Capital Weather Live

Always a human at the helm: Updated around-the-clock by Capital Weather meteorologists.

Happening now: Clouds are more numerous this evening as temperatures slowly fall through the 80s.

What’s next? Storm threat returns for Thursday; some storms may be strong late. A couple more storms possible Friday, then a mainly sunny weekend.

Forecast in detail

Tonight: Partly cloudy overall. There is a chance for a passing shower or storm, mainly after midnight. Dew points rising deeper into the 60s keep temperatures from falling too much, with lows mainly in the upper 60s and lower 70s. Confidence: Medium-High

Hourly Forecast | Pollen, Air & UV

Tomorrow (Thursday): More like midsummer as humidity levels rise again and dew points head for the upper 60s or so. Moisture plus heat, as a weak front works this way, means showers and thunderstorms are possible. Some storms could be strong to severe, especially from late afternoon through evening. Before the storms, highs reach the mid- to upper 80s. Rain totals could reach an inch or so in heavier storms, but amount only to a few tenths or less in many spots. Confidence: Medium-High

Tomorrow night: Showers and storms are possible through the evening. Partly cloudy overnight with lows in the mid-60s to near 70. Some patchy fog late. Confidence: Medium-High

A look ahead

Partly sunny on Friday as humidity remains on the high side. We could see a couple late-day storms, but probably not as strong or numerous as Thursday. Highs again in the mid- and upper 80s. Confidence: Medium-High

Lots of sun this weekend. Saturday may be mainly in the mid-80s. By Sunday, readings rise to a range of mid-80s to around 90. For now, it looks dry both days. Confidence: Medium

Up around or above 90 to start the work week on Monday. We could stay hot through much or all of it. Confidence: Medium

Today’s daily digit — 7/10: It could be worse. It could be better (see: the last few days). | 🤚 Your call?
The digit is a somewhat subjective rating of the day’s weather, on a 0-to-10 scale.

A dip in the jet stream and approaching cold front will encounter a steamy air mass in the Mid-Atlantic on Thursday. The result could be scattered strong to severe storms that are mainly capable of isolated damaging wind and large hail. Heavy rain and some flooding may also occur.

As such, the National Weather Service has issued a level 2 out of 5 severe storm risk for much of the area. A level 1 out of 5 is currently covers Southern Maryland. Some adjustments to these zones are possible as we get closer to storm time.

There could be a couple showers or a rumble passing by during the pre-dawn Thursday as moisture-filled air surges into the region with a warm front. Another shower could pass during the morning. The main severe weather threat arrives during the late afternoon and especially evening.

Scattered storms should develop to the west by mid-afternoon, with odds of storms elevated locally from about 5-11 p.m. This is on the late side for storms, so a shift to a bit earlier is also possible. For now, this seems to favor hit-or-miss activity rather than widespread severe weather.

Jeff Halverson, Capital Weather severe storm expert, notes it's a bit like other risks of recent, with potential for morning clouds and showers to disrupt the main threat. However, he said there is enough wind shear – changing winds with height – to support the potential for strong or severe clusters of storms.

The storms may also pose an isolated flash flood threat given high humidity with dew points approaching 70, somewhat slow movement, and the potential for activity to repeatedly pass the same location. It's one of those cases where some spots will see very little fall and others could pick up several inches over a short period.

The full Moon will nearly disappear into Earth’s shadow Thursday night during a deep partial lunar eclipse. At mid-eclipse, about 95 percent of the Moon’s disc will be inside Earth’s dark central shadow.

Skywatchers across nearly the entire U.S., except extreme western Alaska, will be able to see the eclipse. Unlike solar eclipses, which are visible from relatively limited areas of Earth’s surface, lunar eclipses can be seen across an entire hemisphere. And no special equipment is needed: While a solar eclipse can only be safely viewed with proper eye protection, you can look at an eclipsed Moon for as long as you want.

Lunar eclipses can vary widely in appearance as the Moon moves through Earth’s shadow. Its color and degree of darkness depend in part on how much dust, volcanic ash and other aerosols are suspended in the stratosphere. Sometimes the lunar disc nearly disappears; at other times, it can range from deep red to bright copper. The color is caused by sunlight filtering and refracting through Earth’s atmosphere. From the surface of the Moon, an observer would see a reddish ring of light surrounding Earth.

Earth’s shadow, projected into space, has two components. The penumbra is the lighter outer portion, where Earth blocks only part of the Sun as seen from the Moon. The umbra is the darker inner shadow, where Earth completely blocks the Sun.

The August full Moon is known as the Corn Moon or the Sturgeon Moon. Both names originate in Native American sky lore, reflecting the time of year when corn is ripe for harvest and sturgeon are abundant in the Great Lakes region.

As the Moon enters the penumbra, a subtle darkening will begin along its southeastern edge, gradually becoming more noticeable as the Moon moves eastward through the shadow. Once it enters the umbra, the darkening becomes much more distinct. After mid-eclipse, the process reverses.

For this eclipse, the Moon enters the penumbra at 9:22 p.m. Eastern time Thursday. It reaches the umbra at 10:33 p.m., with mid-eclipse occurring at 12:13 a.m. Friday. The Moon leaves the umbra at 1:52 a.m., and the eclipse ends when it exits the penumbra at 3:03 a.m.

In the DC region, cloud cover may pose a complication for viewing. Models project mostly cloudy skies during the eclipse but breaks in the clouds could allow for occasional viewing.

If you miss this one, a much smaller partial lunar eclipse will occur Jan. 12, 2028, when only about 5 percent of the Moon will enter the umbral shadow. The next total lunar eclipse visible from the U.S. won’t occur until June 26, 2029.

Jason Samenow contributed to this report.