Rainshadow Posted June 1, 2011 Share Posted June 1, 2011 IN SPITE OF ANOTHER WET MARCH AND A LA NINA IN GENERAL LAST WINTER, BOTH APRIL AND MAY WERE UNSEASONABLY WARM AGAIN FOR THE THIRD CONSECUTIVE SPRING. SINCE 1872, THIS COMBINATION HAS OCCURRED ONLY TWENTY TIMES, BUT NOW EIGHT TIMES SINCE 1990. BY DEFINITION UNSEASONABLY COOL...NORMAL...UNSEASONABLY WARM MONTHS ARE DIVIDED INTO THIRDS. THIS IS ONLY THE SECOND TIME THAT THIS HAS HAPPENED COMING OUT OF A LA NINA WINTER. SO OUR ANALOG LIST FOR THIS UPCOMING SUMMER IS EXTREMELY EXTREMELY SHORT. THE FOLLOWING IS THE ONE AND ONLY PREVIOUS SUMMER WHICH FOLLOWED A WARM SPRING EMERGING FROM LA NINA. PLEASE NOTE BECAUSE THIS SAMPLE SIZE CAN NOT GET MUCH SMALLER THAN THIS, THE MARGIN FOR ERROR IS GREATER THAN AVERAGE. YEAR JUNE AVG JULY AVG AUGUST AVG SUMMER AVG SUMMER PCPN 2001 75.2 75.4 79.9 76.8 8.00 AVG (OF ONE) 75.2 75.4 79.9 76.8 8.00 1971-2000 NML 72.3 77.6 76.3 75.4 11.50 THE OFFICIAL CPC OUTLOOK FOR THE SUMMER IS FOR EQUAL CHANCES OF IT IT BEING EITHER WARMER OR COOLER THAN NORMAL AND EITHER WETTER OR DRIER THAN NORMAL. When Mark finalizes his regression outlook (which is also hot), I'll post it. Link to comment Share on other sites More sharing options...
am19psu Posted June 1, 2011 Share Posted June 1, 2011 Confidence Interval: (-∞, ∞) Link to comment Share on other sites More sharing options...
JCT777 Posted June 1, 2011 Share Posted June 1, 2011 Confidence Interval: (-∞, ∞) Ha! Well, I'm getting the A/C fixed in my car tomorrow in preparation for the hot weather in the next few months. Link to comment Share on other sites More sharing options...
Rainshadow Posted June 1, 2011 Author Share Posted June 1, 2011 Confidence Interval: (-∞, ∞) More like Mr. Blutarsky's GPA 0.00 Link to comment Share on other sites More sharing options...
lab94 Posted June 1, 2011 Share Posted June 1, 2011 More like Mr. Blutarsky's GPA 0.00 LOL Love it. Link to comment Share on other sites More sharing options...
Quakertown needs snow Posted June 1, 2011 Share Posted June 1, 2011 Link to comment Share on other sites More sharing options...
Isotherm Posted June 1, 2011 Share Posted June 1, 2011 Tony, good luck with the outlook, and interesting conclusions. I did a similar analysis of years which featured a warm April/May in NYC over the past 40-50 years and only came up with about 12 years. Correcting for the -PDO, +AMO signals we have in place, all of the remaining summers were warmer than normal in our region. I like an anomalously mild June, followed by a near/slightly warm July, and cooler August, overall warmer than normal (2008 and 1999 were my top analogs, of course the latter was a torch). So we'll see what happens; if I bust, I think it'll be for not going hot enough! You may be in a decent place with 2001 as an analog. Link to comment Share on other sites More sharing options...
famartin Posted June 1, 2011 Share Posted June 1, 2011 More like Mr. Blutarsky's GPA 0.00 Link to comment Share on other sites More sharing options...
ptb127 Posted June 2, 2011 Share Posted June 2, 2011 I guess I may be the only one that looks forward to warm(hot)/humid summer, especially coming out of cold winter. Link to comment Share on other sites More sharing options...
Rainshadow Posted June 2, 2011 Author Share Posted June 2, 2011 Tony, good luck with the outlook, and interesting conclusions. I did a similar analysis of years which featured a warm April/May in NYC over the past 40-50 years and only came up with about 12 years. Correcting for the -PDO, +AMO signals we have in place, all of the remaining summers were warmer than normal in our region. I like an anomalously mild June, followed by a near/slightly warm July, and cooler August, overall warmer than normal (2008 and 1999 were my top analogs, of course the latter was a torch). So we'll see what happens; if I bust, I think it'll be for not going hot enough! You may be in a decent place with 2001 as an analog. Tom, Thanks, but I hope I'm wrong; have not been a big fan of hot weather since I graduated college. I've already have the thunderstorm rainshadow going in full force. I'm adding Mark's info now and he's even hotter. Link to comment Share on other sites More sharing options...
