Frost Dates for Tri-City, OR

Based on data from Riddle weather station, 3 miles away

Elevation: 741 ft

Frost Dates

Last Spring Frost (50%) March 31

First Fall Frost (50%) November 6

30% Probability

Last Spring Frost April 11

First Fall Frost October 26

Hard Freeze (28°F)

Last Spring Hard Freeze February 20

First Fall Hard Freeze December 10

42.98°N, 123.31°W © OpenStreetMap

Growing Season

220 Days March 31 to November 6

USDA Hardiness Zone

Zone 9a

Avg. annual minimum: 20 to 25°F

Learn more

Köppen Climate

Csb Warm-Summer Mediterranean

Warm, dry summers and mild, wet winters. Similar to hot-summer Mediterranean but cooler. Great for a wide range of vegetables and fruit trees with moderate water needs.

Köppen climate map

Temperature

30° 50° 70° 90°

45°

Jan

47°

Feb

50°

Mar

54°

Apr

60°

May

65°

Jun

72°

Jul

71°

Aug

66°

Sep

57°

Oct

49°

Nov

44°

Dec

32°F

Avg High Avg Temp Avg Low Light Frost (32°F)

Temperature table

Average monthly temperatures (°F)
Month	Avg High	Avg Temp	Avg Low
January	53°	45°	37°
February	57°	47°	37°
March	62°	50°	39°
April	66°	54°	41°
May	74°	60°	47°
June	80°	65°	51°
July	88°	72°	55°
August	89°	71°	54°
September	84°	66°	49°
October	71°	57°	43°
November	58°	49°	41°
December	51°	44°	37°

Precipitation

0" 1" 2" 3" 3.9"

3.4"

Jan

2.6"

Feb

2.8"

Mar

2.7"

Apr

2.5"

May

2.1"

Jun

0.5"

Jul

0.0"

Aug

1.9"

Sep

2.5"

Oct

3.5"

Nov

3.9"

Dec

Precipitation table

Average monthly precipitation (inches)
Month	Precipitation
January	3.4
February	2.6
March	2.8
April	2.7
May	2.5
June	2.1
July	0.5
August	0.0
September	1.9
October	2.5
November	3.5
December	3.9

Sunrise / Sunset

Jan: 7:48 AM – 4:58 PM · 9h 10m

Feb: 7:19 AM – 5:37 PM · 10h 18m

Mar: 7:34 AM – 7:13 PM · 11h 39m

Apr: 6:38 AM – 7:49 PM · 13h 11m

May: 5:56 AM – 8:24 PM · 14h 28m

Jun: 5:39 AM – 8:48 PM · 15h 09m

Jul: 5:53 AM – 8:45 PM · 14h 52m

Aug: 6:25 AM – 8:10 PM · 13h 46m

Sep: 6:60 AM – 7:16 PM · 12h 17m

Oct: 7:35 AM – 6:22 PM · 10h 48m

Nov: 7:14 AM – 4:43 PM · 9h 29m

Dec: 7:44 AM – 4:35 PM · 8h 51m

Daylight Pacific Time (PT) Longest: 15h 11m · Shortest: 8h 50m

Sunrise and sunset table

Sunrise, sunset, and daylight on the 15th of each month (Pacific Time (PT))
Month	Sunrise	Sunset	Daylight
January	7:48 AM	4:58 PM	9h 10m
February	7:19 AM	5:37 PM	10h 18m
March	7:34 AM	7:13 PM	11h 39m
April	6:38 AM	7:49 PM	13h 11m
May	5:56 AM	8:24 PM	14h 28m
June	5:39 AM	8:48 PM	15h 09m
July	5:53 AM	8:45 PM	14h 52m
August	6:25 AM	8:10 PM	13h 46m
September	6:60 AM	7:16 PM	12h 17m
October	7:35 AM	6:22 PM	10h 48m
November	7:14 AM	4:43 PM	9h 29m
December	7:44 AM	4:35 PM	8h 51m

Nearby Stations

Roseburg Kqen, OR March 23 - November 18 Roseburg Rgnl AP, OR March 19 - November 20 Winchester, OR March 31 - November 5 Sexton Summit, OR May 16 - October 30 Idleyld Park 4 Ne, OR April 27 - October 19 Powers, ORMarch 21 - November 14

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