Valid 021300Z – 031200Z
…NO SEVERE THUNDERSTORM AREAS FORECAST…
…SUMMARY…
Isolated lightning flashes may occur across parts of the central
California Coast today. Severe thunderstorms are not expected.
…Synopsis and Discussion…
An upper low more than 300 miles off the coast of northern CA this
morning will continue to move slowly south-southwestward today. A
shortwave trough to the southeast of the upper low will move over
the coast of central CA later this morning and afternoon. Mid-level
lapse rates are expected to remain very poor, but there may be just
enough elevated instability to support charge separation and
isolated instances of lightning along the coast.
Across the eastern seaboard, an upper trough/low will develop
east-northeastward through the period. Cold mid-level temperatures
(around -28 to -30C) will be noted beneath the upper low across
parts of NC into the Mid-Atlantic, but low-level moisture is
expected to remain very meager behind a prior cold front passage.
The potential for low-topped thunderstorms this afternoon beneath
the upper low currently appears too limited to include a general
thunderstorm area.
A surface cold front will continue advancing southward across the
southern FL Peninsula this morning. The 12Z sounding from MFL shows
multiple inversions and very poor lapse rates through mid levels,
and large-scale ascent above the surface will remain negligible.
Accordingly, the probability for thunderstorms along the front
appears less than 10%.
..Gleason.. 12/02/2019
$$