Rainshadow Posted June 2, 2011 Author Share Posted June 2, 2011 Summer (June through August), 2011 Final Temperature Forecast for Philadelphia International Airport (PHL) .............The forecast mean.................67% confidence..........90% confidence .............summer temperature is:..........interval is:...................interval is: .............77.3....................................76.2 – 78.4.................75.5 – 79.1 The forecast value is given in degrees Fahrenheit. The normal summer temperature at PHL is 75.4 degrees. Summer is defined as meteorological summer, i.e., the months of June through August. The above forecast is from a multiple linear regression equation that was derived from data from 1966 through 2010 that came from PHL. It was found that the combination of the Julian date of the first occurrence of 90 degrees or higher, the Julian date of the first heat wave of the season, the February through April Oceanic Nino Index (or ONI, an indication of the strength of the recent El Nino or La Nina), the March through May ONI, and the mean April minimum temperature explains approximately 51 percent of the variance in the mean summer temperature. The technique results in a specific forecast value and associated confidence intervals. So, the forecast of the mean summer temperature is 77.3 degrees; there is a 67% chance that the actual mean summer temperature will fall between 76.2 and 78.4 degrees, and there is a 90% chance that the actual mean summer temperature will fall between 75.5 and 79.1 degrees. Link to comment Share on other sites More sharing options...
easternsnowman Posted June 2, 2011 Share Posted June 2, 2011 Springs and summers are getting warmer in philly. I think in relation to recent summers I would consider this normal. For philly 90 will soon be the norm instead of hot. Link to comment Share on other sites More sharing options...
NaoPos Posted June 2, 2011 Share Posted June 2, 2011 I think it has to do with the urban heat island effect. We're sampling small time frames ( in relation to thousands of years) ... we might be going through a hot cycle. but im sure this stirs the debate on global warming and won't belong in here. Link to comment Share on other sites More sharing options...
Riptide Posted June 2, 2011 Share Posted June 2, 2011 Only one analog could capture the dryness of this summer...2001. My rain gauge has only recorded 15" of QPF and the year is almost 50 % complete. Link to comment Share on other sites More sharing options...
famartin Posted June 2, 2011 Share Posted June 2, 2011 Only one analog could capture the dryness of this summer...2001. My rain gauge has only recorded 15" of QPF and the year is almost 50 % complete. That's not that far from normal. Normal for Cape May through May is only 17.85", so you're 16% below average. Much wetter up north... 21.76" measured at my parents' in Ewing. PS: QPF = Quantitative Precipitation Forecast. Link to comment Share on other sites More sharing options...
easternsnowman Posted June 3, 2011 Share Posted June 3, 2011 The summer of 2001 was exactly normal (1971-2000) for Wilmington De and if you throw in September it was below normal. Of all the east coast cities philly is probably warming up the fastest, the burbs are usually cooler because we have lower night time minimum temps. Link to comment Share on other sites More sharing options...
ptb127 Posted June 3, 2011 Share Posted June 3, 2011 12z GFS comes in A LOT warmer... highs close to 90 mid-week with rising humidity levels again. Link to comment Share on other sites More sharing options...
phlwx Posted June 4, 2011 Share Posted June 4, 2011 Springs and summers are getting warmer in philly. I think in relation to recent summers I would consider this normal. For philly 90 will soon be the norm instead of hot. The average high in mid/late July is 87 in Philly. 90 in July isn't as big a deal as 90 in May is. Link to comment Share on other sites More sharing options...
phlwx Posted June 4, 2011 Share Posted June 4, 2011 I think it has to do with the urban heat island effect. The lows @ PHL are warming faster than the highs...UHI is a definite factor in the "warming" that Philly is seeing but I'll stop on the whole climate change thing before it opens a pandora's box. Link to comment Share on other sites More sharing options...
am19psu Posted June 4, 2011 Share Posted June 4, 2011 The lows @ PHL are warming faster than the highs...UHI is a definite factor in the "warming" that Philly is seeing but I'll stop on the whole climate change thing before it opens a pandora's box. I don't even know if it UHI so much as increased dewpoints. It's something I've noticed the last few years over a lot of the eastern 1/3 of the US (even cool 2009 had elevated lows), but I think it has as much to do with a warmer than normal GoM/Coastal Atlantic SSTs than climate change. Link to comment Share on other sites More sharing options...
Rainshadow Posted June 4, 2011 Author Share Posted June 4, 2011 I don't even know if it UHI so much as increased dewpoints. It's something I've noticed the last few years over a lot of the eastern 1/3 of the US (even cool 2009 had elevated lows), but I think it has as much to do with a warmer than normal GoM/Coastal Atlantic SSTs than climate change. Good point. Even our local SSTA are already above normal. Link to comment Share on other sites More sharing options...
