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NOAA, National Weather Service Middle Atlantic River Forecast Center Briefing. 1:00PM, March 28, 2014. Key Message. Prolonged period of moderate to heavy rain is expected Saturday and Saturday night with amounts from 1-3 inches.
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NOAA, National Weather ServiceMiddle Atlantic River Forecast Center Briefing 1:00PM, March 28, 2014
Key Message • Prolonged period of moderate to heavy rain is expected Saturday and Saturday night with amounts from 1-3 inches. • Significant rises will occur on many rivers and streams with minor to moderate flooding possible at some locations. • Frozen ground, snowmelt where snow still exists, and dormant vegetation will result in enhanced runoff.
Timing of rain & flooding • Rain will overspread the region from south to north between 8pm Friday and 8am Saturday. • Rain may be heavy at times on Saturday and Saturday night. • Lighter rain will taper off during Sunday. • Across portions of New York and Northern/Central Pennsylvania, rain may change to snow before ending later Sunday.
Rain on the ground • Rainfall for the 24 hour period ending at 8AM, Friday March 28
Current Stream Conditions • Current streamflows generally range from below normal to normal across Pennsylvania and New York • Current streamflows generally range from normal to above normal across portions of New Jersey, Maryland, and Virginia.
Additional Rain • 1.5 to 3 inches of Rain across portions of MD, DE, NJ, eastern PA, southern and central NY • Heaviest Rain Saturday and Saturday Night
Flash Flood Potential • Less than an inch of rain in 3 hours is needed to cause Flash Flooding on some small streams and creeks.
Current River Forecasts • Minor flooding possible at some locations on Sunday/Monday • Slight risk of isolated moderate flooding if rainfall exceeds current forecasts. • River forecasts will be updated every 6-12 hours.
Uncertainty • Heaviest rainfall will likely form into narrow 10 to 30 mile wide bands. • Exact location and movement of these bands cannot be accurately predicted, so location of heaviest rain is still highly uncertain. • NWS will be closely monitoring developing storm and will issue updates throughout the weekend.
Remember • Radar rainfall estimates may not be accurate where there is hail, changeover to snow, at the freezing level, etc../ • MARFC graphics & info may not contain the entire flood threat. See info from your local weather forecast office for flash flooding, storm surge, river flooding in tidal reaches, etc..
Flood Safety Messages • Turn Around Don’t Drown. • Have a Plan, Lessen Your Loss. • Monitor the NOAA Weather Radio, or your favorite news source for vital weather related information. • Be especially cautious at night when it is harder to recognize flood dangers. • Monitor http://water.weather.gov for your river forecast. Look for frequent updates. Realize the uncertainty in river forecasts.
Need more info? • Contact your local NWS Weather Forecast Office • Binghamton, NY http://weather.gov/bgm • Blacksburg, VA http://weather.gov/rnk • Mt Holly, NJ http://weather.gov/phi • State College, PA http://weather.gov/ctp • New York City, NY http://weather.gov/okx • Sterling, VA http://weather.gov/lwx • Wakefield, VA http://weather.gov/akq • Email: peter.ahnert@noaa.gov
Find MARFC Online at: • Homepage: http://weather.gov/marfc (our website is having technical problems today, if this site isn’t working go to the AHPS pages to get our latest forecasts: http://water.weather.gov • Facebook: https://www.facebook.com/US.NationalWeatherService.MARFC.gov • Twitter @NWSMARFC • Hashtags: #NJWX, #DEWX, #MDWX, #PAWX, #VAWX, #NYWX, #WVWX
Next MARFC Briefing • 1:00PM Saturday, March 29