Weather Appreciation

[Glacier]

Sometimes a pictures is worth a 1000 words, so I give you a global map. Remember that the magnitude of seasonal and diurnal temperature changes can be large or small, depending on:

1. Latitude
2. Elevation
3. Topography
4. Proximity to the moderating influences of nearby oceans or large lakes.

And a map zoomed in the U.S.A. (no such map exists for Canada)...

The change temperature is related to the net radiation, and can be expressed with the simple formula

• net radiation = incoming solar (mostly visible light) - outgoing IR (infrared)

If the net radiation > 0, surface warms ( 6 AM - 3-5 PM); if the net radiation < 0, surface cools (3-5 PM - 6 AM)

This also explains why the warmest part of the year is in July/August, not on 21 June during the summer solstice.

[Glacier]

We still have to wait another couple of days before Environment Canada releases the May 2013 summary, but suffice to say, May was wetter than normal around here. More precisely, the second half of May was wetter than normal. From what I see so far, the second have of the month was 50 times wetter than the first half.

While we await, the results, let us review how much snow we had in 2012. For the 6th time in 7 years, 2012 was snowier than average. with the 2010 decade a third of way through, the decade is shaping up to be the snowiest decade since the 1970s.

For what it's worth, the 1950s was the snowiest decade on record while the 1940s was the least snowiest decade. Records began in the 1870s. 1971 was the snowiest year on record while the 1941 was the least snowiest decade.

2012 was much snowier than average in the Interior, but the coast saw less snow than average. Peachland (the only Okanagan weather station that actually recorded snow last year) had 126 cm, which was the 4th snowiest year on record (30 years on record). This is 32 cm more than average. It was also the 4th snowiest year on record in Creston where records stretch back 94 years. The 219 cm they had was 74 cm above average. Merritt was the only interior location with lower than average snowfall, recording only 66 cm, or 16 cm below average.

At the other end of the spectrum, Victoria had their 11th least snowiest year on record (68 years worth of data).

In absolute terms, the snowiest place with complete records in 2012 was Goldstream River (464 cm), while the least snowy place in BC was Victoria (14 cm). Whistler Roundhouse did have more snow (1376 cm of snow), but that station had missing days. It is quite common for places to go all year without snowfall. 2005 was the last time this has happened in BC.

[Glacier]

The May 2013 summary is now posted. Here are the highlights for May and the Spring:

Hottest temperatures in Canada.

1. Ashcroft, BC = 34.6°C
2. McLeese Lake, BC = 34°C
   Oliver, BC = 34°C
   Petawawa, ON = 34°C

...
93. Vernon, BC = 30.8
124. Kelowna, BC =30.5

Winfield, BC = 30.5

142. Penticton = 30.3

Every single place in BC was warmer than average in May with the exception of extreme northwest. When I say extreme northwest, I'm not kidding. Pleasant Camp (0.5 degrees below normal) was the only spot in the entire province below normal. The Okanagan was about 1.3 degrees warmer than average.
Hottest average temperature in Canada:

1. Ashcroft, BC = 16.8°C
2. Windsor, ON = 16.7°C
3. Lytton, BC = 16.3°C
4. Lillooet, BC = 16.2°C
   Osoyoos, BC = 16.2°C

The driest places in Canada are pretty much always in the far north. In our part of the world, we were much wetter than normal. Osoyoos was the one exception, were they only had half of the normal precipitation. At the other end of the spectrum, Princeton was more than 200% of normal.

Driest Places in BC last month:

1. Osoyoos = 16.8 mm
2. Atlin = 16.9 mm
3. Fort Nelson = 24.6 mm
4. Vanderhoof = 28.1 mm
5. Sandspit = 29.4 mm

The most recent May was one of those rare exceptions where the wettest places in Canada were not in BC. This was because Quebec was very wet while the usual suspects on the BC Coast were drier than normal.

