Thursday, October 18, 2007

DC Held Rainless: Day 34 ?
Chance of showers better tomorrow


Variable clouds, warm, more humid. OK, it's not as exciting as an impending snowstorm (and the threat of school closings), but it's an historic event when a record dry spell is broken, even if the last one was set only 12 years ago. With another 7 hours left before the record officially falls, there is actually something to look at on the radar for the first time in many days. The main action is well to the south, where a line of thunderstorms has moved out of southeastern Virginia and over the lower Chesapeake Bay. A small area of showers also extended earlier from Frederick Co. Maryland across the extreme eastern West Virginia panhandle and into western Loudoun Co. This has diminished significantly as it moved into the far western corner of Montgomery Co.

Temperature-wise, it's back to the 80s with both National and Dulles hitting 81° by 2pm. (Relative to the long-term average, that's about 5 weeks later than normal.) Around the metro area, nearly all locations have readings in the upper 70s to low 80s with dewpoints into the moderately muggy mid and even upper 60s.

With this much humidity around and better dynamics, the chances for showers are higher tomorrow.

Tonight and Tomorrow

Mostly cloudy, warm, chance of showers. Mostly cloudy skies tonight will have only a 20% chance of yielding a measurable shower before the record is set at midnight. Lows will be quite mild for the season, in the mid 60s downtown to near 60 in the cooler 'burbs (The record high minimum for the 19th is 65° at National and only 57° at Dulles). Tomorrow will be mostly cloudy with highs 76-80° and a 70% chance of showers or thunderstorms (one model is even calling for a 100% chance). While this could break the rainless streak, most amounts are likely to be less than ¼", barely the average amount for 2 days.

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

Tropical Topics

As the season continues to fade, the tropical Atlantic remains quiet.


The Weather Channel CD is now up to #43 on the Amazon music list.

Wednesday, October 17, 2007

Counting Down to a Rain-Free Record
Weather music works its way up the charts


Sunny, warm, a little more humid. With a large high pressure ridge still dominating, this afternoon's weather map shows virtually no rain anywhere east of the Mississippi. Here in the Washington metro area, bright sunshine and southerly breezes have pushed temperatures back into the 80s for the first time in a week; by 4pm, National was at 82°, 14° above average.

At post time, we are roughly 7 hours from tying the 1995 record of 33 consecutive days without measurable rain. Whether the streak lasts through tomorrow is a little more problematic, but the chances for precipitation look better for Friday. Fortunately, conditions in this area are not as dire as in large portions of the Southeast, where residents are "Facing Tough Choices". chart from NWS data, photo © Kevin Ambrose

Tonight and Tomorrow

Some clouds, warm. Clouds will be scattered to broken overnight with lows in the low 60s downtown and the mid and upper 50s in the 'burbs. Some mist or fog is possible in the early morning hours. Tomorrow will have increasing clouds in the afternoon but only a 30% chance of showers and continued warm temperatures, highs 76-79°.

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


If you're bored watching grass die, the Discovery Channel premieres a new series tonight called "Storm Chasers". The show pairs up tornado researcher Dr. Josh Wurman and his Doppler on Wheels (featured in Nancy Mathis' book "Storm Warning") with an IMAX filmmaker and the TIV (Tornado Intercept Vehicle), which looks like it escaped from a steroid explosion at the BattleBot lab. The program is scheduled for 10pm on Wednesdays, with repeats Friday nights at 8 and midnight, Mondays at 10, and Tuesdays at 2am.

The Weather Channel CD compilation of Weather on the 8's smooth jazz, which Jason posted about yesterday, has risen to number 60 for sales in the music category and number 1 for jazz compilations at Amazon.

