Thursday, November 10, 2016

How Do Current Lake Erie Water Temperatures Compare to Other Warm Years? More Snow?

Lake Erie ice cover from 2011

After the warmest period from June 1st to October 31st on record at the official NWS reporting station at Hopkins Airport, the Lake Erie water temperature is above any of the most recent years with the exception of 2005. 

Average Lake Erie water temperature on November 1, 2005 was 15° Celsius. 
This year: 14.8°C. As of this writing (November 10), the average water temperature is still well above normal at 14.5°C or about 58 degrees F.

This is 5 degrees warmer than the closest years--2007 and 2005!

Each year regardless of the air temperature, the water temperatures dropped significantly to between 0°C and 5°C.

How will this affect lake effect snow?  If a decent shot of arctic air slides across the lake before the water temperatures fall around the first of the year, any lake effect snowfall could be significant.

I wrote several post a FEW YEARS AGO about the subject of Lake Effect snow.

Here are the ingredients for Lake Effect:

1. Temperature difference between the lake and the air aloft (5000 feet) has to be at least 13 degrees celsius. The more, the better.

2. Abundant atmospheric moisture independent of the lake

3. Wind speed

4. Wind direction

5. Fetch Length (How far does the wind blow over the lake)

6. Instability and instability depth (Usually driven by a cold front/trough and/or the lake temperature difference) Deeper the instability, the deeper the snow growth

7. Orographic lift (elevation differences between Cleveland and the snowbelt. 1200 feet in portions of Geauga county)

Even if #1, 3, 4, 5 and 6 are present (the most common variables), subtract any one of these variables especially 2 and 5--sometimes 7 if the wind direction shifts) and snowfall forecasts can turn out much different than anticipated. 

Will we see one of these 3 "flavors" of lake effect snow dominate this winter?  More on this next month.