Climate US Naval Hospital Heliport 2020-2024

Climate and trends: average temperature, flight conditions, precipitation, wind speed and direction.

Calculated from historical METAR data of Guam International Airport (PGUM) between 2020 and 2024.

VFR conditions (%)

Month	Average	2024	2023	2022	2021	2020
January	81.2	85	70	72	91	79
February	83.7	85	78		90	80
March	85.6	83	79	83	90	81
April	84.1		78	81	88	85
May	82.5		73	86	90	79
June	87.7		80	90	87	92
July	84.1		78	80	89	89
August	78.9		65	83	86	84
September	80.3		79	85	86	83
October	80.8		68	81	88	86
November	83.7		78	83	91	88
December	86.5		83	87	95	87
Average	83.4	84.1	75.5	82.6	89.2	84.3

VFR conditions during daylight period

Percentage of observations where the VFR minimums for ceiling and visibility are met: visibility of 8 km or more and a ceiling of 3,000 ft or more. Only observations between sunrise and sunset are taken into account.

Marginal VFR conditions (%)

Month	Average	2024	2023	2022	2021	2020
January	95.9	99	88	91	98	99
February	97.4	97	97		100	97
March	99.0	99	100	99	99	98
April	98.7		99	99	98	99
May	97.8		92	100	98	99
June	98.5		99	98	100	100
July	97.2		96	95	100	98
August	95.3		91	96	98	99
September	95.1		93	95	97	100
October	95.6		91	95	95	97
November	97.8		97	98	100	99
December	98.0		98	97	98	99
Average	97.3	98.0	94.7	96.4	98.3	98.6

Marginal VFR conditions or better during daylight period

Percentage of observations where the MVFR minimums for ceiling and visibility are met: visibility of 5 km or more and a ceiling of 1,000 ft or more. Only observations between sunrise and sunset are taken into account.

Maximum temperatures (°C)

Month	Average	2024	2023	2022	2021	2020
January	29.7	30	30	29	30	29
February	29.8	30	30		30	29
March	30.4	31	30	31	30	31
April	30.7		31	30	31	31
May	31.1		31	31	31	31
June	31.3		31	31	31	32
July	31.0		31	30	31	31
August	30.8		31	32	31	31
September	30.6		31	31	30	31
October	30.5		31	30	30	30
November	30.9		31	31	31	30
December	30.4		31	31	30	30
Average	30.5	29.9	30.7	30.6	30.4	30.5

25th highest temperature of United States

Average highest temperature per day

The maximum temperature is typically observed some hours after noon.

Minimum temperatures (°C)

Month	Average	2024	2023	2022	2021	2020
January	23.5	24	25	22	25	24
February	24.2	22	24		25	24
March	23.7	25	24	23	23	21
April	24.1		25	24	24	22
May	25.6		26	26	26	26
June	25.8		26	25	26	27
July	25.8		25	25	26	26
August	24.9		26	25	25	25
September	25.2		25	25	26	25
October	25.3		26	25	24	25
November	25.5		24	26	25	25
December	24.8		24	26	21	25
Average	24.7	23.4	25.0	24.8	24.6	24.6

Average lowest temperature per day

The minimum temperature is typically observed just before sunrise.

Precipitation (%)

Month	Average	2024	2023	2022	2021	2020
January	9.0	8	18	17	4	4
February	6.6	7	10		1	5
March	5.0	5	11	7	4	3
April	5.5		9	10	4	3
May	5.5		12	2	7	4
June	4.4		8	4	4	2
July	11.2		15	18	8	6
August	14.0		19	9	18	9
September	13.9		18	14	9	15
October	13.2		19	17	16	10
November	6.2		7	9	5	8
December	5.9		9	9	5	3
Average	8.2	6.5	13.0	10.6	7.2	5.8

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 (knots)

Month	Average	2024	2023	2022	2021	2020
January	13.2	14	11	14	13	14
February	14.3	15	15		13	15
March	13.0	14	12	14	12	14
April	12.3		13	14	9	13
May	11.7		13	12	13	12
June	10.3		12	10	8	12
July	9.1		10	9	9	10
August	7.8		8	8	8	7
September	7.4		7	7	8	6
October	8.6		10	8	7	8
November	11.8		13	11	11	12
December	13.5		14	13	12	13
Average	11.3	14.0	11.4	10.5	10.3	11.4

25th highest wind speed of United States

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	063°	076°	065°	079°	067°
February	060°	072°		085°	061°
March	072°	075°	084°	082°	076°
April		084°	090°	101°	081°
May		071°	088°	085°	090°
June		096°	095°	107°	087°
July		096°	108°	110°	094°
August		247°	103°	103°	097°
September		148°	136°	101°	116°
October		094°	117°	106°	104°
November		082°	074°	084°	083°
December		072°	081°	074°	081°

Prevailing wind direction

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