NWS CLI archive · settlement source
CLISEA · 시애틀 · America/Los_Angeles · ← 2026-09-19 · 2026-09-21 → · All dates for KSEA · JSON · METAR-derived record
Final issued 2026-09-21 04:27:00 EDT · Product id iem:CDUS46-KSEW-210827:SEA:2026-09-20:final · IEM archive
Product id iem:CDUS46-KSEW-210827:SEA:2026-09-20:final · iem-afos · IEM archive
SHA-256 b11f9d51ce001f28a0b912bf66cc026d38b280a138a394c9ed35415951a1dc82
Product text
CDUS46 KSEW 210827
CLISEA
CLIMATE REPORT
NATIONAL WEATHER SERVICE SEATTLE
127 AM PDT MON SEP 21 2026
...................................
...THE SEATTLE-TACOMA WA AIRPORT CLIMATE SUMMARY FOR SEPTEMBER 20 2026...
CLIMATE NORMAL PERIOD 1991 TO 2020
CLIMATE RECORD PERIOD 1945 TO 2026
WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST
VALUE (LST) VALUE VALUE FROM YEAR
NORMAL
...................................................................
TEMPERATURE (F)
YESTERDAY
MAXIMUM 70 419 PM 88 1974 71 -1 73
MINIMUM 50 557 AM 40 1949 53 -3 52
AVERAGE 60 62 -2 63
PRECIPITATION (IN)
YESTERDAY 0.00 1.05 1972 0.05 -0.05 0.00
MONTH TO DATE 1.03 0.96 0.07 0.06
SINCE OCT 1 37.94 38.69 -0.75 28.97
SINCE JAN 1 21.16 22.75 -1.59 15.57
SNOWFALL (IN)
YESTERDAY 0.0 MM MM 0.0
MONTH TO DATE 0.0 0.0
SINCE OCT 1 3.0 2.3
SINCE JUL 1 0.0 0.0
SNOW DEPTH 0
DEGREE DAYS
HEATING
YESTERDAY 5 4 1 2
MONTH TO DATE 61 51 10 16
SINCE SEP 1 61 51 10 16
SINCE JUL 1 86 106 -20 40
COOLING
YESTERDAY 0 1 -1 0
MONTH TO DATE 2 29 -27 34
SINCE SEP 1 2 29 -27 34
SINCE JAN 1 267 262 5 328
...................................................................
WIND (MPH)
RESULTANT WIND SPEED 4 RESULTANT WIND DIRECTION N (350)
HIGHEST WIND SPEED 10 HIGHEST WIND DIRECTION NE (30)
HIGHEST GUST SPEED 15 HIGHEST GUST DIRECTION N (20)
AVERAGE WIND SPEED 5.6
SKY COVER
AVERAGE SKY COVER 0.2
WEATHER CONDITIONS
THE FOLLOWING WEATHER WAS RECORDED YESTERDAY.
FOG
RELATIVE HUMIDITY (PERCENT)
HIGHEST 97 200 AM
LOWEST 57 300 PM
AVERAGE 77
..........................................................
THE SEATTLE-TACOMA WA AIRPORT CLIMATE NORMALS FOR TODAY
NORMAL RECORD YEAR
MAXIMUM TEMPERATURE (F) 70 88 1952
1974
MINIMUM TEMPERATURE (F) 53 39 1955
1960
SUNRISE AND SUNSET
SEPTEMBER 21 2026.....SUNRISE 655 AM PDT SUNSET 709 PM PDT
SEPTEMBER 22 2026.....SUNRISE 656 AM PDT SUNSET 706 PM PDT
- INDICATES NEGATIVE NUMBERS.
R INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T INDICATES TRACE AMOUNT.
$$Product id iem:CDUS46-KSEW-210118:SEA:2026-09-20:interim · iem-afos · IEM archive
SHA-256 bf7902d71c95009c0b6646fd176dbd96c91f9d65f5a04c82b42a6df248fbdd23
Product text
CDUS46 KSEW 210118
CLISEA
CLIMATE REPORT
NATIONAL WEATHER SERVICE SEATTLE
618 PM PDT SUN SEP 20 2026
...................................