Wettest places in BC:

1. Village of Zeballos = 261 mm
2. Boat Bluff (a lighthouse) = 241 mm
3. Tahsis Village = 204 mm
4. Nootka Lighthouse = 197 mm
5. North Vancouver Seymour Hatchery = 188 mm

The Okanagan was unseasonably wet outside of Osoyoos. Vernon had over 80 mm, and Kelowna was near 60 mm.

7 places in BC had snowfall last month:

1. Sikanni Chief = 38 cm
2. Fort Nelson = 14 cm
3. Sparwood = 6 cm
4. Hedley NP Mine = 5.6 cm
5. Fernie = 4 cm
6. 100 Mile House = 0.6 cm
7. Atlin = 0.1 cm

Environment Canada defines Spring as March through May. Osoyoos was by far the driest place in BC during the most recent season with only 42 mm. This is the first time since 1964 that Osoyoos has had the province's driest Spring! Osoyoos' total was less than half that of second place Fort Nelson. Kelowna was 5th with 127 mm of precipitation.

[Glacier]

Of no surprise to any of you, the BC Coast gets the least amount of snowfall in Canada. Many places down there have gone all year without any of the white stuff. Closer to home, some of the warmer, drier spots of the BC interior don't get very much snowfall either. The other place in Canada that also doesn't get much snow is the far north. Eureka, Nunuvut, the coldest place in Canada, only gets 58 cm/year of snow. This is less snowfall than Penticton!

1941 was the all time lowest snowfall year, marking the first and only time that less than 10 cm of snow fell in the Okanagan. Oliver only recorded 6.1 cm that year, while Lillooet recorded a mere 3.2 cm! Okanagan Centre only had 11.9 cm of snowfall, and Kelowna had 17.9 cm. Not bad when you consider the fact that Kelowna gets about 90 cm in an average year (+/- depending on which part of the city are measuring it).

Below is a list of the least snowiest places in the BC Interior based on average annual snowfall. Notice that Lytton gets 3 times the snowfall of Lillooet and Spences Bridge even though it really isn't that far away from either of those two communities. There is a bit of +/- involved here because different time frames yield different results, but the general trend holds.

1. Lillooet = 31 cm (21 years of data)
2. Spences Bridge = 38 cm (29 years of data)
3. Ashcroft = 48 cm (48 years of data)
4. Osoyoos = 51 cm (35 years of data)
5. Oliver = 51 cm (40 years of data)
6. Keremeos = 61 cm (59 years of data)
7. Naramata = 61 cm (27 years of data)
8. Riske Creek = 65 cm (20 years of data)
9. Penticton = 69 cm (65 years of data)
10. Nicola Lake = 75 cm (32 years of data)
11. Summerland = 76 cm (79 years of data)
12. Kamloops = 77 cm (71 years of data)
13. Kelowna = 78 cm (31 years of data)
14. Okanagan Centre = 78 cm (55 years of data)
15. Merritt = 80 cm (37 years of data)
16. Alexis Creek = 81 cm (28 years of data)
17. Shalalth = 84 cm (32 years of data)
18. Williams Lake = 89 cm (21 years of data)
19. Vernon = 89 cm (21 years of data)
20. Westwold = 94 cm (74 years of data)
21. Peachland = 94 cm (30 years of data)
22. Winfield = 96 cm (31 years of data)
23. Moha = 99 cm (23 years of data)
24. Lytton = 101 cm (33 years of data)
25. Kelowna Airport = 101 cm (32 years of data)

[Glacier]

Today's UV index reached 8.0 at 11:41 this morning, which is the highest reading of the year. No wonder my neck got so burnt today!

[Glacier]

In Canada snowfall as a percentage of annual precipitation makes up anywhere from less than 0.5% at the Quatsino Lighthouse to 90% in the extreme far north (Alert, Nunavut).

For most of BC snowfall makes up a significant percentage of the overall precipitation - up to 80% at Old Glory Mountain. Most places are under 50%, however.

