Area Forecast Discussion Issued by NWS Seattle/Tacoma, WA
000
FXUS66 KSEW 150356
AFDSEW
Area Forecast Discussion
National Weather Service Seattle WA
856 PM PDT Thu Mar 14 2024
.SYNOPSIS...High pressure is building across the Pacific
Northwest bringing a period of warmer and drier conditions
through early next week. Here we will see the warmest
temperatures of the year so far. Then, cooler and wetter weather
looks to return around the middle of next week.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY/...Northerly flow aloft as an
upper-level ridge axis sits offshore. A few high clouds are
spilling southward around the northeastern quadrant of the broad
surface high. This, combined with surface flow staying strong
enough should mitigate widespread fog formation tonight.
Otherwise, tonight, dry conditions are to remain along with mostly
clear skies as high pressure continues to build. Overnight lows
will bottom out in the 30s to lower 40s. Best chances for patchy
fog development will be over the river valleys (Snoqualmie,
Chehalis, etc.).
High and dry (and warm) will be the general theme throughout the
short term forecast. The aforementioned upper-level ridge is on
tap to progress eastward on Friday before centering overhead this
weekend. Along with it, a thermally induced surface trough is
forecasted to snake up the coast and promote an offshore
component, aiding in the warm up. Friday we`ll see highs top out
upwards of 10 F above average with values in the lower to upper
60s. Can`t rule out a few spots near 70 F, especially in the
foothills. Then, widespread 70s appear more probable for Saturday
and within the interior on Sunday as temps are forecasted to top
out a whopping 15-18 F above average for mid-March. Gap winds will
also be breezy Friday night into Saturday with gusts up to 25 mph
but below advisory threshold. Overnight lows are to remain
mostly in the 40s during this time.
.LONG TERM /MONDAY THROUGH THURSDAY/...We`ll see cooler weather
reintroduce itself in the long term as offshore flow weakens and
upper-level ridging flattens. Widespread 60s will return on Monday
before highs fall back into the 50s Wednesday-Thursday, around
seasonal norms. Deterministic and ensemble guidance are coming
into agreement in regards to upper-level troughing rebounding
around this time. PoPs will also accompany it as well.
Davis/McMillian
&&
.AVIATION...An upper level ridge building over the region will
maintain north to northeasterly flow aloft through the TAF period.
Surface flow also mostly from the north trough the Puget Sound
terminals and east-northeasterly at HQM. VFR through the TAF
period. Expect a few areas of patchy fog to develop overnight
into Friday, but for the extent of fog to be limited. Most likely
areas to see fog development are areas south of the Sound and
along the Chehalis River valley. Winds persisting from the N/NE at
generally 5-10 kt. Expect a slight uptick in winds to 8-15 kt
Friday morning and afternoon.
KSEA...VFR with high clouds spilling southward overhead.
Northerly winds shifting to the north-northeast by 07Z. A slight
uptick in winds to 8-12 kt expected Friday morning.
Davis/14
&&
.MARINE...High pressure over the northeastern Pacific will
continue to shift inland today. A thermally induced trough of low
pressure will then progress northward along the coast on Friday
into the weekend, maintaining offshore flow across portions of the
region. High pressure will then build back into the northeastern
Pacific early next week. Overall conditions will remain rather
calm across the area waters over the next several days, with
latest guidance still indicative of offshore flow along the Strait
of Juan de Fuca remaining below Small Craft thresholds through
the weekend. Seas look to hover between 6-8 feet into Saturday,
before subsiding to 4-6 feet Sunday. Seas may then briefly tick
back up towards 6-8 feet early next week.
Davis/14
&&
.HYDROLOGY...River flooding is not expected through the next 7
days.
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...None.
&&
$$