Timing Wednesday’s Potential Dangerous & Widespread Severe Weather Outbreak

030117_preliminary_severe_tstorm_risk_dcstorms-com

Many ingredients are coming into play on Wednesday afternoon for a potential widespread outbreak of Severe Thunderstorms across the Mid-Atlantic.

  • CAPE values are forecast to be running at nearly 1000 j/kg
  • Dew points are forecast to be in the 60s
  • Afternoon temperatures are forecast to soar into the middle to upper 70s
  • Helicity values (wind shear) are forecast to be high

The preliminary map above is based on the latest high-resolution models.

  • The big question mark in my mind this evening is whether or not left-over convection (thunderstorms) in the Midwest (seen in the image below) will actually impact the far northwestern zones (panhandle of West Virginia and Maryland) during the morning rush hour.  Any morning convection may dampen afternoon CAPE values across those areas as the main line of thunderstorms arrives in the afternoon. These areas are not out of the woods by any means but could keep the strongest storms a bit further south and east where daytime heating would reach its peak.

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Incoming Drought Relief this Evening &Timing Wednesday’s Thunderstorms

I took this picture of the gorgeous Japanese Tulip trees blooming in Arlington National Cemetery, in April of 2015 (@DCstorms)

The latest high-resolution models hold off on steady rain until the second half of this afternoon’s rush hour (6PM in downtown DC). I’m hoping the rain holds off until the end of the rush hour but regardless of timing we desperately need the rainfall as moderate drought conditions continue across portions of the Washington DC Area.

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