Station 46027 (LLNR 562) - ST GEORGES - 8 NM NW of Crescent City, CA Image indicating link to RSS feed of recent meteorological observations for station 46027


Conditions at 46027 as of
(3:00 pm PDT)
2200 GMT on 07/19/2026:
     

Click on the graph icon in the table below to see a time series plot of the last five days of that observation.

5-day plot - Wind Direction Wind Direction (WDIR):WNW ( 290 deg true )
5-day plot - Wind Speed Wind Speed (WSPD): 5.8 kts
5-day plot - Wind Gust Wind Gust (GST): 7.8 kts
5-day plot - Atmospheric Pressure Atmospheric Pressure (PRES):29.95 in
5-day plot - Pressure Tendency Pressure Tendency (PTDY):-0.03 in ( Falling )
5-day plot - Air Temperature Air Temperature (ATMP): 52.5 °F
5-day plot - Dew Point Dew Point (DEWP): 51.8 °F
5-day plot - Wind Chill Wind Chill (CHILL): 50.4 °F
5-day plot - Wind Speed at 10 Meters Wind Speed at 10 meters (WSPD10M): 5.8 kts
5-day plot - Wind Speed at 20 Meters Wind Speed at 20 meters (WSPD20M): 5.8 kts
5-day plot -  Wind Speed, Wind Gust and Atmospheric Pressure Combined plot of Wind Speed, Gust, and Air Pressure
Supplemental Measurements
Lowest 1-minute Pressure
Time (PDT)Pressure
2:56 pm29.94 in
Highest 1-minute Wind Speed
Time (PDT)5-day plot - 1-Minute Wind Speed WSPD 5-day plot - 1-Minute Wind Direction WDIR
2:52 pm 5.8 ktsWNW ( 300 deg true )
Previous observations
TIME
(PDT)
5-day plot - Wind Direction
WDIR
 
5-day plot - Wind Speed
WSPD
kts
5-day plot - Wind Gust
GST
kts
5-day plot - Wave Height
WVHT
ft
5-day plot - Dominant Wave Period
DPD
sec
5-day plot - Average Wave Period
APD
sec
5-day plot - Mean Wave Direction
MWD
 
