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Area forecast discussion 
National Weather Service Charleston WV
1056 am EDT Tuesday Jul 26 2016

Synopsis...
a weak east to west frontal boundary continues across northern
portions of area. Next system late in the week.

&&

Near term /through tonight/...
1030 am update. Adjusted placement of Max pops to focus along
front in the north early this afternoon...then shift southward
later this afternoon into central and southern areas prior to
significant decrease with loss of heating this evening.

Previous discussion...a weak quasi stationary front remains just
northwest of the area as seen in the sfc obs maps. The hrrr and
rap models bring precipitation during the afternoon hours when the heat is
at its peak. Diurnal heating will combined with abundant moisture
to produce showers or storms during the afternoon hours. A tongue
of moisture, evident in precipitable water around 2 inches
continues in place. This can support isolated heavy downpours
through tonight.

Went with the National blend of models for temperatures through
the period.

&&

Short term /Wednesday through Friday/...
models in decent agreement with a weak wave combining with daytime
heating to pop some showers and thunderstorms on Wednesday. Have
generally south to north pop gradient, with the highest pops across
southern County Warning Area gradually decreasing to the north.

The models are having a bit more trouble agreeing on a more
significant surface low for Thursday into Friday. NAM and GFS show
this wave riding along a warm front and crossing County Warning Area Thursday into
Thursday night... with the GFS a touch faster than the NAM. The
European model (ecmwf) is farther northwest with the surface low, and 12 to 18 hours slower.
At any rate, with the warm front lifting through the region went
with likely pops Thursday. Precipitable water values look to be 2+
inches with this wave, so will have to keep a close eye on rainfall
amounts, especially if the warm front is slow moving or becomes
stationary.

&&

Long term /Friday night through Monday/...
used a blend of the ecens mean...naefs mean...and gefs mean.
Weighted a bit more toward the ecens mean than the others. This
would leave the area in the warm sector with plenty of moisture Saturday.
A cold front would then push into the area Sunday. Still
questionable if this front would push south of the area or not for
early next week.

&&

Aviation /15z Tuesday through Saturday/...
15z Tuesday thru 12z Wednesday...
scattered-broken 2000-3000 feet agl becoming VFR ceilings 4000-5000 feet
by 17z...with scattered showers and tstms developing mainly across the
north by early this afternoon along the front. Convection then
sags southward later this afternoon into central and southern
sections of the area before decreasing this evening with loss of
heating. Will handle scattered convection with thunderstorms in the vicinity in tafs.

After 02z...generally scattered-broken 6000-8000 feet above ground level with widely scattered
showers mainly in the south. After 05z generally MVFR fog
especially where rain has fallen.



Confidence and alternate scenarios...

Forecast confidence and alternate scenarios through 12z Wednesday...

Forecast confidence: medium.

Alternate scenarios: a shower or thunderstorm could directly affect
any taf site Tuesday afternoon. Timing of fog formation and
intensity may vary tonight depending on where it rains.

Experimental table of flight category objectively shows consistency
of weather forecast office 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 M h h h h h h h h h h h
heights consistency M h h h h h h h h h h h
bkw consistency M h h h h h h h h h h h
ekn consistency M h h h h h h h h h h h
pkb consistency M h h h h h h h h h h h
ckb consistency M h h h h h h h h h h h

After 12z Wednesday...
brief IFR conditions possible in thunderstorms every afternoon
and evening. Early morning IFR fog possible into mid week
depending, in part, on occurrence of showers or thunderstorms the
previous afternoon or night.

&&

Rlx watches/warnings/advisories...
WV...none.
Ohio...none.
Kentucky...none.
Virginia...none.

&&

$$
Synopsis...jmv/mz
near term...arj/jmv
short term...mz
long term...rpy
aviation...jmv

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