Getting Better All the Time

This afternoon's weather map shows a cool, dry high pressure area centered over southern Canada and dominating the entire Atlantic coast. Despite the northerly breeze veering somewhat easterly at times, the entire Washington metro region was enjoying sunny mid 60s temperatures by mid afternoon. Even the Bay and Eastern Shore locations were mainly over 60, although Ocean City was a brisk 57 with a northeasterly wind gusting to 26 mph. Today's models are unanimous in saying that Camden's earlier weekend assessment may have been a bit pessimistic; the sunny and dry conditions are predicted to continue right on through Sunday.

Surface weather map and satellite picture at 2pm today from HPC/NCEP/NWS

Tonight and Tomorrow

For tonight, clear skies and light winds should allow temperatures to drop to the mid 40s city, as low as the mid 30s in the colder 'burbs. Tomorrow earns the CapitalWeather.com Seal of Approval, although the high near 67 under sunny skies will be only marginally "room temperature".

Tropical Topics

As the clock ticks down to the beginning of another tropical season, the American Meteorological Society's 27th Conference on Hurricanes and Tropical Meteorology is winding up today in Monterey, CA. There have been a number of interesting presentations, especially on the controversial issue of the relationship between global warming and hurricane activity.

Colorado State University's Dr. William Gray, whose claim to fame appears to be mainly based on statistical forecasting, goes out on a limb with his strong denial of any connection. His presentation is certainly "in your face"; the introduction is a quote from an ideologically partisan oil-state senator and the closing is a statement from the public relations person of the American Association of Petroleum Geologists about a science fiction book. Gray's scientific assertions regarding the oceanic thermohaline circulation (THC) are thoroughly demolished at RealClimate.org, where a spirited discussion has generated over 60 comments in the last couple of days.

MIT Prof. Kerry Emanuel, author of the recent book Divine Wind, is a joint author with two researchers from the University of Miami of a paper, Could hurricanes form from random convection in a warmer world?. This study uses physical modeling to assess whether increases in sea-surface temperatures could induce spontaneous generation of hurricanes without the usual prerequisites.

Abstracts for all the conference presentations, as well as many extended versions with graphics, are available on the conference web page.

FEMA Found FUBAR; Weather Not

Yesterday's cloud-enhanced chill in the Washington DC metro area has been replaced by much more seasonable readings. Wednesday's official high of 59° was the lowest since the 57° on the 9th, but nearly all locations were at or above 70 by mid afternoon today ahead of a cold front bringing a reinforcing shot of cooler air for tomorrow.

CapitalWeather.com chart from NWS data, photo ©
Kevin Ambrose

Tonight and Tomorrow

Tonight will be variably cloudy with lows from the upper 40s to near 50 in the city and lower 40s in the cooler 'burbs. Tomorrow will be mostly sunny with highs around 66, but northeasterly winds could bring in more clouds and cooler temperatures east of the immediate metro area.

Preparedness Disaster

The AP reports via the online WaPo that the Senate Committee on Homeland Security and Governmental Affairs has recommended that FEMA be abolished and replaced by a National Preparedness and Response Authority. The committee report concludes that

1) long-term warnings went unheeded and government officials neglected their duties to prepare for a forewarned catastrophe; 2) government officials took insufficient actions or made poor decisions in the days immediately before and after landfall; 3) systems on which officials relied on to support their response efforts failed, and 4) government officials at all levels failed to provide effective leadership.

Notice the emphasis on the fact that the catastrophe was "forewarned". The meteorological community, and especially the staff members of the National Hurricane Center, can take pride in the recognized excellence of the forecasts leading up to the storm's landfall. The report singles out the "strongly worded advisories from the National Hurricane Center (NHC) and personal warnings from NHC Director Max Mayfield".

Meanwhile, Reuters reports that the White House is opposed to the committee's recommendation that FEMA be scrapped. Hurricane season officially begins in 34 days.

Dry Afternoon; Liquid Likely Later?

The rain associated with a strong cold front and a weak low pressure area approaching from the Ohio Valley had made it only as far as the Pittsburgh area by mid afternoon today. Current indications are that showers will continue to develop along the front, but any rain in the Washington metro area is likely to hold off until the low pressure area swings eastward through central Virginia late this evening. If you're headed outdoors this evening, bring rain gear, but there is a good chance that the Nats game will be dry until at least the late innings. The NatCast has been adjusted to reflect the later arrival of precipitation. For the outlook the rest of the week, see Matt's post below.

Drought Busters

The weekend's rain went a long way toward relieving the drought in the Washington DC area. The map of the Maryland/DC/Virginia area, from the National Weather Service's experimental Precipitation Analysis, shows the rainfall for the 24 hours ending at 8am Sunday. There was a wide variation across the area, from the merely generous to the nearly stupendous. Notice the southwest-to-northeast banding structure, with the heaviest amounts both northwest and southeast of the District. As Jason explained earlier, showers and thunderstorms are likely late tomorrow, especially south of the Beltway, but the rest of the week looks quite fine.

Tonight and Tomorrow

Lows tonight under mostly clear skies will be from the low 50s in the city to the upper 40s in the colder 'burbs. Clouds will increase tomorrow afternoon with highs around 71. There is a 60% chance of showers and possibly thunderstorms late tomorrow afternoon through the evening, with higher amounts likely in the southern portion of the region.

Deficit Reduction

The above-average precipitation so far in April has reduced the accumulated yearly deficit from around 40% at the beginning of this month to 24% as of today. The chart shows the official observations at National; weekend rainfall at Dulles was over twice as high. At Dulles, nearly a month's normal rainfall fell in one day, but the total is still well short of the April monthly record of 7.35" set in 1973.

