record degree-days data?

bob carey -midland,mich.

might try your local newspaper. the DETROIT FREE PRESS has a summary of the information for SE michigan. bob

Plumbob

where to find?

It is easy to find, on the net, the record low temperature for my area (Chicago). But that's not particularly useful for heating purposes, because the record was probably reached for only a few minutes in th middle of the night. Maybe the day that had the all-time record low of (say) -27F also had a high temperature of +23F; who knows.

I want to find the record low value for the average of the area's daily high and low temperatures---or equivalently, the record high degree-days in a day. My purpose is to check if the "design temperature" commonly quoted for my area (-10F) differs from the record average temperature, and if so, by how much.

Where can I find this information? Many thanks,

Alan R. Mercurio_3

you might want to try this?

Degree Day Systems

Your friend in the industry,
Alan R. Mercurio

www.oiltechtalk.com

Plumbob

Nothing of interest there. I want to know the degree-day record in my area. Thanks,

Dave Palmer_3

try

the local airport,they usually have it

don_52

nws chicago

> It is easy to find, on the net, the record low

> temperature for my area (Chicago). But that's not

> particularly useful for heating purposes, because

> the record was probably reached for only a few

> minutes in th middle of the night. Maybe the day

> that had the all-time record low of (say) -27F

> also had a high temperature of +23F; who

> knows.

>

> I want to find the record low value for

> the average of the area's daily high and low

> temperatures---or equivalently, the record high

> degree-days in a day. My purpose is to check if

> the "design temperature" commonly quoted for my

> area (-10F) differs from the record average

> temperature, and if so, by how much.

>

> Where can

> I find this information? Many thanks,

don_52

nws chicago

> It is easy to find, on the net, the record low

> temperature for my area (Chicago). But that's not

> particularly useful for heating purposes, because

> the record was probably reached for only a few

> minutes in th middle of the night. Maybe the day

> that had the all-time record low of (say) -27F

> also had a high temperature of +23F; who

> knows.

>

> I want to find the record low value for

> the average of the area's daily high and low

> temperatures---or equivalently, the record high

> degree-days in a day. My purpose is to check if

> the "design temperature" commonly quoted for my

> area (-10F) differs from the record average

> temperature, and if so, by how much.

>

> Where can

> I find this information? Many thanks,

don_52

nws chicago

Mr. Kalia,

try this,

http://www.crh.noaa.gov/lot/climate.php

daily's/ monthly's / extreme's
with min / max / mean and hdd's

hope this help's

cheers

don_52

nws chicago

Mr. Kalia,

try this,

http://www.crh.noaa.gov/lot/climate.php

daily's/ monthly's / extreme's
with min / max / mean and hdd's

hope this help's

cheers

Mijola

DD Information

Maybe this will help


http://www.erh.noaa.gov/box/dailystns.shtml

Regards,

Ed Carey

.

so close...

Yep, they have mean and HDD data (same thing, adds up to 65) for 1998-2004. Very close, thanks for the link, but it doesn't tell me what the historical extreme HDD is.

They also have a table of extremes, but not mean/HDD, only max/min extremes.

.

Thanks, but see my comment above. This data is for 1997 and later. Nothing here tells me what the extreme HDD is since they started keeping records. I know the record minimum is -27, but that may not have been the record HDD.

.

Sure, I can find record highs and lows in the paper, but not record degree-days.

Constantin

Extreme HDD?

I think I understand where you are trying to go... get extreme HDD data to best account for the heating plant needs, right?

However, I would stick to using the 99th percentile low temperature to calculate the max. HDD, due to the thermal flywheel effect of buildings. Most of them aren't open to the world (like my house under renovation is right now) and thus will need some time to cool down beyond the 68°F that the entire interior has been brought up to.

Last winter we had a couple of days of -15°F weather. That's what I designed to since that was the lowest ongoing temperature I can remember, and lower than the -10°F or so that (IIRC) HVAC-Calc suggested as a design temp in Boston. On the other hand, the author of Hvac-Calc also recommends upsizing a heating system 15% beyond the calculated heat loss need, just to be on the safe side...

don_52

We'll build our own....

Mr. Kalia wrote,

"Very close, thanks for the link, but it doesn't tell me what the historical extreme HDD is".

and;

"They also have a table of extremes, but not mean/HDD, only max/min extremes".

Mr. K, you should be able to calculate the "extreme hdd"
data set from what is presented, like this:

max_temp + min_temp / 2 = mean_temp ( avg. )

65 - mean_temp = hdd

Sorry there is no data table that shows exactly what you
want, I haven't seen one here;

http://www.cpc.ncep.noaa.gov/

or here;

http://www.noaa.gov/pastweather.html

design temp is;

normal_low_avg + extreme_low_avg * [ -x% ] + normal_low_avg = design_day_temp

66.6% is -10.2 degrees for Chicago, I can't remember
what ASHRAE Region 6 says, book buried in basement.

A cursory look at the data yields a ratio of 1.071:1.000,
take the hdd data from the normal "daily's and multiply
it by 1.071 and you'll get close to an "average" extreme
low hdd for a month.

If you'd like, click reply and email me directly, I'll
help you build a spreadsheet formatted the way you'd
like to see it.

in chicago, regards, don

.

> Mr. Kalia wrote,

>

> "Very close, thanks for the

> link, but it doesn't tell me what the historical

> extreme HDD is".

>

> and;

>

> "They also have a

> table of extremes, but not mean/HDD, only max/min

> extremes".

>

> Mr. K, you should be able to

> calculate the "extreme hdd" data set from what

> is presented, like this:

>

> max_temp + min_temp /

> 2 = mean_temp ( avg. )

>

> 65 - mean_temp =

> hdd

>

> Sorry there is no data table that shows

> exactly what you want, I haven't seen one

> here;

>

> http://www.cpc.ncep.noaa.gov/

>

> or

> here;

>

> http://www.noaa.gov/pastweather.html

>

> d

> esign temp is;

>

> normal_low_avg +

> extreme_low_avg * [ -x% ] + normal_low_avg =

> design_day_temp

>

> 66.6% is -10.2 degrees for

> Chicago, I can't remember what ASHRAE Region 6

> says, book buried in basement.

>

> A cursory look

> at the data yields a ratio of 1.071:1.000, take

> the hdd data from the normal "daily's and

> multiply it by 1.071 and you'll get close to an

> "average" extreme low hdd for a month.

>

> If

> you'd like, click reply and email me directly,

> I'll help you build a spreadsheet formatted the

> way you'd like to see it.

>

> in chicago,

> regards, don

JwKVT

JwKVT

I was able to find the NOAA HDD information for the last 116years for my state by doing a google search for NOAA HDD Vermont