Climatological Report (Annual) Issued by NWS Portland, OR
000
CXUS56 KPQR 011952
CLAPDX
ANNUAL CLIMATE REPORT
NATIONAL WEATHER SERVICE PORTLAND OR
1152 AM PST FRI JAN 1 2021
...PORTLAND 2020 WEATHER IN REVIEW...
=================================================================
2020 NOTABLE RECORDS... 2020 NOTABLE WEATHER EVENTS...
*** 2ND WARMEST JANUARY *** HEAVY WET SNOW (MID-MARCH)
*** 8TH DRIEST FEBRUARY *** DAMASCUS TORNADO (13 JUNE)
*** 4TH DRIEST APRIL *** SEPTEMBER WILDFIRES AND SMOKE
*** 5TH WARMEST APRIL *** MID-SEPTEMBER THUNDERSTORMS
*** 5TH WETTEST JUNE *** ST HELENS TORNADO (10 NOV)
*** 3RD WARMEST SEPTEMBER
*** 9TH WARMEST DECEMBER
MONTHLY WEATHER SUMMARIES...
JANUARY...2020 STARTED ON A MILD AND WET NOTE. NORMALLY, PORTLAND
WOULD SEE 8 NIGHTS AT/OR BELOW FREEZING. BUT, ONLY IN 3 THIS
YEAR (14TH TO 16TH). DURING THAT TIME, THERE WAS LIGHT SNOW
IN/AND AROUND THE METRO AREA, WITH AN INCH BEING THE MOST.
RAIN FELL ON ALL BUT 2 DAYS THIS JANUARY, THE MOST SINCE IN
JANUARY SINCE 1964 (NORMAL IS 18 DAYS)
IT WAS THE 2ND WARMEST JANUARY SINCE 1941 (WARMEST IS 1953).
FEBRUARY...A STRONG FRONT PUSHED ACROSS REGION TO START THE MONTH,
WITH RAIN AND WINDS GUSTING TO 40 MPH. ANOTHER ROUND OF WIND
ARRIVED WITH ANOTHER FRONT ON THE 23RD, WITH WINDS GUSTING TO
45 MPH. OTHERWISE, RATHER BENIGN FEBRUARY. TEMPERATURES WERE
NEAR AVERAGE FOR FEBRUARYS, BUT ONLY GOT ABOUT HALF THE RAIN
NORMALLY EXPECTED FOR FEBRUARY.
MARCH...THE BEST WORD TO DESCRIBE MARCH 2020 IS... ROLLERCOASTER.
IT STARTED WET AND MILD. THEN CAME A COOLER PATTERN AS A
COLD UPPER LOW SHIFTED OVER THE PACIFIC NW BY MID-MONTH.
THIS BROUGHT HIGHS ONLY IN THE UPPER 30S TO LOWER 40S, WITH
SNOW ON THE 14TH. MOST AREAS AROUND THE PORTLAND/VANCOUVER
METRO RECEIVED 1 TO 4 INCHES OF SNOW, THE HEAVIER SNOWFALL
ACCUMULATIONS BEING ACROSS CLARK COUNTY AND EAST PORTLAND
METRO, AND TOWARDS THE COLUMBIA RIVER GORGE. BUT, THIS WAS
HEAVY WET SNOW, WHICH RESULTED IN NUMEROUS BROKEN BRANCHES.
A FEW DAYS LATER, THE SNOW WAS JUST A MEMORY, AS AFTERNOON
TEMPERATURES ROSE WELL INTO THE 60S, WITH WARMEST ON 20TH.
APRIL...STARTED WET AND NORMAL, THEN TURNED DRY AND MILD ON 6TH,
LASTING THROUGH THE 17TH, WITH HIGHS IN THE 60S AND 70S.
TEMPERATURES ENDED WELL ABOVE NORMAL, TYING 1990 AS THE 5TH
WARMEST APRIL. BUT, IT WAS A RATHER DRY MONTH, WITH ONLY
0.79 INCH OF RAIN (DOWN 1.94 FROM NORMAL). APRIL 2020 ENDED
AS THE 4TH DRIEST APRIL, AND 5TH WARMEST.