TIV photo from Discovery Channel

Tuesday, October 16, 2007

Double Digit Deviations
Warm October continues into second half


Mostly sunny, warm. A high, thin overcast at times has not been enough to keep high temperatures from once again soaring to double digit deviations from the long-term average. By 4pm, National had reached at least 79°, (11° above average) and Dulles was 78°. Through the first half, the monthly average is now 9.2° above average. In the unlikely event this were to continue, the month would end up being nearly 4° above the record warmest October in 1984. One indication of the remarkable warmth of the past 2 weeks is that the average daily low so far of 61.5° would be high enough as an overall average to put the month in the top 20 warmest Octobers of the last 137 years.

No rain is in sight for at least the next couple of days.

Tonight and Tomorrow

Warm, dry. A crescent moon will share the sky with some thin clouds tonight. Lows will be in the upper 50s to near 60° in the city and low to mid 50s in 'burbville. Tomorrow should be mainly sunny and continued warm with highs 78-82°.

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

Capitol Climate

The House Committee on Science and Technology's Subcommittee on Investigations and Oversight is holding a hearing tomorrow (10am, 2318 Rayburn HOB) on the effect of climate change on the Arctic, with particular emphasis on the threat of permafrost melting as a possible tipping point through the release of methane (not included in the modeling used for the most recent IPCC report). Other topics include "projections regarding the future survival of the polar bear; the loss of sea ice in the Arctic and new research on ice sheet melting; the decline of the boreal forests of the Arctic due to global warming; and strategies to reduce black soot and methane among other greenhouse gases."

Monday, October 15, 2007

October Fester


Sunny, warm. The deepening drought continues to slowly fester across the Nation's Capital region. Although it's not likely to last, as we reach mid-month, this October is still tied with October 1963 as the driest month ever recorded in Washington. On the other hand, we are now within only a few days of the longest rainless streak with only a trace in the last 31 days. The 1963 streak of 32 days began following almost 2" of rain on Sept. 29 and ended with nearly 1" on Nov. 1 for the start of a a very wet month totaling 6.7". The 1963 trace at National was also duplicated at then brand-new Dulles Airport. The record streak was broken in 1995 with 33 days from Aug. 7 to Sept. 8.

The 30-day percentage of normal precipitation from the NWS New Precipitation Analysis shows the worst impacts from the District south, where the darkest red indicates only 0-5% of average. The lighter red to the north and west represents 10-25%, and even the orange over northeastern Maryland is in the 25-50% range.

Under bright October sun and a mostly westerly breeze, temperatures this afternoon have climbed to the mid and even upper 70s; National was 77° at 3pm before an easterly wind knocked the reading down a couple of degrees. Dewpoints are in the dry low to mid 40s.

Although the main storm track this week is through the center of the country, the best chance in a while for at least some rain (but not the soaking variety) is starting to shape up for Friday or Saturday.

Tonight and Tomorrow

Seasonably warm, dry. Mostly clear to partly cloudy and dry conditions will continue through tonight, with lows in the mid 50s in the city and the upper 40s to low 50s in the 'burbs. Mostly sunny skies in the morning will give way to more clouds in the afternoon tomorrow with highs 74-78°.

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

Tropical Topics

The National Hurricane Center is watching an area of thunderstorms in the southwestern GoMex (Gulf of Mexico). Only slow development, if any, is expected, but that didn't stop energy market commentators from citing it this morning as a reason for the record-breaking oil price of $85 a barrel.

Political Science

You don't need to be a weatherman to predict the reaction to Friday's announcement of the Nobel Peace Prize. McClatchy newspapers, via the SeaTimes, report that Colorado State's William Gray called global warming theories "ridiculous" in a lecture at UNC Charlotte. The Deltoid science blog, via a link from the Ol' Perfesser, provides a handy directory to some very creative expressions of "Gore Derangement Syndrome".

Also on the opinion front, atmospheric sciences professor Judith Curry of Georgia Tech has a thorough critique of many of the flaws in Bjorn Lomborg's WaPo climate policy opinion piece last Sunday.

Seasonal Outlook

Latest seasonal forecast: Click here.

Latest 3-month temperature outlook from Climate Prediction Center/NWS/NOAA.