famartin Posted October 20, 2012 Share Posted October 20, 2012 Also as I was saying october is only following recent trends if it is only around 1 or so above normal and snow cover is above normal that those 2 factors will bode well for snow and near average temps and please notice on the local nws site that west chester is around 4 or more degrees cooler than philly consistently this year. PHL average highs: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 45.9 48.8 61.7 65.7 77.2 83.4 90.8 86.9 78.3 West Chester average highs: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 43.7 48.5 60.5 64.0 75.7 81.7 89.2 85.6 77.8 Difference: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 -2.2 -0.3 -1.2 -1.7 -1.5 -1.7 -1.6 -1.3 -0.5 That difference is not a big deal given that from what I can find, the West Chester station is almost 400 feet above sea level and PHL is just above sea level. Given these values, I would not expect there to be a sensor/instrument problem. PHL average lows: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 29.9 33.1 42.7 45.4 59.2 63.7 72.7 70.4 62.3 West Chester average lows: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 23.3 25.4 35.9 37.0 54.5 56.0 65.7 63.1 53.6 Difference: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 -6.6 -7.7 -6.8 -8.4 -4.7 -7.7 -7.0 -7.3 -8.7 The main difference is at night, and that's almost certainly caused by the urban heat island. Link to comment Share on other sites More sharing options...
tombo82685 Posted October 20, 2012 Share Posted October 20, 2012 PHL average highs: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 45.9 48.8 61.7 65.7 77.2 83.4 90.8 86.9 78.3 West Chester average highs: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 43.7 48.5 60.5 64.0 75.7 81.7 89.2 85.6 77.8 Difference: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 -2.2 -0.3 -1.2 -1.7 -1.5 -1.7 -1.6 -1.3 -0.5 That difference is not a big deal given that from what I can find, the West Chester station is almost 400 feet above sea level and PHL is just above sea level. Given these values, I would not expect there to be a sensor/instrument problem. PHL average lows: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 29.9 33.1 42.7 45.4 59.2 63.7 72.7 70.4 62.3 West Chester average lows: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 23.3 25.4 35.9 37.0 54.5 56.0 65.7 63.1 53.6 Difference: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 -6.6 -7.7 -6.8 -8.4 -4.7 -7.7 -7.0 -7.3 -8.7 The main difference is at night, and that's almost certainly caused by the urban heat island. ray where did you find this information? Do they have other sites? Link to comment Share on other sites More sharing options...
Bliz299 Posted October 20, 2012 Share Posted October 20, 2012 ray where did you find this information? Do they have other sites? I think I can be of help here. It appears it came from the Mt. Holly website. From the home page, Climate>Local>NOWData. There are other sites listed for which data is available. The data Ray listed is there. If he obtained it elsewhere I'm sure he'll let us know. Link to comment Share on other sites More sharing options...
Mitchell Gaines Posted October 20, 2012 Share Posted October 20, 2012 I like the signs for a cooler weather pattern to close out Oct . Modeling starting to pick up on it. Personal viewpoint of course. Link to comment Share on other sites More sharing options...
Rainshadow Posted October 20, 2012 Author Share Posted October 20, 2012 Adam, Mark was nice to run a regression equation first incorporating the snow cover with the other variables (Oct mins, Nov maxes and Julian Day of the first cold snap) and second as a stand alone variable. When incorporating all of the other factors (from Mark): I plugged in the snow cover data. The good news was that the sign of the variable's coefficient in the resultant equation was negative, meaning more snow cover was associated with lower temperatures, but the bad news was that the coefficient was not significantly different from zero, meaning there was about a 30 percent chance that randomly generated data would have yielded a signal at least as strong. Now on Siberian (Eurasian Snow cover alone) and I'm paraphrasing which means I may have got some of this wrong. The 95% confidence interval is all on the negative side, it explains 12% of the variance and the co-efficient of the equation is -0.51. The conclusion that he derived is that the Siberian (Eurasian) snow coverage is a stand alone variable. Basically you can follow that or you could follow the Oct mins/Nov maxes (for PHL). The latter by being colder/warmer should be affected by the snow coverage being greater/lesser. Incorporating it with the other factors would rank it 4th, so it hardly moves the needle. Thus nothing wrong with Eurasian snow cover, but locally you get just as much if not more with following the Oct/Nov couplet. This is me: Depending on how the last 10 days transpire here and over there we may be in "mode conflict", e.g. greater snow coverage, warm October, so it will be interesting to see first if this occurs and then who wins this winter. Perfect progging the GFS (ok ha ha ha) it looks as though snow coverage should get filled in on the western edge north of 60N with not much advancement south and losses in China. Link to comment Share on other sites More sharing options...
