Heat Here, Humidity Not So Much (Yet)

Now

Sunny, very warm. Temperatures are once again in the very warm to hot range in the Washington metro area this afternoon with most readings from the upper 80s to around 90°. Leesburg was the local hot spot with 93° at 3pm. Although the humidity has crept upward, most dewpoints have remained in the low to mid 60s, which most people should find only marginally uncomfortable, especially with a persistent breeze around 10 mph.

Around noon, the NWS issued a Special Weather Statement regarding the threat for a few severe thunderstorms this afternoon and evening. Storm activity was expected to remain along and west of a line from Charlottesville to Frederick. Radar has confirmed the development of storms along the higher elevations, but so far they have remained generally west of I-81.

Tonight and Tomorrow

Very warm, more humid. Warm and increasingly humid conditions will continue through tomorrow. Lows under tonight's "blue" moon will be in the upper 60s to near 70° downtown and the mid 60s in the cooler 'burbs. Tomorrow's highs will be again in the upper 80s to near 90°. There is only a small chance of an afternoon or evening thunderstorm.

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

Tropical Topics: Weather Hazardous to Your Wealth?

In the Eastern Pacific, the last advisory has already been issued on ailin' Alvin, while Barbara is still expected to intensify, but to remain below hurricane strength. In the Atlantic basin, a Special Tropical Disturbance Statement was issued for a stormy area in the northwestern Caribbean and southeastern Gulf of Mexico.

The tropical forecasters from land-locked Colorado State have taken the opportunity of the official start of Atlantic hurricane season tomorrow to announce . . . absolutely no change in their storm numbers or intensity from the April 3 forecast. The above-average seasonal prediction got a lot of play on CNBC this morning, including Liz Claman with live coverage from the floor of the NYMEX commodity exchange, but the energy markets were apparently not impressed; crude oil and gasoline prices were both down. One commodity trader who was interviewed, however, was bullish on orange juice futures, especially considering that the size of the Florida crop has been cut in half over the last 2 years.

If you are interested in profiting from the hurricane season, the Chicago Mercantile Exchange has recently started a hurricane futures and options trading program covering 5 distinct geographic areas: Gulf Coast, Florida, the Southern Atlantic Coast, the Northern Atlantic Coast and the Eastern U.S.

For the lawyers out there, the preceding comes with no endorsement or guarantees from the management or staff of CapitalWeather.com.

Political Science

In light of the atrocities already committed in the War on Science being waged by the pollution industries and their political prostitutes right here in the fetid atmosphere of Spin City, it's hard to be surprised at anything these days, but the comments yesterday by the head of one of the two major government earth-science agencies were absolutely astonishing in their audacity. In an interview with NPR this morning, NASA Administrator Michael Griffin trashed the implications of the climate science being produced by his own agency and by most of the rest of the legitimate research community. In answer to host Steve Inskeep's question, "Do you have any doubt that this is a problem that mankind has to wrestle with?", the Administrator answered, "I am not sure that it is fair to say that it is a problem we must wrestle with." NASA climate scientist James Hansen told ABC News,

It's an incredibly arrogant and ignorant statement. It indicates a complete ignorance of understanding the implications of climate change.

Apparently, Griffin has other plans for Earth. If they haven't done so already, astronauts should be seriously considering whether they want to risk their lives riding in faith-based rocketships.

Summer Steadily Simmering

Now

Sunny, warm. It's nowhere near the record hot May of 1991 (see Today in Weather History), but temperatures continue to trend toward closing out May on a summery note. Afternoon readings are only a degree or two warmer today than yesterday, but humidity is gradually on the rise. Dewpoints, aided by a more southerly breeze, have inched up through the 50s to near 60°.

The only showers on radar are widely scattered along the central portion of the Virginia/West Virginia border.

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

Tonight and Tomorrow

Very warm, increasing humidity. Lows tonight under mostly clear skies will be in the mid 60s in town to near 60° in the 'burbs. Tomorrow will be sunny, warm, and a little more humid, highs 87-91°. Precipitation chances from all models are almost unanimously in the single digits through tomorrow evening.

