Rockcreek climate

Rockcreek Weather in May

NOAA 1991-2020 normals for Portland-Hillsboro AP, 5.7 km from Rockcreek

Average highs run from 65°F on May 1 to 71°F on May 31, and lows from 42°F to 47°F. Normal precipitation for the month is 2.02 in over about 12 wet days.

May day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at Rockcreek, in °F, with the record for each date.20406080100151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

May at a glance

Average high
69°F
Average low
45°F
Precipitation
2.02 in
Record high
94°FMay 15, 2006
Record low
30°FMay 8, 2002
Chance of a freeze
16%
Daylight
14 h 20 min to 15 h 27 min
Cloud cover
70%
Humidity
84%
Dew point
48°F
Wind
4.5 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.

DateNormal highNormal lowRecord highRecord lowChance wetChance of snow
May 165°F42°F87°F 201430°F 201345%0%
May 266°F42°F85°F 201631°F 200644%0%
May 366°F42°F90°F 202634°F 201044%0%
May 466°F42°F83°F 201333°F 201043%0%
May 567°F42°F84°F 201334°F 199943%0%
May 667°F43°F84°F 201332°F 200042%0%
May 767°F43°F87°F 201631°F 200242%0%
May 867°F43°F80°F 201530°F 200241%0%
May 968°F43°F86°F 202032°F 200641%0%
May 1068°F44°F88°F 202432°F 201241%0%
May 1168°F44°F88°F 202434°F 200240%0%
May 1268°F44°F87°F 202334°F 201140%0%
May 1369°F44°F92°F 202332°F 202240%0%
May 1469°F45°F90°F 202337°F 200740%0%
May 1569°F45°F94°F 200635°F 200239%0%
May 1669°F45°F93°F 200836°F 200239%0%
May 1769°F45°F92°F 200836°F 200339%0%
May 1869°F45°F85°F 200631°F 200339%0%
May 1970°F46°F85°F 202335°F 200339%0%
May 2070°F46°F81°F 202334°F 202138%0%
May 2170°F46°F85°F 200138°F 202138%0%
May 2270°F46°F94°F 200138°F 200738%0%
May 2370°F46°F88°F 199937°F 200538%0%
May 2470°F46°F81°F 199938°F 201137%0%
May 2570°F47°F83°F 200137°F 200937%0%
May 2670°F47°F86°F 200535°F 201137%0%
May 2770°F47°F94°F 200541°F 201136%0%
May 2871°F47°F92°F 202037°F 200136%0%
May 2971°F47°F87°F 200933°F 200136%0%
May 3071°F47°F91°F 200736°F 199935%0%
May 3171°F47°F92°F 200139°F 202335%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Rockcreek, in percent, and of at least 0.1 inch of snowfall.010203040501102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (PDT).

May 1
sunrise 5:59 AM, sunset 8:19 PM
May 31
sunrise 5:26 AM, sunset 8:53 PM

Every day of May: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USW00094261 (Portland-Hillsboro AP), public domain. Records: NOAA GHCN-Daily, station USW00094261, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.