Weather in Whatcom County

Calculated from weather data of Bellingham International Airport (KBLI) between 2020 and 2024.

Maximum temperatures (°F)

Month	Average	2024	2023	2022	2021	2020
January	46.0	43.0	48.0	45.0	49.0	47.0
February	45.0	49.0	46.0	46.0	44.0	47.0
March	52.0	52.0	53.0	53.0	53.0	50.0
April	58.0		56.0	55.0	61.0	59.0
May	66.0		69.0	60.0	64.0	67.0
June	70.0		69.0	69.0	75.0	68.0
July	75.0		74.0	76.0	76.0	73.0
August	75.0		76.0	78.0	74.0	74.0
September	69.0		69.0	72.0	68.0	72.0
October	59.0		59.0	64.0	57.0	58.0
November	51.0		50.0	47.0	51.0	51.0
December	45.0		49.0	38.0	39.0	48.0
Average	58.0	48.0	60.0	59.0	59.0	59.0

Average highest temperature per day

The maximum temperature is typically observed some hours after noon.

Minimum temperatures (°F)

Month	Average	2024	2023	2022	2021	2020
January	35.0	33	38	34	38	36
February	34.0	37	35	35	35	36
March	38.0	38	36	41	38	36
April	43.0		42	40	42	42
May	49.0		51	47	48	49
June	53.0		53	53	56	53
July	57.0		56	58	58	56
August	57.0		57	58	58	56
September	53.0		51	52	52	54
October	45.0		44	46	46	47
November	39.0		36	33	42	40
December	35.0		39	28	31	37
Average	44.0	36.0	45.0	44.0	45.0	45.0

Average lowest temperature per day

The minimum temperature is typically observed just before sunrise.

Cold and hot days

Number of days	2024	2023	2022	2021	2020
86 °F or warmer	0	0	6	7	2
77 °F or warmer	0	28	36	31	24
68 °F or warmer	0	107	102	93	96
32 °F or colder	16	48	52	33	30

Precipitation (%)

Month	Average	2024	2023	2022	2021	2020
January	17.6	28	19	11	20	25
February	18.3	16	19	14	26	18
March	13.0	11	16	16	11	8
April	12.3		18	8	8	7
May	8.8		8	17	6	11
June	10.0		8	13	12	14
July	2.5		2	2	0	7
August	2.6		1	1	4	4
September	8.2		5	1	16	7
October	14.1		13	12	22	10
November	17.9		8	15	34	18
December	20.0		23	14	21	20
Average	12.2	18.0	11.0	9.8	13.9	11.6

Precipitation during daylight period

Percentage of observations with observed rain, drizzle, snow or hail. Only observations between sunrise and sunset are taken into account.

Wind speed (miles per hour)

Month	Average	2024	2023	2022	2021	2020
January	8.5	8	7	7	8	11
February	8.7	8	8	7	9	6
March	8.0	7	8	7	8	9
April	8.1		9	8	7	7
May	6.7		7	7	7	7
June	7.5		8	6	7	7
July	7.4		8	6	8	7
August	6.7		6	6	7	7
September	6.2		6	6	6	6
October	6.4		6	6	8	7
November	7.9		5	7	8	9
December	7.2		5	8	10	7
Average	7.5	7.7	6.9	6.8	7.7	7.4

Average wind speed

Excluding wind gusts. Only observations between sunrise and sunset are taken into account.

Prevailing wind direction

Month	2024	2023	2022	2021	2020
January	NE	E	SE	SE	SE
February	E	SE	E	E	S
March	S	SE	SE	S	SE
April		S	S	S	SE
May		S	S	S	S
June		S	S	S	S
July		S	S	S	S
August		S	S	S	S
September		S	SW	S	S
October		NE	S	SE	S
November		E	NE	S	S
December		E	NE	NE	SE

Prevailing wind direction

Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.

Whatcom County weather Q&A

What is the warmest month in Whatcom County?

The warmest month is August with an average temperature of 75 °F over the past years.

What is the coldest month in Whatcom County?

The coldest month is December with an average daytime temperature of 45 °F in the past few years.

Which month is the wettest in Whatcom County?

Chance of precipitation is the highest in December with a probability of around 20.0 %.

Which month is the driest in Whatcom County?

The least rainfall and snow can be expected in July. The probability is about 2.5 %.