Updated Climate Status and Outlook

Climate Status and Outlook During December 2008, changes in oceanic and atmospheric conditions occurred in the regions of the central and eastern Equatorial Pacific. These changes indicate that La Niña conditions have developed. According to the Climate Prediction Center, the recent trends, current observations, and model forecasts indicate that La Niña conditions are likely to continue into the Spring months of this year. Although the La Niña conditions have developed unusually late into this winter season, the Climate Prediction Center indicates that the effects of La Niña conditions can still occur across different regions of the world, in the January through March time frame. The latest 90-day Outlook for Temperature, from the Climate Prediction Center, for February through April, indicates an enhanced probability for temperatures to average above normal across West-Central Texas. Their 90-day Outlook for Precipitation, for February through April, shows equal chances for precipitation to be above, near, or below normal across West- Central Texas. It should be noted that the 30-day Precipitation Outlook, for the month of February, shows slightly enhanced chances for below normal precipitation across roughly the southern half of West-Central Texas. Implications The latest 90-day Outlook encompasses the transition in seasons from late winter to early spring. The higher probability for above normal temperatures, across our region, reflects the anticipated effects of La Niña conditions. Winter precipitation is usually below normal across West-Central Texas during the stronger La Niña events. The effects of La Niña on precipitation are less pronounced during the spring months. This is due to the influence of smaller scale weather systems, like thunderstorms and thunderstorm complexes. These can bring heavy rainfall to smaller, more localized areas. As a result, rainfall amounts can be quite variable over short distances. The influence of these smaller scale systems cannot be accounted for in the long-range outlooks. Possible Impacts Drought Conditions- With the dry weather pattern which has prevailed in our region during the past several months, drought conditions have worsened, especially across southern and central sections of West-Central Texas. This is reflected in the latest Drought Monitor (issued January 13th). The worsening drought situation is having an adverse effect on agricultural conditions across Texas. The details of these effects are described in the latest USDA Texas Crop Weather Report. The possible effects of the La Niña pattern indicate the potential for drought conditions to expand or deteriorate further, through the remainder of this winter and into the early spring. Increased Fire Weather Concern- If warmer and drier than normal conditions persist, grass and brush will continue to lose moisture and will be critically dry. The January through March time frame is when strong weather disturbances and storm systems can bring strong, gusty winds and intrusions of very dry air into our region. These combined factors would bring an increased threat for wildfires. Links with Additional Information Local Drought Information Page (at National Weather Service, San Angelo) Latest Diagnostic Discussion from the Climate Prediction Center More Detailed Narrative Description of La Niña, from the Climate Prediction Center