PrinceFrederickWx Posted December 1, 2014 Share Posted December 1, 2014 Nov. 2014 tied for 16th coldest at 43.4 degrees, along with 1875 and 1954. 2014 finished just 0.2 degrees colder than 2013 (which ranked 19th coldest) but 0.5 degrees warmer than 2012 (which ranked 11th coldest). Its fairly impressive (to me, least) that we've had three top 20 coldest Novembers in a row. The prospect of having the longest period of consecutive Novembers without snow also didn't happen, with the 0.3 inches on the 26th. But... we're now back in the running for top 10 coldest calendar year. This was tied for the 7th coldest Jan 1 - Nov 30 period ever at BWI. Link to comment Share on other sites More sharing options...
PrinceFrederickWx Posted December 9, 2014 Share Posted December 9, 2014 I did some math and calculated that BWI needs to have an average monthly temp of 34.9 (-1.8 departure) to stay in the top 10 coldest. This would actually be a tie for 8th as spots 8-10 are all tied (1875, 1886 and 1907). We are currently at +1.6, but its still possible, especially if later in the month does turn cold. If it happens, this would be the coldest calendar year since 1967. Link to comment Share on other sites More sharing options...
PrinceFrederickWx Posted December 27, 2014 Share Posted December 27, 2014 I did some math and calculated that BWI needs to have an average monthly temp of 34.9 (-1.8 departure) to stay in the top 10 coldest. This would actually be a tie for 8th as spots 8-10 are all tied (1875, 1886 and 1907). We are currently at +1.6, but its still possible, especially if later in the month does turn cold. If it happens, this would be the coldest calendar year since 1967. Well this sure ain't happening now lol Link to comment Share on other sites More sharing options...
RodneyS Posted December 31, 2014 Share Posted December 31, 2014 Same relative deal for November: November 2014 averaged 48.0 degrees at DCA (1.6 degrees below the 1981-2010 normal), but only 41.8 at IAD (4.6 degrees below the 1981-2010 normal). The 6.2 degree monthly differential brings the 11-month average differential to 5.45 degrees -- again the second largest ever. 1976 averaged a 6.05 degree differential through November. December 2014 averaged 43.7 degrees at DCA to bring the yearly average to 58.5 degrees, but only 38.3 degrees at IAD to bring the yearly average to 53.0 degrees. Thus, the 2014 differential was 5.5 degrees, tying 1975 for the second greatest differential ever, behind the 5.9 degree differential of 1976. The 58.5 degree average at DCA was the coldest only since 57.4 degrees in 2009, whereas the 53.0 degree average at IAD was the coldest since 51.9 degrees in 1976. Link to comment Share on other sites More sharing options...
Ian Posted January 2, 2015 Share Posted January 2, 2015 Dec tied for the warmest monthly low on record at DCA/DC old. Let's hope this is not a useful metric as the last two rolled forward are no bueno. Link to comment Share on other sites More sharing options...
EastCoast NPZ Posted January 2, 2015 Share Posted January 2, 2015 ohh to have lived in 1880. Link to comment Share on other sites More sharing options...
RodneyS Posted January 2, 2015 Share Posted January 2, 2015 ohh to have lived in 1880. December 1880 was only the fourth coldest December in DC history, with an average temperature of 29.0 degrees (1876: 27.1; 1917: 27.9; and, as some of us remember, 1989: 27.9), but it did end on a rather chilly note, with a memorable New Year's Day morning low: Dec 30, 1880: Max 9, Min -7 Dec 31, 1880: Max 13, Min -13 Jan 1, 1881: Max 19, Min -14 In contrast, December 1989 managed a low of only 5 above zero (on the 22nd), and was relatively balmy on New Year's Eve (Max 46, Min 33) and New Year's Day 1990 (Max 46, Min 35). Link to comment Share on other sites More sharing options...
