PM Update: Heavy rain possible Saturday, flood watch; dry Sunday

* Flood watch Saturday morning through evening *


Radar & lightning: Latest regional radar shows movement of precipitation and lightning strikes over past two hours. Refresh page to update. Click here or on image to enlarge. Or see radar bigger on our Weather Wall.

Precipitation of the frozen kind is safely in our rear view window, but a raw cold rain persists overnight. Saturday temperatures take a big bounce up, but heavy downpours limit the amount of available outdoor time. Sunday’s the better of the two days for outdoor plans, though a bit breezy and cooler.

Through Tonight: Periods of light rain are likely, especially early on. We might get a break after midnight, though it will remain cloudy. Temperatures are near steady – around 40 degrees. Winds are from the south and southeast at 5-10 mph.

Tomorrow (Saturday): If we see a break in the rain and even some breaks in the cloud cover, it’s in the morning hours. Strong southerly flow boosts temperatures through the 40s and 50s by early afternoon, to around 60. During the afternoon, rain chances increase to near 100 percent, with the possibility of heavy showers and perhaps a rumble of thunder or two. A quick 1-2 inches of rain may fall – with the most likely window of heavy rain between 2 and 6 p.m. “This heavy rain will combine with cold and wet soils to elevate the threat of flooding,” says the National Weather Service in its flood watch statement. Winds are from the south at 10-15 mph, but we might see some stronger gusts in showers and thundershowers.

High resolution NAM model radar simulation shows heavy rain moving into D.C. area around 2 p.m. (WeatherBell.com)

High resolution NAM model radar simulation shows heavy rain moving into D.C. area around 2 p.m. (WeatherBell.com)

Saturday night: Rain showers are likely in the evening, but should end between 6 and 9 p.m. Skies than gradually clear, with lows 35-40 (coldest in the north and west suburbs). Winds become out of the west at around 10 mph.

Sunday: This is not a bad day at all for mid-January. Skies are mostly sunny, and highs climb up to near 50 degrees. There will be a bit of breeze from the west (10-20 mph), which will make it feel chilly especially when you step out of the sun.

See Camden Walker’s forecast into early next week. And if you haven’t already, join us on Facebook and follow us on Twitter . For related traffic news, check out Dr. Gridlock.

River flood risk map for the weekend (Mid-Atlantic River Forecast Center)

River flood risk map for the weekend (Mid-Atlantic River Forecast Center)

River flooding/ice jam risk: The Mid-Atlantic River Forecast Center is highlighting the potential for river flooding this weekend due to heavy rain, warming temperatures, melting ice and possible ice jams. The threat for ice jams is more to the north and northeast of the D.C. area rivers, towards Pennsylvania and New Jersey. The Delaware and Susquehanna rivers, for example, face an ice jam risk. Link: Ice be jammed: Frozen river thaw, heavy rain could pose serious flood threat for N.J.

For the Potomac, Shenandoah and other local rivers, the ice jam risk is fairly low says the National Weather Service office in Sterling:

REGARDING RIVER ICE…VIRTUALLY ALL THE GAUGES THAT WERE SHOWING ICE EFFECTS YESTERDAY APPEAR TO HAVE THAWED DESPITE TEMPERATURES ONLY BEING SLIGHTLY ABOVE FREEZING THE LAST COUPLE DAYS. THE EXCEPTIONS ARE IN AREAS OF LOW FLOW…BUT THOSE ARE UNLIKELY TO POSE A FLOOD THREAT. SOME MINOR WITHIN-BANK RISES HAVE BEEN OBSERVED AND WILL CONTINUE TO BE POSSIBLE DUE TO ICE EFFECTS…BUT ICE-RELATED FLOOD POTENTIAL APPEARS LOW AT THIS TIME.

Also on Capital Weather Gang

After the warm-up, what next? A cooler trend mid-month, with snow chances increasing slightly