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Area forecast discussion 
National Weather Service Charleston WV
1217 am EST Sat Feb 28 2015

Synopsis...
high pressure into Saturday night. Warm front/cold front combo Sunday
into Sunday night. Drier Monday into Monday night. Another
warm/cold front combo Tuesday into Wednesday.

&&

Near term /through today/...
not a whole lot to talk about in the near term. Clear skies will
usher in a frigid night...though high clouds will sweep in
periodically helping keep US a little warmer.

Saturday should be a welcome warm up as high temperatures approach
normal before the next system approaches.

&&

Short term /tonight through Monday/...
high pressure exits northeast
Saturday night allowing h850 to shift from the southwest to start
bringing warmer and moister air mass over the area for the
weekend. Models lift the freezing line north of the area by 00z
Monday. Surface temperatures will moderate some compared with previous
days.

Models continue to bring a weak short wave in a zonal flow at h500
crossing east on Saturday evening. However...models have this
feature further north across PA. Nevertheless...expect some
interaction with a lifting warm front feature from the south Sunday
morning...bringing the onset of precipitation as snow...but quickly changing
to rain as aforementioned warm temperatures move in. Have likely pop
as not trusting a warm front lifting from the south.
Meanwhile...likely to categorical probability of precipitation spread across the portions of
southeast Ohio...east with a cold front changing precipitation to snow across
the north late Sunday and Sunday night. The rest of The Lowlands
will see liquid precipitation Sunday...transitioning into snow or mixed precipitation
Sunday night as the precipitation moves east over the mountains before
ending early Monday.

BUFKIT sounding suggest 1 to 3 inches of snow will be possible over
portions of northern southeast Ohio...Perry and Morgan counties with
the cold front. Continued wording in severe weather potential statement for potential advisories
due to snow on Sunday. Snow also possible over the northeast
mountains Sunday night. Figured light accumulations of around 1.5
inches over the mountains.

Have the warmer temperatures on Sunday...generally in the middle to
upper 40s...and middle to low 30s Sunday night. Monday remains
relatively warm but with plenty of clouds covering the skies.

Went with the bias corrected consensus MOS blended with bias
corrected NAM temperatures through the period.

&&

Long term /Monday night through Friday/...
models starting to come into better agreement with each other in
terms of overall pattern...although timing issues remain. Brief
break in the precipitation expected for the first part of
Tuesday...as high pressure holds on a little longer. However...this
will change as a warm frontal boundary lifts north across the
region. Depending on surface temperatures...could see a brief period
of freezing rain or even sleet at the onset Tuesday...before enough
warm air is able to surge north to scour out colder surface
temperatures.

Still looking like good tap of Gulf moisture surging into the region
Tuesday into Wednesday with strong southwesterly winds
developing...with precipitable water values expected to rise around 1.2 to 1.3
inches...or about 3 Standard deviations above normal for this time
of year. This...along with the strong dynamics...will result in
heavy rain across the area...with a general 1 to 2 inches of rain
expected...with the higher amounts at this point expected across WV
lowlands and southeast Ohio. The heavy rain...combined with any snow
melt that is able to occur due to warming temperatures...could
create flooding issues. There is a general 2 to 4 inches of water in
the snow pack across the mountains. Of course there is still
uncertainty as to how much snowmelt will occur and how rapid it will
be. Will need to monitor area creeks and streams initially with this
system...and possibly rivers as time progresses.

The good news is...models have trended towards a more southerly
track with the low that will develop and push across the southeast
U.S. Middle week. This should hopefully keep the bulk of moisture with
that low to our south.

Cold front will push through the County Warning Area Wednesday or early
Thursday...with a general drying trend taking hold as high pressure
builds in from the west. Any precipitation will change over to light
snowfall behind the front. Will continue to mention flooding
potential in the severe weather potential statement for the time period.

&&

Aviation /06z Saturday through Wednesday/...
VFR conditions can be expected today. Some MVFR restrictions in snow
and clouds are possible late this evening in southeast Ohio.

Forecast confidence and alternate scenarios through 06z Sunday...

Forecast confidence: high.

Alternate scenarios: none.

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.

Date Sat 02/28/15
UTC 1hrly 06 07 08 09 10 11 12 13 14 15 16 17
EST 1hrly 01 02 03 04 05 06 07 08 09 10 11 12
crw consistency h h h h h h h h h h h h
heights 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 06z Sunday...
IFR possible in rain or mixed rain/snow late Saturday night into
early Monday. IFR possible again in rain showers Tuesday into
Wednesday.

&&

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

&&

$$
Synopsis...arj/sl/jw
near term...jw
short term...arj
long term...sl
aviation...rpy

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