Summer 2011 average temperature (through August 31st)

We love summer, there's no denying it. So it's with heavy hearts that we had to compile the recap of this past summer, as we begin the transition in to fall. Don't worry, we actually love all seasons, but it's definitely harder to let go of the beautiful weather which summer often has to offer. This summer was no different.  As we take a look back, we'll begin to see that it was essentially a summer of two tales, and the last month of the summer became quite anomalous. In fact, much of the summers precipitation was recorded in August and September. The last week of June (when summer begins) into roughly the middle to end of July was not exactly a drought, but definitely featured most of the summers hot days and a general lack of heavy precipitation. Our area observed multiple 100 degree days in July, including one record breaking day on July 22, which saw Newark, NJ set it's all time record high temperature at 108 scorching degrees. Before we continue, we most note that these numbers are not final and do not include the 19 days of September, which technically will factor into the final summer departures and averages. 

TEMPERATURES...

Departure from average temperature (through Aug 31)

To cut straight to the good stuff, Summer 2011 was another above average summer, marking the second in a row since the absolute scorcher that was the Summer of 2010. Average temperatures through August 31st were over 76 degrees in the New York City Metro area. The summer of 2010, for comparison purposes, offered very similar average temperatures, but these high averages were more spread out across the entire Northeast. This summer, there was a sharp gradient over the interior and areas to the North and West. In fact, to our north over New England, average temperatures were nearly 10 degrees cooler.

Temperature departures this summer were generally 2 to 3 degrees above normal throughout the entire area. There were several factors that lead to this--but essentially, the warm start of the summer had our area at nearly 5 degrees above normal as we entered August. However, the relatively average and somewhat cooler month of August knocked down the above average departures to more mediocre levels. In fact, areas of Northwest New Jersey and Southeast New York saw temperature departures of 1 to 2 degrees below average during the month of August, after experiencing a scorching hot July with the rest of us.

Overall, this summer featured temperatures moderately above average, but nearly 2 degrees "cooler above average" than the summer of 2010. On the opposite end of the spectrum, the summer of 2009 ended with temperatures 1 to 3 degrees below average. It has been a tale of three completely different summers over the last three years in our area for sure.

PRECIPITATION...


With the ridge of high pressure built in, providing the historic levels of heat (we mentioned the 105+ degree numbers earlier) and above average temperature departures early in the summer, also came a drier than normal month of July throughout the area. It almost comes with the territory, when you're talking about multiple 100 degree days. As our area began to head into August, precipitation departures were nearly 3 to 5 inches below normal across much of the forecast area. Essentially, the persistent ridge of hot weather and high pressure which was built in over the Central Plains (we are sure you have heard of the historic heat this summer brought them) was flexing it's muscles during the first half of the summer across our area, leaving us generally drier and warmer than normal. Most of our precipitation through August 1st came in the form of scattered showers and thunderstorms, and the occasional extended period of rain along a warm front.

None of us, however, could have seen August coming. In what would become the wettest month in recorded history at New York City, we not only erased the negative precipitation departures, but posted major gains. Our area received over 300 percent of our normal precipitation in the month of August, and we ended the summer with a departure of +10 inches from normal precipitation. Areas near Northwest New Jersey received nearly 15 inches of normal precipitation over the summer. The pattern change from the first half to the second half of the summer in regards to precipitation was truly amazing (and historic) to watch unfold.

WHAT CAN 100 DEGREE DAYS TELL US ABOUT WINTER?

NYC snowfall after multiple 100 degree days in previous summer Credit: Yehuda Hyman

Meteorology is not only about learning from the past events, but also looking to the future. So, you may be asking yourself: what can we learn from summer, that may help us get an idea as to what the winter has to offer? The answer, really, is that the summer can more often than not be a toss up when it comes to being of direct relation to winter forecasting. Much more answers lie in the autumn season, as the pattern begins to change, and we begin to get an idea of the atmospheric transitions which are occurring (see our sea ice level post from this evening). Still, with this being the second summer of multiple 100+ degree days in New York City, we pulled out the statistics for snowfalls after such events in the summer. Having multliple 100 degree days is a rare enough event in New York City itself that we haven't seen it in back to back years since 1953. The last time we saw it, prior to last summer, was 1999, and that winter offered less than 20 inches of snowfall.

However, if the winter of 2010 has anything to say about what's to come, we may be in for another long winter. Additionally, the average snowfall after the previous summer featured multiple 100+ degree says is over 30 inches, higher than the normal average snowfall. So, there may be some argument over time that summer which feature these heating days may be foreshadowing an above average winter. The truth is, we don't truly know what to expect at this point. The spread is too large among the data we've compiled. We'll just have to watch carefully over the next several weeks as we head into autumn, as father time begins to transition us into another one of the four seasons we have the privilege of experiencing in our area.


Article written by John Homenuk, with contributions from Yehuda Hyman. Published September 19th, 2011 at 11:37pm. Looking for a forecast? See New York Metro Weather's Long Range Forecast for current work week, or view our Technical Forecast Discussion for the more serious weather enthusiasts. Also, check out our new Forecast Overview tab. For up to the minute details on forecasts, watches, warnings, and alerts, follow us on Twitter and Facebook.