Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 307 PM EDT Mon Apr 23 2018 Valid 00Z Tue Apr 24 2018 - 00Z Thu Apr 26 2018 ...Unsettled weather is expected across the central Appalachians, Mid-Atlantic, the Northeast for Tuesday and Wednesday with areas of locally heavy rainfall... ...Some snow is possible over parts of the northern Rockies and northern High Plains... ...Mild and dry weather is expected for the Intermountain West... A storm system currently over the Tennessee Valley will slowly move eastward across the Southeast overnight and then northeast up across the Mid-Atlantic region through Tuesday, and then over the Northeast by the middle of the week. This will result in a couple of days of unsettled weather with areas of locally heavy rainfall and temperatures that will generally be below normal. The heaviest rainfall should tend to be focused across some of the east-facing slopes of the central Appalachians and over the Mid-Atlantic coastal plain where a couple inches of rain can be expected. The rains will be heavy enough that there will be at least some localized concerns for flooding. The storm system will spread widespread rainfall well inland across the interior of the Northeast Tuesday night and through Wednesday as low pressure lifts up along the East Coast. Farther south, a trailing cold front will cross the Florida Peninsula and this will bring some scattered showers and thunderstorms to this area as the front gradually crosses. Meanwhile, farther off to the west, some upper-level energy over the northern Rockies will advance southeastward across the central Plains and central Rockies by Tuesday evening. Sufficient moisture and forcing will be in place for some higher elevation snow and lower elevation rain for areas of the northern Rockies and northern High Plains. This will include the potential for some accumulating snow across areas of the Black Hills. A cold front will be accompanying this energy aloft as it digs down across the Plains and this should lead the way for some much colder temperatures to drop south through the middle of the week. As the front settles south, there will be rain that also focuses farther south down toward the southern Plains and even the lower Mississippi Valley through Wednesday. The Western U.S. should see rather tranquil weather through the middle of the week with dry conditions and mild temperatures. Overall, daytime temperatures are expected to be as much as 10 to 20 degrees above normal across the Great Basin as high pressure aloft settles over the region. Orrison Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php