Scientific Forecaster Discussion
fxus62 kchs 182018
Area forecast discussion
National Weather Service Charleston SC
318 PM EST Thu Jan 18 2018
cold, dry high pressure will build over the region tonight
before moderating temperatures occur this weekend into early
next week. A cold front will push through the area late Monday
into early Tuesday followed by dry high pressure through at
least Tuesday night.
Near term /until 6 am Friday morning/...
surface high pressure will continue to build into the southeast
tonight, while zonal flow persists aloft. Deep dry air will preclude
any cloud formation overnight, so clear skies will be the rule.
Clear skies combined with light winds will make for ideal
radiational cooling conditions. Low temperatures are forecast to
drop to the mid to upper 20s, highest closer to the coast and
at the beaches. Given winds should remain around 5 mph or below,
wind chills will remain above advisory criteria.
Short term /6 am Friday morning through Sunday/...
dry high pressure will prevail through the period. An upper
disturbance will likely move through Saturday night into Sunday but
this will just lead to some mid/high clouds. Temperatures will
moderate through the weekend, reaching above normal levels starting
Long term /Sunday night through Thursday/...
high pressure will prevail over the southeast United States into
early next week before a cold front arrives late Monday into early
Tuesday. Ahead of the front, southerly winds will help advect deep
moisture characterized by pwats around 1.3 inches to the southeast
and result in some cloud cover. This could limit overall heating
potential a few degrees, but temps are still expected to peak in the
upper 60s/lower 70s Monday afternoon. Chances of showers should then
spread over inland areas Monday afternoon/evening before advancing
to the coast with the cold front Monday night. Dry high pressure
will then return behind the departing front on Tuesday and persist
into the middle of next week. Temps will be slightly cooler behind
the front, but should remain a few degrees above normal. In general,
afternoon temps should peak in the lower 60s away from the immediate
coast. Overnight lows should dip to around 40 degrees inland and mid
40s closer to the coast. The next best chance of precip is possible
on Thursday as a low pressure system passes south of region.
Aviation /20z Thursday through Tuesday/...
VFR is expected through 18z Friday.
Extended aviation outlook: no concerns until late Sunday night when
moisture increases the risk for low clouds/fog and then low
quiet marine conditions are expected overnight as high pressure
continues to build into the region, and the pressure gradient
relaxes. Northwest winds this evening will back to the west
overnight, with speeds 15 knots or less. Seas will be 2 to 4
Friday through tuesday: no significant concerns although
conditions will deteriorate somewhat Monday/Tuesday as a cold
front affects the area.
the kclx radar is out of service until further notice. Repairs
are ongoing. Adjacent radars include: kltx, kcae, kjgx, kvax
The downtown Charleston observation site (chls1/kcxm) remains
out of service until further notice.