A flood warning is in effect across the Baltimore region after an inch and a half of rain fell Thursday night into Friday morning, but some clearing and sunshine are expected Friday afternoon.
The rain gauge at Baltimore-Washington International Thurgood Marshall Airport measured 1.49 inches of precipitation from 9 p.m. Thursday through 10 a.m. Friday.
A line of downpours that moved through the region late Friday morning brought the heaviest rainfall, with 0.48 inches of rain at BWI from 9 a.m. to 10 a.m.
The National Weather Service issued a flood warning for the Baltimore region through 4 p.m., saying that as much as 2 inches of rain had already fallen in some areas as heavy downpours moved through.
"Streams are already elevated from earlier rain, so the heavy rain will cause flooding of small streams and urban areas," forecasters said.
But as the low-pressure system responsible for the rain moves northeast, a gradual clearing is forecast by midday Friday and into the afternoon. That's because the zone of the storm system known as a "dry slot" will be overhead — an area of dry air in its southwest quadrant.
That is likely to mean periods of showers into the early afternoon, but possibly some sunshine, too. Heating from that sunshine could trigger afternoon or evening storms, forecasters cautioned. Highs are forecast in the mid-70s.
Another line of showers is forecast to move through Saturday.
Clearer skies are expected Sunday, but with cool and breezy conditions. Highs are forecast in the lower 60s with 10-15 mph breezes and 20-25 mph gusts.
Temperatures may stay stuck in the 50s Monday, and highs are otherwise forecast in the lower 60s early next week.