Below average temperatures lingering in the Northeast this past weekend are not extreme but are several degrees colder than models forecast as arctic air typically erodes slowly. Warming in the wake of last week’s intense arctic air outbreak will continue to be limited through the 1st half of this coming week by snow and/or ice […]
Cold weekend ahead in the Midwest but computer models are latching onto only brief near seasonal cooling in the South and East followed by fast return of above average warmth to predominate the rest of October and early November.
Winter-like cold air emanating from northern Canada is on the move through the northern Rockies and northern Plains, while weakening substantially as it spreads into the summer-like warm and humid air-mass lingering in the South and East. longer range models are latching onto another strong and extended cooling event across the eastern half of the […]
Below average temperatures lingering in the Northeast this past weekend are not extreme but are several degrees colder than models forecast as arctic air typically erodes slowly. Warming in the wake of last week’s intense arctic air outbreak will continue to be limited through the 1st half of this coming week by snow and/or ice events models forecast across the northern U.S. and as far south as the southern Appalachians as several milder Pacific storms eject east of the Rockies. More importantly a strong midweek storm exiting the East Coast is forecast to tap into the coldest arctic airmass yet in Canada virtually ensuring plummeting late week temperatures across the Eastern 3rd of the country extending deep into the Southeast and Florida at 15° below average intensity or greater by this weekend (Dec 21-22). Unlike most arctic air outbreaks observed since Thanksgiving a less intense glancing blow of cold air spilling into the central U.S. will only produce slightly below average temperatures across Texas. Milder temperatures in the central-southern Plains are related to much warmer model shifts across Western North America generating several days of record warmth across the Desert Southwest (near 80°) during the latter half of this week. Longer range implications of strong Western warming scouring arctic air out of western Canada extend milder flow across the Eastern half of the U.S. potentially producing the longest stretch of above average temperatures yet this winter between the end of December into early January. Latest 30-day MWA ensemble runs also latched onto this warmer 11-15 day signal, but still sharply cool the Eastern U.S. below average much of January starting early in the 2nd week of the month. In support latest CFSv2 model mean January forecasts continue to trend colder favoring predominance of seasonal to below average midwinter temperatures east of the Rockies.
