Alert (9am): Wilma now a Category 5 Hurricane. Minimum pressure estimated at 882mb -- the lowest on record in the Atlantic Basin. See Washington Post article:
Wilma Strengthens to Category 5 Hurricane. I'm sure Steve will have more on this in his afternoon update. Stay tuned.
ForecastLooking for a perfect October day? You've come to the right place. How does
mostly sunny with highs in the upper 70s sound? We'll even one-up yesterday's warm but breezy conditions with lighter winds at 5-10 mph (down from 15-20 mph yesterday afternoon).
After lows in the low-to-mid 50s
tonight, it turns partly to mostly cloudy and noticeably cooler
tomorrow, with highs in the mid-to-upper 60s. A few light showers are possible
tomorrow evening and during the overnight hours. An increased chance of shower activity is in the forecast for
Friday, when high temps will struggle to reach 60 degrees under overcast skies.
The
weekend looks cloudy and cool -- high temps 60-65 -- and possibly rainy. There's still a lot of uncertainty regarding our weather for late Saturday and Sunday, as the models are trying to get a handle on the track of
Hurricane Wilma and how the storm will interact with other weather systems in the Eastern U.S. As of press time, Wilma was a rapidly intensifying Category 2 storm. She is expected to reach Category 4
on her way to possible landfall along the western coast of Florida late Saturday.
An Odorous Wind |
The red icon marks the spot of the WSSC sewer waste dump site in Capitol Heights, Md., just across the District line. Image courtesy Google. |
According to the Washington Post, local officials have tracked the
source of a foul smell to a Washington Suburban Sanitary Commission sewer waste dump site in Capitol Heights, Md. The odor, which residents said "reminded them of rotten eggs, propane, methane and skunks," was first reported in Northeast Washington on Sept. 28.
Weather records show winds blowing from the northeast during the morning hours of the 28th, thus confirming that folks in Northeast D.C. were downwind of the odor source. It makes sense that the District, as opposed to Maryland, would have felt the brunt of the stench during the first part of October, as winds then were often from the east and north -- also the reason for our extended period of cloudiness and rainfall during that time.
Conflicting Stories Share Bad ScienceAs Steve
mentioned yesterday, the Washington Post
reported on a study predicting that global warming will cause an increase in extreme weather events, including less frequent but more intense rainfall. Scientific American, meanwhile,
details a NASA study that indicates a warmer climate would produce less rain.
While it's hard to say whether the two studies contradict each other, there is no question that both stories promote a common misconception regarding air and its capacity for moisture. In the Washington Post story, scientist Gerald Meehl is quoted as saying that precipitation will intensify because "the warmer air can
hold more moisture." Likewise, the Scientific American article says "researchers have cautioned that warmer global temperatures could increase the atmosphere's ability to
hold moisture."
The idea that warm and cool air "hold" different amounts of moisture is misleading -- many scientists and educators cringe every time they hear it. As explained in the
Bad Clouds section of the
Bad Meteorology Web site, there is plenty of room for moisture in air of any temperature. The difference between warm air and cool air is that molecules of water vapor move more slowly as air cools, thus making it easier for them to attach to each other and condense into precipitation.
October's Hard to BeatThe wonderful weather this week has made me realize how much I love October. In fact, I think October might be the best weather month here in the D.C. area. November through March are automatically disqualified because of the potential for cold and wintry precipitation (although I am a snowlover). And June through September are out due to heat and humidity. That leaves April, May and October. The whole "April showers" thing takes care of that month, while May flowers do nothing but make my nose runny and my eyes watery.
It just seems that October often presents us with nice stretches of dry and sunny weather, comfortable temperatures in the 60s and 70s, and an occasional shot of refreshingly crisp air. (Notice I've conveniently forgotten about the dreary first half of the current October.)
What's your favorite month?