Highlight: Pacific hurricane to cause major Gulf States/East Coast storm mid-to-late week/weekend. Gas population weight HDD forecast: The weekend trend is somewhat cooler for this week and especially next week and nationally averages near to cooler than normal (Fig. 1). A milder than normal forecast for early November is adjusted warmer over the weekend. Fig. 1: CWG population weight gas HDD forecasts using primary models. Possible major East Coast storm into weekend: The remains of Category 4 Major Hurricane Willa move across Mexico Wednesday merging with a frontal system to produce heavy rains in the Gulf States mid-to-late week. This system moves northeastward along the East Coast this weekend running into a cold air mass seeping south from snow-covered Canada to produce a large 1 or 2 coastal storms which could produce heavy snow over the Appalachians (Fig. 2). At the coast high wind and heavy rain are likely SAT/SUN. Fig. 2: The ECMWF model indicates heavy snow this weekend in the Appalachians. Cold: Widespread freeze warning is in effect this morning from the Tennessee Valley into the Carolinas to Virginia. This morning’s big chill extends into the Gulf States/Southeast U.S. averaging 8-16F below normal. Widespread 20’s and some teens in New England. The next morning chill (8-13F below normal) stretches across the U.S. Corn Belt Wednesday morning. Gusty wind brings that cold to the Northeast Corridor to the Carolinas Thursday morning. Very cold (10-15F below normal) Friday morning Mid-Atlantic/New England. Medium-range: No change to the 6-10 day outlook which continues to feature BELOW to MUCH BELOW East and South as another chilly air mass follows a series of East Coast storms. The West is ABOVE to MUCH ABOVE during the 6-10 day period. The TREND is colder West and warmer East and (very) stormy in-between for the Central U.S. Mega-cluster at 360 hours: The favored upper air pattern is a change to ridge in the East and trough in the West for the first weekend in November (Fig. 3). Fig. 3: About an equal split between the ECM, GFS and CMC (models) averages an Interior West trough and Northeast ridge for the first weekend in November.