RodneyS Posted February 1, 2015 Share Posted February 1, 2015 December 2014 averaged 43.7 degrees at DCA to bring the yearly average to 58.5 degrees, but only 38.3 degrees at IAD to bring the yearly average to 53.0 degrees. Thus, the 2014 differential was 5.5 degrees, tying 1975 for the second greatest differential ever, behind the 5.9 degree differential of 1976. The 58.5 degree average at DCA was the coldest only since 57.4 degrees in 2009, whereas the 53.0 degree average at IAD was the coldest since 51.9 degrees in 1976. January 2015 continued the trend of a big DCA/IAD average temperature differential. DCA averaged 35.6 degrees, while IAD averaged just 29.7. The 5.9 degree differential is the largest in January since 1984, when the differential was 6.4 degrees. The largest January differential was 6.9 degrees in 1975, while the smallest was 1.3 degrees in both 2005 and 2006. Link to comment Share on other sites More sharing options...
aldie 22 Posted February 4, 2015 Share Posted February 4, 2015 I fully expect next week there will be a post in here about our regions first 60 hour continuous snowfall Link to comment Share on other sites More sharing options...
wxdude64 Posted February 4, 2015 Share Posted February 4, 2015 I fully expect next week there will be a post in here about our regions first 60 hour continuous snowfall Even if it is 1/8-1/4 inch an hour rates. Link to comment Share on other sites More sharing options...
PrinceFrederickWx Posted February 15, 2015 Share Posted February 15, 2015 For BWI, in addition to tying the record low today, its seems like breaking the record lowest max today and record low tomorrow are given. Also... top 10 coldest February watch for BWI? Link to comment Share on other sites More sharing options...
MN Transplant Posted February 15, 2015 Author Share Posted February 15, 2015 For BWI, in addition to tying the record low today, its seems like breaking the record lowest max today and record low tomorrow are given. Also... top 10 coldest February watch for BWI? We are going to put down some nasty departures as the norms go up in late Feb. Will be interesting to track. Link to comment Share on other sites More sharing options...
RodneyS Posted February 16, 2015 Share Posted February 16, 2015 We are going to put down some nasty departures as the norms go up in late Feb. Will be interesting to track. It looks as if IAD is headed for its coldest February since 1979. DCA could achieve that as well, but February 2007 featured a negative departure relative to the 1981-2010 normals of 8.1 degrees (15th coldest February in DC history), so that could be a close call. Link to comment Share on other sites More sharing options...
Ian Posted February 16, 2015 Share Posted February 16, 2015 Plop these in here. Looks like final numbers. Already down to 13 at DCA.. today may play too I guess. Euro/GFS hinting subzero late week.. with snow it might be believable even into DC? Prelim this looks like the coldest Feb day at DCA since 1996. Also the coldest since 1979 Feb 15 and beyond.. 6th coldest this late at DCA. Link to comment Share on other sites More sharing options...
PrinceFrederickWx Posted February 16, 2015 Share Posted February 16, 2015 So for BWI: Record lowest max and record low tied yesterday (18 and 6) Record lowest max and record low tied today (18 and 5) Seems likely that we will break a few more later this week. This is quickly turning into a historic February. Link to comment Share on other sites More sharing options...
mattie g Posted February 17, 2015 Share Posted February 17, 2015 Weather Underground forecast has me at -7 on Thursday. Pretty sure that's be the coldest I'd be since I moved to the area in 1997. We had a couple mornings below zero last year, but not that cold - maybe -3 or so...can't quite recall. Either way, that's damn cold, let alone for nearly the end of February. Link to comment Share on other sites More sharing options...
RodneyS Posted February 17, 2015 Share Posted February 17, 2015 Weather Underground forecast has me at -7 on Thursday. Pretty sure that's be the coldest I'd be since I moved to the area in 1997. We had a couple mornings below zero last year, but not that cold - maybe -3 or so...can't quite recall. Either way, that's damn cold, let alone for nearly the end of February. Weather Underground currently forecasts -6 at Dulles Airport on Thursday morning. If that holds -- or even if the minimum reaches -3 -- that would be the coldest there since -9 on February 6, 1996. The all-time low at Dulles was -18 on January 22, 1984. The all-time February low there was -14 on February 18, 1979 -- the Sunday of the first Presidents Day storm. Link to comment Share on other sites More sharing options...
Ian Posted February 17, 2015 Share Posted February 17, 2015 DCA 20/10 today beats yesterday's coldest Feb day since 1996 avg. Link to comment Share on other sites More sharing options...
