Weathernotes Archive January 2003

Weathernotes for Monday, January 27, 2003

Everyone is asking, "What's happened to El Nino?" News stories comparing this year's El Nino to 1997's are asking where's all the rain? With only a trace of rain, downtown Los Angeles will record one of the four driest Januarys since record keeping began in 1877. Even so, as a result of storms to our north and storms earlier this season, the Sierra snowpack is reported to be about 119% of normal for the date.

Despite what you might have heard on the news, this year's moderate strength El Nino is almost exactly what forecasters predicted. The Multivariate ENSO Index (MEI) for November/December increased somewhat to 1.15, which ranks 10th highest over a period of 53 years, but is not nearly as strong as the MEI value of 2.22 recorded for Nov/Dec 1997. Early on forecasters cautioned that the impacts from this year's El Nino were not expected to be as severe as in 1997-98.

So when is it going to rain? Most medium range forecasts keep the southern half of California dry into the first week of February. The ECMWF is somewhat stronger with a trough due through this weekend, but current ensemble forecasts suggest significant precipitation in Southern California is unlikely. In the longer term, most outlooks continue to forecast wetter than average weather for Southern California. For example, according to the IRI climate outlook for February to April there is a 50% chance that precipitation in Southern California will be in wettest one-third historically for that period, and a 30% chance it will be in the middle third, and only a 20% chance it will be in the lower third. We'll see!

More information concerning Southern California weather can be found using our WEATHER LINKS page.

Weathernotes for Monday, January 6, 2003

Last night all the ingredients for a strong offshore wind event combined to produce hurricane strength wind gusts in some areas of the Southland. Trees, powerlines, and even power poles were reported down in several areas.

Early this morning the Cheseboro RAWS station near the Los Angeles and Ventura county line recorded a gust of 92 mph, and sustained winds of 55 mph. Several gusts at Cheseboro were in excess of 70 mph. The Chilao RAWS in the San Gabriel Mountains recorded gusts exceeding 80 mph in each of three consecutive hours.

Rather than El Nino rains, the first few days of January have been characterized by unseasonably warm, dry weather, with highs in downtown Los Angeles in the 75-80 degree range. If current AVN model forecasts verify, a persistent high amplitude upper level ridge will keep things mostly dry through the middle of the month. Some showers could result from weak features undercutting the ridge, or from wrap-around moisture from retrograding upper level lows associated with the ridging, such as the one currently over Arizona. We'll see!

More information concerning Southern California weather can be found using our WEATHER LINKS page.