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We might be cloudy and cool a lot of the time, but we're a great place to live if you want to avoid death by natural disaster. Good for growing crops, too.
NY would definitely feel more humid in summer because the summer air masses often come from the south (the tropics), so humidity and esp dew points are much higher in NYC (London is way too far north to often see tropical air advected that far north.).
These airmasses affect the UK, with mT being the most common with the prevailing SW'lies. In spring and early summer cT becomes more common with the Azores high, though recent poor summers have been caused by mP air.
These airmasses affect the UK, with mT being the most common with the prevailing SW'lies. In spring and early summer cT becomes more common with the Azores high, though recent poor summers have been caused by mP air.
I think the map you are showing might be confusing you a bit:
The prevailing wind direction and what is known as the MRSW (mean resultant surface wind) is nearly always out of the west over the UK (as well as much of Western Europe). This wind direction brings mild mP air masses (Maritime Polar) that have have their source from the central Atlantic Ocean between latitudes 40 to 50 north. These air masses are temperate in summer time (ave temp 50 to 65 F) and cool in the winter time (ave temp 35 to 50 F).
The only source region for cT tropical air masses near the UK/western Europe is off NW Africa (about 1600 miles to the south. However, since the Atlantic high creates winds in a northerly direction off the upper NW African coast (and cool water down the coast) it’s rare for NW Europe to see hot air masses. On occasion, cT air masses do reach SE Spain, and southern Italy.
This map shows the ave summer wind direction and streamlines of pressure (winds normally follow the lines of equal pressure):
These airmasses affect the UK, with mT being the most common with the prevailing SW'lies. In spring and early summer cT becomes more common with the Azores high, though recent poor summers have been caused by mP air.
That mT air you are showing comes across waters much cooler than the air masses we get over the very warm gulf of mexico or gulf stream along the east coast of the US. The water off of Portugal is quite cold. More like California water than the gulf stream waters we have. The image below is from August 3, 2012.
The wind from the Med would def be warmer with higher dewpoints, but how often does the UK get those winds? Your average high for the month of July is no higher than 74.3F(23.5C) at Heathrow, so it cannot be frequent. London is one of the warmest parts of the UK.
The wind from the Med would def be warmer with higher dewpoints, but how often does the UK get those winds? Your average high for the month of July is no higher than 74.3F(23.5C) at Heathrow, so it cannot be frequent. London is one of the warmest parts of the UK.
Feb to May is usually dominated by high pressure and southerly winds are most common at this time of year. They are usually dry, not humid. July and August are more dominated by SW winds like the rest of the year.
Annual wind direction at Heathrow
SW - 21%
W - 19%
S - 16%
N - 11%
NE - 10%
NW - 9%
E - 8%
SE - 6%
Feb to May is usually dominated by high pressure and southerly winds are most common at this time of year. They are usually dry, not humid. July and August are more dominated by SW winds like the rest of the year.
Again, I think you might be a bit confused:
First, the Feb to May time period in the UK is rarely (if ever) dominated high pressure. What it is (often) dominated by is “blocking”: High pressure (H) centered out in the Atlantic Ocean to the SW of the UK near 40 to 45 north acts to block rain-bringing weather disturbances moving in the normal westerly direction toward the British Isles and NW Europe. This is why there is often fewer rainy/cloudy days from Feb though early May in the UK (though often it is far from sunny). The block breaks down in June typically.
Next, rarely, (if ever) are there true south winds (S) or even south-southwest (SSW) winds in the British Isles.Much of the time the winds over the UK have a strong westerly component. These westerly winds over the UK are what brings the air masses to the UK much of the year. The “source regions” of these air masses is what gives them their character (temp/dew point/humidity…etc.).
In the case of the British Isles and much of lowland NW Europe, the source region of these air masses in the cool high latitude Atlantic Ocean: This oceanic air is often cool, humid, mild (even in winter), and there is much stratus. This is in sharp contrast to dry cT (Continental tropical)….cP (Continental Polar)…and bitter cold and dry cA (Continental Arctic) air masses.
Getting back to the point I mentioned…this is totally different than NYC, which OFTEN experiences cP air mass control in winter. Thus, dry, bright, and cold weather with very low humidity occurs far more often in NYC in winter than in London. This was my point - that London, while warmer than NYC in winter, often sees worse weather with the humid air and overcast skies. NYC on the other hand sees much cold/dry air and bright weather in winter.
Finally, the most tropical air masses with the highest humidity/dew points, termed mT (Maritime tropical), or mE (Maritime Equatorial), has its source region in the wet low latitude tropics and tropical oceans between 0 and 25 North/South. Locations like the tropical rainforests of the Amazon, the Congo, Southeast Asia, and the adjacent oceans like the Caribbean Sea/Gulf of Mexico/tropical Atlantic…etc are source regions. These regions are far too distant to ever reach NW Europe.
This is a good map of prevailing source regions of world air masses averaged over the year. You can see quite clearly that mP air masses is right next to the UK much of the year. In contrast, NYC has source regions for both cold/dry cP and humid mT air masses – and the seasonal change in wind directions is what creates the rather sharp differences between the summer vs winter weather in NYC:
Are you really lecturing someone about the climate of their own country? Perhaps you should stick to boring people with essays on the Floridian climate, or how comparable climates in the US are superior to their Australian counterparts. We really don't need your wisdom or insight on the UK's climate too.
Are you really lecturing someone about the climate of their own country? Perhaps you should stick to boring people with essays on the Floridian climate.
Science is science....sorry if that doesn't fit your agenda.
Perhaps you should find web sites less complicated for you.
What agenda do I have? Elaborate please, I'm genuinely interested. I await with trepidation.
To me, it just appears that you were making a big deal out of something minute, and being incredibly pedantic by suggesting that B87 is under the illusion that the UK's dominant wind direction is not SW, simply because he suggested that the UK is influenced by other wind directions too, even if they are far less frequent on average, and that periods of cloudy high pressure and stratocumulus-dominated cold, dry continental winds occur with a certain level of frequency too, and have been more common in recent years. Take it from someone who has lived here all of their life - while SW winds usually rule the roost, extended periods of dry, continental winds, moisture-laden NWly winds, and hot southerlies, are by no means uncommon, and you would do well to read B87's post again - he suggests cT becomes more common, not that it is the ruling wind direction at any point of the year.
Last edited by dunno what to put here; 05-22-2013 at 08:33 AM..
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