knocker

Thanks for that. I see what you mean. This forum takes a bit of getting used too. I would delete it but don't seem to have a delete button at the moment.

Being new on here I'm not sure exactly how to go about this but I'm sure I'll be pointed in the right direction.:unsure: The morning started off with touch of small Cu. that has developed somewhat since in line with isolated showers forecast. I'll chuck in the Camborne midnight sounding for good measure.I'm not sure they still do an 0600.

Is there any interest ion this sort of info? DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1255 AM CDT FRI SEP 17 2010 VALID 171200Z - 181200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM NRN KS INTO SRN AND ERN NEB...CNTRL IA AND NWRN MO... ...SYNOPSIS... A LARGE LOW AMPLITUDE UPPER LOW/TROUGH WILL MOVE EWD ACROSS CNTRL CA AND ACROSS THE NRN PLAINS TODAY...FLATTENING THE UPPER RIDGE ACROSS THE CNTRL PLAINS BY LATE IN THE DAY. MEANWHILE...AN UPPER SHORTWAVE TROUGH AND SURFACE LOW WILL BE PRESENT NEAR THE NEW ENGLAND COAST...BUT WILL DEPART DURING THE DAY WITH RELATIVELY COOL AIR ALOFT IN A NWLY FLOW REGIME EXTENDING SWD INTO THE APPALACHIANS. AT THE SURFACE...A COLD FRONT WILL SLOW ACROSS SRN NEB...WITH SLY BRINGS BRINGING MID TO UPPER 60S F DEWPOINTS NWD AS LOW PRESSURE DEVELOPS NEAR THE KS/CO BORDER. ...NRN KS/SRN NEB INTO IA AND NRN MO... SURFACE WINDS WILL INCREASE OUT OF THE SOUTH TODAY AS LOW PRESSURE DEEPENS OVER WRN KS/ERN CO. DEWPOINTS IN THE 65-70 F RANGE WILL SPREAD NWD INTO KS AND SRN NEB WHERE A SURFACE FRONT WILL STALL THIS AFTERNOON AS WINDS N OF THE FRONT VEER TO ELY. STRONG HEATING AND PRESENCE OF RELATIVELY STEEP MID TO UPPER TROPOSPHERIC LAPSE RATES WILL RESULT IN STRONG INSTABILITY WITH FORECAST SOUNDINGS INDICATING MUCAPE IN EXCESS OF 3000 J/KG. STORMS ARE EXPECTED TO INITIATE FIRST ACROSS NWRN KS/SWRN NEB WHERE LOW LEVEL LAPSE RATES WILL BE DRY ADIABATIC. THESE STORMS MAY BE HIGH BASED INITIALLY...BUT WILL LIKELY FORM INTO SUPERCELLS AS THEY SHIFT EWD ACROSS NRN KS/SRN NEB. EFFECTIVE BULK SHEAR ON THE ORDER OF 40 KTS BY 00Z AS WELL AS LOW LEVEL VEERING IMMEDIATELY NEAR THE SURFACE BOUNDARY WILL FAVOR SUPERCELLS CAPABLE OF VERY LARGE HAIL...DAMAGING WINDS AND ISOLATED TORNADOES. TRAINING SUPERCELLS...SOME BOWING AND PRODUCING DAMAGING WIND...SHOULD PERSIST ALONG THE BOUNDARY THROUGH THE PERIOD AS A SWLY LOW