Heavy snow fell over portions of central Washington and Oregon due to a cold front. Snowfall amounts in inches are as followed: (14) recorded at the Milk Shakes Snotel and (10) in 24 hours 5 miles north northwest of La Pine.
Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
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 PDT wrote it up.
Heavy snow fell over portions of central Washington and Oregon due to a cold front. Snowfall amounts in inches are as followed: (14) recorded at the Milk Shakes Snotel and (10) in 24 hours 5 miles north northwest of La Pine.
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 Pendleton, OR wrote its last area forecast discussion before the first event at Dec 21, 4:00 AM PST, 3 hours 45 minutes earlier.
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
400 AM PST MON DEC 21 2015
UPDATED AVIATION DISCUSSION
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT...MOST OF THE PRESSING
CONCERNS ARE TODAY THROUGH THIS EVENING AS A VERY STRONG LOW PRESSURE
SYSTEM MOVES EAST OF THE CASCADES AND ACROSS THE LOWER COLUMBIA
BASIN OF WASHINGTON. THE EFFECTS WILL BE TWOFOLD...HEAVY SNOW AND
HIGH WINDS. THERE ARE NUMEROUS WINTER STORM WARNINGS IN EFFECT IN
OREGON AND WASHINGTON. THE BEST BET FOR HEAVY SNOW WILL BE ALONG THE
WASHINGTON CASCADE EAST SLOPES AND KITTITAS VALLEY WHERE COLD AIR
WILL HANG ON THE LONGEST...AND OVER THE HIGHEST ELEVATIONS OF THE
BLUE MOUNTAINS WHERE FAVORABLE OROGRAPHICS WILL KICK IN THIS
EVENING. HIGH WIND WARNINGS ARE ISSUED FOR A LARGE AREA ALONG AND
SOUTH OF THE LOW TRACK. VERY STRONG LOW-LEVEL WINDS WILL BE IN
PLACE AND THE PATTERN APPEARS QUITE FAVORABLE FOR DAMAGING WINDS.
THE ONLY CONCERN IS THAT SOME OF THE NUMERICAL MODELS ARE NOT
SHOWING ESPECIALLY EFFECTIVE MIXING OF THESE WINDS TO THE GROUND.
THAT BEING SAID THE WINDS JUST OFF THE SURFACE ARE 60 TO 70 KT SO
POCKETS OF DAMAGING WINDS WILL BE POSSIBLE THIS AFTERNOON AND
EVENING. THINGS WILL QUIET DOWN LATER TONIGHT AND EARLY TUESDAY BUT
ANOTHER STORM WILL IMPACT THE AREA MAINLY TUESDAY NIGHT WITH MORE
LOW ELEVATION RAIN/SNOW ABOVE 2000 FEET AND AT LEAST SOME WIND
BUT NOT TO THE EXTENT EXPECTED TODAY. 78
.LONG TERM...WEDNESDAY THROUGH SUNDAY...A VERY PROGRESSIVE FLOW
ALOFT ASSOCIATED WITH A VIGOROUS UPPER LEVEL JET STREAM WILL STEER A
SERIES OF DISTURBANCES ACROSS THE INTERIOR PACIFIC NORTHWEST DURING
THE PERIOD. THE UPPER LEVEL JET BUCKLES UPSTREAM ON WEDNESDAY DUE TO
AN AMPLIFYING MID/UPPER LEVEL TROUGH MOVING SOUTHEAST FROM THE GULF
OF ALASKA WITH THE EASTERN FLANK OF THE TROUGH SENDING ANOTHER WARM
FRONT ACROSS THE FORECAST AREA DURING THE DAY ON WEDNESDAY WITH SNOW
LEVELS OF 1000-2000 FEET.