MAY...LIKE 2019, MAY WAS A MONTH FOR GARDENERS. MAY 2020 STARTED
MILD AND SOMEWHAT WET. BUT, BY THE 4TH, TEMPERATURES WERE
IN THE 70S, AND MIDDLE TO UPPER 80S FOR MOTHERS DAY WEEKEND.
THEN, BACK TO RAIN AND TYPICAL SPRING WEATHER FOR MID-MONTH.
THEN ANOTHER WARM SPELL FOR THE 26TH TO 29TH, WITH HIGH IN
THE LOWER 90S ON THE 28TH. FOR MAY 2020, TEMPERATURES WERE
BIT ABOVE NORMAL WHILE RAINFALL WAS ONLY SLIGHTLY BELOW.
JUNE...SPEAKING OF TRANSITION MONTHS, JUNE WAS THAT, WITH COOL
DAMP WEATHER FOR THE FIRST HALF, THEN DRY AND WARM FOR THE
SECOND HALF. STRONG SHOWERS ON THE 7TH PRODUCED A FUNNEL CLOUD
TO NORTH OF MT SCOTT. MOST ACTIVE DAY WAS THE 13TH, A TORNADO
TOUCHED DOWN NEAR DAMASCUS, WITH A DAMAGE PATH OF ABOUT TWO
MILES. RAINFALL IN JUNE WAS 3.51 INCHES, MAKING JUNE 2020
THE 5TH WETTEST JUNE. BUT, AFTER THE 17TH, WEATHER WAS MORE
EARLY SUMMER LIKE, WITH LITTLE IF ANY RAIN AND TEMPERATURES
GETTING BACK INTO THE 70S AND 80S.
JULY...THIS WAS A RATHER WARM JULY, THOUGH DID HAVE RELIEF AS THE
OVERNIGHT LOWS FELL BACK TO THE 50S AND LOWER 60S. TOTAL
RAINFALL WAS 0.05 INCH, WHICH FELL ON ONLY 2 DAYS, THE 1ST
AND 7TH. MOST OF THE MONTH WAS RATHER PLEASANT, WITH HIGHS
IN UPPER 70S TO UPPER 80S. BUT, IT DID GET TOASTY TOWARDS
THE END, WITH 100 DEG ON 26TH AND 27TH.
AUGUST...LIKE JULY, AUGUST STAY ON THE WARM SIDE. AND AGAIN, DID
NOT HAVE ALL THAT MANY HOT DAYS, AS MOST DAILY HIGHS WERE IN
THE 80S. THE WARMEST SPELL WAS 15TH TO 17TH, AS TEMPERATURES
WERE IN THE MIDDLE TO UPPER 90S. BUT, LIKE JULY, TOTAL
RAINFALL WAS ABOUT HALF OF NORMAL, WITH ONLY 0.38 INCH.
SEPTEMBER...THE MONTH STARTED WARM AND DRY. A ABNORMALLY STRONG
STRONG UPPER LOW DROPPED SOUTH INTO THE ROCKIES ON LABOR
DAY WEEKEND, WITH SNOW IN NORTHERN AND CENTRAL ROCKIES.
STRONG HIGH PRESSURE FOLLOWED THAT LOW, AND BROUGHT STRONG
DRY OFFSHORE FLOW TO THE PACIFIC NW. EAST TO NORTHEAST WINDS
OF 30 TO 40 MPH, WITH GUSTS 50 TO 55 MPH WERE FELT ACROSS
THE PORTLAND METRO ON THE 7TH AND 8TH. THESE WINDS WERE
THE STRONGEST WINDS FOR THE MONTH OF SEPTEMBER TO HIT THE
METRO AREA SINCE SEPT 1963. WINDS BROKE TREE BRANCHES,
DOWNED TREES AND POWERLINES, WITH WIDESPREAD POWER OUTAGES
THE AIR WAS QUITE DRY, WITH MINIMUM HUMIDITY NEAR 10%.