LEVEL JET ENHANCES LIFT AND MAINTAINS INFLOW. ACTIVITY SHOULD EVENTUALLY MERGE INTO ONE OR MORE SMALL MCS'S WITH MAINLY A DAMAGING WIND AND HEAVY RAIN THREAT INTO IA AND NWRN MO BY THE END OF THE PERIOD. ...WRN NC/NWRN SC... A WEAK THERMAL TROUGH ALOFT WILL EXTEND SWD ACROSS THE APPALACHIANS WHICH WILL COMBINE WITH STRONG HEATING TO PRODUCE MARGINAL INSTABILITY WITH STEEP LOW LEVEL LAPSE RATE PROFILES. ALTHOUGH MOISTURE WILL BE LIMITED...AT LEAST ISOLATED CONVECTION IS LIKELY TO FORM OVER THE HIGHER TERRAIN OF WRN NC INTO NWRN SC. NWLY FLOW ALOFT ALONG WITH THE RELATIVELY DRY BOUNDARY LAYER PROFILES INDICATE A THREAT OF A FEW STRONG TO POSSIBLY SEVERE WIND GUSTS BY LATE AFTERNOON. ----------------------------------- DAY 2 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1252 AM CDT FRI SEP 17 2010 VALID 181200Z - 191200Z ...NO SVR TSTM AREAS FORECAST... ...SYNOPSIS... ONLY MODEST CHANGES TO THE LARGE-SCALE FLOW FIELD ALOFT ARE EXPECTED THIS PERIOD...WITH A LARGE RIDGE TO PREVAIL ACROSS THE CENTRAL AND SRN PORTIONS OF THE U.S. AND A LOW/TROUGH REMAINING OFF THE W COAST. BELT OF VERY FAST FLOW WILL REMAIN ACROSS THE U.S./CANADA BORDER AREA...AS A DEEP VORTEX SHIFTS ACROSS THE NRN ONTARIO/NRN QUEBEC REGION. AT THE SURFACE...A COLD FRONT ASSOCIATED WITH THE CANADIAN UPPER LOW WILL MOVE EWD ACROSS QUEBEC AND THE GREAT LAKES REGION...WHILE SHIFTING MORE SLOWLY SEWD ACROSS THE MIDWEST/OH VALLEY REGION. THE FRONT SHOULD MAKE EVEN SLOWER PROGRESS SWD ACROSS THE CENTRAL PLAINS...POSSIBLY BECOMING QUASI-STATIONARY DURING THE SECOND HALF OF THE PERIOD. ...SRN IA/NRN MO/NRN IL AND VICINITY... AN AREA OF MAINLY ELEVATED THUNDERSTORMS SHOULD BE ONGOING ACROSS THIS REGION AT THE START OF THE PERIOD...NEAR THE NOSE OF A VEERING SWLY LOW-LEVEL JET. WHILE SOME HEATING/DESTABILIZATION IS FORECAST S OF THE SSEWD-MOVING COLD FRONT...WEAK ASCENT NEAR AND S OF THE INCREASINGLY ANAFRONTAL-TYPE BOUNDARY SUGGESTS THAT MOST CONVECTION WILL REMAIN ELEVATED N OF THE SURFACE FRONT. CONVECTION SHOULD LINGER THROUGH THE DAY...LIKELY EXPANDING/INCREASING AGAIN DURING THE EVENING AS THE LOW-LEVEL JET REDEVELOPS. WITH RELATIVELY WEAK ELEVATED INSTABILITY EXPECTED DUE TO PERSISTENT CONVECTION AND WITH STRONGER FLOW ALOFT REMAINING N OF THIS REGION...SEVERE THREAT SHOULD REMAIN LIMITED. HOWEVER...WILL INTRODUCE LOW PROBABILITY /5%/ SEVERE AREA GIVEN SOME POTENTIAL FOR HAIL.

