Frigid Friday: A Callendar Effect

Now

Sunny, breezy, cold. After last evening's scattered first flurries of the season, temperatures have struggled to get beyond the mid 30s throughout the National Capital region this afternoon under mostly clear skies and brisk northwesterly breezes. Highs were unofficially 35° at National and 33° at Dulles.

Tonight and Tomorrow

Cold, then moderating. Under clear skies and light winds, tonight's lows will be near 20° downtown, ranging as low as the low teens in the 'burbs. Temperatures will rebound to much more seasonable levels tomorrow. Highs will be in the mid 40s with mainly clear skies.

For the outlook through the rest of the weekend, scroll down to Camden's post below.

Tropical Topics

The Atlantic hurricane season officially ended last week, so it must be time for the 24th annual extended hurricane season outlook for 2007 issued today from land-locked Colorado State. The forecast calls for above-average storm activity, with a total of 14 named storms, including 7 hurricanes, 3 of those severe. The long-term average numbers are 9.6, 5.9, and 2.3, respectively.

Climate Calendar

This Monday, the 11th, from 3-5pm, the Woodrow Wilson International Center is presenting a seminar entitled, "Climate Change: Historical Perspectives and the Current Debate". The speaker, James Fleming, is Professor of Science, Technology, and Society at Colby College. He is the author of "The Callendar Effect", which has just been published by the American Meteorological Society. The book is

the untold story of the remarkable scientist who established the carbon dioxide theory of climate change. Guy Stewart Callendar discovered that global warming could be brought about by increases in the concentration of atmospheric carbon dioxide due to human activities, primarily through burning fossil fuels. He did this in 1938!

The event is also scheduled to be webcast live. The Wilson Center is located adjacent to Federal Triangle Metro.

Transition Thursday; The "S" Word?

Now

Sunny, breezy, turning colder. After temperatures reached an unexpectedly high 56° around noon, the first phase of a double-barreled cold front passed through the metro area, lowering readings mainly into the 40s by early afternoon. At 4pm, Leesburg and Winchester were even into the upper 30s.

By mid afternoon, scattered snow flurries on radar were moving eastward, but only as far as I-81. To mix a metaphor, the other shoe drops tonight, when the Arctic air west of the mountains will come into the region on strong northerly winds. The "S" word of the day is "slight", as in chances of a light flurry east of the Blue Ridge.

Surface weather map at 1pm today from HPC/NCEP/NWS

Tonight and Tomorrow

Much colder. Tonight will be windy and cold under clearing skies; lows will be in the low to mid 20s. There is a slight chance of a passing snow flurry through this evening. Tomorrow will be sunny and brisk, windy with highs only near 36°.

For the weekend outlook and beyond with Larson's Long-Range, scroll down to Josh's post below.

El Niño Update

The NOAA/NCEP/Climate Prediction Center (CPC) today published the monthly El Niño Diagnostic Discussion. As shown in the chart, sea surface temperature anomalies have continued to increase in the tropical Pacific. In the month ending last week, the maximum departures from the long-term average were over 2°C (red area) near the International Date Line.

The outlook calls for the El Niño conditions to continue to increase through the winter months, followed by weakening from March to May next year. CPC's Dr. Vernon Kousky said that "typical El Niño effects over the U.S. during January through March 2007" can be expected. These effects are reflected in the NOAA winter outlook, which calls for near to above normal temperatures and near normal precipitation in the Mid Atlantic region, with the polar jet stream remaining primarily in Canada.

The CPC analysis is consistent with the latest report from the UN's World Meteorological Organization (WMO). The WMO notes that El Niño impacts are already significant in the western Pacific, with severe drought occurring in Indonesia and Australia, where the worst conditions in a century are impacting economic growth. Eastern equatorial Africa is also being affected, but by flooding from heavy rains.

Brief Cold Shot on the Way

Now

Sunny, seasonable. Southerly breezes gusting over 20 mph at times have lifted temperatures back to seasonable levels in the Washington metro area this afternoon under sunny skies. Highs were 51° at both National and Dulles as well as at BWI. A new cold shot arriving late tomorrow will be sharp but short in duration as milder air returns by the weekend.