BUT, WITH WINDS WERE MUCH STRONGER OVER THE CASCADES. THAT
DOWNED POWERLINES, WITH FIRE ERUPTING WITH THE VERY DRY
CONDITIONS. THESE FIRES BURNED INTENSELY, WITH LARGE
AMOUNTS OF SMOKE LOFTED AND SPREADING OVER MUCH OF THE
REGION. AIR QUALITY PLUMMETED, WITH SMOKE COVER SKIES FROM
THE 7TH THROUGH THE 18TH. THIS SMOKE KEPT DAY TEMPERATURES
DOWN, AND OVERNIGHT LOWS MILD. WORST YET WAS THE MANY DAYS
OF POOR TO EXTREMELY UNHEALTHY AIR QUALITY.
STRONG THUNDERSTORMS ROLLED NORTHWARD ACROSS NORTHWEST
OREGON ON THE 17TH INTO THE 18TH. MOST AREAS RECEIVED 0.50
TO 1 INCH OF RAIN, THOUGH DID SEE SPOTS WITH 1 TO 2 INCHES
IN PARTS OF EAST VANCOUVER AND GRESHAM.
AFTERWARDS, WEATHER PATTERN CHANGED, WITH MORE ONSHORE FLOW
AND SOUTHWEST FLOW ALOFT. THIS ALLOWED SMOKE TO BE SHUNTED
BACK TO THE EAST, WITH IMPROVED AIR QUALITY. A STRONG FRONT
ARRIVED ON THE 23RD, BRINGING 1 TO 2 INCHES OF RAIN.
SEPTEMBER 2020 MEAN TEMPERATURE OF 67.4 DEG TIES WITH 2011
AND 1991 AS THE 3RD WARMEST SEPTEMBER ON (WARMEST ON RECORD
IS 67.6 DEG BACK IN SEP 2014 AND SEP 1994)
OCTOBER...AFTER A MILD AND DRY START, THE TRANSITION FROM LATE
SUMMER-LIKE WEATHER TO AUTUMN BEGAN IN EARNEST BY THE 10TH.
SERIES OF FRONTS ARRIVED, WITH RAIN ON JUST ABOUT EVERY DAY
FROM 9TH TO 24TH. BUT, THE RAINFALL WAS NOT ALL THAT HEAVY.
INTERESTINGLY, THE RAINFALL FROM 15TH TO THE 31ST WAS NOT
MUCH, WITH A TOTAL OF 0.08 INCH FALLING DURING THAT TIME.
CHILLY AIR SETTLED OVER REGION LATER IN THE MONTH, WITH
AUTUMN`S FIRST FREEZE ON 26TH. THE LAST TIME TEMPERATURES
DROPPED THIS COLD THIS EARLY IN THE SEASON WAS THE 19TH
OF OCTOBER 1949, WHEN THE TEMPERATURES DIPPED TO 27 DEG.
NOVEMBER...NOVEMBER 2020 WAS ABOUT AS CLOSE TO NORMAL AS WOULD
EXPECT FOR A NOVEMBER. MOST ACTIVE WEATHER DAY WAS ON THE
10TH, AS LOCAL AREA SAW SHOWERS AND A FEW THUNDERSTORMS.
ONE THUNDERSTORM PRODUCED A TORNADO ON THE NORTHWEST SIDE
OF ST HELENS.
DECEMBER...DECEMBER STARTED ON A DRY NOTE. BUT, THEN THE RAIN
RETURNED, WITH RAIN EVERY DAY FROM THE 8TH THROUGH THE 22ND.
AN ATMOSPHERIC RIVER PUSHED OVER THE REGION LATE ON THE 19TH
AND 20TH, WITH HEAVY RAIN. DURING THAT TIME, MANY AREAS IN
AND AROUND THE PORTLAND/VANCOUVER METRO AREA RECEIVED 1.75
TO 3.00 INCHES OF RAIN. THIS PUSHED MANY SMALL STREAMS OUT
OF THEIR BANKS, WITH SOME MINOR FLOODING ALONG THE PUDDING
RIVER. A LANDSLIDE ON THE 20TH, CLOSING THE COLUMBIA GORGE
HISTORIC HIGHWAY FOR A TIME. ANOTHER TROUBLE SPOT WAS ON
HIGHWAY 99E, NEAR CANEMAH BLUFFS WHERE A LARGE BOULDER BROKE
LOOSE AND FELL ONTO THE HIGHWAY. REST OF THE MONTH WAS MILD.
