Stratospheric Cooling/La Nina Climate Strengthening: Trend Is Away from Important Cold East U.S. in January
12/26/2024, 4:20 am EST
U.S. Gas Population Weight HDD Forecasts Trending Colder/Longer Duration
12/29/2024, 10:02 am EST
Chart of the day: Colder adjustment for Jan. 3-9!
Discussion: Overnight, the U.S. gas population weight HDD forecast for Jan. 3-9 was revised colder by ALL models (except GFS). During Jan. 10-16, U.S. heating demand settles to the 30-year normal. The extended range HDD forecasts for the second half of January are near to below normal. Consequently, Jan. 3-9 is the coldest week of mid-winter.
Medium-range 6-10 Day Forecast Valid January 1-5, 2025 (24-hour change)
Discussion: The operational ECM ENS 6-10-day forecast is colder across Western Canada as the model now believes an arctic air mass will form.
Medium-range 11-15 Day Forecast Valid January 6-10, 2025 (24-hour change)
Discussion: The colder 6-10-day forecast in Western Canada causes the 11-15-day outlook to shift sharply colder as the incoming air mass is moderating arctic air south of snow cover and full-throttle arctic air over Southern Quebec and Northern New England.
U.S. Medium-range Precipitation Forecast
Discussion: The U.S. medium-range precipitation forecast is mostly drier than normal except near the U.S./Canada border where a snowy regime enhances developing cold.
Days 16-20 Extended range Temperature Forecast valid January 11-15, 2025
Discussion: Cold weather lingers East into mid-January. The Northeast turns snowy during the period.