New Hampshire Ski Season Begins!
Bretton Woods is the first area to report 2 of 98 trails open, lifts open. To keep up to date, tune in here: https://www.skinh.com/conditions
Tsunami Warning? No, only a test
Recently browsing the web site, I saw that warnings had been posted for the Portsmouth and Rockingham areas and clicked for more details. The most unbelievable warning popped up — Tsunami Warning! Really? Immediately, the HUGE list of affected areas, starting with “Laguna Madre From the Port of Brownsville to the Arroyo Colorado” had me suspect someone accidentally spilled coffee on the Big Red Button or something. Scrolling, scrolling, scrolling finally got to the actual text, which started out: THIS_MESSAGE_IS_FOR_TEST_PURPOSES_ONLY. Whew! You coulda lead with that…
The alert was gone a moment later.
Does Anyone Really Know How Hot It Is?
(with apologies to the band Chicago)
Last summer, I was watching temperatures rise in the wicked heat, and I noticed the “feels like” temperature displayed on the weather station web site was sky-high, 108°F on a mid-90 degree day. I checked the reported “feels like” on the local sensor gateway G!100 and on the WeeWx data page, and it was only a few degrees above the plain temperature. What the heck was going on?
Well, it seems like we can’t agree on what “feels like” means. Everyone knows a 90°F day with low humidity and a little breeze is tolerable, if a little hot for us northerners. But the same 90°F with 90 humidity and still winds has everyone reaching for the A/C, a fan, and some ice water.
With the increasing frequency and intensity of the heat, vigorous occupations and sports have focused on the danger of serious heat-related injuries and fatalities. Surely, there must be some standards to apply to the situation.
Well, we like standards so much we’ve made dozens!
“Feels Like” or “Apparent Temperature” is a calculation of temperature and humidity and wind speed created in 1984. While relatively easy to calculate, this really only applies to indoor situations where solar heating is not a factor.
“Humidex” is a similar calculation more common in Canada (and was also the standard on the weather software I was using, hence the difference in values).
Wet-bulb temperature deserves a mention here, although it’s not a measure of “feels like,” but is often confused with the next one. A thermometer is wrapped in a wet cloth sock, and the temperature will differ from dry air temperature by the cooling effect of the water evaporating (absorbing its “latent heat of vaporization” if that rings bells from science classes) and can be used to calculate relative humidity with a simple mechanical device called a “sling psychrometer” and a simple lookup table. This is popular where complex or delicate instrumentation isn’t a good choice, such as the logging industry or grade-school science classes.
Wet bulb globe temperature (WBGT) is currently the most popular for calculating heat stress, the combined effects of temperature, wind, humidity and heat (solar radiation or other heat sources). It uses a dry-air temperature, a wet-bulb temperature for humidity, the temperature inside a black globe exposed to the sun or heat source, and factors in the wind for evaporative effects to create an estimate of how hot it really feels. This estimate is rapidly becoming an important guideline in sports, industry and governmental regulations.
A great article on WGBT can be found here.
Finally, we can’t forget the “RealFeel™” a trademarked and patented proprietary calculation by Accuweather.com. Using similar calculations and factors above, as well as combining special factors of their own, Accu
So, keep in mind when you hear the day is going to “feel like” that there’s a bit of disagreement on what exactly that means, and how it is measured. But, hey, be careful out there.
Misadventure, repaired
Alert weather watchers (do you guys ever take a day off??!!!??) noted that the site went a little sideways yesterday. The main thermometer thought the high and low for the day was 32°F, the winds and other basic parameters were not right, and some of the supplementary pages failed to load or generated a pageful of errors. Hopefully, it’s working better today.