ON A SIDE NOTE: THE COLDEST TEMPERATURE FOR THE MONTH WAS
27 DEG ON THE 29TH, WHICH WAS ALSO THE COLDEST FOR THE
ENTIRE YEAR OF 2020. THE WARMEST EXTREME LOW FOR A YEAR WAS
WAS 27 DEG BACK IN 1953 AND 1992, AND NOW 2020.
==============================================================
NEW RECORDS SET IN 2020 (PREVIOUS RECORD IN PARENTHESES)
+ INDICATES MOST RECENT OF MULTIPLE OCCURRENCES
JANUARY...
3RD NEW. DAILY WARM HIGH TEMP 62 ( 60 /1989 )
31ST NEW. DAILY WARM HIGH TEMP 62 ( 61 /1995 )
*** 2ND WARMEST JANUARY ON RECORD (AVERAGE TEMP 45.8 DEG)
FEBRUARY...
6TH TIED. DAILY WARM HIGH TEMP 59 ( 59 /1998 )
*** 8TH DRIEST FEBRUARY ON RECORD (TOTAL RAINFALL 1.55")
MARCH....
14TH NEW. DAILY COOL HIGH TEMP 42 ( 43 /2012+)
APRIL...
*** 4TH DRIEST APRIL ON RECORD (TOTAL RAINFALL 0.79 INCH)
*** 5TH WARMEST APRIL ON RECORD (AVERAGE TEMP 45.8 DEG)
MAY...
9TH NEW. DAILY WARM LOW TEMP 59 ( 56 /1987 )
9TH NEW. DAILY W0ARM HIGH TEMP 87 ( 86 /1987 ) 10TH
NEW. DAILY WARM LOW TEMP 59 ( 54 /1960+)
JUNE...
10TH NEW. DAILY WARM LOW TEMP 60 ( 59 /2009 )
11TH TIED. DAILY WARM LOW TEMP 60 ( 60 /1969 )
*** 5TH WETTEST JUNE ON RECORD (TOTAL RAINFALL 3.51 INCHES)
JULY...
26TH NEW. DAILY WARM HIGH TEMX.XP 100 ( 99 /1998 )
AUGUST...
16TH TIED. DAILY WARM LOW TEMP 68 ( 68 /2008 )
SEPTEMBER...
3RD TIED. DAILY WARM HIGH TEMP 95 ( 95 /2017 )
8TH TIED. DAILY WARM LOW TEMP 65 ( 65 /2017 )
9TH NEW. DAILY WARM LOW TEMP 65 ( 63 /2017 )
22ND TIED. DAILY WARM LOW TEMP 61 ( 61 /2014 )
23RD TIED. DAILY WARM LOW TEMP 60 ( 60 /2014 )
*** 3RD WARMEST SEPTEMBER (TIES 2011 AND 1991 AS 3RD PLACE)
OCTOBER...
8TH NEW. DAILY WARM LOW TEMP 58 ( 57 /2016+)
26TH NEW. DAILY COLD LOW TEMP 29 ( 30 /1963 )
27TH TIED. DAILY COLD LOW TEMP 31 ( 31 /1970+)
NOVEMBER...
NO NEW RECORDS SET.
DECEMBER...
19TH NEW. DAILY WARM LOW TEMP 49 ( 48 /2018 )
20TH NEW. DAILY RAINFALL 1.43" (1.28"/1961 )
21ST TIED. DAILY WARM HIGH TEMP 62 ( 62 /1940+)
*** 9TH WARMEST DECEMBER (TIED WITH 1957 AND 1999 AS 9TH)
==============================================================
2020 PORTLAND MONTHLY TEMPERATURE AND PRECIPITATION RANKINGS
THIS SHOWS WHERE MONTH/YEAR RANKS IN PORTLANDS CLIMATE RECORD
(OCT 1940 THROUGH 2020). RANKINGS APPLY TO ALL OF SAME MONTH,
OR IN OTHER WORDS, WHERE JAN 2020 COMPARES TO ALL OTHER JAN.