5-day plot - Atmospheric Pressure
PRES
in
5-day plot - Pressure Tendency
PTDY
in
5-day plot - Air Temperature
ATMP
°F
5-day plot - Water Temperature
WTMP
°F
5-day plot - Dew Point
DEWP
°F
5-day plot - Salinity
SAL
psu
5-day plot - Visibility
VIS
nmi
5-day plot - Tide (above MLLW)
TIDE
ft
2026-07-19 02:50 pmWNW 5.8 7.8 6.2 86.6 NW29.95- 52.5- 51.8---
2026-07-19 02:40 pmWNW 7.8 7.8----29.96- 52.7- 52.0---
2026-07-19 02:30 pmWNW 7.8 9.7----29.96- 52.7- 52.0---
2026-07-19 02:20 pm NW 7.8 7.8 6.6-6.5 NW29.96- 52.7- 52.0---
2026-07-19 02:10 pm--- 6.6 86.5 NW--------
2026-07-19 02:00 pmNNW 7.8 9.7----29.96-0.02 53.1- 52.3---
2026-07-19 01:50 pmNNW 5.8 7.8 7.2-6.6 NW29.96- 53.2- 52.5---
2026-07-19 01:40 pm--- 7.2 86.6 NW--------
2026-07-19 01:30 pm NW 3.9 5.8----29.97- 53.2- 52.5---
2026-07-19 01:20 pmNNW 3.9 3.9 7.5 86.8NNW29.97- 53.2- 52.5---
2026-07-19 01:10 pm NW 1.9 3.9 7.5-6.8NNW29.97- 53.1- 52.3---
2026-07-19 01:00 pm NW 3.9 3.9----29.97+0.00 52.9- 52.2---
2026-07-19 12:50 pmNNW 3.9 5.8 7.2 86.8 NW29.97- 52.7- 52.0---
2026-07-19 12:40 pm NW 3.9 5.8----29.98- 52.9- 52.2---
2026-07-19 12:30 pmNNW 3.9 5.8----29.98- 52.9- 52.2---
2026-07-19 12:20 pm NW 3.9 5.8 6.6 86.5 NW29.98- 52.9- 52.2---
2026-07-19 12:10 pmNNW 3.9 5.8----29.98- 53.1- 52.3---
2026-07-19 12:00 pmESE 1.9 3.9----29.98+0.00 54.1- 53.4---
2026-07-19 11:50 amESE 1.9 3.9 7.5 86.8 NW29.98- 54.1- 53.4---
2026-07-19 11:40 amESE 1.9 3.9----29.98- 54.0- 53.2---
2026-07-19 11:30 amESE 1.9 3.9----29.98- 54.0- 53.2---
2026-07-19 11:20 am SE 1.9 3.9 7.5 86.6 NW29.98- 54.0- 53.2---
2026-07-19 11:10 am SE 3.9 5.8 7.5-6.6 NW29.98- 53.8- 53.1---
2026-07-19 11:00 am SE 3.9 5.8----29.98+0.00 53.8- 53.1---
2026-07-19 10:50 am SE 3.9 5.8 8.2 86.6 NW29.98- 53.8- 53.1---
2026-07-19 10:40 am SE 3.9 5.8----29.98- 53.8- 53.1---
2026-07-19 10:30 am SE 3.9 7.8----29.98- 53.6- 52.9---
2026-07-19 10:20 am SE 3.9 5.8 7.2 86.4 NW29.98- 53.6- 52.9---
2026-07-19 10:10 am SE 3.9 5.8----29.98- 53.6- 52.9---
2026-07-19 10:00 am SE 3.9 5.8----29.98+0.00 53.4- 52.7---
2026-07-19 09:50 am SE 3.9 5.8 8.2 86.3 NW29.98- 53.4- 52.7---
2026-07-19 09:40 am SE 1.9 5.8----29.98- 53.4- 52.7---
2026-07-19 09:30 am SE 3.9 3.9----29.98- 53.2- 52.5---
2026-07-19 09:20 am SE 3.9 5.8 8.9 86.7 NW29.98- 53.1- 52.3---
2026-07-19 09:10 am SE 3.9 5.8 8.9-6.7 NW29.98- 53.1- 52.3---
2026-07-19 09:00 am SE 3.9 5.8----29.98+0.01 53.2- 52.5---
2026-07-19 08:50 amSSE 1.9 3.9 8.5 86.5NNW29.98- 53.2- 52.5---
2026-07-19 08:40 amSSE 3.9 5.8----29.98- 53.2- 52.5---
2026-07-19 08:30 am SE 3.9 5.8----29.98- 53.2- 52.5---
2026-07-19 08:20 am SE 3.9 5.8 8.5 86.4 NW29.98- 53.1- 52.3---
2026-07-19 08:10 am SE 3.9 7.8 8.5-6.4 NW29.98- 53.1- 52.3---
2026-07-19 08:00 am SE 3.9 7.8----29.98+0.01 53.1- 52.3---
2026-07-19 07:50 am SE 3.9 7.8 8.2 76.3NNW29.98- 53.2- 52.5---
2026-07-19 07:40 amSSE 3.9 7.8----29.98- 53.4- 52.7---
2026-07-19 07:30 amSSE 3.9 7.8----29.98- 53.6- 52.9---
2026-07-19 07:20 am S 3.9 5.8 7.9 86.2 NW29.98- 53.6- 52.9---