easternsnowman Posted October 20, 2012 Share Posted October 20, 2012 PHL average highs: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 45.9 48.8 61.7 65.7 77.2 83.4 90.8 86.9 78.3 West Chester average highs: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 43.7 48.5 60.5 64.0 75.7 81.7 89.2 85.6 77.8 Difference: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 -2.2 -0.3 -1.2 -1.7 -1.5 -1.7 -1.6 -1.3 -0.5 That difference is not a big deal given that from what I can find, the West Chester station is almost 400 feet above sea level and PHL is just above sea level. Given these values, I would not expect there to be a sensor/instrument problem. PHL average lows: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 29.9 33.1 42.7 45.4 59.2 63.7 72.7 70.4 62.3 West Chester average lows: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 23.3 25.4 35.9 37.0 54.5 56.0 65.7 63.1 53.6 Difference: YEAR JAN. FEB. MAR. APR. MAY. JUN. JUL. AUG. SEP. 2012 -6.6 -7.7 -6.8 -8.4 -4.7 -7.7 -7.0 -7.3 -8.7 The main difference is at night, and that's almost certainly caused by the urban heat island. Yes I think rhat is the big diffrence and I've had people mention that to me. Link to comment Share on other sites More sharing options...
am19psu Posted October 22, 2012 Share Posted October 22, 2012 Adam, Mark was nice to run a regression equation first incorporating the snow cover with the other variables (Oct mins, Nov maxes and Julian Day of the first cold snap) and second as a stand alone variable. When incorporating all of the other factors (from Mark): I plugged in the snow cover data. The good news was that the sign of the variable's coefficient in the resultant equation was negative, meaning more snow cover was associated with lower temperatures, but the bad news was that the coefficient was not significantly different from zero, meaning there was about a 30 percent chance that randomly generated data would have yielded a signal at least as strong. Now on Siberian (Eurasian Snow cover alone) and I'm paraphrasing which means I may have got some of this wrong. The 95% confidence interval is all on the negative side, it explains 12% of the variance and the co-efficient of the equation is -0.51. The conclusion that he derived is that the Siberian (Eurasian) snow coverage is a stand alone variable. Basically you can follow that or you could follow the Oct mins/Nov maxes (for PHL). The latter by being colder/warmer should be affected by the snow coverage being greater/lesser. Incorporating it with the other factors would rank it 4th, so it hardly moves the needle. Thus nothing wrong with Eurasian snow cover, but locally you get just as much if not more with following the Oct/Nov couplet. This is me: Depending on how the last 10 days transpire here and over there we may be in "mode conflict", e.g. greater snow coverage, warm October, so it will be interesting to see first if this occurs and then who wins this winter. Perfect progging the GFS (ok ha ha ha) it looks as though snow coverage should get filled in on the western edge north of 60N with not much advancement south and losses in China. Thanks, Tony, and thanks to Mark for running the numbers. I'm not terribly surprised that the two factors are independent of one another. What are the main factors that affect PHL temps in Oct/Nov and what do they mean for the future? I know the Siberia snow cover predicts the winter AO state (due to its effect on the polar vortex) and I doubt that PHL temps are predicting the future state of the AO. It's fun trying to piece it all together. Link to comment Share on other sites More sharing options...
