Area Forecast Discussion
Issued by NWS Greer, SC
Issued by NWS Greer, SC
081
FXUS62 KGSP 171120
AFDGSP
Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
620 AM EST Mon Nov 17 2025
.SYNOPSIS...
High pressure will bring very dry air and near-normal temperatures
early this week. Conditions will become very warm again during
the latter half of the week ahead of the next cold front, which
may bring rain chances next weekend.
&&
.NEAR TERM /THROUGH TONIGHT/...
As of 617 AM EST Monday: Deep layer northwesterly flow sticks around
through the daytime period. Surface high gradually building in from
the northwest will allow for a very dry airmass to set up shop
across the CWFA. Boundary layers have struggled to fully decouple
overnight with lingering gap winds, which will keep occasional low-
end gusts. CAA from the departing cold front from yesterday and good
radiational cooling has allowed for some locations to drop well into
the 30s, while locations still experiencing the gap wind has
remained well into the 40s. Still gusty over the higher terrain, but
temperatures are below freezing this morning.
Center of the surface high will be over the OH/TN Valleys during the
daytime period as the very dry air mass remains in place. Expect RH
values to dip below 25%, even into the teens for a period of time
by the afternoon hours for most locations. Fire weather concerns
will be elevated despite lower winds as the pressure gradient mostly
relaxes. Will likely need another Increased Fire Danger Statement
for portions of the CWFA. Afternoon highs will be a few ticks above
normal and closer to normal values across the higher terrain. Good
radiational cooling conditions are expected overnight Monday as the
surface high fully situates over the area with mostly clear skies
and light winds. As a result, overnight lows will be up to 5 degrees
below normal.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
As of 1215 pm Monday: A consensus of the latest short term guidance
has trended stronger and farther south with a compact upper
low that will move from the Corn Belt through the Mid-Atlantic
during the first half of the period. Resultant surface wave
development/baroclinic zone activation should result in precip
development across the region...primarily across the central
Appalachians and Mid-Atlantic. Nevertheless, the farther south
trend in guidance warrants an increase in PoPs Tue night across
the mountains (50-60%) and along the I-40 corridor east of
the escarpment (20-30%). Any rainfall should it occur be very
light...around a tenth of an inch or less. Otherwise, the pattern
will support establishment of a broad warm sector across the
Southeast, while heights will be on the rise as an upper ridge
builds to our west. Temps will soar on Wed as a result, with maxes
forecast to be almost 15 degrees above climo. Otherwise, low level
moisture/precipitable water values will steadily increase through
the period as S/SW return flow becomes established. One more
day with critical or near-critical RH is expected Tue afternoon,
but RH should increase significantly during mid-week.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 1235 AM Monday: A complex, quite amplified split flow upper
air pattern is forecast to evolve during the extended period,
with perhaps a bit of a Rex block becoming established across the
West. Timing of speed maxima ejecting through a long wave trough
across the southwest quadrant of the country will potentially have
major implications on the sensible weather across our area late
in the week, but this is very uncertain given the complexity of
the pattern...confirmed by rather disparate solutions regarding
the short wave details among the various deterministic global
models. Nevertheless, the potential for showers will steadily
increase from the west through the period, with general 40-60%
chances advertised across the mountains by Saturday...and mainly
token chances elsewhere. Otherwise, heights over the Southeast
will be anomalously high through the period, resulting in forecast
temps 10-15 degrees above normal through the period.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
At KCLT and elsewhere: VFR conditions expected through the forecast
period. Winds remain north-northwesterly through the morning hours.
Winds should turn west to southwesterly by the afternoon before
going light and variable after sunset, remaining that way through
the rest of the night. KAVL maintains a northwesterly component with
low-end gusts through most of daytime period before gradually
diminishing after sunset. Mostly clear skies through the daytime
period with some coverage of cirrus moving into the area by the
evening and early parts of the overnight.
Outlook: A low pressure system may bring scattered showers and
associated restrictions on Tuesday, possibly lingering into
Wednesday. Dry high pressure returns briefly on Thursday, before
another cold front potentially brings showers and restrictions on
Friday and over the weekend.
&&
.FIRE WEATHER...
Winds will be lower for today, but RH values will dip below 25% for
most of the area as a very dry air mass remains in place. Increased
fire danger conditions are expected once again as Fire Danger
Statements will likely for portions of the CWFA for this afternoon
and evening.
Humidity and temperatures are expected to steadily increase tonight
through mid-week. One more afternoon of critical RH is likely
Tuesday, but minimums are expected to be more in the 20-25% range.
Although RH is expected to be well above critical levels for the
remainder of the week, very warm days are also expected, so some
degree of wildfire risk is likely to continue in light of low 10-
hour fuel moisture.
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...Increased Fire Danger from 11 AM EST this morning through this
evening for GAZ010-017-018-026-028-029.
NC...None.
SC...None.
&&
$$
SYNOPSIS...JDL
NEAR TERM...CAC
SHORT TERM...JDL
LONG TERM...JDL
AVIATION...CAC
FIRE WEATHER...CAC