August 2013 General Discussion

[cyclone77]

August wrap up:

 

Average High: 79.7°

Average Low: 59.1°

Overall: 69.5°

 

Departure (High): +0.77°

Departure (Low): -1.68°

Overall: -0.45°

 

Rainfall: 1.83"/4.65cm

 

Highest temperature: 95°

Lowest temperature: 50°

 

5; 90s

9; 80s

14; 70s

3; 60s

 

Summer wrap up:

 

Departure (High): -0.813°

Departure (Low): -1.113°

Overall Departure: -0.963°

 

Rainfall Total: 10.81"/27.46cm

 

Highest temperature: 96°

Lowest temperature: 39°

Spread: 57°

 

Overall a cool and somewhat wet summer. The nights especially were cooler overall compared to normal.

 

Below shows the temperature trend here for the whole year, with summer within the white lines.

The cool late July/early August period stands out quite well!

 

summertemps.png

 

 

Are these temperatures from your location, or is it from KUGN?

[Geos]

Are these temperatures from your location, or is it from KUGN?

 

Well my temperatures were pretty much identical to UGN's. I'd say 98% of what UGN's highs and low are, is what occurs here as well. (within 1°) The rainfall numbers are all mine.

[Jonger]

My closest station ends up at -0.6 LAN.

[Powerball]

Latest NAM and RAP gets us up to about 2000 J/KG of SBCAPE between 00z and 06z this evening.

 

So maybe we can get a few more storms.

[daddylonglegs]

Sprinkles...  this just sucks. 

[IWXwx]

Sprinkles...  this just sucks. 

 

Cloudy, drizzle, and dreary here. Except this is now Sept. DLL.

[michsnowfreak]

The summer of 2013 (from a meteorological standpoint) is in the books!

It was a very comfortable summer overall, some very chilly days, but some very warm humid ones too. Overall tons of "just perfect" days.

 

VERY wet...and DTW finished at the 3rd wettest summer on record with 16.13". In Wyandotte, I recorded 17.47" for the Jun-Aug period. had that been the official total it would have comfortably been the wettest summer on record, and it was certainly my wettest since Ive had a rain gauge (2000).

 

Breakdown of summer 2013 at DTW:

Mean Temp: 71.9F (+0.2F)

Avg High Temp: 80.6F (-0.8F)

Avg Low Temp: 63.1F (+1.1F)

It was a very normal summer overall, but it was technically 0.2F WARMER than normal...and as you see, the culprit is CLEARLY the low temps. There were just 5 days of 90F+, and should we see no more in September, that will mean 2013 saw less than half the normal of 12. All 5 came in a row (July 15-19).
 

Since 1887......20 years had LESS days of 90F+, 7 years were a match (at 5), and 98 years saw MORE 90F+ days. Despite this...the mean temp of 71.9F ranks this summer at 36th warmest (per DTX) since 1875 and I CANNOT stress ENOUGH how this is almost entirely due to LOW temp/UHI (and also since the departure is only +0.2F, it also shows how avg low temps have risen through the years).

 

Breakdown...

 

# of days with high temp BELOW normal: 49

# of days with high temp ABOVE normal: 37

# of days with high temp EXACTY normal: 6

 

# of days with low temp BELOW normal: 33

# of days with low temp ABOVE normal: 49
# of days with low temp EXACTLY normal: 10

 

So MEAN temperature

# of days with avg temp BELOW normal: 41
# of days with avg temp ABOVE normal: 44
# of days with avg temp EXACTLY normal: 7

[Jonger]

The summer of 2013 (from a meteorological standpoint) is in the books!

It was a very comfortable summer overall, some very chilly days, but some very warm humid ones too. Overall tons of "just perfect" days.

 

VERY wet...and DTW finished at the 3rd wettest summer on record with 16.13". In Wyandotte, I recorded 17.47" for the Jun-Aug period. had that been the official total it would have comfortably been the wettest summer on record, and it was certainly my wettest since Ive had a rain gauge (2000).

 

Breakdown of summer 2013 at DTW:

Mean Temp: 71.9F (+0.2F)

Avg High Temp: 80.6F (-0.8F)

Avg Low Temp: 63.1F (+1.1F)

It was a very normal summer overall, but it was technically 0.2F WARMER than normal...and as you see, the culprit is CLEARLY the low temps. There were just 5 days of 90F+, and should we see no more in September, that will mean 2013 saw less than half the normal of 12. All 5 came in a row (July 15-19).

 

Since 1887......20 years had LESS days of 90F+, 7 years were a match (at 5), and 98 years saw MORE 90F+ days. Despite this...the mean temp of 71.9F ranks this summer at 36th warmest (per DTX) since 1875 and I CANNOT stress ENOUGH how this is almost entirely due to LOW temp/UHI (and also since the departure is only +0.2F, it also shows how avg low temps have risen through the years).

 

Breakdown...

 

# of days with high temp BELOW normal: 49

# of days with high temp ABOVE normal: 37

# of days with high temp EXACTY normal: 6

 

# of days with low temp BELOW normal: 33

# of days with low temp ABOVE normal: 49

# of days with low temp EXACTLY normal: 10

 

So MEAN temperature

# of days with avg temp BELOW normal: 41

# of days with avg temp ABOVE normal: 44

# of days with avg temp EXACTLY normal: 7

 

Most sites surrounding DTW were about 2 degrees colder, PWSs. I took a big enough sample to nail that figure down pretty solid.

