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FLOOD WATCHES: Another Round Of Heavy Rain

Here We Go Again, Flooding Threats
Posted at 10:51 PM, Dec 19, 2018
and last updated 2018-12-20 16:32:00-05
Soggy Timetable

Here we go again another Flood Watch and even the chance for some severe weather. We continue to add on too our yearly record breaking 68+ inches of rain in Baltimore with another 1-2"+ of rain forecast for Thursday afternoon into Friday. Besides the water aspect to the storm system we look to deal with wind. Winds could easily gust 30-40 mph Friday into Saturday with 50 mph gusts down at the Maryland beaches.

TIMING

A Flood Watch is in place for Harford, Anne Arundel, Carroll, Howard, Baltimore, Baltimore City, Frederick, Washington, Montgomery, Charles, Calvert, St Mary's, Kent, Queen Anne's and Prince Georges counties from Thursday afternoon into Friday evening. A watch means that conditions are favorable for flooding with 1-2" of rain in the forecast and the possibility of 2"+ in localized areas.

Flood Watch Thursday-Friday

Rain is set to arrive late Thursday afternoon from southern Maryland before pushing north into Baltimore for the evening rush hour commute home. Heavy rain and even a few rumbles of thunder look to arrive overnight Thursday into early Friday morning. This will be our best bet for flooding before a break in the action early Friday afternoon. Another round of heavy rain moves in Friday evening accompanied by gusty winds and a changeover to snow in the mountains of Maryland come early Saturday morning.

Storm Setup

Once again two areas of low pressure are responsible for the super soaking. One will track up the mountains the west and another off the coast. Both will gather rich Gulf of Mexico and Atlantic moisture hence the prolonged rain train Thursday through Saturday morning.

Rain Arrives
Heavier Rain Sets In

The worst of the rain though looks to come in Thursday night with the best chance of flash flooding throughout the overnight period and then again Friday morning. Low pressure will skirt east of the the region Friday afternoon giving us additional lift for the rain/wind threat to continue. Models continue to hint on a solid shield of rain Thursday evening through Friday morning with a lull midday Friday before another rainy slug Friday evening through early Saturday morning.

Late Night Storms
Cold Front Passes

BALTIMORE/I-95 CORRIDOR IMPACTS

Many locations look to receive 1-2" of rainfall with localized pockets of 3"+ closer to the I-95 stretch. Wind gusts upwards of 20-30 mph with any thunderstorms that may form. Urban street and stream flooding likely. Areas of concern based on recent rain Howard County (Patapsco River) and Montgomery County.

Local Rain Amounts
Friday Morning Winds

EASTERN SHORE/KENT ISLAND/ANNAPOLIS/CECILTON

1-2" rainfall amounts with localized areas of 3" or more. Heavy ponding on the roads with urban street and small stream flooding. Minor to moderate coastal flooding concerns as winds come in from the east piling the water up into the Chesapeake Bay. Wing gust 30-40 mph with isolated severe weather concerns south of US-50.

Regional Rain Swath

SOUTHERN MARYLAND/OCEAN CITY/SALISBURY

2-4" rainfall amounts with winds gusting 50-60 mph down along the coast Friday into Saturday. Low end severe weather risk with an isolated tornado south of MD 92.

Thursday's Severe Threat

MOUNTAIN MARYLAND/FREDERICK COUNTY POINTS WEST

1-2" of rainfall with localized heavier pockets. Concerns for flooding along the Potomac as well as back toward Tow Creek near Cumberland. Winds gusting 20-40 mph with 50 mph gusts above 2500ft. Snow showers late Friday night into Saturday. 1-3" of snow accumulation above 2,000 ft. Best snow accumulations from Frostburg back toward Deep Creek/Oakland/Friendsville.

Upslope Snow Saturday

The time is now to think about your flooding precautions. If you live in a low lying area remember to seek higher ground when a warning is issued. Never drive through high water since you may not know what is underneath of it or in it. The old saying "Remember Turn Around Don't Drown." A common saying that oh so many do not listen too. Please do not take it for granted since these situations look to change very quickly.

7 Day Forecast

Rain is out Saturday mid morning with clearing skies and temperatures in the 40s. Next shot of precip comes Christmas afternoon with a chance of flurries and highs in the low 40s.