Quiet End to Meteorological Summer

Yesterday marked the end of meteorological summer which runs from 6/1-8/31.  Technically, summer ends on or around 9/21 each year, but for meteorological records, June, July, and August (JJA) are considered the summer months.  So how did this summer fare compared to others?  It definitely ended much cooler than we have experienced over the last few years.  I have also noticed that rainfall distribution became more sporadic as summer progressed.  The great drought of 2012 has been eaten away some, but it slowly returning as we head towards typically drier months.  And of course, there is the hurricane season or lack thereof. . .

I just went through some statistics for JJA and here’s what I found:

Philadelphia, PA:
Average High Temperature:  84.6, Average Low Temperature:  68.7
Average Temperature:  76.6 which was 0.6 above normal
Total Precipitation:  29.71", which was 6.14" above normal
Atlantic City, NJ:
Average High Temperature: 83.2, Average Low Temperature: 64.9
Average Temperature: 74.1, which was 0.3 above normal
Total Precipitation: 13.86", which was 0.97" above normal
Baltimore, MD:
Average High Temperature: 84.8, Average Low Temperature: 66.7
Average Temperature: 75.8, which was 0.8 above normal
Total Precipitation: 11.71", which was 0.30" above normal
Ft. Lauderdale, FL:
Average High Temperature: 88.1, Average Low Temperature: 77.2
Average Temperature: 82.7, which was 0.3 above normal
Total Precipitation: 32.25", which was 7.03" above normal
Lake Charles, LA:
Average High Temperature: 92.6, Average Low Temperature: 74.3
Average Temperature: 83.4, which was 0.9 above normal
Total Precipitation: 9.48", which was 7.86" below normal

I will try to have a few other cities in a future post as I know this is a very small sample. From these five cities, average temperatures were slightly above normal, while precipitation was above normal in the East, but much below normal in the western Gulf Coast.

Where do we go from here?

Climate Prediction Center (CPC) Seasonal Temperature Forecast for September, October, and November (SON).
Climate Prediction Center (CPC) Seasonal Temperature Forecast for September, October, and November (SON).
CPC Seasonal Precipitation Forecast for SON.
CPC Seasonal Precipitation Forecast for SON.

The Climate Prediction Center (CPC) issued their Fall 2013 forecast last month. As you can see from the first image, above normal temperatures are predicted for the Great Lakes, Northeast, and the Desert Southwest. The rest of the country is expected to be near normal. Precipitation is forecast to be above normal for Montana and the middle of the country, while the rest of the country is expected to be near normal. Now, late season tropical systems could certainly wreak havoc on this forecast, so keep that in mind.

CPC Weekly Drought Monitor
CPC Weekly Drought Monitor
CPC Season Drought Outlook
CPC Season Drought Outlook

The Drought Monitor issued last Tuesday shows how drought conditions have spread east from the persistent drought areas (high plains, intermountain west) during the latter part of summer. Areas in the upper Mississippi Valley and along the western Gulf Coast have gotten progressively drier with time, but the Seasonal Drought Outlook issued on August 15th, shows these areas improving over the next few months.

What about the tropics?

GOES-13 infrared imagery with 30-minute GLD-360 lightning density overlaid valid on 09/01/13 (click to animate).
GOES-13 infrared imagery with 30-minute GLD-360 lightning density overlaid valid on 09/01/13 (click to animate).

This area of disturbed weather heading towards the Caribbean will be of special interest over the next few days. I will focus more on the tropics in a future post, including some ideas on why this season has been so quiet. . .even globally!

Thank you for reading!

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