Our Station
Live: ted on Jul 24 2014, 10:12 pm PDT   Air/Ocean: 70.9/66   Wind: Southeast 7   Surf: 1-3 SW   Rippled Ocean Surface   Sky: Clear 10 miles   Coastal Camera
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How often is weather information updated?
The weather summary located on every page under the drop menu is updated every minute. The weather detail page is updated every 5 minutes with the exception of graphs containing historical weather information. That information is updated every 30 minutes.

Why is beach weather different from the weather 1/2 mile or more inland?
The beach is a unique climate zone. The weather is mild and temperate. The beach weather station is a good resource to compare the numbers. San Clemente beaches are frequently 15 degrees cooler than Mission Viejo during summer months.

Where is the weather station located?
The weather station is located on the San Clemente municipal pier. Readings are taken from 35 ft. above the ocean surface in the surf zone.

What type of equipment is used to gather weather information?
The weather station is a Davis Instruments Vantage Pro Plus. The weather station is linked to a remote internet server to provide worldwide access to the informantion.

What is ET?
Evapotranspiration (ET) is a measurement of the amount of water vapor returned to the air in a given area. It combines the amount of water vapor returned through evaporation (from wet vegetation surfaces and the stoma of leaves) with the amount of water vapor returned through transpiration (exhaling of moisture through plant skin) to arrive at a total. Effectively, ET is the opposite of rainfall, and it is expressed in the same units of measure (Inches, millimeters). This weather station uses air temperature, relative humidity, average wind speed, and solar radiation data to estimate ET. (ET is calculated once an hour on the hour.) NOTE: The ET "K" factor of 1.00 is used, which represents well-watered grass that is uniformly clipped to a few inches in height. Therefore, the ET value at the pier is going to be consistently lower than expected due to the location of the weather station. The humidity is consitantly higher at the beach over the ocean surf. Make appropriate adjustments. The ET represented here should only be used as a rough guide to observe how weather and seasonal changes influance plant water requirements.

What is Dew-Point?
Dew-point is the temperature to which air must be cooled for saturation (100% relative humidity) to occur, providing there is no change in water content. The dew-point is an important measurement used to predict the formation of dew, frost, and fog. If dew-point and temperature are close together in the late afternoon when the air begins to turn colder, fog is likely during the night. Dew-point is also a good indicator of the air’s actual water vapor content, unlike relative humidity, which takes the air’s temperature into account. High dew-point indicates high vapor content; low dew-point indicates low vapor content. In addition a high dew-point indicates a better chance of rain and severe thunderstorms. You can even use dew-point to predict the minimum overnight temperature. Provided no new fronts are expected overnight and the afternoon Relative Humidity ³ 50%, the afternoon’s dew-point gives you an idea of what minimum temperature to expect overnight, since the air is not likely to get colder than the dew-point anytime during the night.

How does the weather station read ocean temperature?
Ocean temperature readings are collected from a sensor probe anchored to the base of a piling on the pier. the probe is located at a depth of 8 feet (at mean tide level). During the lowest tide of the year, the probe will be at a depth of 1 or 2 feet. Readings are transmitted every 10 seconds. Sensitivity of the probe is + - 1.0 degrees. Accuracy is +- .05 degrees. Generally the surface of the ocean is warmer than the water below. The wave wash around the pier pilings helps to mix the warmer water at the surface with the cooler water at lower levels. The mixing helps to produce good temperature readings which represent how cold or warm the ocean feels when surfing or swimming in the surf. Update: Abnormalities in ocean temperature readings have been observed while high tide occurs in the pre-dawn hours. Deep water and absence of solar radiation for many hours produces a cold condition at the sensor depth. During these conditions, readings are 1 to 5 degrees cooler than average mid day temperatures. The readings during these periods should not be relied upon to determine your comfort or a trend.

I want to know more about the weather station at the beach.
Please direct all inqueries to the link below.
EMail about I want to know more about the weather station at the beach.

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