WPC Met Watch |
|
Mesoscale Precipitation Discussion: #0830 (2019) |
(Issued at 957 AM EDT Thu Sep 05 2019
) |
|
MPD Selection |
|
|
|
Mesoscale Precipitation Discussion 0830
NWS Weather Prediction Center College Park MD
957 AM EDT Thu Sep 05 2019
Areas affected...Coastal SC and NC
Concerning...Heavy rainfall...Flash flooding likely
Valid 051356Z - 051956Z
Summary...Heavy rainfall associated with Hurricane Dorian will
continue to rotate onshore across coastal South Carolina and North
Carolina today. A prolonged period of 0.5 to 1.5" hourly totals
with isolated hourly totals up to 3" will likely lead to flash
flooding, with some significant flash flooding possible.
Discussion...Several rain bands associated with Hurricane Dorian
have been rotating onshore from coastal South Carolina through
coastal southeastern North Carolina this morning. So far through
10 AM EDT, totals of 5-7" between CHS and MYR have been reported.
Current radar imagery shows rain rates from KTLX to be between
1-2"/hr across northeast coastal SC and southeastern NC.
The 12Z upper air sounding from MHX showed a PWAT of 2.02", around
1000 J/kg of MUCAPE, and a warm cloud depth of approximately
15,000 ft - all indicators of a tropical, efficient rain producing
air mass. The latest mesoanalysis showed the greater surface-based
instability across southeastern NC and extreme northeastern SC
with values of around 1000-1500 J/kg. This area will be conducive
to hourly rain totals between 2-3" as rain bands continue to
rotate onshore. Across coastal South Carolina, with the storm
tracking nearly parallel to the coast, this will lead to a very
prolonged period of training heavy rainfall generally along and
east of I-95. Through 20Z, there is high consensus in the latest
hi-res model suite for widespread 3-5" with locally higher amounts
between 7-8" totals across coastal South Carolina northward across
southeastern North Carolina.
Flash flooding will be likely throughout today, with the risk
spreading northeastward from coastal SC through eastern NC during
the day. The greatest potential for significant flash flooding
will be found across across coastal SC and southeastern NC where
the combination of intense rain rates and duration overlap.
Taylor
ATTN...WFO...CAE...CHS...ILM...MHX...RAH...
ATTN...RFC...SERFC...
LAT...LON 35467698 34987625 34697646 34657666 34557732
34057786 33857812 33787856 33447905 33217925
32807978 32528019 32378062 32918069 33658041
34298002 34597937 35017849 35057840 35457771
Last Updated: 957 AM EDT Thu Sep 05 2019
|