I suspect your second suggestion is nearer the mark as being part of the ray doesn't seem quite right. Edit. Thinking about it again they could be partially superimposed with the distance from the camera of the two a fair bit different. Difficult to say really.

Funny enough that's roughly where the "Fish Palace" used to be in the 19th century where they brought the pilchards. Today only a small section above the little slipway remains.

Just to add a bit more to this. http://www.metoffice.gov.uk/climate/uk/interesting/oct2008/index.html The infrared image shows the wintry storm that brought extensive flooding to the Ottery St Mary area of East Devon. Courtesy Dundee Satellite Receiving Station.

I don't know whether it applies where you are but they often live down old mine shafts. Many around here and this is an example of an old "bat castle". They are slightly more refined now.

Around the UK- Marine air and sea surface temperatures (SST) have been rising at a similar rate to land air temperature, but with strong regional variations. Since the 1980s the rate of rise has been about 0.2-0.6 ºC per decade.Warming has been faster in the English Channel and southern North Sea than within Scottish continental shelf waters.At great risk I'll link the website. It does contain some rather useful info. ( IMHO of course) http://www.mccip.org.uk/annual-report-card/2007-2008/marine-environment/temperature.aspx

In the 19th century Portreath could be taken as a microcosm of the Cornish mining industry. It is now a holiday town although some remnants of the past still exist. A quick explanation just to clarify a couple of the photos. The small round hut at the end of the pier, known as "Monkey Island", was built to protect men on lookout duty when the jetty was extended in 1824. There is no public access to this jetty. The round pilots' house on the north side of the harbour was also used as a mortuary for wreck victims and others. Thus the name Deadman’s Hut. The "daymark", since it contains no light, was built around 1800 and doubled as a navigational aid and coastguards' and pilots lookout. Its local nicknames are "The Pepperpot" and "The Lighthouse".

Agreed , looks that way with strands of stratocu. underneath. I particularly liked no. 5 although they are all excellent.

And probably total cloud cover would increase and clouds at different levels have different feedbacks. I don't think I'll go there.:lol:

I'll just throw this in as a general observation from the Marine Institute of the University of Plymouth, case study 4. The other link is redundant. http://www.research.plymouth.ac.uk/marine/pages/assessing/climate.html

I agree John that it is Meteorologically fascinating about the troughs embedded in the flow and their quite localised effects. AW made a rather telling point about this that I will quote. "The revelation of the troughs in the airstream over the Fastnet fleet provides a possible cause for locally enhanced winds. However, to develop such a trough and keep it for several hours in one place, as one trough is shown to do, (diagrams are useful here-my comment), demands some more or less stationary cause which in the gathering wind field of an advancing depression is difficult to envisage. Thus I cannot as yet give a satisfactory account of what caused these troughs, but the yachts' own barometers revealed them as being there." Whether AW has resolved this problem since I know not but I imagine the opportunities for detailed research in this area are a bit thin on the ground.

The heading of this thread is The North Atlantic Current is gone. This is a subject for oceanographers I would have thought. I have no doubt ther are experts on here, and I bow to their superor knowledge, but predicting autumn and winter weather on ocean heat transfer (Gulf Stream) and reliability of the jet stream, plus interuption of the convergence zone is fraught with danger. My confidence is not high. Classic winter setups can be caused by other reasons. Why are you assuming last winter was caused by the weakening of the Gulf Stream? I asume your experts will tell you.

Well seeing most are posting websites I might as well join the club albeit the site is a few months old. I for one won't be buying any long johns. http://news.bbc.co.uk/1/hi/8589512.stm

I don't know if this is any good to you. I was going to post it in reply to another post that I can't find at the moment. I don't know of any mechanism that can cause cold deep water to warm and rise. Of course near the coasts the water will be shallow in comparison. Anyway it'sa fairly interesting diagram.

Some reminders of China Clay mining.

