Heavy rains from a slow moving, moist front brought heavy rains to portions of southwest Washington and northwest Oregon. The focus of the heavy rain was to the south Washington and north Oregon coast and coastal mountains where 30 hour rain totals ranged from 3 to 5 inches.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS PQR wrote it up.
Heavy rains from a slow moving, moist front brought heavy rains to portions of southwest Washington and northwest Oregon. The focus of the heavy rain was to the south Washington and north Oregon coast and coastal mountains where 30 hour rain totals ranged from 3 to 5 inches. In addition to the rain, high winds developed as well.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Portland, OR wrote its last area forecast discussion before the first event at Feb 28, 10:04 AM PST, 4 hours 31 minutes earlier.
Area Forecast Discussion...Updated
National Weather Service Portland OR
1004 AM PST Wed Feb 28 2024
.SYNOPSIS...An active and unsettled weather pattern continues
the rest of the week through the weekend with the primary
impacts focused on mountain snowfall tonight onward in addition
to a period of widespread breezy conditions this afternoon and
overnight. A Winter Storm Warning remains in effect for the
Cascades and foothill locations above 1500ft and a Winter
Weather Advisory is in effect for the Oregon Coast range above
1500ft as well - if you have plans to travel across our mountain
passes the second half of this week through the weekend make
sure you’re prepared for winter driving conditions! Otherwise,
we’ll see a cooler and showery airmass stick around into the
weekend with wet snowfall or rain/snow mix chances(25-45%)
sneaking back towards the lowest inland elevations during the
overnight hours. For now though, it appears any appreciable
snowfall impacts other than a skiff of snow on grassy surfaces
will likely hold above 1000ft.
&&
.SHORT TERM...TODAY THROUGH FRIDAY...This morning a warm-front
courtesy of a strong upper-level trough in the Gulf of Alaska
will continue to keep precipitation and warmer air aloft
streaming into the region as the day goes on. Looking at
surface observations, temperatures have generally increased as
the past night with yesterday’s(Tuesday) high temperature
actually occurring just before midnight. As a result of this
persistent warming both at the surface and aloft, snow-levels
will continue rise, peaking around 4500-5500ft during the
afternoon hours. We continue to monitor river levels as rainfall
now precipitating on recent snowfall from earlier this week
will be moderate over the coast range, Willapa Hills, and
Cascades, aided by IVT values of 250-500kg/m/s and an
intensifying low level jet which will supporting good orographic
precipitation enhancement. Still, confidence is moderate to
high(70-80%) local rivers remain below minor flood stage
although several river like the Tualatin, Marys, North Santiam,
and Luckiamute experience sharp rises near to above
bankfull/action stage. It’s also worth noting isolated urban
and small creek/stream flooding can’t be ruled out over the
coast range and Willapa hills today where rainfall rates will be
the highest.
Late today into Thursday morning our attention quickly shifts
to the arrival of a strong cold-frontal boundary tapped into a
long swath of pacific moisture dropping into the region from the
northwest. Outside of further increasing precipitation, a
period of breezy to windy conditions are anticipated this afternoon
and evening. The previously mentioned low level jet just ahead
of this frontal feature highlighted by 50-65 knot winds at 850mb
according to the deterministic GFS/NAM/ECMWF aid in facilitating
35 to 45 mph wind gusts at the surface with locally higher
gusts expected for ridge-tops and exposed beached/headlands.
The NBM and HREF continue to show high probabilities(70-95%) for
gusts out of the S-SW to meet or exceed 40mph across the coast,
central/northern Willamette Valley into the Portland/Vancouver
metro area, and higher terrain features. Still, there is a lack
of confidence as to whether gusts exceeding 45mph will be
prolific enough to warrant a Wind Advisory for portions of the
Willamette Valley and Portland/Vancouver metro. Given the
frontal dynamics and lack of a pronounced inversion at the
surface to prevent significant vertical momentum transfer as the
cold front arrives we’ll need to keep watching the potential
for higher gusts(45-50mph+) closely - it’s not out of the realm
of possibility(less than ~10-20% chance) the 40-55 knot winds
just above the surface at 925mb mix towards the ground this
evening for a brief period of time leading to a couple localized
stronger gusts into the Portland/Vancouver metro. Once the
frontal boundary passes, winds return closer to normal by the
daytime hours Thursday.
However, the most significant impact from this cold-frontal
passage tonight through Thursday and Thursday night will
rapidly falling snow levels to 1500-2000ft and the return of
moderate to heavy mountain snowfall leading to degraded travel
conditions.Come early Thursday morning through Friday morning once
these lower snow levels are firmly in place, 24 hour NBM
probabilities to meet or exceed 1 foot of snow sit at 70-95%
for the Cascades into the higher reaches of the Cascade
foothills with a 60-80% chance to meet/exceed 18 inches through
this same 24hr period east Marion County southward - the latest
deterministic snowfall forecast calls for roughly 18-21 inches
for both Santiam and Willamette Pass. As such, a Winter Storm
Warning remains in effect for the Oregon and Washington Cascades
and adjacent foothills. The coast range likely receives some
snowfall as well although the greatest impacts will stay above
the passes on US-20, US-26, etc so the Winter Storm Watch has
been converted to a Winter Weather Advisory. On Friday, the
region continues to sit in a cooler and showery post-frontal
regime with snow-levels staying around 1000-1500ft, snowfall
impacts for the aforementioned locations persist. Stronger
convection due to the cold pool aloft Thursday afternoon through
Friday has the potential to produce a rumble of thunder or two
and small hail/graupel so a slight chance(15-25%) for thunderstorms
in the forecast was maintained generally near the coast range
westward where instability is greatest. -Schuldt
.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY NIGHT...Typical late
February weather expected, with showers and cool than normal
temperatures expected through at least the weekend.
