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GWES Probabilistic Wave Height Guidance

Use the drop down menus below to change the display.



GWES 000 Hour Wave Height less than 3ft image GWES 006 Hour Wave Height less than 3ft image
000 Hour Wave Height less than 3ft

006 Hour Wave Height less than 3ft

GWES 012 Hour Wave Height less than 3ft image GWES 018 Hour Wave Height less than 3ft image
012 Hour Wave Height less than 3ft

018 Hour Wave Height less than 3ft

GWES 024 Hour Wave Height less than 3ft image GWES 030 Hour Wave Height less than 3ft image
024 Hour Wave Height less than 3ft

030 Hour Wave Height less than 3ft

GWES 036 Hour Wave Height less than 3ft image GWES 042 Hour Wave Height less than 3ft image
036 Hour Wave Height less than 3ft

042 Hour Wave Height less than 3ft

GWES 048 Hour Wave Height less than 3ft image GWES 054 Hour Wave Height less than 3ft image
048 Hour Wave Height less than 3ft

054 Hour Wave Height less than 3ft

GWES 060 Hour Wave Height less than 3ft image GWES 066 Hour Wave Height less than 3ft image
060 Hour Wave Height less than 3ft

066 Hour Wave Height less than 3ft

GWES 072 Hour Wave Height less than 3ft image GWES 078 Hour Wave Height less than 3ft image
072 Hour Wave Height less than 3ft

078 Hour Wave Height less than 3ft

GWES 084 Hour Wave Height less than 3ft image GWES 090 Hour Wave Height less than 3ft image
084 Hour Wave Height less than 3ft

090 Hour Wave Height less than 3ft

GWES 096 Hour Wave Height less than 3ft image GWES 102 Hour Wave Height less than 3ft image
096 Hour Wave Height less than 3ft

102 Hour Wave Height less than 3ft

GWES 108 Hour Wave Height less than 3ft image GWES 114 Hour Wave Height less than 3ft image
108 Hour Wave Height less than 3ft

114 Hour Wave Height less than 3ft

GWES 120 Hour Wave Height less than 3ft image GWES 126 Hour Wave Height less than 3ft image
120 Hour Wave Height less than 3ft

126 Hour Wave Height less than 3ft

GWES 132 Hour Wave Height less than 3ft image GWES 138 Hour Wave Height less than 3ft image
132 Hour Wave Height less than 3ft

138 Hour Wave Height less than 3ft

GWES 144 Hour Wave Height less than 3ft image GWES 150 Hour Wave Height less than 3ft image
144 Hour Wave Height less than 3ft

150 Hour Wave Height less than 3ft

GWES 156 Hour Wave Height less than 3ft image GWES 162 Hour Wave Height less than 3ft image
156 Hour Wave Height less than 3ft

162 Hour Wave Height less than 3ft

GWES 168 Hour Wave Height less than 3ft image GWES 174 Hour Wave Height less than 3ft image
168 Hour Wave Height less than 3ft

174 Hour Wave Height less than 3ft

GWES 180 Hour Wave Height less than 3ft image GWES 186 Hour Wave Height less than 3ft image
180 Hour Wave Height less than 3ft

186 Hour Wave Height less than 3ft

GWES 192 Hour Wave Height less than 3ft image GWES 198 Hour Wave Height less than 3ft image
192 Hour Wave Height less than 3ft

198 Hour Wave Height less than 3ft

GWES 204 Hour Wave Height less than 3ft image GWES 210 Hour Wave Height less than 3ft image
204 Hour Wave Height less than 3ft

210 Hour Wave Height less than 3ft

GWES 216 Hour Wave Height less than 3ft image GWES 222 Hour Wave Height less than 3ft image
216 Hour Wave Height less than 3ft

222 Hour Wave Height less than 3ft

GWES 228 Hour Wave Height less than 3ft image GWES 234 Hour Wave Height less than 3ft image
228 Hour Wave Height less than 3ft

234 Hour Wave Height less than 3ft

GWES 240 Hour Wave Height less than 3ft image
240 Hour Wave Height less than 3ft



Notes on images above:

  • The likelihood of exceedance is shown as a probability of 0 to 100 of waves heights (significant wave height) reaching or being greater than the chosen value.

  • The 90th percentile represents the wave height value that 90% of the ensemble members are either less than or equal to (i.e., 18 feet).

  • The 10th percentile is the wave height value that is represented by 10% of the contributing ensemble members.

  • The mean is defined as the 50th percentile, that is, the wave height value represented reflects half the distribution is above and half is below this value.

  • The maximum value is the highest value produced by any of the 21 ensemble members. It reflects the most severe conditions predicted by the ensemble prediction system.

The data are produced from the Global Ensemble Forecast System (GEFS) which is run every 6 hours and are created with 20 ensemble members.

Additional information for interpreting this data

More information is available from NOAA's Environmental Modeling Center (EMC).