RANKINGS ARE 1 TO 80, WHERE 1 IS WARMEST OR WETTEST ON RECORD
AND 80 IS DRIEST OR COLDEST ON RECORD.
X.X
JA FE MA AP MA JU JL AU SE OC NO DE 2020
AVG T 2 29 44 5 13 28 21 16 3 16 40 9 6
PRECIP 15 73 65 77 37 5 66 45 23 66 41 43 57
MAX T 7 25 45 7 25 39 28 16 24 20 38 6 9
MIN T 2 41 49 17 9 15 15 16 1 14 39 13 7
=============================================================
2020 PORTLAND AIRPORT TEMPERATURE DATA
+ BY DATE INDICATES LAST OF SEVERAL OCCURRENCES LISTED
|--- AVERAGES ----| MEAN T DEPART| EXTREME TEMPS & DATE|
MONTH |HIGHS LOWS MEAN| FROM NORMAL | HIGHEST LOWEST |
--------------------------------------------------------------
JAN 50.2 41.4 45.8 +4.4 DEG 62 /31ST 30 /17TH
FEB 51.9 36.0 43.9 +0.1 DEG 62 /27TH 28 / 4TH
MAR 54.6 38.2 46.4 -1.8 DEG 67 /20TH 30 /17TH
APR 64.9 44.1 54.5 +2.2 DEG 76 /17TH 36 /13TH
MAY 69.7 51.0 60.4 +2.1 DEG 91 /28TH 38 / 4TH
JUN 73.3 55.1 64.2 +0.6 DEG 93 /23RD 49 / 7TH+
JUL 81.5 58.9 70.2 +1.0 DEG 100 /27TH+ 54 /13TH
AUG 83.1 59.2 71.1 +1.6 DEG 99 /15TH 51 /30TH
SEP 77.3 57.5 67.4 +2.9 DEG 95 / 3RD 51 /27TH+
OCT 65.0 47.3 56.2 +1.3 DEG 81 / 2ND 29 /26TH
NOV 52.8 40.0 46.4 -0.2 DEG 68 / 4TH 30 / 9TH
DEC 49.5 38.3 43.9 +3.5 DEG 62 /21ST 27 /29TH
2020 64.5 47.2 55.8 +1.3 DEG 100 /JUL 27+ 28 /FEB 4
NORMAL 63.2 45.7 54.5
DAYS IN 2020 WITH TEMPERATURE OF...
|------ MAXIMUM TEMP --------||------ MINIMUM TEMP ---|
<=32 60+ 70+ 80+ 90+ 100+ <=20 <=32 60+ 70+
--------------------------------------------------------------
JAN 0 2 0 0 0 0 0 3 0 0
FEB 0 1 0 0 0 0 0 8 0 0
MAR 0 8 0 0 0 0 0 5 0 0
APR 0 25 10 0 0 0 0 0 0 0
MAY 0 27 14 6 1 0 0 0 0 0
JUN 0 30 20 6 1 0 0 0 6 0
JUL 0 31 28 17 6 2 0 0 13 0
AUG 0 31 31 21 4 0 0 0 14 0
SEP 0 30 24 12 3 0 0 0 12 0
OCT 0 25 7 1 0 0 0 2 0 0
NOV 0 5 0 0 0 0 0 3 1 0
DEC 0 1 0 0 0 0 0 6 0 0
2020 0 216 134 63 15 2 0 27 46 0
NORMAL 2 197 120 54 12 1 2 30 21 0
FIRST/LAST OCCURRENCES OF... IN 2020 AVERAGE
LAST 32 DEG OR COLDER IN SPRING 17 MAR (19 MAR)
FIRST 70+ DEG OF THE YEAR 8 APR (30 MAR)
FIRST 80+ DEG OF THE YEAR 8 MAY (10 MAY)
FIRST 90+ DEG OF THE YEAR 28 MAY (16 JUN)
LAST 90+ DEG OF THE YEAR 7 SEP ( 8 SEP)
LAST 80+ DEG OF THE YEAR 2 OCT (29 SEP)
LAST 70+ DEG OF THE YEAR 9 OCT (18 OCT)
FIRST 32 DEG OR COLDER IN FALL 26 OCT (15 NOV)