Tonight and Tomorrow

Mostly clear, not as cold. Lows tonight under mostly clear skies will be in the mid 30s in town to near 30 in the cooler 'burbs. Tomorrow will be partly cloudy with highs in the upper 40s but turning windy and colder by late in the afternoon. There is a slight chance of isolated snow flurries.

For the outlook through the rest of the week into the weekend, scroll down to Dan's post below.

Tropical Topics

As indicated here yesterday, Bill Proenza was announced today as the new Director of the National Hurricane Center. Proenza was appointed Director of the National Weather Service Southern Region in 1999. He was selected as a Fellow of the American Meteorological Society in 2003.

Photo of Bill Proenza from NOAA

A report today by the Government Accountability Office says that FEMA has misspent at least $1 billion of Hurricane Katrina aid on fraud and abuse. The amount includes $20 million paid to thousands of people who filed claims for the same damage from both Katrina and Rita.

Clearly Cold; Center Contenders Considered

Now

Sunny, cold. After early afternoon highs slightly over 40°, temperatures have dropped back to the 30s late this afternoon in the Washington metro area. Skies are mainly clear after some earlier clouds and a few very isolated snow flurries. Cold and dry conditions will continue through tomorrow.

Tonight and Tomorrow

Mostly clear, cold. Lows tonight will be similar to last night's under mainly clear skies, upper 20s downtown to low 20s in the 'burbs, some upper teens possible in the outlying areas. Skies will be mostly sunny tomorrow with more seasonable temperatures, highs near 49°.

For the outlook through the rest of the week into the weekend, scroll down to Jason's post below.

Tropical Topics

NOAA will be announcing the replacement for outgoing National Hurricane Center Director Max Mayfield at the National Press Club tomorrow afternoon. The logical choice would be deputy director Ed Rappaport, but he is reported by the Miami Herald to have declined to apply. According to the same article, Bill Proenza, current director of the NWS Southern Region, is the leading contender. Other candidates, however, are Steve Letro, meteorologist in charge of the Jacksonville office, Bill Reed, in charge of the Houston office, and Richard Knabb, a forecaster at the Hurricane Center.

Miami's WPLG, Channel 10, among the child run over by grandma, shots fired near middle school, and $35K worth of iPods missing from Best Buy stories, is more definite about the choice. Bob King's Eye on the Storm blog in the Palm Beach Post, on the other hand, is unsure. Retiring director Mayfield was recently profiled in the Tampa Tribune.

Max Mayfield photo from Tampa Tribune.

DC: December Chill, Displaying Calendars

Now

Windy, cold. A low pressure area which developed off Cape Hatteras last evening brought some light to moderate rain to the Northern Neck, Southern Maryland, and the Eastern Shore before scooting away to the Nova Scotia coast early this afternoon. As it strengthened rapidly, the counter-clockwise flow brought a reinforcement of cold and dry air to the Washington metro area on winds gusting over 30 mph at times.

Afternoon highs have been the coldest of the season, generally in the upper 30s; the daily highs at Dulles (39°) and National (41°) were both between 4:00 and 5:00 this morning. The dewpoints are mainly in the low teens and there are even some single digits around the region.

Surface weather map at 1pm today from HPC/NCEP/NWS

Tonight and Tomorrow

Clear, cold. As winds diminish tonight under mainly clear skies, temperatures will drop to the mid 20s in the city and the upper teens in the coldest 'burbs. Tomorrow will be sunny with highs near 40°.

For the outlook through the rest of the week into the weekend, scroll down to Jason's post below.

Weather Pinups

It's calendar time again. It may not be as sexy as Weather Babes Gone Wild (Mrs. Update wouldn't let us put that one up anyway), but the perennial favorite here at PM Update Command Center is the Weather Guide with Phenomenal Weather Events. This is the 20th anniversary of the calendar which was at one time co-branded with The Weather Channel. Thanks to the merger of the publisher Accord Publishing into the conglomerate Andrews McMeel Universal, the calendar is now available through Amazon and other retail outlets. The discounted Amazon price is cheaper than ordering direct from the publisher, and orders of 3 or more qualify for free shipping.

A little more exotic and also available from Amazon is the 19th edition of the Canadian Weather Trivia Calendar. This one is so hot that a used copy of the 2003 edition is listed for $192.42!