OHSnow Posted June 4, 2011 Share Posted June 4, 2011 I'm thinking 2010 may be a pretty good analog for this summer too. Kind of scary though considering it was the hottest summer on record in 12 states and the District of Columbia. I don't know about 2001 though. June 2001 was cooler than normal for most of the midwest and southeast, and those areas look to be above normal this June (based on current conditions, computer model forecasts, and the monthly outlook from NOAA). Link to comment Share on other sites More sharing options...
Isotherm Posted June 4, 2011 Share Posted June 4, 2011 I don't even know if it UHI so much as increased dewpoints. It's something I've noticed the last few years over a lot of the eastern 1/3 of the US (even cool 2009 had elevated lows), but I think it has as much to do with a warmer than normal GoM/Coastal Atlantic SSTs than climate change. Strongly agree, much more related to the warm AMO, which allows dews to be higher in the Eastern US. Link to comment Share on other sites More sharing options...
Rainshadow Posted June 5, 2011 Author Share Posted June 5, 2011 I'm thinking 2010 may be a pretty good analog for this summer too. Kind of scary though considering it was the hottest summer on record in 12 states and the District of Columbia. I don't know about 2001 though. June 2001 was cooler than normal for most of the midwest and southeast, and those areas look to be above normal this June (based on current conditions, computer model forecasts, and the monthly outlook from NOAA). 2001 would not have been used as a midwest summer analog based on hprcc, it doesn't appear May would have ranked in the top third. This 2001 analog is intended for PHL area use only. Link to comment Share on other sites More sharing options...
Maximum lawman Posted June 7, 2011 Share Posted June 7, 2011 Summer (June through August), 2011 Final Temperature Forecast for Philadelphia International Airport (PHL) .............The forecast mean.................67% confidence..........90% confidence .............summer temperature is:..........interval is:...................interval is: .............77.3....................................76.2 – 78.4.................75.5 – 79.1 The forecast value is given in degrees Fahrenheit. The normal summer temperature at PHL is 75.4 degrees. Summer is defined as meteorological summer, i.e., the months of June through August. The above forecast is from a multiple linear regression equation that was derived from data from 1966 through 2010 that came from PHL. It was found that the combination of the Julian date of the first occurrence of 90 degrees or higher, the Julian date of the first heat wave of the season, the February through April Oceanic Nino Index (or ONI, an indication of the strength of the recent El Nino or La Nina), the March through May ONI, and the mean April minimum temperature explains approximately 51 percent of the variance in the mean summer temperature. The technique results in a specific forecast value and associated confidence intervals. So, the forecast of the mean summer temperature is 77.3 degrees; there is a 67% chance that the actual mean summer temperature will fall between 76.2 and 78.4 degrees, and there is a 90% chance that the actual mean summer temperature will fall between 75.5 and 79.1 degrees. Don't mean to nitpick, but I have some questions about this model. I would worry about multicollinearity since the two ONI indicators have two of three months in common - what does the model look like if you drop one? Same concern with the two heat dates, since the first 90 degree day often coincides with the first heat wave. Again, what happens if you drop one? What's the explained variance then? Also, a 90% confidence interval is a rather odd statistic, makes me wonder if the 95 interval includes the mean? Link to comment Share on other sites More sharing options...
easternsnowman Posted June 7, 2011 Share Posted June 7, 2011 i'm not big on models or analogs, it's better to go by trends and indices...also remember no 2 years are alike, especially these days. Link to comment Share on other sites More sharing options...
Voyager Posted June 8, 2011 Share Posted June 8, 2011 I guess I may be the only one that looks forward to warm(hot)/humid summer, especially coming out of cold winter. No, not really.... Link to comment Share on other sites More sharing options...
Rainshadow Posted June 8, 2011 Author Share Posted June 8, 2011 i'm not big on models or analogs, it's better to go by trends and indices...also remember no 2 years are alike, especially these days. Conceptual models and pattern recognition are basically a form of analogs a foundation of forecasting, without it how would anyone forecast whether its a day or month? Link to comment Share on other sites More sharing options...
Rainshadow Posted June 8, 2011 Author Share Posted June 8, 2011 Don't mean to nitpick, but I have some questions about this model. I would worry about multicollinearity since the two ONI indicators have two of three months in common - what does the model look like if you drop one? Same concern with the two heat dates, since the first 90 degree day often coincides with the first heat wave. Again, what happens if you drop one? What's the explained variance then? Also, a 90% confidence interval is a rather odd statistic, makes me wonder if the 95 interval includes the mean? I'm not the statistics person, if you want to ask Mark, I can 'pm you his e-mail address. Link to comment Share on other sites More sharing options...
easternsnowman Posted June 8, 2011 Share Posted June 8, 2011 Conceptual models and pattern recognition are basically a form of analogs a foundation of forecasting, without it how would anyone forecast whether its a day or month? I'm just saying alot of times they are wrong, but forecasting the weather no matter what method is not 100%. Link to comment Share on other sites More sharing options...
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