Climatological Report (Annual)
Issued by NWS Portland, OR

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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


$$


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