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General Weather/Earth Sciences Topics => Weather Conditions Discussion => Topic started by: ch8ch on December 27, 2017, 07:16:34 AM

Title: 3 different station brands....same results at night
Post by: ch8ch on December 27, 2017, 07:16:34 AM
I started the hobby in and around 2008. I've had 3 different station models. At night in calm conditions I can be 4-8 degrees lower than surrounding stations (wunderground). If there's a slight breeze or cloudy conditions I'm right on. Their algorithm was removing me from the map at night at one point. I emailed them (2-3 times) this fact and they have stopped removing me. Now I have a ""Goldstar" status. This has been an issue with all of the brands. Daytime temps are right on no problem with radiation or anything. This is the backyard.
 
In the front of the house I have 2 different older models of indoor/outdoor thermometer units. They are more in line at night with the surrounding weather stations.
Right now my backyard station is reading 2 degrees. An older backyard station is at 4. A mile away a station is 6. The guy across town is at 9. My front porch units say 9.
I dont want to name the brands because I don't want to start a war over that.
I will tack it up to an anomaly or maybe i have ghosts in my backyard.  :twisted:
I guess I'm soliciting opinions or thoughts or maybe someone else has seen this.
thank you
Title: Re: 3 different station brands....same results at night
Post by: miraculon on December 27, 2017, 09:28:34 AM
I have seen as much a 12°F difference between my location and the local airport. I am lower in elevation by some 50-60 feet and the cold air can "dam" up against the escarpment. The local Marina also shows several degrees difference at times. I have redundant sensors, two of which are in fan-aspirated housings and agree very well with each other.

I suspect that you are seeing micro-climate effects due to topographic variations. This is very normal. I would not expect to see stations agreeing in temperature a mile away unless conditions are uniform across a large area.

Greg H.
Title: Re: 3 different station brands....same results at night
Post by: countdemonet on December 27, 2017, 01:52:43 PM
I'm a new shooter here and with my first station. I'm having the same problems being kicked off the Wunderground (WU) map for quality. After a few days of study I find myself 3-5 degrees warmer than my neighboring stations and occasionally even more. After comparing to three other sensors on my own site I find all in close agreement. I finally have attributed this to having warm lake water close by. Even though it's iced over, it must be giving up heat to the local area. I've appealed to WU for some relief from their quality alogrithm.   
Title: Re: 3 different station brands....same results at night
Post by: ch8ch on December 28, 2017, 08:46:01 AM
It took 3 emails to wunderground to fix that....I explained pretty much what I've said here and ever since last year sometime they stopped flagging me and I got a Goldstar designation to boot. My issue must be elevation. I'm only 10 feet below the closest station but that 10 feet makes a difference on some nights. Last night with a slight breeze I'm right on with the neighbors.
Title: Re: 3 different station brands....same results at night
Post by: ggsteve on December 28, 2017, 12:42:36 PM
I am in a valley and surrounded by hills on 3 sides.  My temps often drop 5-10* lower than other nearby stations, so WU drops me a lot.  I am also using two different station brands that usually agree withing a degree or two.  I've had the gold star for a couple of years, but it doesn't mean much.  A few weeks ago a station in Mass was reporting 40 degrees higher than every other local station, probably brought in the house.  It still had it's gold star!