Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 358 AM EDT Mon Oct 03 2016 Valid 12Z Mon Oct 03 2016 - 12Z Wed Oct 05 2016 ...Heavy rain possible over parts of the Northern Rockies/High Plains... ...Temperatures will become 10 to 15 degrees below average over parts of California into the Great Basin and the Northern Rockies... A deep upper-level low will move from the Pacific Northwest/northern California northeastward to the northern High Plains by midweek. A surface low will spin up and deepen over eastern Montana and will drag a cold front through the northern and central Plains. Anomalous moisture feeding into the system will yield higher precipitation amounts across portions of the Northern Rockies and eastern Montana. The higher terrain will likely get snow, and as temperatures cool down, the snow levels will steadily lower. 1 to 3 inches (liquid) will be possible. Snow accumulations for the Little Belts and the Beartooth Ranges may reach a foot by early Wednesday morning. The system will advance into the the Dakotas and central Plains. Strong to severe thunderstorms are forecast to initiate over portions of Oklahoma, Kansas and Nebraska along and ahead of the front Tuesday afternoon. Please refer to the Storm Prediction Center's website for additional information on the locations and severity of the thunderstorms. Some of these storms may also produce periods of heavy rainfall, which could increase the risk for flash flooding over northern Missouri and southern Iowa. Meanwhile, another area of upper-level energy will begin to move onshore over the Northwest by Tuesday morning. Pacific moisture will stream onshore ahead of the advancing low tonight and into Tuesday will bring rain to portions of Washington, Oregon and northern California. Across the East surface high pressure will settle in and the upper-level low will continue to weaken as it moves from the lower Great Lakes region through the Northeast. The cold front that was associated with the upper-level low will continue to push eastward across the Atlantic, but will slow and stall by Tuesday. Lingering rain will be possible today for portions of southern New England and northern Mid-Atlantic and into Tuesday. Additionally, onshore flow off the Atlantic will aid in producing showers and thunderstorms over parts of the Southeast through Tuesday. Campbell Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_wbg.php