MONTHLY SUMMARY: NOVEMBER 1997 UPDATED: 12/25/97 --------------------------------------------------------------------------- A joyous holiday season to everyone!! Well, don't need to look too hard to find the highlight headline for November. "Rainy and cool" with many sites reporting several inches of excess rainfall when compared to the norm. Temps at most stations were well below normal. Many locations noted all November weekends having rain, and some stations could track rainy weekends back to October 18/19!! No major storms occurred throughout the area although some stations reported some fantastic rainfalls from more isolated weather features. By now, each of you has noted the never-ending zonal flow which resulted from a split flow of the northern and southern jets. It seems a month now that this pattern has persisted with the arctic/polar cold kept north along and to the north of the US/Canadian border. Meanwhile, the southern jet is transporting those storms coming in on the CA coast southeast to AZ and NM then east and northeast to New England. With the lows dipping into northern Mexico before reforming over the Texas heartland, cold air has been sucked south giving the southwest some remarkable, repetitive snowfalls. Back East, the pattern has resulted in weak high pressure flowing in at the surface from the west and northwest with a dominant southwest flow aloft. On occasion, we've seen cold Canadian air ridge down the East Coast and east of the Appalachians and Smokies with center over Eastern Canada or New England. What is so striking about this split flow pattern is its duration. Rest assured there will be changes which will affect us in a variety of ways. Nature balances/corrects itself continuously. Too, remember we've had- for the most part- consecutive, cool months and October and November saw repeated troughs over the East, a pattern we would need to drop cold air into the region and set-up phasing with the moist subtropical jet (can you read "snow!"). Most important, meteorological winter has just begun and, although many of you are used to snowfalls by now, we have a long stretch ahead. Of course, those of you who distain "honkers" (those of us who repeatedly want snowstorms and sound like "honking geese" when we say the word snow) are probably fine and dandy with our rather uneventful weather! Looks to me like we'll need a ridge in the west and a major storm to develop a trough in the East, but where is that scenario? We may need a major low to develop in the mid or northern Plains states to dig a trough into the midwest and then on to the east. And a few clippers might help as well. These Texas panhandlers on the other hand are doing us no good in returning colder weather to the Eastern Seaboard. Time will tell... ----- Instrument calibration time! John Bullock just acquired a new Taylor Maximum/Minimum thermometer that I assume is the standard "greenhouse" type mercurial thermometer. These are VERY accurate and I've used two calibrated together which have remained identical in readout over 20 years. They have become the standard to which I have calibrated all my temperature sensors over the years, particularly the electronic instruments. Through time and a variety of circumstances, however, these instruments can loose their accuracy. For instance, the Taylor mercurial thermometer's U-tube can shift or the left and ride side scales behind either side of the tube can move. Since they can be adjusted by untightening a main screw, they should be kept in mind as well when calibrating. The scales on both sides behind the U-tube should give the exact same reading. Correct calibration is easily achieved by using one instrument as a standard for your other sensors. If you can not trust the accuracy of your temp readout, look for a source that provides information on how to calibrate temp, for instance using the ice water method. Don't try to set temp using info from a local ASOS station or by telephone using the newspaper's or phone company's sensors. Distance from your station and conditions under which those sensors are mounted can create a huge difference from the weather at your site, if only a few blocks away!! Instrument cleaning and calibration is a MUST activity several times a year for most of us. If, on the other hand, you're like many and calibrate only once a year, then the week before New Year's Day is an excellent time. Any ideas on calibration, then send them along. ----- I've attached a copy (not on internet site) of the NOAA and NWS "Snow Measuremenet Guidelines." Thanks to Kevin Shaw, ACON DC/MD/DE coordinator for passing along the info. Also, you can read a copy of member Lowell Koontz' "Snowfall Measurement" article at the ACON VA/NC/SC home page site at http://www.pilot.infi.net/~bsmoot/acon.htm ----- Stamp balances ----------------------------------------------------------------------------- NOTES FROM "AROUND THE LEAGUE"- Arlington - The monthly average temp here was 3.7 degrees below normal while precip was +1.48" A new daily rainfall record was set on the 7th with 2.00" The month was cold, reasonably cloudy, and had a "nasty habit" of producing rainfilled weekends. The month was the 3rd coldest November in the past 20 years. Boston - Tom reports a warm Thanksgiving this year when the temp reached 62 degrees on an other otherwise usually chilly day. Bridgewater - Clayton Towers sends this report: "Precipitation for the month of November was 2.09 inches above normal. with the heavy rains, precipitation for the year is 0.33 inches above normal now. November was a rainy month. Freezing rain occurred on the night of the 13th. The first sign of snow for the fall season occurred on the 15 from a heavy flurry. The ground was white in places, but the snow was not measurable. Outside of the rain, november was rather boring weatherwise. Centreville - Paul Bassett reports that November had 7 days on which the wind gusted to 30 mph or greater. The monthly rainfall was well-over doubled the normal and 150% more than the rainiest month of 1997, August, which only ran 30% of normal for 1997. He adds that he usually admires well-behaved kids but El Nino is proving to be an exception. He adds to "watch-out DC, the brat is coming to your town!" Falls Church - Cool and wet highlights Lowell's descriptors/info. The mean temp was 1.49 below normal and was the 4th lowest in the last 12 years. Precip was 1.29" above normal. Only two days during the month reached above 59 degrees. The month was the cloudiest November since 1992. In over 12 years, November 1997's humidity levels were the highest! This was also the first November without at least a little snow since 1994. Falls Church - Erica noted a very wet month with a whopping excess departure of 4.63" November was a rather cool month with the average high some 3.9 degrees below norm. The average low was 1/2 degree above normal. Fredericksburg - November was a much and cooler month compared to averages. (from Ken McKneely) Hampton - Above normal precip here, says Dave, which had helped improve the year-to-date rainfall. Dave's still 10.00" below normal for 1997. Temps were slightly cooler than November norms. Louisa - John writes that he has a new max/min thermometer and notices readings above what he has "been used to." This brings to mind that it's time for recalibration of your instruments. See opening note. Mechanicsville - Heavy rain with thunder moved through the Glenn's area around 3 AM on the 14th. Newport News - Gary reports a monthly total of 7.26" was a record for his station. Temps averaged 2.9 degrees below normal with record lows set on the 18th, 19th, and 25th and tied on the 17th and 20th. Norfolk - Temps were 2.2 degrees below normal and precip was 2.09" above normal. The month was rather rainy and chilly. November 1997 was the 14th wettest November on record. Several spots throughout Hampton Roads reported significantly more rain than did ORF. Courtland had 6.49" and James City County on the Peninsula reported 5.89" Every weekend in November reported rainfall with rainy weekends dating back to October 18/19. November '97 was the 16th coldest November on record. Despite the monthly low temp (a record-tying for the date) of only 27 on the 18th, many outlying areas had much lower readings. Portsmouth - Twelve of 30 days with measurable precip certainly qualifies November as a rainy month. The month ended some 1.43" ABOVE normal. Temps averaged 2.2 degrees below normal. On the 24th, a cold front brought a wind gust of 46 mph from the north-northwest. The abundantly moist air resulted in 5 frosty mornings when the weather did clear-out and winds died off. The month remained nearly 11 inches BELOW normal precip for the year. Richmond - According to Roy, November had the most rain for any month so far this year. June was the month with the second highest total. The 24-hour total on November 7 was the highest daily total since September '94 when 3.48" fell on the 