Valid 072000Z – 081200Z
…NO THUNDERSTORM AREAS FORECAST…
Thunderstorms are not expected through tonight.
No changes have been made to the ongoing forecast.
.PREV DISCUSSION… /ISSUED 1023 AM CST Fri Feb 07 2020/
…Mid Atlantic to Long Island in the short term…
A 975 mb surface cyclone, with an associated 175 kt jet aloft, will
continue to deepen while moving northeastward from the PA/NJ border
as of 15z to down east Maine by this evening. A narrow, remnant
warm sector (with surface temperatures 58-64 F and dewpoints in the
mid 50s) this morning from the Chesapeake region into NJ has
supported bands of low-topped convection along the primary cold
front. Lightning has diminished since earlier this morning as
convection has become shallower with time, as equilibrium level
temperatures have warmed to greater than -12 to -15 C. Surface
destabilization will be more limited farther northeast toward Long
Island, which suggests that the damaging-wind threat is now ending
as convection exhausts remaining warm sector buoyancy across NJ.
…Elsewhere through tonight…
The threat for additional lightning, other than sparse flashes
triggered by towers from northeast PA into New England, appears too
marginal to warrant a thunderstorm outlook area. Any thunderstorm
threat across southeast FL is also ending as the cold front moves
offshore. An upstream shortwave trough will move inland over WA
this evening and the northern Rockies overnight. Relatively steep
lapse rates will accompany this trough, but cool/cold profiles will
limit buoyancy and the threat for thunderstorms.