January 2021 - Climate Impact Company

01/31/2021, 4:08 pm EST

Arctic Outbreak Now More Confidently Forecast for Feb. 6-8!

We’ve watched the GFS project arctic air for the extended-range for about one week generally indicating high intensity but mostly confined to the Central U.S. Last night the GFS indicated the arctic air may stretch into the East with intensity but most models continued to doubt that scenario. This afternoon the ECMWF forecast projects super cold arctic air into the central U.S. next weekend shifting east and southeast with authority for early next week.

01/28/2021, 12:46 pm EST

A Strong Negative Arctic Oscillation Winter 2020-21 But So Far No U.S. Cold

Meteorological winter 2020-21 (so far) is very warm across the U.S. despite presence of a moderate-to-strong negative arctic oscillation also projected to last through February. During 3 analog years when -AO was similarly intense the Central/East U.S. experienced historic cold. The explanation for the warmer winter across the U.S. is related in-part to a constricted polar ice cap and warmer mid-latitude ocean surface.

01/28/2021, 8:11 am EST

Spectacular Cold 11-15 Day Forecast by GFS!

The overnight GFS Operational Model indicates a frigid arctic outbreak into the U.S. in the 11-15 day period. The U.S. gas population weight heating degree day forecast is a whopping 288 HDD for Feb. 5-11.

01/27/2021, 7:04 pm EST

Preliminary 2021 North Atlantic Tropical Cyclone Season Outlook And 2020 Review

The preliminary 2021 North Atlantic tropical cyclone season forecast is attached. The outlook is more active than normal featuring 16 tropical storms, 9 hurricanes and 3 intense hurricanes with an ACE index of 122. The climate conditions feature neutral ENSO and a North Atlantic tropical/subtropical basin not quite as warm as last year.

01/26/2021, 11:43 am EST

Checking Medium-range Temperature Forecast skill Scores of All Models

Not surprisingly the GFS Operational model finishes last in skill scores for forecast 2-meter temperatures in the 6-10 and 11-15 day period across North America. The European Ensemble edges out the American Ensemble for best scores. data provided by CWG/Storm Vista WX Models.

01/26/2021, 11:35 am EST

Alaska Ridge Bridge/Canadian Polar Vortex Days 11-15…But Is It Right?

The highly volatile GFS Operational model indicates a near-perfect set-up to generate Canadian arctic air likely to pour into the U.S. in 2 weeks. The GFS is on its own. Other models are not generating this pattern. A close watch on other models to watch trends toward the GFS solution.

01/25/2021, 10:35 am EST

NCEP CFS V2 Indicates La Nina Could Turn Much Stronger Later This Year

The updated NCEP CFS V2 indicates La Nina continues with moderate intensity through April and intensifies to a “strong” La Nina the second half of the year. The NCEP CFS V2 forecast is in opposition to most other forecast models which favor weakening La Nina in 2021.

01/24/2021, 5:13 pm EST

Cold Spike for New England/Northern Mid-Atlantic Friday/Saturday

Forecast models are in good agreement on a cold spike striking the Northeast U.S. Thursday night/Friday morning and lasting through next weekend. The peak of cold is Friday morning through Saturday morning when very cold temperatures are accompanied by high wind producing extreme wind chill.

01/24/2021, 12:27 pm EST

Madden Julian Oscillation To Intensify

For the first time since November the Madden Julian oscillation is activated and intensifying in the equatorial Pacific Ocean into early February. The result is increased risk of excessive precipitation in the East-central U.S. and a mild climate pattern east of the Continental Divide as the final month of meteorological winter arrives.

01/20/2021, 5:30 pm EST

Early Next Week Winter Storm In The East

Today’s afternoon “European Model” indicated an evolving storm late Sunday night/early Monday centered on Missouri shifting toward West Virginia Monday evening and offshore the northern Mid-Atlantic States Tuesday morning. A wide range of weather is produced by this storm.

01/17/2021, 9:47 am EST

Northern Hemisphere Pattern Change Catalyst for Late January is an Evolving -PNA and +SCAND Pattern

Beginning midweek the northern hemisphere jet stream will trough on the U.S. West Coast and re-strengthen in western Europe. In-between the two vigorous trough patterns a third trough resides south of Greenland. By late January the pattern still remains although with slightly less amplitude. These features shape the last third of January 2021 climate for the northern hemisphere.

01/14/2021, 7:59 am EST

The End of January Northern Hemisphere Pattern

Rather than using any single model the mega-cluster ensemble which accounts for all models projects "most likely" scenarios which are more reliable. The most recent mega-cluster ensemble projection of temperature anomalies for the northern hemisphere in the extended-range (days 11-15) indicates steady presence of the winter 2020-21 arctic air reservoir stretched across Russia.