2021 NH Summer/ SH Winter discussion thread

Back to Riga... and here the high is only 17C. I have headache all day with a front passing to the East.

Sure. 😅

Here're the final highs for Italy today:

Just had a nice t-storm this evening with lots of lightning. I didn't really get a ton of rain with it - measured 0.34 inches. Storms came in from the northeast.

It got up to 96F this afternoon. 

Might've been about 10 mins of sun here in the last 4 days. Mid level overcast again today, looks like our 19C forecast will be 15C unless something changes. Meanwhile 20C in Adelaide 

7m swells in the Swan River would be some appropriate penance.

Today's supposed to be an active weather day, NWS has 1-2" (25.4 - 50.8 mm) of rain predicted today, we'll see. I get a feeling it'll be giant FIZZAAAAAHHHHHHH. Morning low was 78 F (25.6 C), predicted high is 82 F (27.8 C) but it's already 82 F (27.8 C) with a 74 F (23.3 C) dew point as of 8 am, and the sun is starting to come out.

Quite high rain chances in all of southern FL today:

First two weeks of June 2021 in Umeå:

On the 10th I managed fixed the issue where the sun would shine directly on the sensor around 18.30-20.30, by putting a bunch of conifer twigs in the tree in that direction to make the foliage denser. Seems to have done the trick perfectly. My PWS still consistently reads 0.3'C cooler than the AP during cloudy weather - I don't know if that's a true difference due to elevation or if my sensor is calibrated too cool. Also consistently records cooler highs during sunny weather than would be expected from its more urban location - likely a combination of being in complete shade (i.e. having better shielding against radiation than even a stevenson screen) as well as a little lower sensor response time. On the 12th it rained and my PWS read almost 0.5'C cooler temps than the AP, and funny enough the DP recorded was almost 0.5'C warmer than the temp recorded. I wonder how that even happens. I suppose there could be some issues with water sticking to the radiation shield (and surrounding vegetation of course).

Averages:


(Note that I only used highs set during daytime, and from the PWS I excluded all readings between 18:00 and 21:00. I also used the 18.1'C high from my PWS as today's high at the airport (their warmest hourly reading was 17.2 but the official high hasn't been published)

Using SMHI's 20:00 day cutoff, the average high becomes 21.7'C at the airport instead. Since my PWS was erroneous around 18.30-20.30, using 20.00 as a day cut-off wasn't viable before the 10th, and neither was 24h means. But now since that problem is fixed, I'll be able to use the same cutoff point as SMHI uses, and I'll be able to use 24h mean values


Looking at the graph and comparing the hourly values, it does seem like the sea breeze tends to hit the airport sooner and more intensely on average. The airport still usually records warmer highs despite of that because of more rapid response time.

^ Yes, I did a more thorough analysis which I posted in the PWS vs AP thread, but I'll leave a short summary here as well to not leave this thread with a dead discussion. The PWS is surrounded by a small group of trees which can affect the low by a little bit (although probably not more than maybe 0.3'C at most). The average low at the Uni Patio was a little bit lower than my PWS (which can be explained in large part by a more rapid temperature change response). The Uni station is indeed located on a patio about 3m above the ground, which obviously is going to add a fair bit to the lows, upwards of 0.5-1.0'C in extreme cases I can imagine. However, topographically the Uni station is at a disadvantage because it's right next to hills and a frost prone valley, so I would imagine that a "perfect" station located where my PWS is would record warmer lows than a "perfect" station located where the uni station is.

Edit: Here are some topography maps showing this.
Uni patio vs PWS location:


Clearly, if the Uni station and my PWS were both in Stevenson screens on an empty grass lawn, but in the same location as they are now, the PWS would have an advantage when it comes to mild lows, and I'm not sure the fact that the uni station is located on a 3m tall rooftop patio is enough for the lows to for sure be milder than the PWS.