2026-07-19 07:10 am S 3.9 5.8 7.9-6.2 NW29.98- 53.6- 52.9---
2026-07-19 07:00 am S 3.9 7.8----29.98+0.00 53.6- 52.9---
2026-07-19 06:50 am S 3.9 5.8 7.9 86.3NNW29.98- 53.6- 52.9---
2026-07-19 06:40 am S 3.9 5.8----29.98- 53.6- 52.9---
2026-07-19 06:30 am S 3.9 5.8----29.97- 53.8- 53.1---
2026-07-19 06:20 am S 3.9 7.8 7.5 86.2NNW29.97- 53.8- 53.1---
2026-07-19 06:10 am S 3.9 5.8 7.5-6.2NNW29.97- 53.8- 53.1---
2026-07-19 06:00 am S 3.9 5.8----29.97-0.01 54.0- 53.2---
2026-07-19 05:50 am S 3.9 5.8 8.2 86.4 NW29.97- 53.8- 53.1---
2026-07-19 05:40 am S 3.9 5.8----29.97- 53.8- 53.1---
2026-07-19 05:30 am S 3.9 5.8----29.97- 53.6- 52.9---
2026-07-19 05:20 am S 3.9 5.8 7.2 86.0 NW29.97- 53.6- 52.9---
2026-07-19 05:10 am S 3.9 7.8 7.2-6.0 NW29.97- 53.6- 52.9---
2026-07-19 05:00 am S 5.8 7.8----29.97-0.01 53.6- 52.9---
2026-07-19 04:50 am S 5.8 7.8 7.2 86.1 NW29.97- 53.6- 52.9---
2026-07-19 04:40 am S 3.9 7.8----29.97- 53.6- 52.9---
2026-07-19 04:30 am S 3.9 7.8----29.97- 53.6- 52.9---
2026-07-19 04:20 am S 5.8 5.8 7.2 76.1NNW29.97- 53.8- 53.1---
2026-07-19 04:10 am S 5.8 5.8 7.2-6.1NNW29.98- 54.0- 53.2---
2026-07-19 04:00 am S 5.8 7.8----29.98+0.00 54.1- 53.4---
2026-07-19 03:50 amSSW 5.8 7.8 6.6 86.0 NW29.98- 54.5- 53.8---
2026-07-19 03:40 am SW 5.8 7.8 6.6-6.0 NW29.98- 54.7- 54.0---
2026-07-19 03:30 am SW 5.8 9.7----29.98- 54.7- 54.0---
2026-07-19 03:20 am SW 5.8 7.8 7.5 86.3NNW29.98- 54.5- 53.8---
2026-07-19 03:10 am SW 5.8 7.8 7.5-6.3NNW29.98- 54.3- 53.6---
2026-07-19 03:00 am SW 5.8 7.8----29.98+0.00 54.3- 53.6---
2026-07-19 02:50 amSSW 5.8 7.8 7.2 86.1NNW29.98- 54.3- 53.6---
2026-07-19 02:40 am S 7.8 9.7----29.98- 54.3- 53.6---
2026-07-19 02:30 am S 7.8 9.7----29.98- 54.3- 53.6---
2026-07-19 02:20 am S 7.8 9.7 6.9 86.1 NW29.98- 54.3- 53.6---
2026-07-19 02:10 amSSE 5.8 9.7 6.9-6.1 NW29.98- 54.3- 53.6---
2026-07-19 02:00 amSSE 5.8 9.7----29.98+0.00 54.3- 53.6---
2026-07-19 01:50 am SE 5.8 7.8 8.2 86.5NNW29.98- 54.5- 53.8---
2026-07-19 01:40 am SE 5.8 9.7----29.98- 54.5- 53.6---
2026-07-19 01:30 am SE 7.8 11.7----29.98- 54.7- 54.0---
2026-07-19 01:20 amSSE 9.7 11.7 7.5 86.2NNW29.98- 54.5- 53.6---
2026-07-19 01:10 amSSE 7.8 11.7 7.5-6.2NNW29.98- 54.9- 53.6---
2026-07-19 01:00 am S 9.7 11.7----29.98+0.00 55.6- 54.1---
2026-07-19 12:50 am S 7.8 11.7 8.2 86.4 NW29.98- 55.6- 54.0---
2026-07-19 12:40 amSSE 7.8 9.7 8.2-6.4 NW29.98- 55.6- 54.1---
2026-07-19 12:30 amSSE 3.9 7.8----29.98- 55.4- 54.0---
2026-07-19 12:20 amESE 1.9 3.9 8.2-6.5 NW29.98- 55.4- 54.0---
2026-07-19 12:10 am--- 8.2 86.5 NW--------
2026-07-19 12:00 am E 5.8 9.7----29.98+0.01 55.6- 54.0---
2026-07-18 11:50 pmESE 5.8 9.7 7.5 86.5 NW29.98- 55.6- 54.3---
2026-07-18 11:40 pmESE 5.8 7.8----29.98- 55.4- 54.3---
2026-07-18 11:30 pmESE 5.8 7.8----29.98- 55.4- 54.3---
2026-07-18 11:20 pmESE 5.8 7.8 7.2 86.2 NW29.98- 55.4- 54.3---
2026-07-18 11:10 pm SE 5.8 7.8 7.2-6.2 NW29.98- 55.2- 54.1---
2026-07-18 11:00 pmESE 5.8 7.8----29.98+0.01 55.2- 54.1---