A junior web operator who shall remain nameless attempted to check the web sites’ configuration files into Git and instead loaded in the entire site, including dynamically updated data files and cached files. This means Git will pretty much always report the repository is out of date, and make cloning amd redeployment a serious hazard. In fixing the issue, the problem compounded: it turns out the “git rm” command does not remove the file from git as one might suspect, but instead OBLITERATES THE WORKING FOLDER OF PRODUCTION DATA and marks the file retained in (for historical purposes), but no longer active in the repository. Removing live data and cached files while the website is running had predictably disastrous results. Management has been notified and stern lectures delivered about diddling with the live production site without making three backups while clicking your heels together.
The management wishes to apologize to anyone who just wanted to know what the weather was outside. Yesterday, you would have had to go out IRL and look for yourselves; today, you can check on your phone again.
GW1100 Antenna Placement
I’ve been doing some experiments in finding the optimal placment of the GW1100 gateway. The gateway receives radio signals from Ecowitt weather instruments in the field: anemometer, UV, light, air & soil temperature, humidity, rain as well as in-house temperatures, barometric pressure and indoor pm2.5, does a few local calculations, hosts a small set of web pages, and makes the data available over the in-house intranet. If the signals from the instruments are too weak or attenuated (by distance, metal screens, water walls or dense construction). that data is lost.
I noticed when I added the meadow soil temperature instrument (an Ecowitt WN34S) last week, that the readings were erratic, so I checked on the strength of the signal, and eventually graphed all of the signals on our in-house WeeWx web page. I first moved the GW1100 to an upstairs rear window. Anemometer signals were better, but rain and T&H outside worse. I tried a back room on the lower floor and that may turn out to be optimal. I’ll continue to test.
Signal strength is reported by the GW1100 in a scale of zero to four. and the WeeWX software graphs an average value The nearby in-house “Upstairs” and “Basement” temperature/humidity sensors (two Ecowitt WH32) always have a strong signal. The outdoor T&HP sensor (Ecowitt WH31_EP) was good when the GW1100 was in north-facing windows at the front or back of the house, but signals were poor around 1600 when I tried the upstairs placement. The anemometer (an Ecowitt WH68) has never been very strong, as it is the furthest away, and behind a metal-roofed garage. When the GW1100 was upstairs the signal appeared the strongest, but the rain gauge and outdoor T&H were notably weaker.
Alert readers (I see you out there!) will wonder why I didn’t just use the internal web pages of the GW1100 that display a “signal” column, shown above. The problem with those is that the signal strength appears to be averaged over time, and not as immediately responsive as the graphs I generated with WeeWX. Overnight, all of the signal scores caught up, and all are displaying four bars in the morning.
Fall upkeep
The autumn season turned startlingly fast with morning temperatures dropping into the 40s, so it’s time to do the upkeep and maintenance on the outside instruments before winter weather makes them inaccessible. Today, I replaced the AA battery in the anemometer. I use lithium batteries for the outdoor instruments, as they are long-lasting, and tolerate a wider range of temperatures.
Added a new Soil Temperature sensor
One of our home landscaping projects is to recover an area overrun by bittersweet vine, and we’re going to try to establish a wildflower meadow. Following instructions from the seed vendor, we were told to track the soil temperature. Ecowitt sells the WN34S soil temp probe, and it was pretty simple to power it up and get it to display on our in-house monitors.
Fixed the River Levels page
Thanks to Ken True of Saratoga-weather.org, an updated script to display river levels is in place. The NOAA has replaced a couple of older systems with inconsistent APIs and data formats with a new and improved system. Note that for the moment, you need to click to close the update message and the legend that take up half the display, but that should be temporary.
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New WX page
Today, I added the World Weather Extremes page. A reminder to be grateful you’re not THERE!
Happy CoCoRaHS anniversary!
Today marks three years since I started recording CoCoRaHS — Community Collaborative Rain, Hail and Snow network — daily observations, missing only one day so far. Today was an observation of 11 inches of snow in the field, 5.7 on the snowboard, and water equivalents of 0.69″ on the board and 1.55″ in the field measurement. That’s a lot of water!