Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 259 AM EST Thu Dec 24 2015 Valid 12Z Thu Dec 24 2015 - 12Z Sat Dec 26 2015 ...Rain and mountain snow expected to continue over much of the western U.S. through Christmas Eve... ...Widespread anomalous warmth expected east of the Rockies... ...Numerous showers and thunderstorms are likely from the Gulf Coast to the Mid-Atlantic states... The next two days will be featured with an amplifying flow pattern aloft that will result in a strong storm system developing over the south-central U.S. by Saturday morning. In addition, ridging aloft and at the surface is expected to continue over the southeastern U.S., and a trough over the western U.S. along with much colder weather and snow showers over the Intermountain West and Rocky Mountains. Recording breaking warmth will be one of the things making weather headlines for the end of this week. Conditions reminiscent of spring are expected for most locations across the southern Plains and extending eastward to the East Coast. Large scale southerly flow from the tropics, along with the jet stream being much farther north than usual, will result in May-like warmth and humidity all the way to the Ohio Valley and southern New England going through Friday. Expect widespread 60s and 70s for daytime highs, and 50s and 60s for overnight lows for much of the eastern U.S. through Thursday. Some locations across the southeastern U.S. will likely reach 80 degrees between now and Christmas Day, and some places may even set record highs for the month of December! These readings are on the order of 30 degrees above normal for some areas. The other weather story will be the widespread rainfall in the forecast from the Gulf Coast to the Ohio Valley where amounts on the order of 1 to 3 inches is likely through Saturday morning. Excessive rainfall outlooks are in effect for parts of these areas, where flash flooding could be an issue. The severe weather threat is expected to diminish for Thursday and Friday after the widespread severe storms on Wednesday. D. Hamrick Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php