...THE SEATTLE-TACOMA WA AIRPORT CLIMATE SUMMARY FOR SEPTEMBER 20 2026...
VALID TODAY AS OF 0500 PM LOCAL TIME.
CLIMATE NORMAL PERIOD 1991 TO 2020
CLIMATE RECORD PERIOD 1945 TO 2026
WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST
VALUE (LST) VALUE VALUE FROM YEAR
NORMAL
...................................................................
TEMPERATURE (F)
TODAY
MAXIMUM 70 419 PM 88 1974 71 -1 73
MINIMUM 50 557 AM 40 1949 53 -3 52
AVERAGE 60 62 -2 63
PRECIPITATION (IN)
TODAY 0.00 1.05 1972 0.05 -0.05 0.00
MONTH TO DATE 1.03 0.96 0.07 0.06
SINCE OCT 1 37.94 38.69 -0.75 28.97
SINCE JAN 1 21.16 22.75 -1.59 15.57
SNOWFALL (IN)
TODAY 0.0 MM MM 0.0
MONTH TO DATE 0.0 0.0
SINCE OCT 1 3.0 2.3
SINCE JUL 1 0.0 0.0
SNOW DEPTH 0
DEGREE DAYS
HEATING
TODAY 5 4 1 2
MONTH TO DATE 61 51 10 16
SINCE SEP 1 61 51 10 16
SINCE JUL 1 86 106 -20 40
COOLING
TODAY 0 1 -1 0
MONTH TO DATE 2 29 -27 34
SINCE SEP 1 2 29 -27 34
SINCE JAN 1 267 262 5 328
...................................................................
WIND (MPH)
RESULTANT WIND SPEED 3 RESULTANT WIND DIRECTION N (0)
HIGHEST WIND SPEED 10 HIGHEST WIND DIRECTION NE (30)
HIGHEST GUST SPEED 15 HIGHEST GUST DIRECTION N (20)
AVERAGE WIND SPEED 5.7
SKY COVER
AVERAGE SKY COVER 0.2
WEATHER CONDITIONS
THE FOLLOWING WEATHER WAS RECORDED TODAY.
FOG
RELATIVE HUMIDITY (PERCENT)
HIGHEST 97 200 AM
LOWEST 57 300 PM
AVERAGE 77
..........................................................
THE SEATTLE-TACOMA WA AIRPORT CLIMATE NORMALS FOR TOMORROW
NORMAL RECORD YEAR
MAXIMUM TEMPERATURE (F) 70 88 1952
1974
MINIMUM TEMPERATURE (F) 53 39 1955
1960
SUNRISE AND SUNSET
SEPTEMBER 20 2026.....SUNRISE 654 AM PDT SUNSET 711 PM PDT
SEPTEMBER 21 2026.....SUNRISE 655 AM PDT SUNSET 709 PM PDT
- INDICATES NEGATIVE NUMBERS.
R INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T INDICATES TRACE AMOUNT.
$$Settlement source: the final NWS Climatological Report (CLI) for station KSEA for the contract date, as archived verbatim at https://weathermarket.io/nws-cli/KSEA/2026-09-20 with links to the NWS product and the IEM archive. A CORRECTED re-issue published before the settlement time supersedes earlier issues.
The settlement value for a date is the latest final CLI issued for that date; a corrected re-issue supersedes earlier issues. Interim same-day products never settle. This is the same rule that fills values.nwsOfficial in /api/station/{icao}/daily.
Every issue is stored verbatim as received - nothing is edited or re-derived. Products are held from 2026-09-01 (backfilled from the IEM AFOS archive) and ingested live from api.weather.gov since 2026-11-10, polled every 30 minutes. A date with no final CLI 14 hours after local midnight is reported as not_issued rather than filled in.