Unbelievable Great Lakes Ice Time lapse

One of the most impressive time lapses I've seen in a long time. This is from WGN-TV Hancock camera earlier this week (February 21). Look how quickly the ice opens up over Lake Michigan as the winds shift and the temperatures rise. If this doesn't cause you to rethink walking on the ice I don't know what will.

Cracks in the ice are VERY common especially this time of year. Fluctuations in air temperature, wind direction and intensity drive the shifting ice making it more unstable.

Ice coverage across the Great Lakes have reached their peak and are now falling.

LAKE SUPERIOR:   51% on Feb 19th

LAKE MICHIGAN:  335 on Feb 18th

LAKE HURON:     48%  on Feb 20th

LAKE ERIE:           86% on Feb 20th

LAKE ONTARIO:  21% on Feb 18th 

Lake Erie, the shallowest of the lakes is showing significant ice breakup.

FEBRUARY 17

FEBRUARY 19

FEBRUARY 21

ANIMATION OF THE ABOVE IMAGES

FEBRUARY 23

The ice movement forecast through early next week.

Compare this year to the last 2 years:

I checked the years since 2000 that had at least 50% ice coverage on March 1st. The average date where we drop to under 25% ice cover is during the last week of March. This is directly connected to the air temperatures. Based on the long range outlook through the first 7-10 days of March, the ice loss should be gradual.

May Snow & Cold in Cleveland/Northern US

Here in northern Ohio we typically say that if you make it to Tax Day, the chances of seeing snow are pretty remote. Not this year. Late April cold invaded the eastern half of the US and again in early May!  A ton to unpack here so let's get to it.

~2" snow in Auburn Township - May 9, 2020

The month didn't start off super-cold. We had a few days in the 70s during the first weekend. Watch the progression of the cold across the northern US via the RTMA temperatures between May 2nd and 5th.

Historically this is what May should look like.

There have 19 years since 1950 with at minimum snow flurries in May and only a handful of years with measurable snow. I remember May 15, 2016 because I was at a baseball tournament coaching. It was a Sunday and there was snow on the ground at 7am!

Earlier last week, the models were showing a strong surge of cold for Friday/Saturday, May 8-9th. Based upon both the GFS and EURO long range data for Detroit and Pittsburgh--IF verified--this would tie or possibly break the all-time upper level sounding data record for 850mB (5000 feet) cold !set back in 1966 While this isn't where we work and live, this level is critical for determine lake effect snow and surface temperatures.

The sounding history for Detroit shows the EURO forecast for both temperature and 500mB heights at record levels for early May

This is what the 850 mB temperatures read at 8am Saturday morning, May 9th:

Temperatures at 500mB (18,000 feet) were also extremely cold for early May.

Our forecast called for "thundersnow" due to the large temperature change from Lake Erie (45 degrees or 7.5°C) to the temps above (-32°C)

Radar loop Saturday morning showed definitive areas of lake effect

North Royalton

Highest amount: Auburn Township - ~2"

Northern Ohio snow reports - courtesy NWS Cleveland

Northeast snow Saturday May 9, 2020

Check out the progression of record lows Saturday morning across the US.

Core of the cold over the Ohio Valley, Great Lakes and New England Saturday morning.

Wind chill at NWS Cleveland dropped to 20 at 7:51am Saturday May 9th

Has this happened before?  Here are two composite years:  1986 and 1966

After a break Sunday with temperatures near 60 with storms/shelf cloud passage in the early evening...

Vermilion - May 10, 2020

...another clipper front passed through early Monday morning, May 11th. Yet another shot of frontal/lake effect snow!

Chardon - ~2" of snow - May 11, 2020

Hambden Township - May 11, 2020

Mayfield Heights - May 11, 2020

* 2020 marks the only year in Cleveland (NWS Cleveland-Hopkins) since 1954 with multiple days of snow flurries and/or measurable snowfall in the month of May

* New record snowfall this late in the season at NWS Cleveland: 0.2" on May 11th which breaks old record on 5/10/1907

* 5/11/2020 high of 45 was also the COLDEST high temperature in the last 100 years this late in the season (tied 5/11/1996)

We still haven't reach 80 degrees this year. A warm up is coming! (regression to the average which is now nearing 70)

Potential high temperatures Thursday, May 14th

Here are the years when we touched 80 or better after May 15th (since the 1930s). The list is short:

Lake Erie Sunset 5/11/2020

What Is Driving This Cool Pattern? 2014 vs 2009

This unseasonably cool pattern across the Great Lakes and upper mid-west hasn't been completely unexpected. Back in April and early May, we talked about how this summer would feature periods where temperatures would drop below normal. Take a look at the 12 day stretch from July 15th to July 26th. The area of the US that experienced below normal temperatures this year is exactly the same as 2009.

2009 was one of our years we used as a guide in formulating our summer outlook. Remember, this does not include this week's cool-down. I'll redraw this anomaly map at the end of this week.

The upper level (18,000 foot) trough is a bit stronger this year but in the same location as 2009.

Notice where the ridge (high pressure) is located: The western US where the present drought is the most extreme. Drought drives temperatures higher due to the dry ground. The dry ground and heat creates a high pressure ridge. This ridge keeps the dry conditions going further which drives the temperatures higher....and on and on. 

Water temperatures in the Gulf of Alaska are off-the-charts above average this summer (as it was last winter). 

The above normal Gulf of Alaska water temperatures have enhanced the western high pressure ridge by pushing the jet stream further north. The movement of the jet stream is indicated with the red arrow. The strongest portion of the jet stream (highest winds) is shown with the warmer colors over Alaska. The jet on the east side of the ridge dives southeast in the center of the country and bottoms out over the Ohio Valley where the trough is located.

The PNA index is used to measure these pressure patterns across the Northern Hemisphere. When the PNA is positive, the ridge is very strong out west and the trough/low pressure is strong east as it has been since last winter. You can read about it more HERE. 

The southeasterly jet becomes the conveyor belt for frequent rain and thunder events leading to above normal rainfall across much of the Great Lakes, Midwest and Ohio Valley. This also leads to more frequent periods of below normal temperatures.

For perspective, July in Cleveland, Ohio finished the 6th coolest since 1900.

The average high temperature in Cleveland from July 15th to July 31st was the the second coolest on record!

So the warmer Gulf of Alaska water and the drought out west have significantly boosted the high pressure ridge out west which is reinforcing the trough/cool pattern further east across the midwest and Ohio Valley.  This is not a complete list of the drivers of this summer pattern. The weak El Nino, which garnered a lot of attention during the spring, has had an influence too but not to a major degree. The weak El Nino will factor into our winter outlook which I'll talk about in the fall. Let me know of any other major contributors that I've missed.

Bottom line, it doesn't look like this pattern is going to change anytime soon!

Don't Walk on the Lake Erie Ice!

We see people walking on the Lake Erie ice every year when the lake ice cover is significant. Why people would take this chance especially this time of year when the ice becomes very unstable is beyond me. DON'T WALK ON LAKE ERIE THIS TIME OF YEAR!

The lake ice begins to crack and thin as the overall temperatures begin to climb in late March and early April. The sun angle is also higher so the sun is much stronger than what it was a month ago.

Look at the record setting ice cover statistics from the winter of 1977-78. From March 15th to April 9th, the ice went from 95% to 34%.  A loss of 61% in 3 1/2 weeks!

Expect this trend this year heading into early April. Remember, all of this melting and thinning continues to occur even when we have temporary cold spells.

So don't be fooled. Stay away from the ice!