Portland, OR Weather Forecast and Current Conditions

Day		Sky	High / Low	Precip	Wind	Humidity
Thu Jul 17		Clear Close Hourly	-º / 60º	5%	NNW 8 mph	53%
6pm		Sunny	86º	0%	NNW 6 mph	30%
7pm		Sunny	85º	0%	NNW 7 mph	31%
8pm		Sunny	83º	0%	NNW 8 mph	36%
9pm		Clear	80º	1%	NNW 6 mph	40%
10pm		Clear	77º	1%	NNW 5 mph	47%
11pm		Clear	74º	1%	NNW 4 mph	51%
Fri Jul 18		Mostly Sunny View Hourly	84º / 57º	4%	NW 10 mph	48%
12am		Clear	72º	1%	NNW 3 mph	56%
1am		Clear	70º	3%	NW 2 mph	60%
2am		Clear	68º	3%	NNW 2 mph	64%
3am		Clear	66º	4%	NNW 2 mph	67%
4am		Clear	64º	4%	N 2 mph	72%
5am		Clear	63º	5%	N 2 mph	73%
6am		Sunny	61º	5%	N 1 mph	77%
7am		Sunny	62º	4%	N 2 mph	73%
8am		Sunny	64º	2%	N 2 mph	68%
9am		Sunny	67º	0%	NW 3 mph	63%
10am		Sunny	70º	0%	WNW 4 mph	57%
11am		Sunny	73º	0%	WNW 4 mph	52%
12pm		Mostly Sunny	76º	0%	WNW 5 mph	48%
1pm		Partly Cloudy	79º	0%	NW 6 mph	43%
2pm		Partly Cloudy	81º	0%	NW 6 mph	39%
3pm		Partly Cloudy	82º	0%	NW 7 mph	36%
4pm		Partly Cloudy	83º	0%	NW 8 mph	33%
5pm		Mostly Sunny	82º	0%	NNW 10 mph	32%
6pm		Partly Cloudy	81º	0%	NNW 10 mph	33%
7pm		Mostly Sunny	79º	0%	NNW 10 mph	36%
8pm		Partly Cloudy	76º	0%	NNW 9 mph	41%
9pm		Mostly Clear	72º	0%	NNW 8 mph	47%
10pm		Partly Cloudy	69º	1%	NNW 7 mph	52%
11pm		Mostly Clear	66º	2%	NNW 6 mph	57%
Sat Jul 19		Partly Cloudy View Hourly	80º / 56º	5%	NW 8 mph	52%
12am		Mostly Clear	64º	3%	NNW 6 mph	61%
1am		Mostly Clear	63º	4%	NNW 5 mph	66%
2am		Mostly Clear	61º	5%	NNW 4 mph	68%
3am		Partly Cloudy	60º	5%	NNW 3 mph	71%
4am		Mostly Clear	59º	5%	NNW 3 mph	74%
5am		Mostly Clear	58º	6%	NNW 3 mph	77%
6am		Partly Cloudy	58º	6%	N 2 mph	79%
7am		Partly Cloudy	59º	5%	NNW 3 mph	75%
8am		Partly Cloudy	60º	3%	NNW 3 mph	71%
9am		Partly Cloudy	62º	2%	NNW 4 mph	66%
10am		Partly Cloudy	63º	1%	NW 4 mph	62%
11am		Partly Cloudy	66º	1%	NW 4 mph	57%
12pm		Mostly Sunny	68º	0%	WNW 4 mph	53%
1pm		Mostly Sunny	71º	0%	NW 5 mph	47%
2pm		Mostly Sunny	73º	0%	NW 5 mph	43%
3pm		Mostly Sunny	76º	0%	NW 5 mph	40%
4pm		Mostly Sunny	78º	0%	NW 6 mph	37%
5pm		Partly Cloudy	78º	0%	NNW 7 mph	36%
Sun Jul 20		Partly Cloudy	78º / 59º	5%	NW 6 mph	53%
Mon Jul 21		Partly Cloudy	76º / 58º	24%	NW 4 mph	61%
Tue Jul 22		Sunny	84º / 60º	7%	NW 6 mph	57%
Wed Jul 23		Sunny	89º / 60º	4%	NW 7 mph	52%
Thu Jul 24		Partly Cloudy	86º / 59º	4%	NW 7 mph	53%

• Buoy Data

  For Portland, OR

• Wind Forecast

  In Portland, OR

• Radar

  In Portland, OR

• Marine Forecast

  In Portland, OR

General Weather Conditions in Portland, OR

The coast range provides limited shielding from the maritime influence of the Pacific Ocean. The Cascade Range provides a steep high slope for the lifting moisture-laden westerly winds, which produces heavy rainfall in the western Cascade piedmont region. They also form the barrier for the Columbia River basin region and dry continental air masses. Airflow is usually northwest in Portland in spring and summer and southeast in fall and winter, interrupted occasionally by outbreaks of dry continental air east through Cascade passes and across ridge tops. When such an outbreak occurs, extreme high or low temperatures are usually experienced in the Portland area.

Portland has a very definite winter rainfall climate. About 88 percent of the annual total occurs in October through May, nine percent in June and September, while only 3 percent comes in July and August. The average annual precipitation is 37.33 inches (948.2 mm). December is the wettest month, and July, the driest. Precipitation is mostly rain; on the average only 17 days each year have snow. Snowfall is seldom more than a couple of inches, and it generally lasts only a few days. The annual average is only seven inches (178 mm) with January having the most. Snowfall has fallen in every month from November through May. The greatest measured snowfall in 24 hours was just under 11 inches (279 mm) recorded in January 1971.

Each season is clearly marked. Winter is mild, cloudy and wet with southeast surface winds predominating. Summer is marked by mild temperature, with prevailing northwest winds and very little precipitation. Fall and spring are transitional in nature, with frequent periods of ground fog. An average of 18 days during October record foggy conditions while only three days during July can expect fog. At all times, incursions of marine-tempered air are a frequent moderating influence. Outbreaks of continental air from east of the Cascade Mountains flow through the Columbia Gorge at near sea level and spread into the Portland area associated with the movement of Pacific storms offshore on a northeast storm track. In winter this brings the coldest weather, and the extremes of low temperature are registered in the cold airmass. Freezing rain and ice glaze often are transitional effects. In summer the hot, dry, continental air brings the highest temperatures. Extreme temperatures below zero are very infrequent. The absolute lowest ever reached is 3°F below zero (-19.4°C) recorded in February 1950. Extreme temperatures above 100°F (37.8°C) have occurred during each month from May through September; the absolute highest temperature is 107°F (41.6°C) recorded in July 1942, July 1965 and August 1981. Temperatures 90°F (32.2°C) or higher are reached every year, but seldom persist for more than 2 or 3 days before the warm spell is broken by a flow of cool, moist air from the ocean. The average annual temperature for Portland is 53.9°F (12.1°C). The average maximum is 63°F (17.2°C) while the average minimum is 45°F (7.2°C).

Destructive storms are infrequent in the Portland area. Surface winds seldom exceed gale force. Thunderstorms are infrequent, occurring, on average, only seven days each year. Tornadoes with the funnel cloud reaching the ground are rare and there are rare occurrences of heavy rain even though winter rains may persist for days at a time. Ice forms occasionally, but it is seldom heavy enough to affect navigation seriously, although navigation by small craft may be difficult.