textproduct: Seattle/Tacoma

SYNOPSIS

Generally dry conditions expected into next week. Warmer temperatures this weekend. Temperatures cool slightly Sunday into Monday with a trough over Western Washington. An upper level ridge will settle over the region midweek.

SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/

Still plenty of cloud cover this afternoon across Western Washington. Clouds are expected to slowly scatter out late this afternoon/evening. An upper level ridge edging into British Columbia and an upper level low to the east will maintain dry northerly flow aloft into the weekend. Temperatures today will peak in the mid 50s to low 60s. Lows in the upper 30s to low 40s tonight. Plenty of sunshine Friday and Saturday and warmer temperatures. High temperatures Friday will be in the upper 50s to mid 60s. As for Saturday, high temperatures will be in the 60s to low 70s.

Breezy northeasterly winds on Friday with gusts generally around 20- 25 mph. Stronger gusts expected along the coast and San Juan Islands, up to 30 mph. Winds will gradually subside into the evening hours. Friday night into Saturday morning will also be on the cool side with the potential for frost development, with current probabilities around 30-50% of seeing temperatures below 37 degrees.

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LONG TERM /SUNDAY THROUGH THURSDAY/

Another cool night expected Saturday night into Sunday morning with the potential for frost. Models are trending slightly warmer than the day before, but there is still a slight chance (25-40%) for temperatures below 37 degrees for the southern interior.

Ensemble guidance remains in good agreement with an upper level low to the east digging back to the west into Western Washington Sunday and Monday. Conditions still trending dry for the majority of places. However, increased cloud cover and light precipitation is possible for the Cascades. The upper level low will push east on Tuesday allowing an upper level ridge offshore to settle over Western Washington starting late Tuesday. This ridge will bring bring warmer conditions to the area. Models are suggesting temperatures will warm up into the mid 60s along the coast and upper 60s to low 70s along the interior Wednesday and Thursday.

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AVIATION

An upper low/trough will continue to dig east of the terminals, with increasing north flow aloft tonight into Friday. Cloud coverage remains well intact this afternoon, with satellite showing some scattering beginning to take place to the north in Whatcom/Skagit Counties. The lowest ceilings this afternoon remain in the north sound with MVFR conditions, which will lift to VFR later this afternoon. VFR conditions continue elsewhere, with partial to near total clearing expected to continue southward this afternoon & evening. Winds this afternoon will turn from southwest to northwest 4-8 kt as the north flow mixes down. Fog likelihood for Friday morning is low as the winds turn to the northeast and dry the air, but can't rule out a few patches of fog or low cigs in the morning (best chance is for Cascades and Pacific Coast areas). Clear skies are expected for Friday. Few spots Friday may see northeast gusts to 20 kt in the morning/afternoon.

KSEA...VFR expected through the TAF period. Ceilings this afternoon will lift and scatter this evening. Probabilities for fog remain very low, but could see a few CIGs develop in the morning. Southwest winds 4-8 kt will shift to the northwest this evening after 23Z, continuing to the northeast tonight/Friday. Winds may become gusty to 20 kt from the north/northeast Friday.

HPR

MARINE

A trough to the east will move inland on Friday, with onshore flow beginning to weaken and becoming offshore with broad high pressure in the northeast Pacific. A few spots Friday have a medium chance of seeing breezy northeast gusts over 20 kt (the north interior waters, Strait of Juan de Fuca, and adjacent coastal waters). Outside of this, the pattern remains quiet with occasional diurnal pushes through the strait next week as the flow returns to onshore. Dry conditions are expected over the waters most of the forecast period, with a slight chance of showers Monday. A couple spots may see patchy fog Friday morning.

Seas 6-8 ft Thursday will decrease to 4-6 ft Friday-Saturday, building back to 6-8 ft Sunday-Monday before decreasing back to 4-6 ft.

HPR

HYDROLOGY

No river flooding expected in the next 7 days.

SEW WATCHES/WARNINGS/ADVISORIES

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