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Posted at 01:54 PM ET, 10/25/2012

Hurricane Sandy scenarios for Washington, D.C.

It’s becoming increasingly likely Washington, D.C. and the surrounding region will feel effects from Hurricane Sandy. The question becomes: how severe? Scenarios range from a historic storm with widespread damaging winds and flooding to just some blustery showers.

Based on current information, I think we have strong odds of experiencing major to severe impacts in the D.C. metro and surrounding region but a lesser blow is certainly possible.

Let’s walk through the range of possible conditions we’ll experience and their probability.

SCENARIO A: WORST CASE - DIRECT HIT, SEVERE IMPACTS (30 percent chance)


In this morning’s run of the European model, Sandy makes landfall along the southern Delmarva coast before moving west northwest directly over Washington, D.C. This is a worst case scenario. (StormVistaWxModels.com)
In this scenario, Sandy parallels the Mid-Atlantic coast before making a hard left turn, delivering a crushing blow to the Delmarva peninsula and southern New Jersey. Then storm then tracks due west directly over the Washington, D.C. area.

What we might expect:

* Rain likely begins Sunday morning and increases in intensity during the day. Winds also gradually pick up, becoming very gusty by evening.

* The heaviest rain and strongest winds occur late Sunday night into Monday afternoon, with widespread power outages. Peak sustained winds from 50-70 mph and gusts over 75 mph possible.

* Winds remain strong into Tuesday, gusting over 40 mph frequently.

* Rain and wind slowly taper off Tuesday or early Wednesday.

* Rainfall totals of at least 4-8”. Widespread flooding occurs in low lying areas and creeks/streams.

* Severe, possible historic coastal flooding for Maryland, Delaware beaches.

* Crippling snow possible at high elevations of western Maryland and eastern West Virginia, possibly 6-12” or more with tree damage, power outages.

SCENARIO B: INDIRECT HIT, MAJOR IMPACTS (45 percent chance)


This morning’s run of the Canadian model, with storm making landfall near New York City Monday night (MeteoCentre, Canada)
In this scenario, Sandy parallels the the Mid-Atlantic and Northeast coast just offshore before making a hard left turn towards coastal areas from northern New Jersey to southern Connecticut.

What we might expect:

* Chance of showers Sunday and Sunday night, becoming breezy.

* Steadier rain develops Monday into Monday night, possibly heavy at times. Winds also pick-up, becoming strongest Monday night into Tuesday morning, gusting over 50 mph at times, sustained at 35-50 mph. Scattered power outages.

* Wind and rain diminishes by late Tuesday or early Wednesday

* Rainfall totals of at least 2-4”. Some flooding in low lying areas and creeks/streams.

* Significant to severe coastal flooding for Maryland, Delaware beaches.

* Snow possible at high elevations of western Maryland and eastern West Virginia, possibly 6-12” or more Monday into early Wednesday.

SCENARIO C: GLANCING BLOW, MINOR IMPACTS (20 percent chance)


GFS model from early this morning, showing landfall of Sandy in eastern Maine at (StormVistaWxModels.com)
In this scenario, Sandy parallels the Mid-Atlantic and Northeast coast well offshore before making a hard left turn towards coastal areas in Massachusetts or even Maine.

What we might expect:

* Chance of showers on/off Sunday through Wednesday with best chance Monday and Tuesday.

* Becoming breezy Monday and Tuesday, with sustained winds of 20-30 mph, with some gusts over 40 mph. Isolated power outages.

* Minor to significant coastal flooding and beach erosion for Maryland, Delaware beaches.

* Chance of snow showers at high elevations of western Maryland and eastern West Virginia, with light accumulations possible Monday into early Wednesday.

SCENARIO D: OUT TO SEA, FEW IMPACTS (5 percent chance)

In this scenario, Sandy heads to the northeast and then east, sparing the East Coast from a direct hit.

What we might expect:

* Slight chance of showers Sunday.

* Breezy Monday-Tuesday.

* Minor coastal flooding and beach erosion for Maryland, Delaware beaches.

By  |  01:54 PM ET, 10/25/2012

Categories:  Latest, Tropical Weather, Winter Storms

 
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