Neither the formal report of the Fastnet Race inquiry nor the official meteorological analysis seemed to explain all that had happened during this disaster. In particular, although it was a very severe storm, it wasn’t exceptional, so why did this unprecedented carnage take place? Was there something going on that was slipping under the radar? Very many experienced competitors stated that the wind strength was not unusual, but that the sea conditions were the most dangerous they had ever experienced. Most of the damage done to the yachts was due to the waves and not to wind. Perhaps the clue lay here. Allan Watts, a meteorologist particularly concerned with small boat navigation, decided to dig a little deeper and the result of his research, Fresh Evidence on the Fastnet Storm, was published in the Journal of Navigation in 1982. For © reasons I can’t upload the article but his original description of the storm can be found in the Fastnet Race Inquiry Report and is worth a read. http://www.blur.se/i...ace-inquiry.pdf To continue. Initially Allan Watts found that there was a divergence of opinion between the Met. Office who were taking their wind speed from their charts (48-55 knots) and many competitors who were convinced that the top strength was into Force 11 (56-63 knots). How best to resolve this difference.Watts took a line of action that at the time was probably unique. He analysed the barometric records of the yachts themselves having obtained as many as possible from the competitors. The readings of the yachts were checked for accuracy whenever possible by comparing the given readings with the known values at St. Mary’s as the yachts were passing. He plotted the results along the rhumb line from Scilly to the Fastnet Rock at four synoptic hours, 1900, 2200, 0100 and 0400 BST. Something quite surprising showed up. A series of troughs in the isobars which would not be detectable from the course plot of barometric readings from the professional reporting stations in the Fastnet area. What Allan Watts called a meteorological oddity. Some of these troughs were 3 to 6mb below what otherwise might have been expected Allan Watts considers that the role of these troughs in the disaster may well have been crucial. Another major factor involved was not the average height of the waves, but the number of ‘episodic’ waves that were generated by the storm. An episodic wave is one of those normally rare waves of excessive height that may well be bred by superposition of wave trains in any storm of severe gale proportions that blow for sufficient length of time to make the proposition a probability. It would appear that in the Fastnet there may well have been dozens of these waves. Back to the troughs. The revelation of the troughs in the airstream over the Fastnet fleet provides a possible cause for locally enhanced winds. Allan Watts noted that when yachts were reporting mean winds of up to 55kts and gusts into hurricane force (64+ knots) they were mainly to be found close to the troughs. At the same time boats within a few miles were only recording winds of force 7 and, importantly, AW believes that it is this variation of speed across the wind field that caused the strange seas and contributed greatly to the disaster. Sea and wind conditions are extremely difficult to analyse but Stephens, Kirkman and Peterson have done some very pertinent work in the area. The part that is of particular importance to the Fastnet shows that when the wind speed suddenly increases the seaway follows without a significant time interval. In other words winds suddenly generated by local meteorological conditions induce immediate heightening of the sea under them-an increase that will not be experienced in surrounding parts of the wind field not subject to the local increase. Allan Watts goes on to say that analysis of waves capable of capsizing yachts in the way they were doing during the Fastnet yacht race shows that they must be very steep and that there is a fast moving ‘jet’ at the crest of the wave that is moving at perhaps twice the speed of the water in the lower part of the profile. Apparently such waves were responsible for capsizing several NOAA weather buoys between 1977-9. A couple of his main conclusions were: (i) In the troughs that developed over Fastnet the wind increased on the periphery of the trough, but there was a lowered wind speed near the axis and outside the periphery of the trough. (ii) Thus surface ‘jets’ only a few miles wide were flanked by lower wind speeds. As the seaways builds without appreciable delay, so massive waves developed along the jets, but lesser seas existed on their flanks. The transverse wind shear may therefore account for the high seas experienced by the crews of the yachts in the 1979 Fastnet storm. Refs. Watts, A., Fresh Evidence of the Fastnet Storm, Journal of Navigation, 1982. Stephens, O. J. Kirkman, K. L., & Peterson, R. S., (1981). Sailing Yacht Capsizing. Society of Naval Architects & Marine Engineering. AVHRR 13/08/79 0903UTC

I believe this was the same storm that recorded a pressure at the Ben Nevis Summit Observatory at 2030 of 784.7mb (1343m). The story of the observer tying a rope around himself to attempt to read the temps and avoid being blown away is quite amusing. Succeeded at the third attempt!

I don't know whether this is of interest, or even if it has been posted before, On Vancouver’s historic voyage around the world from 1791 to 1795, Archibald Menzies served as surgeon and naturalist. During the voyage, he kept a weather log, including in it observations of air temperature, sea-surface temperature, barometric pressure, wind direction and wind force (using terminology similar to that used by Admiral Beaufort a decade later in the first published version of his famous scale of wind force). The log is important historically, for it includes the first weather observations ever made systematically along the west coast of North America (from Mexico to Alaska), among them observations made whilst at anchor at San Francisco and Monterey. The sheets on which Menzies recorded his observations have recently been returned to the archive of the Royal Meteorological Society. The story of how they came to be in the possession of the Society in the first place will be told in this presentation. http://ams.confex.com/ams/Annual2005/techprogram/paper_83619.htm http://ams.confex.com/ams/pdfpapers/83619.pdf

Glad to see I've reminded you of the good old days John.

Thanks to those who answered my query. I've since realised that there was an article in weather on this very subject by Professor Robert Pearce, Department of Meteorology. University of Reading in 2005.. The article has been revisited by Roger K. Smith andthe latter is available online. I think I'll stick to the explanations on here as the complexities of the dynamics I freely admit are beyond me. http://www.meteo.physik.uni-muenchen.de/~roger/Publications/Weather_2005_Smith.pdf

I like that. Great detail.http://nwstatic.co.uk/forum/public/style_emoticons/<#EMO_DIR#>/good.gif

I know this is digressing slighly but why must hurricanes have eyes?