EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1152 PM EST TUE FEB 13 2018 VALID 12Z SAT FEB 17 2018 - 12Z WED FEB 21 2018 ...AMPLIFIED PATTERN NEXT WEEK -- COLD TEMPERATURES FOR THE WEST AND MILD FOR THE EAST... ENSEMBLES CONTINUE TO POINT TO AN INCREASINGLY AMPLIFIED PATTERN NEXT WEEK WITH A DEEP WESTERN TROUGH AND A STRONG EASTERN RIDGE. A MULTI-MODEL/ENSEMBLE CONSENSUS OF THE RECENT GFS/ECMWF RUNS OFFERED A GOOD STARTING POINT. AFTER A SNEAKY WINTER WEATHER THREAT FOR THE MID-ATLANTIC INTO THE NORTHEAST EARLY IN THE PERIOD (SAT NIGHT INTO EARLY SUNDAY), TEMPERATURES WILL RISE WELL INTO THE 60S/70S IN THE EAST AS AN APPROACHING COLD FRONT SLOWS DOWN ACROSS THE MIDDLE MISSISSIPPI VALLEY AND BECOMES THE FOCUS FOR SOME LOCALLY MODEST TO HEAVY RAIN NEXT TUE/WED. FARTHER WEST, LOWERING HEIGHTS WILL TAKE THE SNOW LEVEL DOWN TO 1000-2000 FT AND BRING IN MUCH COLDER AIR TO MONTANA (ABOUT 20-30 DEGREES BELOW AVERAGE). MODEST SNOW IS EXPECTED FOR MIDDLE AND HIGHER ELEVATIONS THIS WEEKEND IN WA/OR/ID/MT/WY THAT WILL MOVE SOUTHWARD THROUGH THE GREAT BASIN AND INTERIOR WEST INTO THE SOUTHWEST NEXT WEEK, WITH SOME LIGHTER SNOW SLIPPING EASTWARD ON THE NORTHERN SIDE OF THE PRECIPITATION SHIELD FARTHER EAST. FRACASSO