An illustration of why its good to camp mid slope instead of in a valley

[peakbagger]

Berlin NH's morning temp -18 F. Temp at Gorham Randolph line +11 F. As the crow flies about 5 miles between the two points (might be 10 miles if the reporting site is Berlin airport which is actually in Milan). Difference in elevation about 500' with Berlin in the valley and my place mid slope. The difference is usually the most with a clear night.

I tend to get more wind at my place as its a south facing slope, so the prevailing westerly wind is more prominent, but with some shelter to the west, it gets quite pleasant with a bit of sun out of the wind.

Something to be said for studying the local microclimate!

 

[hikingmaineac]

Yeah, but who wants to sleep like this?

 

[MindlessMariachi]

interesting - i will take any info you can give on the mini climate of that region. when i worked at Sunday River, I noticed that if I got the Bethel, ME temp from weather.gov, they actually gave me the temp in Berlin, and it was always a good bit colder than at Sunday River. I've done winter camping trips in the Evans Notch area, and when looking at the weather.gov figures after the trip, I always find myself saying, 'there's no way it was that cold!' (sometimes I take the temp from Fryeburg ME, which can be a lot different, in either direction, and average the two!). Anyway, Berlin Airport seems like it's probably the Antarctica of New Hampshire.

 

[Brambor]

Bruno

It sure keeps the water out but make sure you're wearing a Velcro suit.

 

[peakbagger]

I am not a meterologist nor do I play one one TV, but heres my SWAG

The Berlin airport (in Milan) is on a broad open valley right next to the androscoggin river. There is high terrain to the west and mostly flat area to the east. Speculation on my part is that the terrain to the west tends to deflect wind away from the surface of the valley which reduces atmospheric mixing. The Androscoggin valley north of Milan drains eastern NH to the Canadian border via Aziscohos Lake and Parmachenee via the Maglalloway River and the western half of maine via the Kennebago/ Rangeley watersheds. Both of these watersheds have large lakes which have radiational cooling. Cold air sinks and hot air rises, so I expect that the cold air from the lakes flows down the Androscoggin valley to the first national weather reporting site at the airport in Milan and thats why Berlin gets tagged as the cold spot. When I was involved with emission permitting, the term the experts used was "valley drainage".

I expect that if there was a NWS site in Errol and it was situated in similiar terrain as Milan than that would be a cold spot.

Sunday River's weather is not going be as cold as its on the north side of the mountains that form the Androscoggin River valley. There is also a fairly sharp turn in the river in Gorham and another one in bethel (where it flows north) which probably shuts down the cold air flow from the north country. Sunday River is effectively sheltered from the valley drainage from the Androscoggin watershed by the Mahoosuc Range. The areas upslope of Sunday river are all forested with no big impoundments or fields which appear to be more effective for radiation on clear nights.

By the way, when I worked in the mill in Berlin right on the river, the temp readings for Milan were usually right on for the mill. Its one of the only places that had to worry about freezing a steam coil heater.

 

[weatherman]

Could 'na said it better myself. Then again, I'm not a met either. Try Weather Underground to find some of those unofficial cold spots too.

With no wind and clear skies, the ravine near our house next to a reservoir is sometimes as cold as Loveland Pass (6300 feet higher and 70 miles west). With a well-mixed atmosphere and downsloping wind, sometimes 40+ degrees warmer!

 

[TomD]

One of the strange things in the Tahoe area in NorCal is that Truckee, the little town by Donner Pass, always seems to be colder than the rest of the area. I have never figured out why, but it can be colder there than at the neighboring ski resorts like Squaw Valley.

 

[woodstrider]

why it's good to camp mid-slope

Well, when it's cold, low spots, from slight dedressions to valleys, are cold-sinks. It always pays to be particular about where you thrown down camp. I have camped in a slight depression and slept cold when the little tiny knoll nearby was better. This is also a good idea to prevent your camp from flooding in a rain storm.

Colder air is denser then warm air and so is heavier. Therefore it will seek the lower ground with lighter, warmer air on top.`

But if you are on the big peaks and camp on the slope, look for a protected camp- like in a copse of trees (as opposed to an exposed slope)- if you can find it.

Big mountains create their own winds, like in the evening- when there is a change in temperature, with cooled air rushing down slope. These winds can be very fierce, but I have experienced them dying down after awhile. That is, if the wind is caused by temp. changes- as opposed to, say, a high wind system.

 

[una_dogger]

I am not a meterologist nor do I play one one TV, but heres my SWAG

.

Did someone say Weatherman Swag?? Is that, like, when you have your own rain guage or somethin'??

 

[peakbagger]

SWAG - Scientific Wild Ass Guess.

 

[DougPaul]

SWAG - Scientific Wild Ass Guess.

I hadn't heard of SWAG, just WAG. sounds to me like the S is just to dress the pig up.

Doug

 

[Vermonster]

<snip>

I expect that if there was a NWS site in Errol and it was situated in similiar terrain as Milan than that would be a cold spot.
<end snip>
.

There is a temp gauge at the Errol Dam and a second at the Errol "International" airport. You can access this data: http://amazon.nws.noaa.gov/hads/charts/NH.html

Comparing 7am temperatures (F):
Today
Errol Dam: 32.0
Errol Airport: 31.1
Berlin Airport (Milan): 32

Yesterday
Errol Dam: -6.7
Errol Airport: -3.1
Berlin Airport (Milan): -14

On the coldest mornings, it's usually a tossup between Berlin/Milan and Whitefield for lowest NH (non-summit) temp. Both these are airport locations so I suspect radiational cooling plays a substantial role.