Area Forecast Discussion
Issued by NWS Charleston, WV

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KRLX 281722
AFDRLX

Area Forecast Discussion
National Weather Service Charleston WV
122 PM EDT SAT MAY 28 2016

.SYNOPSIS...
Slow moving convection with heavy downpours again today. Moist
southeast flow will raise shower chance Sunday in the mountains.
Upper level ridge rebuilds next week.

&&

.NEAR TERM /THROUGH SUNDAY/...
Overall...no significant changes were necessary to the previous
forecast. As expected...sct showers and thunderstorms have started
to develop across Ohio...and am expecting sct showers and
thunderstorms to develop across southeast Ohio...NE KY...and
adjacent WV counties this afternoon...as upper disturbances moving
north out ahead of an approaching upper trough affect the area.
In addition...isold convection has developed across the northern
mountains just outside the CWA due to differential heating...and
will maintain a slight chance across northern mountain zones this
afternoon. As with yesterday...overall flow is light...and storms
will be slow to move and contain heavy downpours.

Bulk of convection will briefly die down
tonight...however...things will ramp up again towards morning...as
a combination of moisture from a tropical depression...which will
move inland towards South Carolina...and upper trough moves in
from the west. Models seem to be backing off a bit on how much
moisture and energy will actually make it into our CWA from the
tropical depression...and elected to back off the pops a bit
tomorrow across the east as a result. Still...looking at overall higher
pops across the east...with lower pops across the central and
western counties as upper trough pushes east into region.

With the expected cloud cover and shower activity on
Sunday...temperatures will be several degrees cooler than in
recent days...particularly across the east.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
Afternoon heating, precipitable water around 1.25 and some bouyancy
will keep low chance pops sunday night. Although low level moisture
decreases some, there will be enough instability and moisture to
keep isolated showers or storms on Monday. Meanwhile, a cold front
approaches from the west bringing better chance for showers or
storms.

The GFS and ECMWF show decreasing QPF Sunday night and early Monday.
While the GFS show afternoon convection, the ECMWF keeps light
showers for the whole day Monday. Went with a compromise between
these two models coding chance PoPs.

Models are in agreement bringing dry conditions Tuesday and
Wednesday with mostly clear skies.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Another cold front approaches from the west Thursday can be enhanced
by afternoon heating and associated convection. The area will remain
under the warm sector of the next low/cold front system Thursday and
Friday. Increase PoPs higher than 50 percent and likely PoPs over
elevations of 3000 feet and higher.

A tropical storm could become sub tropical as it exit the mid
Atlantic states northeast over the off shore waters. The general
track northwestward to the South Carolina coast this weekend...and
then just sits there through early next week...as the supporting
upper trough is sheared north and northeast thru the Mid Atlantic
states on Sunday. This shearing out of the upper trough on Sunday is
caused by the current Plains upper low opening up and moving east
across the Great Lakes. This second system is strong enough to drive
a weak front across the area Sunday night and Monday morning.

Went with a combination of the super blend and the all blend
guidance for temperatures through the period.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
ISOLD to SCT showers and thunderstorms...mainly across southeast
Ohio...WV lowlands...and northeast Kentucky through 02Z.
Otherwise...increasing bkn-ovc vfr sky cover overnight...as
moisture from a low along the Carolina coast advects into the
region. Thinking this should to keep much fog development tonight
at bay.

After 12Z...sct showers and thunderstorms will develop
again...with heavy downpours...and brief mvfr/ifr conditions in
vcnty of storms. Elsewhere...VFR with light surface winds.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SUNDAY...

FORECAST CONFIDENCE: High.

ALTERNATE SCENARIOS: Extent and coverage of convection this
afternoon remains in question...especially regarding any location
that may be affected.

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       15   16   17   18   19   20   21   22   23   00   01   02
EDT 1HRLY       11   12   13   14   15   16   17   18   19   20   21   22
CRW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
EKN CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
CKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H

AFTER 18Z SUNDAY...
No widespread IFR conditions expected.

&&

.HYDROLOGY...
The river gauge...and forecast point...at the South Side Bridge
in downtown Charleston has not be reading correctly. The NWS
hydrologist is working to correct this problem.

&&

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

&&

$$
SYNOPSIS...ARJ/SL
NEAR TERM...SL
SHORT TERM...ARJ
LONG TERM...ARJ
AVIATION...SL

HYDROLOGY...ktb



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.