2026-07-18 10:50 pmESE 5.8 7.8 7.5 86.3 NW29.98- 55.2- 54.1---
2026-07-18 10:40 pm SE 5.8 9.7 7.5-6.3 NW29.98- 55.2- 54.1---
2026-07-18 10:30 pm SE 3.9 7.8----29.98- 54.9- 54.0---
2026-07-18 10:20 pm E 1.9 3.9 8.5 86.5 NW29.98- 54.5- 53.6---
2026-07-18 10:10 pmNNE 0.0 3.9 8.5-6.5 NW29.98- 54.0- 53.1---
2026-07-18 10:00 pmNNE 1.9 3.9----29.98+0.02 53.8- 52.9---
2026-07-18 09:50 pm N 1.9 3.9 8.2 86.2 NW29.98- 53.4- 52.5---
2026-07-18 09:40 pm N 1.9 3.9----29.98- 53.1- 52.2---
2026-07-18 09:30 pmNNW 1.9 3.9----29.97- 53.2- 52.3---
2026-07-18 09:20 pm NW 3.9 5.8 8.2 86.2 NW29.97- 53.2- 52.3---
2026-07-18 09:10 pm NW 3.9 5.8 8.2-6.2 NW29.97- 52.9- 52.0---
2026-07-18 09:00 pm N 1.9 3.9----29.97+0.00 52.9- 51.8---
2026-07-18 08:50 pmNNE 1.9 3.9 8.5 86.4 NW29.97- 52.9- 51.6---
2026-07-18 08:40 pm N 1.9 3.9----29.97- 53.1- 51.6---
2026-07-18 08:30 pmNNW 1.9 3.9----29.96- 53.4- 52.0---
2026-07-18 08:20 pmNNW 3.9 3.9 8.2 76.2 NW29.97- 53.6- 51.8---
2026-07-18 08:10 pmNNW 3.9 5.8 8.2-6.2 NW29.97- 53.8- 52.0---
2026-07-18 08:00 pmNNW 5.8 7.8----29.97-0.02 53.8- 52.2---
2026-07-18 07:50 pmNNW 5.8 7.8 7.9 86.0 NW29.96- 53.6- 52.2---
2026-07-18 07:40 pmNNW 7.8 7.8 7.9-6.0 NW29.96- 53.8- 52.3---
2026-07-18 07:30 pm N 7.8 9.7----29.96- 54.1- 52.5---
2026-07-18 07:20 pm N 9.7 11.7 7.9 76.1 NW29.96- 54.1- 52.9---
2026-07-18 07:10 pm N 7.8 11.7 7.9-6.1 NW29.96- 53.6- 52.0---
2026-07-18 07:00 pm N 3.9 5.8----29.96-0.05 54.0- 52.2---
2026-07-18 06:50 pmNNW 5.8 7.8 7.2 86.0 NW29.96- 54.1- 52.3---
2026-07-18 06:40 pm N 9.7 9.7 7.2-6.0 NW29.96- 54.1- 52.2---
2026-07-18 06:30 pm N 9.7 11.7----29.96- 54.3- 52.3---
2026-07-18 06:20 pm N 11.7 13.6 6.9 85.8 NW29.97- 54.7- 52.7---
2026-07-18 06:10 pm N 11.7 15.5 6.9-5.8 NW29.97- 54.5- 52.7---
2026-07-18 06:00 pmNNW 13.6 17.5----29.97-0.06 54.5- 52.5---
2026-07-18 05:50 pmNNW 11.7 15.5 6.6 75.8 NW29.96- 54.9- 52.7---
2026-07-18 05:40 pmNNW 9.7 13.6----29.97- 54.9- 52.5---
2026-07-18 05:30 pm N 11.7 13.6----29.98- 54.9- 52.7---
2026-07-18 05:20 pmNNW 11.7 13.6 6.9 75.9NNW29.98- 54.9- 52.7---
2026-07-18 05:10 pmNNW 11.7 13.6 6.9-5.9NNW29.98- 54.9- 52.7---
2026-07-18 05:00 pm N 9.7 11.7----29.99-0.04 54.7- 52.5---
2026-07-18 04:50 pm N 11.7 11.7 6.6 75.9 NW29.99- 54.9- 52.7---
2026-07-18 04:40 pmNNW 11.7 13.6 6.6-5.9 NW29.99- 54.9- 52.7---
2026-07-18 04:30 pmNNW 11.7 13.6----29.99- 55.0- 52.7---
2026-07-18 04:20 pmNNW 11.7 13.6 6.6 76.0NNW30.00- 55.2- 52.9---
2026-07-18 04:10 pmNNW 9.7 11.7 6.6-6.0NNW30.00- 55.2- 52.9---
2026-07-18 04:00 pmNNW 9.7 11.7----30.00-0.04 55.2- 52.9---
2026-07-18 03:50 pm NW 9.7 11.7 6.2 76.0NNW30.01- 55.6- 53.1---
2026-07-18 03:40 pm NW 7.8 9.7----30.01- 56.1- 53.4---
2026-07-18 03:30 pm NW 3.9 5.8----30.02- 56.3- 53.6---
2026-07-18 03:20 pm NW 3.9 5.8 6.6 76.1 NW30.02- 56.5- 53.6---
2026-07-18 03:10 pmNNW 1.9 5.8----30.02- 56.7- 53.8---
2026-07-18 03:00 pmNNW 1.9 3.9----30.02-0.03 56.7- 53.6---
2026-07-18 02:50 pmNNW 1.9 3.9 5.2 75.9 NW30.03- 56.3- 53.4---

