837
CXUS56 KSEW 011044
CLMSEA

CLIMATE REPORT
NATIONAL WEATHER SERVICE SEATTLE
344 AM PDT THU OCT 01 2026

...................................

...THE SEATTLE-TACOMA WA AIRPORT CLIMATE SUMMARY FOR THE MONTH OF SEPTEMBER 2026...

CLIMATE NORMAL PERIOD 1991 TO 2020
CLIMATE RECORD PERIOD 1945 TO 2026

WEATHER         OBSERVED          NORMAL  DEPART   LAST YEAR`S
                VALUE   DATE(S)   VALUE   FROM     VALUE DATE(S)
                                          NORMAL
................................................................
TEMPERATURE (F)
RECORD
 HIGH             98   09/02/1988
 LOW              35   09/27/1972
HIGHEST           78   09/09         MM      MM       91  09/16
LOWEST            46   09/28         MM      MM       50  09/25
                                                          09/26
AVG. MAXIMUM    68.0               71.6    -3.6     73.1
AVG. MINIMUM    52.7               53.6    -0.9     55.2
MEAN            60.3               62.6    -2.3     64.2
DAYS MAX >= 90     0                0.2    -0.2        1
DAYS MAX <= 32     0                0.0     0.0        0
DAYS MIN <= 32     0                0.0     0.0        0
DAYS MIN <= 0      0                0.0     0.0        0

PRECIPITATION (INCHES)
RECORD
 MAXIMUM        6.17   2013
 MINIMUM           T   1991
TOTALS          1.46               1.61   -0.15     0.76
DAILY AVG.      0.05               0.05   -0.00     0.03
DAYS >= .01        8                8.3    -0.3        6
DAYS >= .10        6                4.2     1.8        2
DAYS >= .50        1                0.9     0.1        0
DAYS >= 1.00       0                0.2    -0.2        0
GREATEST
 24 HR. TOTAL   0.67   09/12 TO 09/13

DEGREE DAYS
HEATING TOTAL    133                102      31       51
 SINCE 7/1       158                158       0       MM
COOLING TOTAL      2                 30     -28       34
 SINCE 1/1       267                263       4       MM
................................................................

WIND (MPH)
AVERAGE WIND SPEED              7.1
HIGHEST WIND SPEED/DIRECTION    26/160    DATE  09/25
HIGHEST GUST SPEED/DIRECTION    37/150    DATE  09/25

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.62
NUMBER OF DAYS FAIR            4
NUMBER OF DAYS PC             16
NUMBER OF DAYS CLOUDY         10

AVERAGE RH (PERCENT)     73

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              0     MIXED PRECIP               0
HEAVY RAIN                0     RAIN                       3
LIGHT RAIN               11     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       0
HEAVY SNOW                0     SNOW                       0
LIGHT SNOW                0     SLEET                      0
FOG                      10     FOG W/VIS <= 1/4 MILE      1
HAZE                      1

-  INDICATES NEGATIVE NUMBERS.
R  INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T  INDICATES TRACE AMOUNT.

$$