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

Tropical Topics

Tropical Storm Alvin in the eastern Pacific was declared tropically depressed overnight. It continues weak, although convection increased somewhat this morning. It is expected to dissipate gradually within about 4 days.

Meanwhile, the second depression of the eastern Pacific season has become Tropical Storm Barbara. Unlike Alvin, Barbara is both closer to the coast and expected to intensify in the next several days to hurricane strength. Areas along the southeastern Mexican and Guatamalan coast have been advised to monitor developing conditions.

This is only the third time that 2 named storms have been observed during May in this region. The other years were 1956 and 1984.

High and Dry

Now

Sunny, warm, low humidity. The situation is not nearly as dire as the far Southeast, where drought conditions and some extensive wildfires prevail, but the Washington DC region's warm, dry spell is entering another week. Skies are essentially cloudless east of the mountains from Pennsylvania through Virginia. Temperatures in the metro area at mid afternoon were in the low to mid 80s, and humidity was in the comfortable range with dewpoints mainly in the low 50s and even a few upper 40s.

90-day precipitation chart from HPRCC/NOAA

Tonight and Tomorrow

Mostly clear, pleasant. Under clear skies and a nearly full moon, lows tonight will range from near 60° in the city to the low and mid 50s in 'burbistan. Tomorrow should be much like today: sunny and warm with comfortable humidity and highs 83-87°.

Tropical Topics

The National Hurricane Center is issuing advisories on Tropical Storm Alvin, the first named storm of the Eastern Pacific season. The storm, which has peak winds of 35 kt with gusts to 45 kt, is moving westward well off the coast of Mexico and is not likely to be any threat to land.

Mediarology

The PBS science series NOVA is repeating tonight a 2003 show featuring the unique 6 climatic zones of Mount Kilimanjaro. (Channels 22 and 26 at 8pm).

In recognition of the official start of hurricane season, The Weather Channel begins Hurricane Week this weekend. The featured Happening Tomorrow (9:30pm Sunday): Miami gets blown away by a major hurricane.

Gradual Warmup Continues

Now

Sunny, warm. This afternoon's weather map shows a strong high pressure area dominating the eastern third of the U.S. with virtually no rain anywhere east of the Mississippi. The Washington metro area is enjoying temperatures generally in the low 80s with only slightly higher humidity indicated by dewpoints reaching into the upper 50s. The warming trend is likely to continue into the holiday weekend.

Tonight and Tomorrow

Mostly clear, warm. Lows tonight under mostly clear skies will range from the low 60s downtown to the mid and upper 50s in 'burbville. Tomorrow will be sunny and a little warmer, highs 84-87°.

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

Tropical Topics

With the official start of hurricane season a week from tomorrow, the USAT Weather Guys had a pointer yesterday to an interesting collection of tropical cyclone climatology charts at the National Hurricane Center website.

The statistical return period for Category 1 hurricanes in the Mid Atlantic area, shown to the right, is 5 years for the Outer Banks, but 15 years for Virginia Beach and 24 years for Ocean City. Also included on the web site are maps of the actual total number of strikes by county for the last 80 years. The strike data is derived from an NHC technical memorandum which is available for download from the National Hurricane/Tropical Prediction Center library. Caution: These mainly pre-WWW documents were apparently scanned into pdfs which means that they have multi-deca-megabyte file sizes (multi-hour downloads on a dialup connection).

Graphic from NOAA/NWS/NHC

Programming Note: PM Update will be taking a long weekend, so have a great holiday, everyone!

Carbon Copy, Carbon Copied

Now

Sunny, warm. Temperatures are a degree or two warmer, high clouds are a little more prevalent, and there are a few more scattered showers along the Virginia/West Virginia border, but today is pretty much a carbon copy of yesterday weatherwise. Temperatures are mostly in the upper 70s with a couple of 80°+ readings in the warmer spots.

Continued seasonably warm and dry conditions are on tap through the end of the week and into the holiday weekend.

