Scientific Forecaster Discussion
fxus61 krlx 270216
Area forecast discussion
National Weather Service Charleston WV
915 PM EST sun Feb 26 2017
high pressure through tonight. Warmer with upper level
disturbances and rain showers next week.
Near term /until 6 am Monday morning/...
as of 915 PM Sunday...
Only minor tweaks to the forecast this evening.
As of 521 PM Sunday...
Slowed sky cover arrival a bit this evening. With winds in the
eastern valleys expected to go calm, should have several good hours
of radiative cooling. Will Lower Valley temperatures in the east
closer to MOS guidance values.
As of 950 am Sunday...
Surface high pressure remains in control of the weather conditions
through tonight. Then, a series of h500 short waves noticeable
in vorticity field, will pass across the area early Monday.
These features could bring a chance for rain showers mainly
across southeast Ohio and portions of northern WV. Temperatures
will be around normal tonight, with values ranging from the middle
30s lowlands, into the middle 20s higher elevations. Highs on
Monday will be above normal per plenty of sunshine and southerly
Used the blend of models guidance through the period.
Short term /6 am Monday morning through Wednesday night/...
as of 245 PM Sunday...
Warm air advection continues with a passing warm front on
Tuesday. This front will bring light rain showers and possibly
an isolated thunderstorm. Moisture will increase under deep
southwesterly flow through Wednesday with ensembles showing
anomalous precipitable waters of 2 to 3 Standard deviations above normal by
12z Wednesday morning. An amplifying upper trough sweeps
southeastward into the Ohio Valley Wednesday afternoon, driving
a strong cold front through our area. Operational and ensemble
guidance is in generally good agreement on this feature and
confidence for widespread heavy showers and thunderstorms is
Whether or not any storms will be severe Wednesday afternoon is
still uncertain. However, this pattern is very similar to the
front that went through this past Saturday, but current timing
has this front reaching the Ohio Valley in the afternoon hours
instead of overnight. Dew points are prognosticated to be in the upper
50s and even if there is extensive cloud cover, cape values
still look to be in the 500 to 750 j/kg range. Very strong
southwesterly wind field yields an impressive shear profile with
current GFS indicating 60 to 70 kts of 0-6km bulk shear. The
modest instability could be a limiting factor to severe
potential, but we will likely have to monitor over the next
couple days as the forecast details unfold.
The cold front should clear the area late Wednesday night. With
the upslope northwest flow behind the front precipitation may change
over to snow showers in the mountains earlier at higher
elevations than currently forecasts, but little accumulation is
Long term /Thursday through Sunday/...
as of 300 PM Sunday...
Forecast guidance continues to indicate a weak clipper system
Thursday night into Friday. Cold air will be in place and most
of the area has the possibility to see snow showers, but
confidence is very low whether there will be any accumulations,
with northern areas and the mountains being most likely to see
accumulations. High pressure builds back over the region for the
Aviation /02z Monday through Friday/...
as of 557 PM Sunday...
VFR conditions can be expected this evening. A disturbance moving
across the area late tonight and Monday may provide some light rain.
Even so, conditions will remain VFR at most locations, although some
MVFR conditions can not be ruled out in central Ohio.
Forecast confidence and alternate scenarios through 00z Tuesday...
Forecast confidence: high.
Alternate scenarios: timing of showers are not included in the tafs
due to chances of precipitation being below 50 percent.
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 00 01 02 03 04 05 06 07 08 09 10 11
EST 1hrly 19 20 21 22 23 00 01 02 03 04 05 06
crw consistency h h h h h h h h h h h M
heights consistency h h h h h h h h h h h M
bkw consistency h h h h h h h h h h h M
ekn consistency h h h h h h h h h h h M
pkb consistency h h h h h h h h h h h M
ckb consistency h h h h h h h h h h h M
After 00z Tuesday...
no widespread IFR conditions are expected at this time.