WEDNESDAY NIGHT THE AMPLIFYING MID/UPPER LEVEL TROUGH CONTINUES
MOVING SOUTHEAST MAKING LANDFALL OVERNIGHT, AND THEN MOVES ACROSS
PACIFIC NORTHWEST ON THURSDAY AND KEEPS SNOW LEVELS AT THE SURFACE
FOR A CHANCE OF SNOW THROUGH THE DAY ON THURSDAY AND ON THURSDAY
NIGHT WITH THE TROUGH EXITING THE REGION OVERNIGHT. THEN ON
CHRISTMAS DAY A DRIER AND COLDER AIRMASS MOVES INTO THE INTERIOR
PACIFIC NORTHWEST FOR DRY CONDITIONS, BUT WITH A CHANCE OF
OROGRAPHIC SNOW SHOWERS IN THE BLUE MOUNTAINS AND IN THE WALLOWA
MOUNTAINS. FRIDAY NIGHT AND SATURDAY A RIDGE OF HIGH PRESSURE BUILDS
OVER US FOR DRY CONDITIONS THROUGH SATURDAY NIGHT WITH A CHANCE OF
PRECIPITATION MOVING EAST OF THE CASCADES ON SUNDAY. POLAN
&&
.AVIATION...12Z TAFS...SNOW OR RAIN WILL DEVELOP ACROSS THE AREA
CAUSING LOW CIGS AND POOR VISIBILITIES, WHICH WILL CAUSE MVFR OR IFR
CONDITIONS AT TIMES. IN ADDITION STRONG WINDS WILL DEVELOP OVER MOST
LOCATIONS TODAY WITH WIND SPEEDS OF UP TO 25 TO 35 KTS WITH GUSTS TO
45 KTS AT TIMES AT TAF SITES, EXCEPT AT KYKM AND KPSC, WHICH WILL
HAVE WIND SPEEDS OF 15 TO 25 KTS WITH GUSTS AT KPSC TO 35 KTS FROM
22ND/00Z-05Z. POLAN
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 44 33 40 33 / 90 40 30 50
ALW 44 34 43 35 / 100 60 30 60
PSC 44 34 43 33 / 90 40 20 50
YKM 38 27 38 28 / 100 40 20 40
HRI 48 35 42 30 / 90 30 20 50
ELN 33 25 35 29 / 100 50 30 50
RDM 43 28 38 30 / 80 30 20 40
LGD 36 29 35 29 / 90 50 30 60
GCD 37 24 31 21 / 90 60 20 60
DLS 46 35 43 33 / 90 40 30 60
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...HIGH WIND WARNING FROM 10 AM THIS MORNING TO 10 PM PST THIS
EVENING FOR ORZ041-044-505-507>511.
WINTER STORM WARNING FROM 6 AM THIS MORNING TO 3 PM PST THIS
AFTERNOON FOR ORZ509.
WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 4 AM PST
TUESDAY FOR ORZ050-503-506.
WINTER STORM WARNING FROM 10 AM THIS MORNING TO 10 AM PST
TUESDAY FOR ORZ502.
WINTER STORM WARNING FROM 6 AM THIS MORNING TO NOON PST TODAY
FOR ORZ041.
WA...HIGH WIND WARNING FROM 10 AM THIS MORNING TO 10 PM PST THIS
EVENING FOR WAZ024-028>030-521.
WINTER STORM WARNING FROM 10 AM THIS MORNING TO 10 AM PST
TUESDAY FOR WAZ030.
WINTER STORM WARNING FROM 6 AM THIS MORNING TO 8 PM PST THIS
EVENING FOR WAZ026-027-521.
WINTER STORM WARNING FROM 6 AM THIS MORNING TO 4 AM PST TUESDAY
FOR WAZ520.
WINTER STORM WARNING FROM 6 AM THIS MORNING TO NOON PST TODAY
FOR WAZ024.
&&
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
78/99/99PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PENDLETON OR
741 AM PST MON DEC 21 2015
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0738 AM SNOW 8 SSW TROUT LAKE 45.89N 121.59W
12/21/2015 M5.5 INCH KLICKITAT WA COCORAHS
24-HOUR ACCUMULATION 5.5 INCHES. 21.5 INCHES OF SNOW ON
THE GROUND.
0738 AM SNOW 4 NW MEACHAM 45.55N 118.48W
12/21/2015 M3.0 INCH UMATILLA OR COCORAHS
24 HOUR ACCUMULATION 3 INCHES
0738 AM SNOW 1 S BEND 44.05N 121.31W
12/21/2015 M4.3 INCH DESCHUTES OR COCORAHS
4.3 INCHES IN 24 HOURS
&&
MWISTERThe national radar mosaic for the moment the first event began.
2 heavy snow. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Oregon in 2015Every state in 2015This day in weather historyWarnings in Oregon, December 2015
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: 606402, 606400.