“When we set up that pressure differential, that’s when we get strong winds,” Garcia said. The collision of different temperatures and pressures create extreme weather events. However, that jet stream dived south and collided with the warm, high-pressure bubble that was sitting over the Bay Area. Usually, the jet stream hits the Pacific Northwest and creates storms there. This is what causes the storms in the north and the swells along the coast. In La Niña years, a low-pressure jet stream sweeps the north Pacific. “We were sitting under a bubble of high pressure,” Garcia said. Temperatures in the area averaged in the 70s with clear skies, which is unseasonably warm for January, which is about 10 degrees to 15 degrees warmer than normal. Warm weather and sunshine graced the greater Bay Area, as the beaches packed with people and residents went for walks in shorts and t-shirts, last week. Typically, the swell brings storms with it, but this year the California coast got the benefit of the big swells and got to enjoy nice weather. Sometimes that activity passes the contiguous United States and head toward Hawai’i, in other cases, it hits landfall sooner in California, he said. In a La Niña year, the North Pacific becomes very active with storms, which creates a lot of ocean activity. The waves are the result of this being a La Niña year, according to Garcia. (Shmuel Thaler – Santa Cruz Sentinel file) In the case of snowfall, the total precipitation is given in centimetres.People at Lighthouse Point in Santa Cruz are enveloped in a thick fog on the morning of Jan. If the precipitation falls as water or sleet, the total precipitation is given in millimetres.
The total precipitation is given in inches.
For example in temperatures just above freezing, snowfall with the water content of 10 millimetres of water forms a snow layer 10 centimetres thick on the ground, but in temperatures around -20 degrees Celsius the layer formed by same amount of water is 20 centimetres thick. If the water content of the rain is kept constant, the colder the weather, the thicker a layer the falling snow forms on the ground.įor example in temperatures just above freezing, snowfall with the content of a quarter of an inch of water forms a 2,5 inches thick layer of snow on the ground, but in temperatures around -5 degrees Fahrenheit the same amount of water forms a layer of snow 5 inches thick. Temperatures also affect how much a given amount of snowfall grows the amount of snow on the ground. These factors cause the amount of snow on the ground to grow less than the snowfall amount. The total snowfall refers to the snowfall from the cloud and does not take into account local melting, packing or drifting of snow. The total precipitation forecast gives the expected total precipitation for the whole 24-hour day. Please note that especially in inland locations wind gusts can be up to 1,5 to 2,5 times stronger than the 10-minute average wind speed. The wind forecast shows the strongest expected 10-minute average wind speed of the day. Unlike the daily weather symbol, the temperatures, wind information and total precipitation take into account the whole 24-hour day. Daily temperatures, wind information and total precipitation The cloudiness on the daily weather symbol is calculated as a weighted average of the predicted cloudiness of that day, with most weight assigned to the afternoon hours. You can see the more precise timing and intensity of the rain in the hourly forecast. The rain can be light rain that falls for a longer time period, or a heavy rain of short duration. The amount of rain drops on the daily weather symbol represent the total precipitation amount of that day. The weather in the evening or night time do not show on the symbol. The daily weather symbol gives an overview of the weather between 7 a.m.