Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 244 PM EST Thu Dec 01 2016 Valid 00Z Fri Dec 02 2016 - 00Z Sun Dec 04 2016 ...Heavy rain event across the southern Plains and the western Gulf Coast will begin on Friday... ...Another system to bring precipitation to the Pacific Northwest and snow along the Rockies... An upper level low digging across the southwestern U.S. will deepen over Mexico by Friday. Ahead of this system in the southern Plains--strong southerly winds will tap into moisture from the Gulf of Mexico and transport this moisture across Texas, the western Gulf, and Mexico. This moisture transport will begin on Friday afternoon which will bring showers and thunderstorms to the South Texas region. Expect coverage of precipitation to increase as the day progresses across Texas and by Saturday morning it will begin to spread into the Lower Mississippi Valley. The southern portions of Arizona and New Mexico can also expect precipitation later on Friday and into Saturday. As the upper level low lifts across northern Mexico and moves toward Texas, the bulk of precipitation will continue across southeast Texas and the Lower Mississippi Valley and will also spread across the Southeast. The Pacific Northwest will have continuous rounds of precipitations as weakening/dying fronts track across the region. Onshore flow will bring showers and higher elevation snow across the Cascades and the northern Rockies. Light precipitation can be expected on Thursday; however, on Friday a cold front will approach and move across the Pacific Northwest coast. Precipitation will increase throughout Friday and into Saturday--with snow in the Rockies occurring by Saturday morning. Fanning Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php