Friday, November 17, 2006

Rain's Reign Rejected


Clear, breezy. Northwesterly breezes gusting over 20 mph have put a slight nip in the air, but temperatures near 60° have made for a rather pleasant mid-November afternoon in the Washington metro area, especially compared to yesterday's drenching downpours. Although National touched 60° early in the afternoon, Dulles made it only to 59°. High pressure building in behind the departed low and some clouds from a weak upper level disturbance will result in seasonable, but cooler temperatures tomorrow.

Tonight and Tomorrow

Some clouds, cooler. Under mainly clear skies and diminishing winds tonight, lows should be near 40° in town and mid to upper 30s in the 'burbs. Partly cloudy skies tomorrow morning will give way to increasing clouds in the afternoon and highs around 54°.

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

Precipitation Perspective

While yesterday's soaking was widespread, amounts varied significantly across the DC/MD/VA region. National and Dulles each recorded respectable amounts over 1", but BWI had 2.35".

Your view of where this fits in the larger scheme of things may have a lot to do with which side of the Potomac you sit on, however. If you've listened carefully to the WeatherTalkers Berk and Pann this year, you may have heard them talk of a Baltimore deficit of precipitation, even after the deluges of early summer and fall. In fact, the current excess of yearly precipitation at BWI of 2.41" is almost completely accounted for by the amount which fell yesterday. The area map, from the NWS New Precipitation Analysis Pages shows the year-to-date precipitation as a percentage of the long-term average. Although areas generally to the south and east of DC are 100-110% of normal (gray) or 110-125% of normal (green), large portions of central Maryland between the Beltways are at 90-100% (light yellow) or even 75-90% (dark yellow).

Thursday, November 16, 2006

After Rain and Wind, Skies Now Clearing


Except for the slight chance of a lingering shower this evening, precipitation has ended across the Washington metro area, with dry conditions likely taking hold for at least several days. Although the rain is for the most part finished, watch out for standing water on the commute home; several water rescues have already been reported.

Earlier today, heavy rain, winds gusting over 40 mph, thunderstorms, and possible tornadoes ahead of a very strong storm system centered in the Ohio Valley prompted numerous watches and warnings throughout the region. For a play-by-play of today's earlier activity, check out the Comments section of Josh's earlier post.

For the outlook through the weekend and beyond, scroll down to Josh's post below.

Pictured: Doppler radar from The Weather Channel shortly before 2pm shows a band of heavy rain across the DC metro area.

Wednesday, November 15, 2006

Showers Developing, Some Possibly Severe


Overcast. Despite some earlier sunshine through the overcast and weak southerly breezes, temperatures have struggled to reach 60° in the Washington metro area today. Although Dulles reached 62° early this afternoon, National only made it to 59°.

As a strong low pressure area in the mid Mississippi/Tennessee valleys continues to develop and move northeastward toward the Great Lakes, showers, some heavy at times, and possible thunderstorms will move into the local area. The AP, via the WaPo non-ex-tree edition, reports that severe storms associated with this system have killed one and injured at least eight people in the Gulf States. The Storm Prediction Center has reported 13 tornadoes so far.

Pictured: Surface weather map and satellite picture at 1pm today from HPC/NCEP/NWS

Tonight and Tomorrow

Showers developing, possible thunderstorms. Showers will develop from the southwest overnight and become heavier and more widespread into the afternoon tomorrow. Rain may be heavy at times, and a few thunderstorms are possible. Lows tonight will be in the low 50s, and highs tomorrow will be around 64°.

For the outlook through the weekend, scroll down to Jason's post below.

Tropical Topics

This year's Atlantic tropical season may have been lackluster, especially by 2005's record-breaking standards, but the eastern Pacific continues to churn out vortices. Sergio became a rare November hurricane this morning, the 10th of the season in the eastern Pacific. This is apparently the first time since 1961 there have been 2 eastern Pacific tropical storms in November. Maximum sustained winds are 105 mph, but the track is expected to remain off the Mexican Pacific coast for the next 5 days.

Also of tropical origin, although not a cyclone, was the moisture which recently brought very heavy rains and flooding to the "other" Washington. NPR's Morning Edition reported this morning that Mt. Rainier National Park remains closed after severe flooding and mudslides from as much as 18" of rain. The unprecedented damage could result in the longest closure of the park's 100+ year history.

Tuesday, November 14, 2006

Mild Mid-Month, Maybe More Moisture Midweek


Partly sunny, mild. Sunshine through breaks in the overcast and mild Pacific-origin air behind the coastal storm of the last several days have pushed temperatures in the Washington metro area well into the mid 60s this afternoon. There have even been some upper 60s in the southern fringes of the region and low 70s in Fredericksburg. Clouds will increase again tomorrow as a new low pressure area getting organized in the southern Plains deepens as it heads on a more westward track for the Ohio Valley, bringing some more rain, especially heavy west of the mountains, on Thursday.

Tonight and Tomorrow

Mostly Cloudy. Under partly to mostly cloudy skies, low temperatures tonight will be from the low 50s downtown to the mid 40s in the 'burbs. Tomorrow will be mostly cloudy with the possibility of showers by evening west of the mountains and highs in the mid 60s.

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

Climate Corner: AMS Draft Policy Statement

The Council of the American Meteorological Society, the nation's oldest and largest organization of meteorologists, has just issued a draft statement on climate change. After reviewing the current state of knowledge of climate change and its effects, the statement concludes:
Despite the uncertainties noted above, there is adequate evidence from observations and climate models to conclude that climate is changing; that humans have significantly contributed to this change; that further climate change will continue to have serious impacts on human societies, on economies, on ecosystems and on wildlife through the 21st century and beyond. Policy choices in the near future will determine the extent of these impacts. Policy decisions are seldom made in a context of absolute certainty. Prudence dictates extreme care in managing our relationship with the only planet known to be capable of sustaining human life.
Comments on the draft statement may be submitted to the Council until December 9. The previous statement on "Climate Change Research: Issues for the Atmospheric and Related Sciences" was published in 2003.

The Council is also soliciting volunteers to help update the "Weather Analysis and Forecasting" statement, which was last issued in 1998.

Monday, November 13, 2006

Fat Lady Fails to Sing


Soggy, cool. Sunday's rain, heavy at times, gave way to Monday's drizzle and mist, but a low pressure area lingering off the Delmarva coast kept the fat lady from singing the final aria in the Washington metro region's soggy opera. Damp conditions will continue through tonight, with gradual drying tomorrow and more pleasant temperatures.

Pictured: Visible satellite image earlier this afternoon from Unisys shows the low pressure area spinning off the coast. (Despite the eye-like appearance of the center, the system has a cold core, rather than the warm core of a tropical system.)

Tonight and Tomorrow

Gradual clearing. Occasional drizzle and mist will persist into tonight, with fog in some areas. Lows will be in the upper 40s to near 50°. Considerable cloudiness in the morning will yield gradually to sunshine in the afternoon tomorrow with highs around 66°.

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

Opera on the Mall

Today's WaPo reports ("Puccini to Give You the Shivers") on yesterday's remote broadcast of the Washington National Opera's performance of Puccini's Madama Butterfly using a giant screen on the Mall. Compared to the estimated 13,000 who attended last year's al fresco performance of "Porgy and Bess", the WaPo counted between 200 and 300 hardy opera lovers who braved the elements yesterday.


The podcast of Matt's discussion yesterday of the winter outlook on WeatherTalk radio has been posted on the show's website.

Seasonal Outlook

Latest seasonal forecast: Click here.

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