PrinceFrederickWx Posted February 19, 2015 Share Posted February 19, 2015 So for BWI... record lowest max broken today (18). Record low should probably be broken tonight. Then tomorrow's record lowest max is in play, as well as the record low for Saturday. LWX needs to update their February records page for BWI though... they usually do it the next day or so but they haven't added the ones from earlier this week. Link to comment Share on other sites More sharing options...
RodneyS Posted February 21, 2015 Share Posted February 21, 2015 It looks as if IAD is headed for its coldest February since 1979. DCA could achieve that as well, but February 2007 featured a negative departure relative to the 1981-2010 normals of 8.1 degrees (15th coldest February in DC history), so that could be a close call. The coldest IAD and DCA Februaries since 1979 are now pretty well assured. Further, both airports are headed for the coldest second half of February (15th-28th or 29th in leap years) in their respective histories. Finally, and most remarkably, DCA is very likely to break the record for the coldest second half of February in DC history. The current record holder is February 15-28, 1934, which averaged 24.9 degrees at the Weather Bureau location at 24th and M Streets, NW. If National Weather Service, Weather Channel, and AccuWeather forecasts through the end of the month come even close to verifying, that record will be broken by at least a degree or two. Link to comment Share on other sites More sharing options...
Ian Posted February 22, 2015 Share Posted February 22, 2015 7 day avg of 19 ending yesterday was the coldest week for DC since Jan 1994, which bottomed at 13.8. Link to comment Share on other sites More sharing options...
RodneyS Posted February 24, 2015 Share Posted February 24, 2015 Weather Underground currently forecasts -6 at Dulles Airport on Thursday morning. If that holds -- or even if the minimum reaches -3 -- that would be the coldest there since -9 on February 6, 1996. The all-time low at Dulles was -18 on January 22, 1984. The all-time February low there was -14 on February 18, 1979 -- the Sunday of the first Presidents Day storm. Last Thursday didn't work out, but this morning did: -4 at Dulles. That's the coldest ever there this late in the winter. Link to comment Share on other sites More sharing options...
PrinceFrederickWx Posted February 25, 2015 Share Posted February 25, 2015 So far, this is the 2nd coldest February at BWI: 1934 - 24.3 degrees2015 - 25.3 degrees1979 - 25.6 degrees Link to comment Share on other sites More sharing options...
PrinceFrederickWx Posted February 26, 2015 Share Posted February 26, 2015 I think BWI will finish either 2nd or 3rd coldest February. That will also be a top 10 coldest month overall. Rodney or MN (or anyone), how does it look for DCA and IAD rankings? I don't keep spreadsheets of those. Link to comment Share on other sites More sharing options...
Ian Posted February 26, 2015 Share Posted February 26, 2015 I think BWI will finish either 2nd or 3rd coldest February. That will also be a top 10 coldest month overall. Rodney or MN (or anyone), how does it look for DCA and IAD rankings? I don't keep spreadsheets of those. BWI should get 2nd as 1979 finished a bit mild. Dulles is close but seems it'll miss 1979 by a smidge for number 2? DC is like top 15. Link to comment Share on other sites More sharing options...
RodneyS Posted February 27, 2015 Share Posted February 27, 2015 BWI should get 2nd as 1979 finished a bit mild. Dulles is close but seems it'll miss 1979 by a smidge for number 2? DC is like top 15. Dulles is a lock for the second coldest February there, but 1979 is now out of reach due to the warm-up yesterday afternoon and today. As Ian notes, DCA will finish in the Top 15 coldest in DC history, but will also finish warmer than in 1979. However, DCA still has a chance for the coldest last half of February in DC history. Further, the second half of February at both IAD and DCA will finish way colder than in 1979. Link to comment Share on other sites More sharing options...
