Curious weather phenomenon

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pugwash94

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A few weeks ago I was sailng along the western arm of the Solent heading for Lymington. I was beating into SW 4. The wind veered 45 degrees and the temperature rose.
The were no cumulo-nimbus and we were not close to any frontal system identifiable on the weather charts. I am aware that it is possible to have small localised frontal systems that endure for short periods but these should not produce much in the way of a temperature change but more to the point logic suggests that any marked backing wind shift should cause the temperature to drop.
Can anyone explain?
 
In answer to the various questions:

It was about 15:30, cloud cover was about 7/10, I was mid-Solent i.e. about 1.25 miles from N & S shores. Regretably I cannot recall which day it was but I looked at the synoptic chart that evening and I recall we were mid-way between High to the South and Low to the North with the lines not particularly close - and surprisingly more wind generally than I would have expected from looking at the Chart - and more than was forecast.

Unlikely to have been connected with a sea-breeze because I suspect the wind would have backed if it was (I had a land mass on either side but the larger was to the North) and in any case it was a pretty cool day which was why the rise in temperature was so marked.

The Australian example I don't think applies because the equivalent would be a backing wind.

The other thing I did not mention was that the effect persisted - I continued to head North rather than towards Lymington till I tacked again and headed direct for the Limington River and did not change until I was within the river and the wind was a reduced and affected as I went up river.

I have been trying to think and find explanation off and on since I experienced it.
 
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15.30pm, more than likely you were beating against a modified (i.e weak) sea breeze, which collapsed and allowed the regular wind to re-establish. Temperatures will rise in this location due to the prevailing wind blowing across the land mass of Purbeck and the New Forest, rather than in off the sea. Sea breezes often are failing about this time of day. A modified sea breeze will be generated where the effect is not strong enough to fully overcome an existing wind and is quite common.
 
I thought that could explain the higher wind strengths and even the very noticable wind shift but I cannot work out how a backing wind could produce such a significnt rise in temperature rather than a fall.
 
pugwash94 said:
I thought that could explain the higher wind strengths and even the very noticable wind shift but I cannot work out how a backing wind could produce such a significnt rise in temperature rather than a fall.
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OP says the wind veered 45 degrees. That would bring it offshore from the Forest, which with its sandy soils warms the air above it. The SW breeze would have been off the sea therefore noticeably cooler, particularly the cool air of a sea breeze.
 
oldharry said:
OP says the wind veered 45 degrees. That would bring it offshore from the Forest, which with its sandy soils warms the air above it. The SW breeze would have been off the sea therefore noticeably cooler, particularly the cool air of a sea breeze.
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I guess that is possible but it was a generally cool day with significant cloud cover and had been greater cloud cover during the morning and early afternoon. The veering effect would normally be the result of a cold front. Added to which warm air coming in from NW (heated by the Forest) would tend to rise up over the cooler SW from the sea.
What baffles me is that the phenomenon seems to suggest a descending column of warm air.
 
Agree a descending warm air mass would be very unusual. Warm front moving in? But that's quite a wind veer. It would be interesting to know just how the cloud cover changed. Otherwise some sort of fairly local effect, with a warm air mass encroaching an otherwise cool regime. But how? Hot and cold draughts are not uncommon round major Cumulo Nimbus, but OP says there weren't any.
 
Old Harry, if I there had been any sign of Cb I would have put it down to that. Equally if it was a warm front the wind should have backed. Hence my puzzlement and I cannot find any explanation anywhere. Incidentally I mentioned it to a couple of other skippers at the quay in Lymington who had arrived about the same time and they had noted the wind shift and the rise in temperature although they had not realised the apparent contradiction.
 
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