Grading our summer outlook

Hopefully the pleasant autumn weather of late has helped purge another brutal summer from your memory.  Unfortunately, we are here to remind you one last time of that season’s inferno before we can get on with the business of looking ahead to winter.  Here is a quick evaluation of our summer outlook.

Although we did predict all three summer months would be warmer than normal, there will be no back patting.  With the second hottest summer on record, rivaling 2010 (our hottest year), we missed the mark.  We predicted both June and July would be one degree above normal and both were much hotter than that.  June was over 4 degrees warmer than normal. And July over 5 degrees above normal, our warmest July on record by a wide margin. 

We did have a respectable August forecast.  We called for average temperatures one to two degrees above normal and August finished 2.5 degrees above normal.

Overall, we predicted summer to be slightly above normal (by about one degree, or “slightly”) and it finished four degrees above normal for our 2nd warmest summer on record

Unfortunately, we didn’t do particularly well with our other temperature predictions either.  Our call for 25-30 90-degree days (between June and August) fell well short of the actual 47 (the total for all months in 2011 reached 50). 

We had five 100 degree days versus our prediction of just 0-1. And the 16 day heat wave at the end of July easily eclipsed our call for the longest 90+ streak to be 7-9 days. 

One thing we did quite well on was precipitation with a very wet August helping to verify our prediction of slightly to somewhat above normal precipitation for the summer. 

What went wrong?

Less important than indices or hemispheric patterns (like La Nina) that drove our weather, I think the drought in Texas and the Southern Plains was perhaps the biggest contributing factor to our hot summer.  A persistent summer ridge over this region led to extremely hot air masses.  These air masses had little trouble rolling into our area without much moderation, leading to our brutally hot summer. 

Overall, I would give our summer outlook a grade of C/C-.  It was not a good outlook, but correctly predicting above normal temperatures all three months I think saves us from the D/F range.

Stay tuned for our annual winter outlook coming in the next few weeks.

Related:

CWG’s 2011 Summer Outlook (post-summer evaluation, viewing)

CWG’S 2010 Summer Outlook (post-summer evaluation)

CWG’s 2009 Summer Outlook (post-summer evaluation)