22nd. Richmond - The month was rainy and chilly. Rainfall was 200% of the normal and several spots north and east of RIC had significantly more rainfall that did the airport. Lancaster County in the Northern Neck reported over 7" of rain. The month was the 13th wettest on record and was the 14th coldest on record. Roanoke - Wednell reports in stating there were no big storms during the month. Temps were some 3.4 degrees below normal. Rainfall here, unlike most of our reporting sites, was 1.34" BELOW normal. Stafford - November was the rainiest month since July 1996. Precip is now 1.27" above normal year-to-date. Mean maximum temp for the month was 5 degrees below normal. Weems - Francis explains that his late reports have been due to bouts with the flu. Despite his shots, he hasn't been doing too well. But, he adds, "I am improving, but at 84+, it takes me longer to get back into the swing of things. I am now in weather forecasting for 72 year. There are not many of us left. We still learn things!" (Editor's note: I can only hope to be so lucky as to work in weather that long or to even live that long! Way-to-go Francis. Take care and rest up before the winter snows keep you inside!!) Woodstock - The third consecutive "very cold" November. The month was very wet according to Lauck, with the second highest total in 12 years of records. Asheville - NWS GSP reports the average monthly temp was 5.2 degrees below normal while rainfall was 1.99 inches below normal. Brevard - November was a cool month in Bob Keehn's Brevard. The mean low and mean high were each four degrees below the 1990-1994 means but well-above the 20.6 and 46.6 means of November 1996. Rainfall amounted to 2.29" or about half to be expected and in spite of the fact that measurable amounts of rain were recorded on ten of the 30 days in the month. The first snow, a brief flurry leaving a trace, occurred on the 19th. Charlotte - Slightly above normal precip here (+0.53") with temps 3.4 degrees below normal. Greensboro - At this Piedmont station, temps were 4.5 degrees below normal while precip was slightly below the norm or -0.32". Henderson - George writes that his temps were below normal while rainfall was above normal. Herndon - Second highest November precip here in the 22 years Bob has been at this station. Raleigh - NWS RDU notes an average temp some 3.9 degrees below the normal. Precip totals were 1.07" above normal. A new monthly record low was set on the 17th when the temp dropped to 23 degrees. Raleigh - Cold and wet describes the month of November in Bob Woodson's territory. The average daily temp was more than 4 degrees below normal. This is the 8th consecutive month of below normal temps. He adds, "Hope this continues through the winter." Rockwell - November was cold reports Tom Myers. The month was not only colder but also wetter than nomral. The mean temp was 6.3 degrees below normal with rainfall slightly above (+0.26"). We had quite a few raw breezy days with northeast winds and drizzle. Roxboro - Merriell noted a breezy, cooler, and wetter than normal month. Brilliant fall foliage during most of the month. Wilmington - "The cool swing continues" here with temps some 3.9 degrees below normal. This was the 10th consecutive month on the cool side. A 25 degree reading on the 18th set a new record low for the date. Rainfall departure from normal was +2.54". Columbia - Abundant rainfall was noted here (+1.85" departure) and the average temp was some 4.2 degree below normal. Greenville-Spartanburg - The average monthly temperature here was 4.7 degrees below normal. Rainfall was about normal, +0.05" Ruby - November, according to Franklin, was a damp and rather cool month in Ruby. Tri-cities - The average monthly temp was 5.5 degrees below normal and the total precip was 1.23" below the norm. ----------------------------------------------------------------------------- UPDATED MEMBERS' E-MAIL ADDRESSES: (posted by permission) BRE Bob Keehn Bob_Keehn@citcom.net BRI Clayton Towers Ctowers@rica.net POR Bill Trotter wtrotter@whro.org RAL Bob Woodson woods@pipeline.com CEN Paul Bassett III pbassett@digizen.net WSH David Yowell deyowell@mnsinc.com FCH Erica Page erica@erols.com RMD Roy Britt rbritt@erols.com NEW Joyce Winfree joywood@shentel.net FRB Ken McKneely k7m@fls.infi.net STF Danny Jessee tornado@tidalwave.net BOS Thomas Hensley thomas@summit.net RWL Tom Myers tmyers@salisbury.net -----------------------------------------------------------------------------