Area Forecast Discussion
Issued by NWS Charleston, WV-- Highlight Changed Discussion --
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FXUS61 KRLX 180224
Area Forecast Discussion
National Weather Service Charleston WV
1024 PM EDT Mon Oct 17 2016
Southerly winds will keep the unseasonably warm weather in place through
the first half of the week. A frontal system then brings unsettled
and cooler weather by mid week, lasting through late week.
.NEAR TERM /THROUGH TUESDAY/...
-- Changed Discussion --1020 PM Update...With clear skies and calm winds in the sheltered
mountain valleys of Pocahontas and Randolph Counties, efficient
radiational cooling has dropped temperatures faster than
previously expected. Have went ahead an lowered temperatures
overnight a few degree across sheltered valley locations in the
735 PM Update...Just very minor changes made to the forecast. Put
patchy fog in the Tygart Valley as boundary level flow is going
will be weaker there overnight and at 15 to 20 knots they should
As of 110 PM Monday...
Latest surface map shows an area of high pressure centered over
the Southeast States. As a result, southerly winds prevailed across
the forecast area. The combination of southerly winds and abundant
sunshine in many areas has resulted in afternoon temperatures
warming into the 70s in most lowland locations.
The area of high pressure is expected to move away from the area
which will allow a cold front to approach from the northwest. The
pressure gradient should act to keep winds up tonight which, in
turn, should result in above normal overnight temperatures.
In advance of the cold front, clouds should begin to spread across
the area on Tuesday. However, models suggest that the clouds may
be slow to move east. Have gone with this thinking and as a
result, afternoon reading could approach record values. A few
locations may even break record highs.
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.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
As of 305 PM Monday...
Upper ridge over the eastern portion of the nation only slowly
erodes as an amplifying upper trough digs into the center portion
of the nation. This will allow a weakening frontal system to edge
south and east into portions of southeast Ohio later Tuesday night
and early Wednesday, before stalling as the upper flow ahead of
the upper trough becomes southwesterly. Models agree on the mass
fields, but some are rather aggressive with developing QPF along
the weakening front. With heights aloft still remaining rather
high, and an upper disturbance associated with any QPF Tuesday
night and early Wednesday lifting up across Indiana and Ohio, we will
be conservative this period with the coverage and QPF amounts.
Will confine low chance pops across portions of southeast Ohio,
and slight chance pops into northwestern WV.
During Wednesday, models have the front retreating north as the
upper trough and associated cold front approach from the west.
This will leave much of Wednesday on the dry side, with pops again
increasing over portions of southeast Ohio and northwestern WV
Wednesday night as the main system approaches.
Look for one last day on Wednesday of temperatures well into the
80s except portions of southeast Ohio where clouds and a few
showers may lower highs back into the 70s. Wednesday night will
continue well above normal.
.LONG TERM /THURSDAY THROUGH MONDAY/...
As of 305 PM Monday...
Models have the upper trough and associated cold front
progressive, but not that fast until the upper trough becomes
negatively tilted Thursday night and accelerates the front
eastward. Thus, we look for showers, and a few storms south,
overspreading the area from west to east Thursday and Thursday
night, then mostly ending from west to east during Friday as the
system sweeps through. Behind the front, good cold advection and
upslope will retain some post frontal showers, especially in the
mountians into Friday night and Saturday morning. Much cooler
temperatures will follow the front Thursday night and Friday, with
highs Friday actually a bit below normal in the lower 60s. Enough
cool air may bring a few snow flakes to the highest northern
mountain elevations Friday night with no accumulation.
Thereafter, look for high pressure and a slow warming trend.
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
As of 735 PM Monday...
Just minor changes made with the issuance of the 00Z TAFs. The southerly
winds, just above the surface still appear strong enough tonight
to inhibit fog development everywhere, but EKN. Low level flow
over EKN is forecast to be anywhere between 15 - 20 knots
overnight, and usually at that speed they should decouple. I have
brought IFR fog into EKN and keep it there through the early
morning hours, however it should mix out fairly quickly in the
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z WEDNESDAY...
FORECAST CONFIDENCE: High everywhere but EKN where confidence is
ALTERNATE SCENARIOS: If boundary layer flow is a bit stronger than
forecast then EKN will not see IFR fog.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
EDT 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
CRW CONSISTENCY M L M H H H H H H H M M
HTS CONSISTENCY H H H H H H H H H H M M
BKW CONSISTENCY H H H H H H H H H H M M
EKN CONSISTENCY L L L L H H H H H H M M
PKB CONSISTENCY L L M M H H H H H H M M
CKB CONSISTENCY M M M M H H H H H H M M
AFTER 00Z WEDNESDAY...
Typical early morning valley fog possible next week.