WEATHERAmerica Newsletter, Sunday, April 19, 2026; GENERAL WEATHER PATTERN DISCUSSION

[Larry Cosgrove]

GENERAL WEATHER PATTERN DISCUSSION

METEOBLUE

CIMSS

WeatherBELL (5)

College Of DuPage Weather Laboratory (2)

There may still be some concerns about chilly weather (Intermountain Region, Quebec, and New England) as well as snowfall (central Canada), but Spring has sprung. The second heatwave of the season is finished, and the next two-three weeks will feature a lot of below-normal temperatures in parts of the lower 48 states. But like the snow cover, the coldest values will stay above the Canadian border, and the snow chances will show signs of retreat to higher latitudes between now and May 7.

Typhoon Sinlaku has merged with the polar westerlies, attached to a sprawling vortex over the Bering Sea. That gyre will pump ever-warmer temperatures aloft through Alaska, along the Arctic Circle into Greenland. Enough amplitude in the upper flow will suppress the polar and subtropical jet streams further south. Cold lows embedded in these windfields will close off (we call this cutoff low season), so locations in the southern half of the nations could see some high-impact precipitation and severe weather. The south-central states, particularly Texas in the 6-10 day time frame, may be prone to intense MCS development. I suspect that following seasonal synoptic climatology, this condition could last through the first third of May.

Using ascendant El Nino patterns observed over the past 78 years, warmth should finally return to the West and Central states as we move into mid-May. It could take a bit longer to warm up in the Great Lakes and the Northeast (see the model weeklies). But if what happened in the past repeats itself, the last third of meteorological Spring will trend warm-to-hot over most of the nation outside of the Pacific Northwest.