McCulloch Lake gets 53% of its precipitation from snow, which is about the same as Whitehorse and Yellowknife. The Brenda, Hedley Nickelpate, and Highland Valley mines get even higher percentages of precipitation as snow.

Closer to home, Kelowna, Vernon, Salmon Arm, Armstrong, and Sicamous receives about 30% of their precipitation in terms of snow. This is about the same as Calgary. Snowfall accounts for less as you go further down the Okanagan valley. Osoyoos only gets 17% of its precipitation as snow. By comparison, Toronto only gets about 15% of their precipitation as snow. Lillooet is the only place in the BC interior lower than Osoyoos. They receive about 10% from the white stuff.

[Lady tehMa]

I'm really tired of all this rain . . . is this an abnormally wet spring? When can we expect some better weather (based on previous history). I've got a nasty head cold right now, and I'm tired of being cold and feeling miserable.

[zzontar]

This inconsistent weather is getting way too consistent.

[Glacier]

I'm really tired of all this rain . . . is this an abnormally wet spring? When can we expect some better weather (based on previous history). I've got a nasty head cold right now, and I'm tired of being cold and feeling miserable.

Rain is the standard fare this time of year. We generally don't get hot, dry summer weather until we approach the 10th of July in our part of the world. By contrast, Alaska gets very nice weather this time of year, which is why the average June temperature in Kelowna is only 0.5 degrees higher than Fairbanks, Alaska! [1] [2]

Speaking of Alaska, Alaska and parts of the Yukon are getting a heatwave right now. 35 degrees in Alaska this week. Old Crow, in the northern Yukon is forecast to hit 31 today.

Closer to home, June is the wettest month of the year in Vernon, Kelowna, Penticton, and most other places in the southern interior. In addition, May is the second wettest month of the year in many places including Penticton and Kelowna.

Osoyoos is a little different where May is the wettest month. Vernon is another exception were May is the third wettest month (November is second).

So, yes it is wetter than normal this May-June, but it is not that abnormal for it to be quite wet this time of year. June is the only month were Kelowna averages more than 40 mm. Not bad when you consider that June is a short month.

The climate has been getting wetter in BC since things bottomed out in 1929. 2012 was the 10th wettest year on record ( 118th driest year on record). I've posted this before, just in case you missed it, here is how precipitation has changed over time in our province...

[Lady tehMa]

thx Glacier

I may have seen that before but honestly my brain is not at 100% right now (stupid cold). July 10th, eh? I'll keep holding on . . .

[Donald G]

I am glad that we have people who have a well above average interest in what the weather was like in the past and may or will be in the future. The view on a thousand or ten thousand year basis, rather than our memories of the weather over one generation, is needed to gain an appreciation of the HUGE part World Weather Patters have played in everything from food production, migrating deserts, past frequently occurring diseases, epidemics and pandemics, population bottle necks with world wide human die-offs, evolutionary patterns adopted by humans as most advantageous including the changes in skin coloration that has erroneously cause us to look like and think that we are not all from one evolutionary entity that walked out of Africa, into Europe, about 150,000 years ago.

That our local weather patterns have changed notably in the past and will change notably in the future is an absolute given. We know what they have changed from, especially in the last 2,000 years because of the information gained from the Greenland Glacier ice core. We can guess at what they will change to as a result of Global Warming but, only those with an intense interest in our local weather patterns, as they evolve, will be in the best position to tell us how people in the Okanagan can best prepare for life over the next 100 or 1000 years.

[Lady tehMa]

Are the scientists able to extrapolate enough data to give us a climatogy timeline?

I know there was some kind of "mini ice-age" in the dark ages, and there have been ruins of cities discovered in many places underwater, off the coast of Britain etc.

It would be interesting to see a timeline that incorporates all that . . .

[Glacier]

The longest continuous temperature record in the world (without the use of proxies) is in Central England. The Hadley Centre Central England Temperature (HadCET) dataset goes all the way back to 1659!



