SCOTT'S WORLD OF WEATHER
June is in the books. And what a June it was. Or should I say, 'What a June it wasn't."

It was 21 years ago back in 1988 when we endured one of the hottest weeks EVER in northeastern Ohio weather history. Compare June of 1988 to this year and you will find no similarities. This June, only 3 days above 80 degrees in the first half of the month. The second half, temps went back up to summerlike levels. Everyday but 4 were above 80 with one 90 degree day on the 25th. All told, June, surprisingly, was only a half degree below normal factoring in daytime highs and overnight lows.

Overnight low temperatures aren't that eyecatching because most of us sleep through it so lets look back at the daytime temperatures for the month of June over the last 20 years examining the top 5 coolest months.



You can see that this year is the 5th coolest. 3 of the 5 occurred since 2004. June of 1998, we were coming out of an El Nino spring. In June of 1992, El Nino was still going strong.

Of the top 5 cool Junes, this year was the driest.



Normally, when temps are below normal for a month in the summer, rainfall is well above normal. However this year, June's official rainfall (2.68") was more than an inch BELOW NORMAL and the daytime temperatures stayed relatively cool. If its not rain that kept temperatures cool, what was it?

Let's compare the warmest June over the last 20 years (2005) with this year. Instead of rainfall, look at the percent cloud cover for the month.



Both the warmest June (back in 2005) and this June had virtually the same amount of cloud cover. So its not heavy rain or perpectual cloud cover responsible for our cool June. Where did the cool air come from?

Typically, the winds start to shift from a NORTHERLY flow to a WEST AND SOUTHWESTERLY flow in June. Comparing both Junes and the prevailing wind direction for the entire month, this is what we found.



More than double the number of days with WINDS FROM THE NORTHWEST, NORTH AND NORTHEAST. So the cool weather in June wasn't solely due to increased rainfall and abnormally cloudy days, it was due to winds from the north. In summary, we had just as much sunshine this June as the warmest June in the last 20 years (2005). This June, overall, the cooler days featured more sunshine.

It wasn't just northern Ohio with a slightly below normal June. Most of the western half of the US and New England had an ever colder June.



It looks like this pattern will continue the rest of the summer. We are still expecting maybe one or two more 90 degree days if we are lucky.

Scott's World of Weather Archive:
Northeastern

Ohio Lake Effect - Why Does It Vary So Much?

A Sneak Peak

At Spring

April 3-4,

1974 Tornado Super Outbreak

Summer Outlook

2009

Ohio Tornado

History

Our Cool June, 2009