Deterministic and ensemble models are persistent with linger
trough over the Pac NW into early next week. Snow levels stay
down, generally in the 800 to 1500 ft range. If downdrafts in
the showers are strong enough, like earlier this week, could
even see some snowflakes survive down to the valley floor, but
little if any accumulation would be expected. The latest NBM
shows a 20-45% probability for trace amounts of snow across the
Valley during the overnight/early morning hours, though there is
less than a 5-10% probability of 1 inch or more. That said, any
spot in such prime condition could get a quick inch or two, but
that is way more likely for the higher hills and Coast
Range/Willapa Hills into the Cascades. The latter location will
look to get another 1 to 2 feet of snow through Sunday above
2000-2500ft. Showers decrease early next week as air mass begins
to moderate slowly. Overall trend for next week appears to be a
very slow return to more typical weather of 1st of March, with
showers at times.
-Rockey/Schuldt
&&
.AVIATION...Moist, southwesterly flow aloft will persist through
Thrusday. A frontal system will continue to spread rain across the
area through tonight. Expect predominately MVFR conditions through
the period, but it will be possible to see periods of IFR at the
coast (40-60% chance) and VFR inland, especially for the southern
Willamette Valley (~50% chance). Southerly winds will also increase
through today. Gusts Wednesday morning will be around 25-35 kts
along the coast and up to 30 kts inland. Wind gusts around 35-45 kts
along the coast and up to 30-40 kts will be possible today. Winds
will decrease quickly from north to south after a strong surface
front passes from 03-09z Thursday.
*NOTE: The observation out of KONP is generally limited to wind
and pressure at this time. Periodically cloud cover, vis, and
present wx are reported but are unreliable.
PDX AND APPROACHES... Predominately MVFR conditions with steady
rain. CIGS expected to gradually lower today. South-southwest winds
around 12-16 kt with gusts 20-25 kt, gusts increasing to peak around
30-35 kts 18z today through 09z Thursday.
-HEC/Batz
&&
.MARINE...An active weather pattern continues through this week
as a very large scale Alaskan low brings multiple fronts across
the coastal waters through the weekend. Winds and seas continue
to increase this morning into this afternoon as a gale force cold
front approaches. Widespread Gales are expected across all waters
with gusts up to 45 kt. Winds will rapidly decrease behind the
front tonight through early Thursday morning. A Gale Warning
remains in effect through late tonight for all waters. Seas around
9-12 feet this morning will build towards 14 to 16 ft this
afternoon into Thursday morning. Seas will briefly decrease back
to the low teens before beginning to build again Thursday
afternoon with a period of 12-14 seconds. Therefore, a Hazardous
Seas Watch has been issued for all waters from the expiration of
the Gale Warning through Tuesday afternoon.
Another weak front will move over the waters late Thursday,
causing winds to increase again accompanied by a more robust,
westerly swell that will cause seas to build towards 17 to 19 ft
by Friday. -HEC
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...Winter Weather Advisory from 10 PM this evening to 6 AM PST
Friday for Central Coast Range of Western Oregon-Coast
Range of Northwest Oregon.
Winter Storm Warning from 4 PM this afternoon to 6 AM PST Friday
for Cascade Foothills in Lane County-Cascades in Lane
County-Northern Oregon Cascade Foothills-Northern Oregon
Cascades-Upper Hood River Valley.
WA...Winter Storm Warning until 6 AM PST Friday for South Washington
Cascade Foothills-South Washington Cascades.
PZ...Gale Warning until 11 PM PST this evening for Coastal waters
from Cape Shoalwater WA to Cape Falcon OR out 10 NM-
Columbia River Bar-Waters from Cape Shoalwater WA to Cape
Falcon OR from 10 to 60 NM.
Hazardous Seas Watch from this evening through Thursday
afternoon for Coastal waters from Cape Shoalwater WA to
Cape Falcon OR out 10 NM-Columbia River Bar-Waters from
Cape Shoalwater WA to Cape Falcon OR from 10 to 60 NM.
Gale Warning until 2 AM PST Thursday for Coastal waters from
Cape Foulweather OR to Florence OR out 10 NM.Coastal waters
from Cape Foulweather OR to Florence OR from 10 to 60 NM.
Hazardous Seas Watch from late tonight through Thursday
afternoon for Coastal waters from Cape Foulweather OR to
Florence OR out 10 NM.Coastal waters from Cape Foulweather
OR to Florence OR from 10 to 60 NM.
&&
&&
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National Weather Service Portland OR
1109 AM PST Wed Feb 28 2024
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1030 AM Rain 4 ENE Cathlamet 46.22N 123.30W
02/28/2024 M1.70 inch Wahkiakum WA Trained Spotter
Measured 24 hour rainfall.
&&
ACBPreliminary Local Storm Report
National Weather Service Portland OR
200 PM PST Wed Feb 28 2024
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0159 PM Rain 4 ENE Cannon Beach 45.90N 123.87W
02/28/2024 M2.07 inch Clatsop OR Trained Spotter
Rainfall since midnight PST.
&&
Weagle1 high wind. Local standard time, as filed.
Peak winds to 60 mph reported at Clatsop Spit and Megler Bridge on highway 101.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Oregon in 2024Every state in 2024This day in weather historyWarnings in Oregon, February 2024
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1164386.