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fxus62 kcae 170556 
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Area forecast discussion
National Weather Service Columbia SC
156 am EDT Tue Sep 17 2019

Synopsis...
it should be dry and hot again today with Hurricane Humberto
well off the southeast coast and moving farther out to sea and
high pressure in the forecast area. A cold front will sink
southward and move through the area tonight. A few showers or
thunderstorms may occur near the front. High pressure ridging
into the forecast area from the north will bring lower
temperatures during the rest of the workweek.

&&

Near term /through tonight/...
little change in the air mass will occur today. It will be hot
again and the consistent temperature guidance supports highs
mainly in the middle 90s. Mid-level shortwave ridging should
help suppress thunderstorms. The NAM, GFS, and European model (ecmwf) MOS have
pops less than 20 percent. The high-resolution models suggest
isolated thunderstorm coverage at most.

The models show a backdoor cold front tonight. Convergence
along the front is depicted weak. There is also forecast to be a
mid-level shortwave trough late. Based on the noctural timing
and weak front we leaned toward the lower pop guidance.
Instability should be weak and expect mainly showers instead of
thunderstorms. The temperature guidance was close.

&&

Short term /Wednesday through Thursday/...
temperatures will lower 10 to 15 degrees behind the front for
Wednesday through Thursday with highs in the upper 70s to lower
80s and lows in the mid 50s to lower 60s.

&&

Long term /Thursday night through Monday/...
high pressure aloft remains over the southeast U.S. Through this
week with a gradual warming trend. An upper trough is forecast to
flatten the upper ridge. The impacts of an associated cold front may
be just beyond the forecast period.

&&

Aviation /06z Tuesday through Saturday/...
expect mainly VFR conditions through the 24-hour taf period.

Ridging will likely continue to promote dry conditions at the
terminals through today. A dry near-surface layer should help
prevent fog during the early morning hours. The NAM and GFS MOS
plus most sref members maintained VFR conditions.

Mid-level shortwave ridging should help suppress thunderstorms
today. The NAM, GFS, and European model (ecmwf) MOS have pops less than 20
percent. The high-resolution models suggest isolated
thunderstorm coverage at most. The chance was too low to include
in the terminal forecast at this time.

The models show a backdoor front tonight. Convergence along the
front is depicted weak. There is also forecast to be a mid-level
shortwave trough late. Based on the noctural timing and weak
front we leaned toward the lower pop guidance. Instability
should be weak and expect mainly showers instead of
thunderstorms. Again, the shower and thunderstorm chance was too
low to include in the terminal forecasts at this time. Most of
the guidance indicated a VFR ceiling associated with the front.

Followed the NAM and GFS MOS for the wind forecast will mainly
northeast wind less than 10 knots.

Extended aviation outlook...an MVFR ceiling may occur in the
northeast flow just behind the cold front early Wednesday.
Otherwise, no significant impacts are expected during the
outlook period.

&&

Cae watches/warnings/advisories...
Georgia...none.
SC...none.

&&

$$
Synopsis...99

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