Wave Summary
for 46027 as of (2:40 pm PDT)
2140 GMT on 07/19/2026:

These wave data are displayed in rounded times.

     

Click on the graph icon in the table below to see a time series plot of the last five days of that observation.

5-day plot - Significant Wave Height Significant Wave Height (WVHT): 6.2 ft
5-day plot - Swell Height Swell Height (SwH): 6.2 ft
5-day plot - Swell Period Swell Period (SwP): 8.3 sec
5-day plot - Swell Direction Swell Direction (SwD): NW
5-day plot - Wind Wave Height Wind Wave Height (WWH): 1.3 ft
5-day plot - Wind Wave Period Wind Wave Period (WWP): 2.9 sec
5-day plot - Wind Wave Direction Wind Wave Direction (WWD):WNW
5-day plot - Wave Steepness Wave Steepness (STEEPNESS): AVERAGE
5-day plot - Average Wave Period Average Wave Period (APD): 6.6 sec
Previous observations
TIME
(PDT)
5-day plot - Wave Height
WVHT
ft
5-day plot - Swell Height
SwH
ft
5-day plot - Swell Period
SwP
sec
5-day plot - Swell Direction
SwD
 
5-day plot - Wind Wave Height
WWH
ft
5-day plot - Wind Wave Period
WWP
sec
5-day plot - Wind Wave Direction
WWD
 
