Area forecast discussion
National Weather Service Columbia SC
200 am EDT Monday may 20 2013
Synopsis...
weak upper level trough will cover the region through Tuesday.
This will bring a high chance of showers and thunderstorms to the
area through at least mid-week.
&&
Near term /until 6 am this morning/...
upper trough is moving east and convective activity continues
to decrease. Still a little bit of activity in the far north and
far northeast though. Will continue low chances for the rest of
the night. Upper trough remains over the area and with
instability weak to moderate chance probability of precipitation appear appropriate. Main
threat heavy rain due to high precipitable water around 1.8 inches
and slow movement/deep warm cloud. Cloud cover lingering overnight
will generally keep overnight lows in the middle to upper 60s.
&&
Short term /6 am this morning through Wednesday night/...
the main upper trough is prognosticated to continue tracking slowly eastward
into Tuesday. Ridging behind the trough may be able to take hold
enough by Tuesday to bring lower rain chances. Until that time
just chance probability of precipitation Monday. Activity should become more diurnal in
nature Monday night and Tuesday night with a decrease in moisture.
Not expecting anything severe with the storms...just occasional
lightning and some heavier rainfall. Temperatures Monday and
Tuesday will be dependent upon amount and thickness of expected cloud
cover...along with rainfall areas. Mondays temperatures only
forecast to reach the upper 70s across the northeast...while the
csra may be able to climb into the lower 80s. Tuesday and
Wednesday may see a little more sunshine...so highs expected to be
able to climb into the middle and upper 80s once again. As for
overnight lows...readings mainly in the 60s.
&&
Long term /Thursday through Sunday/...
the region will be under the influence of a deepening trough
takes hold across the Mississippi and Ohio Valley regions of the
country. Rain chances increase slightly into Friday as the main
upper trough moves eastward towards the forecast area. Expect
mainly diurnal showers and thunderstorms through Friday night.
Once we move into the weekend...a dry surface wedge pattern
appears to take shape as the upper trough moves offshore. The
weekend may shape up to be dry. As for temperatures...expect them to
remain with highs in the 80s and lows in the 60s.
&&
Aviation /06z Monday through Friday/...
complicated and low confidence forecast this period. Abundant low
level moisture again overnight favors increased chances of stratus
or fog. Guidance again in agreement showing MVFR/IFR ceilings
developing overnight. Given terminals received significant rainfall
yesterday and dewpoint depressions are already low will mention
MVFR/IFR restrictions during the early morning hours today.
Think stratus will be more favored given abundant cloud cover and
cae vwp indicating a 25-30 knot low level jet. Will include
restrictions generally 07z-13z with improvement during the middle
morning hours Monday. Winds will be light southeasterly to calm
overnight increasing to around 5 to 7 knots from the south after
17z. Isolated convection again possible during afternoon heating
with ogb/cae/cub most likely to be affected but confidence too low
to include at this time.
Extended aviation outlook...scattered showers and
thunderstorms...mainly afternoon and evening...possible through
Thursday. Late night/early morning fog/stratus may be possible as
well.
&&
Cae watches/warnings/advisories...
SC...none.
Georgia...none.
&&
$$
