to 10 seconds driven mainly by a northwest swell continue today through early Wednesday. Given steep seas and wind gusts upwards of 20 kt, a Small Craft Advisory remains in effect for both the inner and outer waters through late Wednesday morning, except through early Wednesday morning for the central and southern inner waters. Rough bar conditions are also expected within the main channel of the Columbia River Bar through late Tuesday morning with steep seas around 7 to 9 ft at 9 to 10 seconds and northwest winds around 10 to 15 kt. Conditions over the bar will be particularly steep and choppy between 3-8 AM PDT Tuesday during a strong ebb current. Therefore, a Small Craft Advisory remains in effect for the Columbia River Bar through 11 AM PDT Tuesday.

Winds and seas will ease significantly Wednesday afternoon and evening, with benign conditions expected Thursday and Friday. Seas are expected to range between 4 and 6 ft Wednesday night through the upcoming weekend, with north to northwest winds continuing. Northerly winds do increase in strength over the weekend, especially during the afternoon and evening hours when gusts up to 20-25 kt are expected. -23

PQR WATCHES/WARNINGS/ADVISORIES

OR...None. WA...None. PZ...Small Craft Advisory until 11 AM PDT this morning for PZZ210.

Small Craft Advisory until 11 AM PDT Wednesday for PZZ251- 271>273.

Small Craft Advisory until 2 AM PDT Wednesday for PZZ252-253.