Returning once more this evening to the extended range global temperatures from the European flagship full-physics ensemble — the control (HRES) and the ensemble mean. Both show remarkable Northern Hemisphere land cooling to more than 1.2°C below normal, and the global number to near the 30-year normal (1991-2020). This is widespread, extreme cold for North America and Eurasia into the end of January.

Ensemble Mean | Day 10.5

Control (HRES) | Day 10.5

Control (HRES) Day 14

Temperature Anomaly Next 6-days —> Arctic blasts on repeat with multiple cold fronts / storm systems —> very active pattern.

Southeast Snowfall Event — potential for accumulating snowfall from Florida to Carolinas —> Saturday night through Sunday

Headlines Wednesday Evening

• Great Lakes snowfall machine cranked up for the next several days — with huge snowfall totals along the lakes

• Cold front crashing through Southeast will reach Florida by Friday morning with freezes through Orlando

• Another Arctic blast dialed up for this weekend — cold front crashes through Eastern U.S. but with chance of snowfall on tail end as moisture from Gulf of Mexico crawls northward.

• Could a frontal wave “catch fire” along this Arctic air mass boundary and develop into an impactful Nor’easter? Stars are aligning for East Coast snowfall into early next week.

Florida / South Georgia Snowfall

Wow! This is still 4-days away & in model world that could mean poof or double-down on snowfall amounts. Seems like the solution is trending toward a LOT more snowfall in recent forecast cycles.

Cold Friday Morning Behind Arctic Front

Lower 20s across Georgia and the Carolinas — maybe even teens into North Florida

Very cold in Florida to Orlando with lower 30s or even upper-20s well south of Interstate 4

ECMWF AIFS-Single 18z | Height Anomaly (500 hPa) Next 10-days

If you watch several times, then you’ll see the arrival of multiple height anomalies from the Arctic by way of Siberia transported along the “ridge bridge” built up across the Gulf of Alaska.

Multiple Arctic blasts across the Great Lakes and Eastern U.S. in the next 10-days as the Hudson Bay anchored tropospheric polar vortex spins very cold air around it.

ECMWF AIFS-Single 18z | Temperature (500 hPa) Next 10-days

The temperature at 500 mb is the easiest way to highlight the “polar vortex” across North America with the coldest pool at -40°C (pink) with the -25°C contour usually associated with below freezing temperatures at 2-meters (surface).

The Western U.S. and Pacific Northwest ridge is very apparent and firmly entrenched vs. the Hudson Bay / Arctic Canada undulations are dipping southward into the eastern U.S. = cold. The reservoir of cold air remains largely intact through 10-days centered over Ontario/Quebec.

HRRR Next 18-hours Radar | Through Thursday Noon ET

Snowfall next 18-hours —> huge Lake Huron + system snow for Toronto

ECMWF 18z | Precipitable Water Next 6-days | My Favorite Parameter

Multiple Arctic blasts crash out of Canada into the Lower 48 — reaching the Gulf Coast and draining through Florida. Very cold period starting — underway east of the Rockies.

A rare January tropical storm may also be classified in the Eastern Pacific but not impact land.

ECMWF 18z Precipitation Type and Intensity | Next 6-days

3 Clipper systems with snowfall track through Midwest, Great Lakes and Northeast

1. Current storm bombarding Toronto into interior New England

2. Clipper for Friday — Saturday

3. Another early next week

Southeast —> East Coast — Northeast snowfall threat?

The frontal boundary that delivers the snowfall to the Southeast does have a surface low pressure forming off the Mid-Atlantic. If this could edge westward and phase with the cold upper-level trough / polar vortex, then we could see something special (Nor’easter) that is very impactful for Sunday — Monday. Watching closely!

Europe Storm Systems next 6-days

Flagship ECMWF 12z EPS | Temperature Anomaly | Next 15-days

Into Days 10 —> check out the enormous Canadian cold pool and intensity (more than 30°F below normal in the ensemble mean)

NWS Precipitation Next 72-hours

NWS Snowfall Next 72-hours

Lake Effect Snow Machine!

RTMA | Temperature Analysis | 6:30 PM ET

Average Lower 48 temperature was 43.4°F with 64 million below freezing.

Fairbanks finally warmed up out of the -40s but the extreme cold shifted westward with -50s in the interior of Alaska. Yikes!

Temperature Anomaly | 6:30 PM ET

Lower 48 Temperature Anomaly above normal by 6.1°F

Thursday Morning Low Temperatures

175 million below freezing — nationwide average of 26.8°F

Thursday High Temperatures

40 million at least 70°F —> nationwide average of 46.3°F

Only in the mid-30s for Atlanta — bleh!

Friday High Temperatures

Blend of Models | 7 Days Precipitation Total

Blend of Models v5.0 | Total Snowfall Next 7-Days

Western U.S. barely a snowflake —> winter is busted

Lake Effect Snow Machine —> cranks up again!

ECMWF 18z | Snowfall Next 6-days

Yikes! Upwards of 4-6” of snowfall in South Georgia and North Florida

European Winter | Snowfall Next 6-days

ECMWF EPS 12z | Ensemble Median Snowfall Next 14-days

Probability of 0.1-inch or more Snowfall in the next 6-days [18z]

There is an increasing chance > 50% of “some snowfall” from the Florida panhandle through southeast Georgia into the Carolinas.

Probability of 1-inch or more Snowfall in the next 6-days [18z]

10% - 20% chance of at least an inch of snowfall (that’s impressive) from Pensacola to Tallahassee to Savannah.

Probability of 6-inch or more Snowfall in the next 10-days

Ensemble Median Snowfall for Europe Next 14-days

Eurasia Temperature Anomaly | Week 1 and Week 2

Lower 48 Temperature Anomaly | Next 15-days | ECMWF EPS 12z

5-Day Chunk #1 | Temperature Anomaly | Jan 14 - Jan 18

5-Day Chunk #2 | Temperature Anomaly | Jan 19 - Jan 23

5-Day Chunk #3 | Temperature Anomaly | Jan 24 - Jan 28