Rainshadow Posted October 22, 2012 Author Share Posted October 22, 2012 Thanks, Tony, and thanks to Mark for running the numbers. I'm not terribly surprised that the two factors are independent of one another. What are the main factors that affect PHL temps in Oct/Nov and what do they mean for the future? I know the Siberia snow cover predicts the winter AO state (due to its effect on the polar vortex) and I doubt that PHL temps are predicting the future state of the AO. It's fun trying to piece it all together. Yes, the PHL temps are the results, not the cause. I think there is an ONI component that he uses too, but I don't see it in his seasonal write-up. Link to comment Share on other sites More sharing options...
am19psu Posted October 22, 2012 Share Posted October 22, 2012 Yes, the PHL temps are the results, not the cause. I think there is an ONI component that he uses too, but I don't see it in his seasonal write-up. Right. I'm sure the PHL temps are a proxy for some other atmospheric variable (ENSO? NAO?), but I can't imagine that it's the AO, since the winter time AO is driven by completely different things than what would be driving PHL temps. Link to comment Share on other sites More sharing options...
Rainshadow Posted October 23, 2012 Author Share Posted October 23, 2012 I don't see how we don't average above normal snow coverage for the month of October. Talking about chicken vs the egg, that's the one since 1967 that has worked the best, 9 of 14 nino Octobers have had it. Link to comment Share on other sites More sharing options...
Rainshadow Posted October 27, 2012 Author Share Posted October 27, 2012 Some good news on the winter. No way Eurasian snow cover is going to be below average for October, so our chances for a snowier than current average winter has tripled from about 18% to about 50%. Because of 95-96 and 09-10, since the 1967 satellite data 29 winters have had snowfall below our PHL cur normal and 15 above. Yes there are plenty right around 20". Link to comment Share on other sites More sharing options...
Rainshadow Posted November 1, 2012 Author Share Posted November 1, 2012 PHL October temp was 59.4F (warm) and October Eurasian snow cover has to be above normal. I don't know how many times this juxtaposition has happened since 1967 and how many near el nino are involved. When things calm down a bit more, I'll post additional info. Meanwhile keep an eye on Nov temps. Have found no correlation with November snow cover. Link to comment Share on other sites More sharing options...
easternsnowman Posted November 1, 2012 Share Posted November 1, 2012 West Chester and most of Chester county came in at least 4 degrees below philly which has been the case most of the last year. I believe temp wise West Chester came in around average for October. Link to comment Share on other sites More sharing options...
famartin Posted November 1, 2012 Share Posted November 1, 2012 West Chester and most of Chester county came in at least 4 degrees below philly which has been the case most of the last year. I believe temp wise West Chester came in around average for October. Actually they were +1.4. Not as substantial as PHL's +1.9, but not that different either. Link to comment Share on other sites More sharing options...
easternsnowman Posted November 1, 2012 Share Posted November 1, 2012 Actually they were +1.4. Not as substantial as PHL's +1.9, but not that different either. I think the high minimum temps were responsible in both cases. Was'nt august and september near average in west chester? Link to comment Share on other sites More sharing options...
famartin Posted November 1, 2012 Share Posted November 1, 2012 I think the high minimum temps were responsible in both cases. Was'nt august and september near average in west chester? August was +1.5, September was +1.3 0.6 (sorry read the wrong row) Link to comment Share on other sites More sharing options...
easternsnowman Posted November 2, 2012 Share Posted November 2, 2012 August was +1.5, September was +1.3 0.6 (sorry read the wrong row) Thanks for the info. It's interesting to see in the big cities how much more of an impact climate change has, compared to smaller locales. Link to comment Share on other sites More sharing options...
tombo82685 Posted November 11, 2012 Share Posted November 11, 2012 Tony, any correlation to above normal oct snowfall and below normal november temps? I think we have a solid shot at below normal november. Link to comment Share on other sites More sharing options...
phlwx Posted November 14, 2012 Share Posted November 14, 2012 How winters fare with a cool to cold November. Used 59 as the threshold (that's 1.5 above modern average) for October temps and 46.5 or colder for November (which is 0.6 below our current norms). Link to comment Share on other sites More sharing options...
Animal Posted November 17, 2012 Share Posted November 17, 2012 any update for November Tony? I recall last year you took us up to this month and gave us the cold dose of reality for Winter. Br, darkstar Link to comment Share on other sites More sharing options...
Rainshadow Posted November 29, 2012 Author Share Posted November 29, 2012 any update for November Tony? I recall last year you took us up to this month and gave us the cold dose of reality for Winter. Br, darkstar Darkstar, Link to comment Share on other sites More sharing options...
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