Tonight and Tomorrow

Mostly clear, warm. Tonight's moonlit skies will be accompanied by lows near 60° downtown to the mid 50s in cooler 'burbalonia. Tomorrow will feature lots of sunshine, only slightly more humidity, and highs 79-83°.

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

Climate Corner: More Carbon Copied

A paper, "Global and regional drivers of accelerating CO2 emissions", published yesterday in the online edition of the Proceedings of the National Academy of Sciences (PNAS), reports that worldwide CO₂ emissions have been increasing at an accelerating rate. The annual rate of increase for the first half of this decade was 3.1% per year compared to 1.1% per year for the 1990s. This rate was "greater than for the most fossil-fuel intensive of the Intergovernmental Panel on Climate Change emissions scenarios developed in the late 1990s."

News of this research appeared on page 1A of USAT ("Global carbon levels spiraling") and also in:

• SeaTi ("Scientists report rise in levels of carbon dioxide")
• UK Guardian ("CO2 emissions rise outpaces worst-case scenario")
• ChriSci Monitor ("Global carbon emissions in overdrive")
• Non-carbonated WaPo ("World CO2 emissions speed up since 2000")

Graphic from PNAS

DC: Delightfully Comfortable

Now

Sunny, warm. Southerly breezes have brought temperatures a few degrees warmer this afternoon, but humidities are still comfortable as dewpoints remain in the low 50s. Culpeper and Fredericksburg were the warm spots in the region with 81° at 4pm. Except for a few isolated popup showers near the southern portion of the Virginia/West Virginia border, radar is clear in all directions.

Continued seasonably warm and dry conditions are on tap for the next couple of days.

Tonight and Tomorrow

Mostly clear, seasonable. Lows tonight under a few scattered clouds will be from the upper 50s downtown to the low 50s in the 'burbs. Tomorrow will be a lot like today with highs in the upper 70s to near 80°.

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

Tropical Topics

The National Hurricane Center and Climate Prediction Center today issued the official outlook for this year's hurricane season. The forecast calls for a 75% chance of above-normal activity, including 13-17 named storms, 7-10 hurricanes, and 3-5 major hurricanes (category 3 or higher). Among the factors expected to contribute to the higher activity are: warmer sea surface temperatures, reduced wind shear, and lower surface pressure over the tropical Atlantic, higher upper atmosphere pressure from the central Atlantic eastward to Africa, and a favorable African easterly jet.

Hurricane season outlook graphic from NOAA.

Capitol Climate

Among the climate-related hearings scheduled this week on Capitol Hill is "Potential impacts of global warming on recreation and the recreation industry" by the Senate Environment and Public Works committee on Thursday.

The tentative topic for the next American Meteorological Society Environmental Science Seminar Series the week of June 11 is "Why Should We Trust that the Science of Global Warming is Right?".

As You Like It

Now

Sunny, comfortable. The allergy sufferers and gardeners may have some complaints, but for most people it's a nearly perfect May afternoon in the Washington metro area. Following an overnight cold frontal passage, it took until after 1pm to exceed the midnight temperature of 70°, but by mid afternoon low and mid 70s were widespread throughout the region. Radar is clear for hundreds of miles in all directions.

After similar temperatures tomorrow, a warming trend should set up for the rest of the week.

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

Tonight and Tomorrow

Partly cloudy, seasonable. Under mostly clear to partly cloudy skies tonight, lows will range from the mid 50s downtown to the upper 40s in the coolest 'burbs. Tomorrow will be much like today with highs in the low to mid 70s.

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

A Sinking Feeling

As you may have heard recently, some modelling studies have suggested that the Southern Hemisphere ocean may slow the rate of global warming by being a better CO₂ sink than earlier expected. You probably won't hear it from the more rabid blogs, squawk radio, or "Fair and Balanced" cable noise networks, but last week a study in the journal Science based on actual measurements indicated that exactly the opposite appears to be taking place. The data show that the capability of the Southern Ocean to absorb excess CO₂ may be already maxing out. The research was reported by the Beeb, the Guardian, and Reuters, among others.