RodneyS Posted March 1, 2015 Share Posted March 1, 2015 Dulles is a lock for the second coldest February there, but 1979 is now out of reach due to the warm-up yesterday afternoon and today. As Ian notes, DCA will finish in the Top 15 coldest in DC history, but will also finish warmer than in 1979. However, DCA still has a chance for the coldest last half of February in DC history. Further, the second half of February at both IAD and DCA will finish way colder than in 1979. February 2015 appears to be finalized at 30.3 degrees for DCA and at 25.4 degrees for IAD. That makes each airport the coldest in February since 1979 (DCA: 28.4, IAD: 23.3), and it places DCA 14th coldest of 145 years in DC history and IAD second coldest of 53 years in Dulles history. February 2015 was also the coldest month experienced at DCA since January 1994 (28.8) and at IAD since December 1989 (23.1). For the meteorological winter as a whole, DCA averaged 36.5 -- pretty much in the middle at 68th coldest of 144 seasons and coldest only since 2009-10 (35.8). However, IAD averaged just 31.0 -- the 7th coldest of 53 seasons there and coldest since 2002-03 (30.7). Regarding the last half of February 2015, it was a case of "missed it by that much" at DCA. It averaged an even 25.0 degrees from the 15th to the 28th, which was just a tenth of a degree warmer than February 15-28, 1934, and 1934 also holds the record for the coldest February as a whole, at 24.6 degrees. However, the last half of February 2015 was 7.3 degrees colder than the last half of February 1979 at DCA, and IAD's February 2015 last half average of 19.5 degrees was 7.5 degrees colder than the last half of February 1979 there. Link to comment Share on other sites More sharing options...
PrinceFrederickWx Posted March 1, 2015 Share Posted March 1, 2015 BWI finished February at 25.3 degrees, making it the 2nd coldest February ever and 5th coldest month ever (top 10 coldest months are listed below): Jan. 1977 - 22.9 degrees Jan. 1918 - 24.2 degrees Feb. 1934 - 24.3 degrees Jan. 1893 - 24.3 degrees Feb. 2015 - 25.3 degrees Dec. 1989 -25.4 degrees Jan. 1982 - 25.5 degrees Feb. 1979 - 25.6 degrees Jan. 1912 - 25.8 degrees Jan. 1940 - 26 degrees This was also the 2nd coldest Jan-Feb period ever for BWI at a combined average of 28.1 degrees (the first was 1904 at 28.0 degrees). May be too soon but... could BWI try making a run for top 10 coldest year again this year? Edit: I forgot about Dec. 1989 so its been put in the list. I hadn't even bothered checking Dec. cause I figured it couldn't even compete. Wow... Link to comment Share on other sites More sharing options...
WxUSAF Posted March 3, 2015 Share Posted March 3, 2015 10 below normal months at BWI in the period of November 13-February 15. February 15, January 15, November 14, August 14, July 14, April 14, March 14, February 14, January 14, November 13 That's a pretty impressive run given climate and UHI both progressively working against below normal temps. Maybe some of the stat-minded folks can tell us how exceptional it is? Link to comment Share on other sites More sharing options...
RodneyS Posted March 3, 2015 Share Posted March 3, 2015 10 below normal months at BWI in the period of November 13-February 15. February 15, January 15, November 14, August 14, July 14, April 14, March 14, February 14, January 14, November 13 That's a pretty impressive run given climate and UHI both progressively working against below normal temps. Maybe some of the stat-minded folks can tell us how exceptional it is? That depends on what probability assumptions you make. For example, during February 2011-October 2012 inclusive, every month (21 straight) at BWI was above normal, leading some to believe that the probability of a below normal month there had fallen well below 50% -- possibly as low as only 20-30%. However, since then only 13 of 28 months have been above normal at BWI. If you do a straight binomial calculation, the odds of 10 of the last 16 months being below normal there are as follows, given these probabilities of a below normal month: 50% chance of below normal month: 22.7% chance of at least 10 months being below normal. 40% chance of below normal month: 5.8% chance of at least 10 months being below normal. 30% chance of below normal month: 0.7% chance of at least 10 months being below normal. 20% chance of below normal month: 0.02% chance of at least 10 months being below normal. So, I would conclude that the probability of a below normal month at present is much closer to 50% than it is to 20%. However, we could simply be in an unusual run of below normal months. Nonetheless, the probability of 21 straight months being above normal followed by only 13 of 28 months being above normal simply due to random factors is unlikely in the extreme. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now