222
FXUS61 KRLX 141105
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
705 AM EDT Tue May 14 2024

.SYNOPSIS...
Precipitation returns today with showers lasting into Wednesday
due to a slow moving low pressure system. Mainly dry Thursday,
then unsettled to end the week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 703 AM Tuesday...

Made some substantial upward adjustments to PoPs this morning to
better reflect widespread showers from the southern coalfields
to the Metro Valley heading north associated with a shortwave
lifting north. Should see a lull in precipitation/tapering to
isolated showers as subsidence behind this feature spreads over
the region late morning into early afternoon.

As of 640 AM Tuesday...

Updated temperatures, dew points and precipitation forecast,
otherwise everything remains on track.

As of 200 AM Tuesday...

Starting to see some light showers traverse the area this
morning as a surface trough extends over the region. A slow-
moving low pressure system over MO/IL will gradually make its
way to us today, while in the meantime sending more of these
shower spawning perturbations over the region.

For now, kept chance PoPs until the afternoon when more light to
moderate showers will move through from SW to NE. The heaviest
of the rain looks to hold off until this tonight though, and
even then amounts will be less than half an inch. WPC has most
of the area, minus the northern lowlands, outlooked for a
marginal risk of excessive rainfall as this will be more of an
accumulative event over the next few days.

Short-range guidance has been sticking to its guns on precipitable
water values nearing 1.50" the past few days, but latest HRRR
and NAM guidance has backed off quite a bit, still above 1.00"
though, but no higher than 1.30". Some localized flooding may
occur within some moderate to heavy bands of showers, but not
currently concerned with anything impactful.

Models are split on how warm temperatures will get today,
depending on extent of cloud cover. Starting to see more trend
downward though which would impact convection. We are outlooked
for general thunderstorms today, and a few isolated
thunderstorms are likely if clearing does occur this afternoon.
Models are slowing the speed at which the low pressure
circulation moves across the Ohio River Valley and keep the
region out of the warm sector. That said, instability looks very
meager (less than 500 J/Kg) until the low arrives later in the
evening.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
As of 250 AM Tuesday...

Both the upper-level and surface lows will take their time
moving across the area on Wednesday, with widespread showers and
embedded thunderstorms expected. The base of the upper trough
will slide off to the east Wednesday night, and precip coverage
should diminish across the area as a result. A shortwave upper-
level ridge will move over the area on Thursday, but indications
are that it will be a `dirty` ridge, with some showers and a few
thunderstorms possible. This activity will be strongly diurnally
driven, and also with a significant terrain influence, but we
could still see some convection in the lower elevations. All
activity seems likely to drop off Thursday night.

If there are any ongoing hydro issues Wednesday morning, they
could be exacerbated by the further rainfall during the day
Wednesday, but overall the system seems more likely to just be a
healthy soaking rain. Temps will remain somewhat suppressed on
Wednesday with the widespread clouds and showers, and should
bounce back a bit on Thursday.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
As of 315 AM Tuesday...

The next disturbance approaches on Friday, with shower and
thunderstorm activity likely increasing in the afternoon and
overnight hours. There is a chance this could be another slow-
moving system, but models disagree greatly on just how slow.
That said, likely POPs over 50% are maintained through Saturday.
After that, models diverge on whether there will be a break or
if this system will linger over the region, and on how quickly
the next disturbance will arrive. So while the uncertainty leads
to maintaining chance POPs across the area on Sunday and Monday,
it`s not likely to have activity across the area that whole
time. There will be breaks, but pinning down the time of those
breaks just isn`t possible at this time.

There`s a good chance that Friday will be a bit warmer than
normal ahead of the encroaching front and precip, with lower
elevation highs mainly in the lower 80s. The forecast is a few
degrees lower on Saturday with the greater confidence in it
being rainy and cloudy that day. Sunday and Monday temperatures
will likely hinge a lot on the evolution of the precip and sky
cover forecast.

&&

.AVIATION /11Z TUESDAY THROUGH SATURDAY/...
As of 645 AM Tuesday...

Showers will continue to move through the area early this
morning before slacking off some early in the afternoon.
Expecting more widespread coverage later this afternoon into the
overnight hours. VFR or high-end MVFR expected through the
morning, with the lowest CIGs and VIS most likely across the
mountains. Expecting a reprieve early this afternoon with most
sites seeing VFR.

MVFR CIG/VIS restrictions expected in any moderate to heavy
showers. Allowed VCTS this evening between ~23Z and ~03Z for a
few sites as forcing from a more prominent shortwave could
allow for some isolated TS, but not confident in this
manifesting due to very weak instability. MVFR and IFR
restrictions arrive in earnest overnight tonight with scattered
showers filling in Wednesday.

Winds mostly light with a southerly component through the
period, though will likely be breezy at times across the
mountains and the Ohio River Valley this afternoon.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z WEDNESDAY...

FORECAST CONFIDENCE: Medium

ALTERNATE SCENARIOS: VIS/CIGs could be lower than forecast
within moderate to heavier showers.




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    M    M    M    M    H    H    H    H    H    H    H
HTS CONSISTENCY  M    M    M    M    L    M    H    H    H    H    H    H
BKW CONSISTENCY  M    M    M    H    H    H    H    H    H    H    H    H
EKN CONSISTENCY  H    H    L    H    H    H    H    H    H    H    H    H
PKB CONSISTENCY  H    H    H    H    M    H    H    H    H    H    H    H
CKB CONSISTENCY  H    H    H    H    L    H    H    H    H    H    H    H

AFTER 12Z WEDNESDAY...
Scattered IFR visibilities and ceilings are possible in heavier
rain showers Wednesday morning.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...None.
OH...None.
KY...None.
VA...None.

&&

$$

SYNOPSIS...FK/LTC
NEAR TERM...JP/LTC
SHORT TERM...FK
LONG TERM...FK
AVIATION...LTC