==============================================================
2020 PORTLAND AIRPORT RAINFALL DATA...
TOTAL DEPARTURE DAYS WITH AT LEAST... GREATEST IN
MONTH RAIN FM NORMAL 0.01 0.10 0.50 1.00 24HRS & DATE
---------------------------------------------------------------
JAN 7.58 +2.70 27 24 3 0 1.26 JAN 27-28
FEB 1.55 -2.11 13 5 1 0 0.54 FEB 15-16
MAR 2.43 -1.25 13 7 1 0 0.81 MAR 13-14
APR 0.79 -1.94 12 2 0 0 0.25 APR 22
MAY 2.21 -0.26 17 9 0 0 0.36 MAY 14-15
JUN 3.51 +1.81 14 9 1 1 1.35 JUN 5-6
JUL 0.05 -0.60 2 0 0 0 0.03 JUL 7
AUG 0.38 -0.29 3 2 1 0 0.19 AUG 6
SEP 2.06 +0.59 4 3 2 0 0.88 SEP 25
OCT 1.51 -1.49 9 3 1 0 0.83 OCT 9-10
NOV 5.28 -0.35 20 14 4 0 0.98 NOV 12-13
DEC 5.09 -0.40 20 11 2 1 1.64 DEC 19-20
2020 32.44 -3.59 154 89 15 2 1.64 DEC 19-20
NORMAL 36.03 155 91 19 4
TOTAL SNOWFALL... 0.5 INCH (NORMAL 4.3 INCHES)
PORTLAND WATER YEAR 2019-20 (1 OCT 2019 THROUGH 30 SEP 2020)
27.98 INCHES 8.05 INCHES BELOW NORMAL
============================================================
2020 PORTLAND AIRPORT WIND AND PRESSURE DATA...
AVERAGE SPEED (MPH) STRONGEST WIND GUST
2020 (NORMAL) DIRECTION SPEED DATE
---------------------------------X.X--------------------------
JAN 10.5 (9.3) EAST 42 MPH JAN 15
FEB 5.6 (8.7) SOUTHWEST 44 MPH FEB 23
MAR 6.7 (7.7) EAST 42 MPH MAR 8
APR 5.6 (7.1) EAST 32 MPH APR 16
MAY 6.7 (6.7) EAST 36 MPH MAY 8
JUN 6.3 (7.0) NORTHWEST 26 MPH JUN 28+
JUL 6.3 (7.2) NORTHWEST 28 MPH JUL 18
AUG 6.5 (6.8) NORTHWEST 27 MPH AUG 22
SEP 6.0 (6.2) EAST 52 MPH SEP 7
OCT 5.4 (6.3) EAST 39 MPH OCT 25
NOV 6.7 (8.0) WEST 38 MPH NOV 24
DEC 9.0 (9.3) EAST 42 MPH DEC 2
2020 6.8 MPH (7.5) EAST WIND 52 MPH SEP 7
BAROMETRIC PRESSURE EXTREMES...
HIGHEST PRESSURE30.64 INCHES 24 FEB
LOWEST PRESSURE 29.32 INCHES 13 NOV
==============================================================
2020 MAJOR RIVER EXTREMES
WILLAMETTE RIVER (AT MORRISON ST BRIDGE, DOWNTOWN PORTLAND)...
HIGHEST 11.8 FT 3 JUN 2020 (FLOOD STAGE IS 18.0 FT)
LOWEST 0.2 FT 26 OCT 2020
COLUMBIA RIVER (AT INTERSTATE BRIDGE)...
HIGHEST 12.1 FT 3 JUN 2020 (FLOOD STAGE IS 16.0 FT)
LOWEST 0.0 FT 26 OCT 2020
===============================================================
PORTLAND AIRPORT CLIMATE PERIOD OF RECORDS... OCT 1940 TO 2020
PORTLAND AIRPORT CLIMATE NORMALS BASED ON... 1981 TO 2010
===============================================================
DATA COMPILED BY ROCKEY
NATIONAL WEATHER SERVICE PORTLAND OREGON
ONLINE AT: WEATHER.GOV/PORTLAND
$$