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Posted at 1:15 PM ET, 10/14/2010

Grading our 2010 summer outlook

By Matt Ross

* Rain gives way to wind: Full Forecast | Latest climate rhetoric *

As resilient as this year's heat has been, maybe, just maybe, highs in the 80s earlier this week were summer's last hurrah. Before we look ahead to winter, let's recap and grade our 2010 summer outlook.

It was, as most everyone surely knows, a historically hot summer replete with shattered records throughout. Suffice to say, we didn't forecast the hottest summer on record or a tie for the most 90-degree days in a year. But for a seasonal outlook, we did pretty darn well.

Keep reading for your chance to grade our summer 2010 outlook...


We called for all three months of meteorological summer -- June, July and August -- to average above normal for temperature. That forecast verified, though to an extreme far beyond anyone's wildest expectations.

June finished more than 6 degrees above normal, compared to our prediction of 1 to 2 degrees above normal, blowing the old June record away by more than a degree (which is a lot when it comes to monthly averages). We had the same 1 to 2 degrees above normal forecast for July, which ended up tying for warmest July on record at almost 4 degrees above normal. Our call for August was 1 degree above normal and was our closest to being correct, with August "only" finishing 2.7 degrees above normal.

For the summer as a whole, we predicted temperatures would average 1 to 2 degrees above normal. The actual June-July-August average?... a whopping 4.3 degrees above normal, smashing the old record of 3 degrees above normal from 1980.


In the precipitation department, we were mostly on the mark with our forecast of "Below normal. Perhaps, well below." All three airports finished the summer with below-normal rainfall, and the far western suburbs were very dry. The region was dry enough through the summer and earlier in the year to prompt the Metropolitan Washington Council of Governments to issue a "drought watch" in early September, which was lifted about a month later after heavy rains reduced the region's rainfall deficit.


Regarding some of our mores specific predictions, which were more for fun than anything else...

  • We called for 1 to 2 100-degree days. We had 4.
  • We predicted 40-45 90-degree days during June-July-August, which was well above the normal of 31 but still fell short of the actual 52.
  • We called for the longest streak of 90-degree days to be 10 to 12 days, and in fact it was 12 days.

Survey says...

Overall, I would grade our outlook a B. We got the general idea correct that it would be a hot summer and that all three months would be warmer than normal. We just didn't anticipate the history-making potential. Though even if we had, would anyone have believed a forecast for a record hot summer following a record snowiest winter? The odds of such a double whammy were low, but as it turned out all too real.

Stay tuned for our winter outlook around Nov. 1.

By Matt Ross  | October 14, 2010; 1:15 PM ET
Categories:  Local Climate, Recaps  
Save & Share:  Send E-mail   Facebook   Twitter   Digg   Yahoo Buzz   StumbleUpon   Technorati   Google Buzz   Previous: Hot times for climate change science rhetoric
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Is the science of meteorology advanced enough to enable long-range forecasting of extreme events that occur once-in-a-generation or, in the case of last year's snows, once-in-several lifetimes?

A-minus at worst for the summer forecast and even that's harsh.

(I watched the DCA cooling degree days very closely and even in mid-to-late August, I didn't think the 1980 record of just over 2,000 would be broken. The 2010 CDD days are now up to 2,110, roughly 33% higher than average. Almost unimaginable.)

Posted by: JerryFloyd1 | October 14, 2010 2:00 PM | Report abuse

I have to applaud you guys for grading yourselves. I don't know of many forecasters (looking at you CBS, ABC, NBC, Weather Channel) which would go back and see how you did for a season prediction. You guys got it mostly right and I would give you at worst an A-

Posted by: buckeye96 | October 14, 2010 3:05 PM | Report abuse


Easy question: "Is the science of meteorology advanced enough ....."

NO, and it will probably never be possible.

Posted by: SteveT-CapitalWeatherGang | October 14, 2010 3:58 PM | Report abuse

I gave you guys an A. Hopefully, you can maintain your 4.0 GPA for the winter forecast!

Posted by: david_in_stafford | October 14, 2010 5:09 PM | Report abuse

If you had predicted what really happened this summer, we would have hated you for it. Thanks for softening it a bit while not lulling us into a false hope for coolness. You can say you did it on purpose.

Posted by: jenniej | October 14, 2010 9:02 PM | Report abuse

Probably a "B" for the entire summer, but it didn't seems quite so dry as some previous hot summers until September. We got several thunderstorms at critical times which reduced precipitation stress at least until Aug. 20.

The hurricane season here was a complete "bust", which accounted for the extremely dry month between Aug. 20 and Sept. 20. Nearly all the tropical systems avoided this area. In fact this year was a great year for those recurving "fish storms" which have little or no impact this side of Bermuda.

I think the next two weeks see a light but non-killing frost, followed by a distinct Indian Summer towards Halloween or early November. Tom Skilling is saying that Chicago is enjoying a normal La Nina fall, likely to be followed by a "volatile" winter.

Posted by: Bombo47jea | October 15, 2010 2:01 PM | Report abuse

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