 

Now, DTW has been built up for quite a few years, so the ranking is partially fair, but you have to wonder what the early days were like in comparison. When DTW was surrounded by corn fields at its beginning.

[michsnowfreak]

Most sites surrounding DTW were about 2 degrees colder, PWSs. I took a big enough sample to nail that figure down pretty solid.

 

Now, DTW has been built up for quite a few years, so the ranking is partially fair, but you have to wonder what the early days were like in comparison. When DTW was surrounded by corn fields at its beginning.

As Ive said many times before, DTW's early days in the 1960-70s were a radiating magnet. On calm, clear nights you'd be hardpressed to find ANY lower temperature reported in SE MI. In fact, the yearly climate summaries of the time used to note (in the climate description of Detroit) the huge difference between DTW to DET (and even DET to downtown) on calm, clear nights or humid summer nights. Now, on the flip side, records from the 1930s-1950s were at DET, and while uhi wasnt a problem then, it WAS an urban NOT suburban area, so low temps were always on the high side of SE MI temps, not necessarily THE highest, but close (probably similar to present-day DTW). Combine those factors with the fact that as it was, the 1930s-50s were a generally mild period and the 1960s-70s a cold one for this region, and the raw numbers of low temp comparisons look ridiculous. (youd be a fool not to think "global cooling" wasnt impending LOL). Now, the 1870s-1920s also saw readings in Detroit proper, but it was less urban.

 

This is why site locations and changing landscapes have a HUGE influence on temperatures of long term climate sites. Your BEST thing to do is find a rural region that is of a very similar population, wooded coverage, etc now as it was 100 years ago...and which has a reliable climate base...to get a TRUE representation of very specific temp trends. And those are proabably hard to find.

[Trent]

Don't forget that wet summers mean cloudier conditions. That easily translates to lower higher temperatures because of clouds and warmer overnight lows. Had it not been as wet/cloudy you would have seen colder lows, conversely the daytime highs would have been warmer. In the end the average temperature would have been about the same. Just take a look at dailies, it's very typical on cloudy days for the low to be above normal but the high at normal or below. On sunny days the lows are normal to below, with highs above.

[Jonger]

Don't forget that wet summers mean cloudier conditions. That easily translates to lower higher temperatures because of clouds and warmer overnight lows. Had it not been as wet/cloudy you would have seen colder lows, conversely the daytime highs would have been warmer. In the end the average temperature would have been about the same. Just take a look at dailies, it's very typical on cloudy days for the low to be above normal but the high at normal or below. On sunny days the lows are normal to below, with highs above.

 

That is true, but thanks to the wunderground PWS network, we can compare DTW to surrounding locations. 

[Stebo]

That is true, but thanks to the wunderground PWS network, we can compare DTW to surrounding locations. 

 

Which is not a valid comparison because unlike any of the NWS ASOS, the calibration and accuracy just isn't there. You just are not going to get the best data from Jim's backyard thermometer.

[Harry]

As Ive said many times before, DTW's early days in the 1960-70s were a radiating magnet. On calm, clear nights you'd be hardpressed to find ANY lower temperature reported in SE MI. In fact, the yearly climate summaries of the time used to note (in the climate description of Detroit) the huge difference between DTW to DET (and even DET to downtown) on calm, clear nights or humid summer nights. Now, on the flip side, records from the 1930s-1950s were at DET, and while uhi wasnt a problem then, it WAS an urban NOT suburban area, so low temps were always on the high side of SE MI temps, not necessarily THE highest, but close (probably similar to present-day DTW). Combine those factors with the fact that as it was, the 1930s-50s were a generally mild period and the 1960s-70s a cold one for this region, and the raw numbers of low temp comparisons look ridiculous. (youd be a fool not to think "global cooling" wasnt impending LOL). Now, the 1870s-1920s also saw readings in Detroit proper, but it was less urban.

 

This is why site locations and changing landscapes have a HUGE influence on temperatures of long term climate sites. Your BEST thing to do is find a rural region that is of a very similar population, wooded coverage, etc now as it was 100 years ago...and which has a reliable climate base...to get a TRUE representation of very specific temp trends. And those are proabably hard to find.

 

 

IF i am not mistaken Coldwater nor Lansing has not moved. Outside of Lansing most of the other sites ( see KBTL..Not the main ones ) have not moved much if at all over the past 100+ years and those that have only moved within the same town and thus not from town to outlying areas and vice versa.

[Jonger]

That is true, but thanks to the wunderground PWS network, we can compare DTW to surrounding locations. 

 

Which is not a valid comparison because unlike any of the NWS ASOS, the calibration and accuracy just isn't there. You just are not going to get the best data from Jim's backyard thermometer.

Too bad you can't calibrate out the additional square miles of added concrete runways. If 1 station reads lower, that's anecdotal evidence, if 15 read lower, that's a pattern.

There is enough landform change to add at least 10+ years of ranking to the summer average at DTW. I'm not sure why this is hard to comprehend.