Closer to home, records began in BC in 1873, but there weren't many stations before about 1900. I have constructed the temperature, precipitation, and snowfall record for Britich Columbia back to 1900.

Warmest Year = 1998 (1.5 degrees above normal)

Coldest Year = 1916 (1.8 degrees below normal)

Wettest Year = 1997 (159% of normal)

Driest Year = 1929 (57% of normal)

Snowiest Year = 1971 (190% of normal)

Least Snowy Year = 2010 (39% of normal)

The trend line is the 10 year running average.

[Glacier]

Are we heading toward another 1950? What do you think?

[Glacier]

Puerto Lopez, Colombia: the new wettest inhabited place in the world?

Data recently provided by IDEAM (Instituto de Hidrología, Meteorología y Estudios Ambientales), the Colombian national meteorological service (in English the ‘Institute of Hydrology, Meteorology, and Environmental Studies’) indicates that one of their official sites named Puerto Lopez de Micay in the Cauca Department, Pacifica Region has an average annual rainfall of 12,892.4 mm (507.57”) for the period of April 1960-February 2012 (the last month for which I have data, although the site is still in operation). There are, however, significant gaps in the record since 1960, especially during the 1968-1979 period. In spite of this there do exist complete records for 31 years in all (through 2011) and the record is only missing four months since 1991. Taking the average for those 31 complete years of data the annual average actually comes out a bit higher at 13,466.3 mm (530.17”). The wettest year was 1984 with an astonishing 23,818 mm (937.72”) and the driest with 6,195 mm (243.90”) in 1980 (both years with complete data sets). Almost as incredible are the number of days of measurable precipitation that totaled 353 days in 1984 and 355 days in 1985 (when 19,444 mm/765.51”) were recorded. Virtually two years of daily rainfall. The precipitation falls more or less evenly over the course of the year ranging from 899 mm (35.39”) in February to 1197 mm (47.13”) in May. The wettest single month on record was August 1984 when 3015 mm (118.70”) was measured. This is not a particularly impressive figure given the site’s annual average accumulation and thus illustrates how persistent and even the rainfall is month to month.



Puerto Lopez is a small town (the population is stated as 25,000 in Wikipedia, although this probably encompasses a regional area as well) located on the San Juan de Micay River in southwestern Colombia. The elevation of the rain gauge is given as 80 meters (265 feet) above mean sea level and its coordinates are 2° 50’ N, 77° 14’ W. Deep moisture from the Pacific condenses against a high mountain chain about 65 kilometers (40 miles) east of Lopez, the highest peak being Mt. Munchique rising to 3012 m (11,858 feet).

Ironically, for years the site of Lloro, Colombia in the Choco Department of northwestern Colombia has often been referenced by numerous publications, including WMO official reports, as perhaps being the wettest location on earth. This was based upon a study published in 1992 by a Mr. Jesus Eslava from the University of Bogota. He researched a site known as the Lloro Granja Agricola (Lloro Agricultural Farm) where an average of 12,717 mm (500.67”) was measured between 1952-1989. This site, however, was not an official IDEAM location, unlike Puerto Lopez. The actual town of Lloro has an average of only 7,559 mm (297.60”) for the 1971-2000 POR. So the Colombian towns Quibdo and Tutunendo are actually considerably wetter than Lloro (with annual average precipitations of 10,749 mm/423.19” and 11,394 mm/448.58” respectively).



Mawsynram and Cherrapunji, India

Currently, the official wettest site in the world (for which there is data) is Mawsynram, Meghalaya State, India with an annual average precipitation of 11,872 mm (467.40”) according to the WMO (World Meteorological Organization) Global Weather and Climate Extremes committee. This figure was based on an unknown 38-year POR. More recent POR’s have shown that the figure may be a bit higher today: from 1998 to 2010 the average was 12,700.5 mm (500.02”). Nearby Cherrapunji (which also considers itself the wettest place on the planet) averaged 11,542 mm (454.41”) for this same 1998-2010 POR.