CapitalWeather.com chart from NWS data, photo © Kevin Ambrose

Capitol Climate

The American Meteorological Society's Environmental Science Seminar Series on Capitol Hill continues next week on May 3 with the topic, "Changes in Cold Places - A Look at the Greenland Ice Sheet, Arctic Sea Ice and the Antarctic Ice Sheet".

Hard Rain Gonna Fall?

Well, not yet, anyway. Despite a nearly stationary front lurking in the vicinity and juicy dewpoints for the season in the mid to upper 50s, rain showers have been slow to penetrate the drought-dogged DC metro area. I encountered a brief shower in the Shady Grove area of Rockville/Gaithersburg early this afternoon, but it was barely enough for a few swipes of the windshield wipers. National Airport reported less than half an hour of light rain in the 2-3pm hour; the total amount was a trace, and Dulles received the same amount. Radar at mid afternoon showed some showers generally eastward from near Charlottesville across the Northern Neck and up and down most of the Eastern Shore.

Live radar loop above, courtesy WJLA. Refresh page to update.

Temperatures are holding in the mid 60s under easterly winds, although National was 2 degrees higher at noon with 67.

Mr. Model, the PM edition, (or at least the first one out of the gate) is still insisting on getting some rain onto the ground by 8pm tonight, but from the looks of things right now, the best chance for some drought-denting, if not drought-busting, rain in the next 36 hours looks like the period from late morning Saturday through Saturday evening. The heaviest amounts, however, are predicted to the northwest of the District. The graphic to the right shows the model forecast of the 12-hr precipitation ending at 8pm Saturday. The amounts in blue range up to 1.25"

Tonight and Tomorrow

Lows tonight under overcast skies will be in the mid to upper 50s. The chance of showers will increase from 60% through this evening to near 100% by tomorrow morning. The best chance of showers this evening is southeast of the Beltway. Showers and possibly thunderstorms are likely tomorrow with highs in the mid 60s.

Which Way the Wind Blows

Regular readers may recall that we remarked last year on the fact that Bob Dylan's music is heavily influenced by weather imagery. Yesterday's WaPo Reliable Source column revealed that Dylan's debut as a disc jockey on DC-based XM Satellite Radio May 3 will feature an hour of weather-related music. Some of the tunes, according to the Reliable Sourceresses, include: Muddy Waters's "Blow Wind Blow," "Just Walkin' in the Rain" by the Prisonaires and "Place in the Sun" by Stevie Wonder. The XM press release gives some more details, including the fact the Stevie Wonder tune is sung in Italian. Track lists will be posted on a special Bob Dylan web page on the XM site.

No-protest Weather Running Out

There was nothing to protest about the weather for the Chinese president's visit to the Nation's Capital today. The string of exceptionally fine spring days was extended with temperatures at or above 80 by mid afternoon throughout the metro area.

As Josh explains below, however, our luck will be running out starting tomorrow. A low pressure area moving northeastward from the Tennessee Valley will bring clouds and the threat of showers by mid-day tomorrow, along with significantly cooler temperatures.

Photo of brilliant blue sky over Georgetown yesterday by CapitalWeather.com photographer, Kevin Ambrose.

Tonight and Tomorrow

Increasing high clouds tonight will keep low temperatures in the upper 50s city to the low 50s in the colder 'burbs. Skies should be overcast by tomorrow morning with showers arriving by early afternoon and continuing into tomorrow night. There is an 80% chance of showers and possibly thundershowers by evening; highs will be in the upper 60s.

Above-Average April

As Matt noted a couple of days ago, this month so far is another in a long series of warmer than normal months. The chart shows that only 5 of the daily highs and 4 of the daily lows out of 19 days have been below the long-term average.

We are now rapidly approaching the point in the year at which freezing temperatures have never been observed. This Sunday, with a record low of 33, is the earliest such date. On the high side, 95° seems to be some kind of cap for April. That reading has been reached on 4 different dates, including as early as the 17th, but never exceeded.


CapitalWeather.com chart from NWS data, photo © Kevin Ambrose

Not-too-taxing Weather (Unless You're a Plant)

Temperatures are at outstandingly pleasant seasonal levels in the Washington DC metro area this afternoon, mainly upper 60s by mid afternoon and a few 70s on the southern fringes of the region. As Matt indicated earlier, this fine spring weather is likely to continue for several more days.

Although heavier amounts fell to the south, the modest rainfall yesterday barely made a dent in the accumulated precipitation deficit. Dulles received only 0.25" vs. the 0.35" at National, and BWI had a mere 0.01". Here in the northern suburbs, about half the official amount fell at the local WeatherBug network station.

CapitalWeather.com chart from NWS data, photo © Kevin Ambrose

Tonight and Tomorrow

With clear skies and light winds, low temperatures tonight will be near 50 in the city, down to the lower 40s in the colder 'burbs. Tomorrow will look a lot like today, but a couple of degrees warmer, highs near 73.

See CC TV

Earth Day is approaching this Saturday, and PBS has climate change on the schedule for tonight. As PM Update previewed yesterday, NOVA is presenting "Dimming the Sun", based on a BBC program broadcast last year. Last night, RealClimate.org posted a new entry noting that the NOVA version has been re-edited, hopefully to remove or put into better context some of the more extreme claims.

NOVA is immediately followed by "The State of the Planet's Wildlife", another program in the "Journey to Planet Earth" series. This program, narrated by Matt Damon, focuses on the effects of climate change on wildlife and the threat of widespread extinctions.

On Saturday, HBO is broadcasting the documentary "Too Hot Not to Handle", produced by Laurie David, wife of Larry David. All three shows are previewed in today's New York Times.