Matt-Regarding the potentially "strong" cold front on the weekend...does a spring cold front typically mean temps in the 50s (as indicated on Sunday)?

Yes, Missy, we can get pretty cool temperatures behind a spring cold front, particularly when this "cold air damming" sets up. (My condo may try to turn off the heat in a week or so. That's a bit too early!)

Jet stream is well north of us and weak. So, why are we still sitting in the crud? (There's a clue to this situation in the above paragraph! Just think CAD.)

First lightning strike within Canada, observed in SW Quebec. The most lightning seems to be in eastern OK at this time. There's also an isolated strike or two off the FL Keys.

The jet will be back over us Friday and Saturday. That's why some rain is back in the forecast with the passing cold front.

Crossing my fingers on Thurs / Fri. It is interesting the effect that the weather icons have.

For example, NWS for Thurs & Fri has a sun peeking out over some clouds for partly sunny... makes me feel pretty good. But CapWx just has a big blah gray cloud... which makes me want to sleep in.

Is it still too early to have an idea of what gametime conditions will be like Friday at Nationals Park? I'm waiting until Wednesday afternoon to determine whether to get tickets and hoping that the chance of rain gets pushed later and later.

Jake -- the icons in At A Glance are our icons, but they are driven by the NWS forecast (as per credit below forecast). For some reason, they are feeding us a forecast of Mostly Cloudy for Thu/Fri, even though the forecast you get from the NWS Web site is for partly sunny. We know these two forecasts come from different sources, though there should be a bit more agreement than that. Of course this is why there's always our more detailed forecast narrative to look at.

Mud Forecast?

Any thoughts on how much rain we'll get on Saturday? The Bull Run Run (on trails) is Saturday, and we're wondering how muddy things will get.

Here I am again, asking for somebody to explain some weather phenomenon in layman's terms...maybe that's my job on this comments board...

What causes this marine layer form over us periodically?

(I love this site!)

Oh, I know the source is the NWS. It's not a knock on the forecast itself -- just an observation on the icons.

Laura....typically we get this marine layer, or what is known as cold-air damming, when pressure is very high to the northeast of us and the outflow from it causes a east or northeasterly flow at low levels of of the Atlantic, where the water temperatures this time of year are much cooler than those on land. The low-level layer of cool, moist, maritime air is quite stable, often stays east of the mountains and soes not penetrate west, and usually produces fog, drizzle, or very light rain from stratus clouds unless a southerly flow of warm, moist, unstable air rides up over the top of it, producing showers and possible thunderstorms from cumulus clouds aloft. I have seen that happen...a cold 38 degrees and sleet/ice pellets (true sleet, not hail) at the surface with lighting (even cloud-to-ground)from thunderstorms aloft.

Mike, thanks for your explanation! I didn't catch on that the marine layer forming is typically the same thing as cold air damming. I think I've finally got a handle on it now.

Just one step closer to being able to read models....

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