5-day plot - Wave Steepness
STEEPNESS
 
5-day plot - Average Wave Period
APD
sec
2026-07-19 02:10 pm 6.6 6.6 7.7 NW 1.6 4.0 NW STEEP 6.5
2026-07-19 01:40 pm 7.2 6.9 8.3 NW 1.6 3.7 NW STEEP 6.6
2026-07-19 01:10 pm 7.5 7.2 7.7NNW 1.6 3.8 NW STEEP 6.8
2026-07-19 12:40 pm 7.2 6.9 8.3 NW 1.3 4.0 NW STEEP 6.8
2026-07-19 12:10 pm 6.6 6.2 8.3 NW 1.6 4.0 NW AVERAGE 6.5
2026-07-19 11:40 am 7.5 7.2 8.3 NW 1.6 3.8 NW STEEP 6.8
2026-07-19 11:10 am 7.5 7.2 8.3 NW 2.0 3.7 NW STEEP 6.6
2026-07-19 10:40 am 8.2 7.9 8.3 NW 2.0 3.7 NW STEEP 6.6
2026-07-19 10:10 am 7.2 7.2 8.3 NW 2.0 3.8 NW STEEP 6.4
2026-07-19 09:40 am 8.2 7.9 7.7 NW 2.0 3.4 NW STEEP 6.3
2026-07-19 09:10 am 8.9 8.5 8.3 NW 2.0 4.0 NW STEEP 6.7
2026-07-19 08:40 am 8.5 8.2 7.7NNW 2.0 3.2 WNW STEEP 6.5
2026-07-19 08:10 am 8.5 8.2 7.7 NW 2.3 3.8 NW STEEP 6.4
2026-07-19 07:40 am 8.2 7.9 7.1NNW 2.3 4.0 WNW STEEP 6.3
2026-07-19 07:10 am 7.9 7.5 7.7 NW 2.3 2.9 WNW STEEP 6.2
2026-07-19 06:40 am 7.9 7.5 7.7NNW 2.0 3.8 WNW STEEP 6.3
2026-07-19 06:10 am 7.5 7.2 7.7NNW 2.3 3.7 NW STEEP 6.2
2026-07-19 05:40 am 8.2 7.9 7.7 NW 2.3 4.0 NW STEEP 6.4
2026-07-19 05:10 am 7.2 6.9 8.3 NW 2.3 3.8 NW STEEP 6.0
2026-07-19 04:40 am 7.2 6.9 8.3 NW 2.3 3.8 NW STEEP 6.1
2026-07-19 04:10 am 7.2 6.9 7.1NNW 2.3 3.4 SSW STEEP 6.1
2026-07-19 03:40 am 6.6 6.2 8.3 NW 2.0 3.7 NW AVERAGE 6.0
2026-07-19 03:10 am 7.5 7.2 7.7NNW 2.3 3.6 WNW STEEP 6.3
2026-07-19 02:40 am 7.2 6.9 7.7NNW 2.3 3.6 SW STEEP 6.1
2026-07-19 02:10 am 6.9 6.6 8.3 NW 2.0 3.8 NW AVERAGE 6.1
2026-07-19 01:40 am 8.2 7.9 7.7NNW 2.3 3.6 SE STEEP 6.5
2026-07-19 01:10 am 7.5 7.2 7.7NNW 2.3 3.8 NW STEEP 6.2
2026-07-19 12:40 am 8.2 7.9 7.7 NW 2.0 4.0 NW STEEP 6.4
2026-07-19 12:10 am 8.2 7.9 7.7 NW 2.0 3.6 NW STEEP 6.5
2026-07-18 11:40 pm 7.5 7.5 7.7 NW 1.6 3.7 WNW STEEP 6.5
2026-07-18 11:10 pm 7.2 6.9 8.3 NW 2.0 3.4 NW STEEP 6.2
2026-07-18 10:40 pm 7.5 7.2 8.3 NW 2.0 3.8 NW STEEP 6.3
2026-07-18 10:10 pm 8.5 8.5 7.7 NW 2.0 3.7 NW STEEP 6.5
2026-07-18 09:40 pm 8.2 7.9 7.7 NW 2.3 4.0 NW STEEP 6.2
2026-07-18 09:10 pm 8.2 7.9 7.7 NW 2.0 3.7 NW STEEP 6.2
2026-07-18 08:40 pm 8.5 8.2 7.7 NW 2.3 4.0 NW STEEP 6.4
2026-07-18 08:10 pm 8.2 7.9 7.1 NW 2.3 4.0 NW STEEP 6.2
2026-07-18 07:40 pm 7.9 7.2 7.7 NW 2.3 3.3 NW STEEP 6.0
2026-07-18 07:10 pm 7.9 7.5 7.1 NW 2.3 4.0 NW STEEP 6.1
2026-07-18 06:40 pm 7.2 6.9 7.7 NW 2.6 4.0 NW STEEP 6.0
2026-07-18 06:10 pm 6.9 5.9 7.7 NW 3.9 5.3 NW STEEP 5.8
2026-07-18 05:40 pm 6.6 5.6 7.1 NW 3.0 4.5 NW STEEP 5.8
2026-07-18 05:10 pm 6.9 5.9 7.1NNW 3.3 5.3 NW STEEP 5.9
2026-07-18 04:40 pm 6.6 5.6 7.1 NW 3.0 4.3 NW STEEP 5.9
2026-07-18 04:10 pm 6.6 6.2 7.1NNW 2.6 4.3 NNW STEEP 6.0
2026-07-18 03:40 pm 6.2 5.9 6.7NNW 1.6 3.8 NW STEEP 6.0
2026-07-18 03:10 pm 6.6 6.2 7.1 NW 1.6 4.0 NNW STEEP 6.1

Plot icon Plot of wave energy versus frequency (and period)