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Area forecast discussion 
National Weather Service Jackson Kentucky
342 am EDT sun Aug 31 2014

Short term...(today through monday)
issued at 335 am EDT sun Aug 31 2014

Early this morning...the region remained in a very moist airmass
with precipitable water of 2 inches or more extending into the Ohio Valley region
between a ridge of high pressure centered off the southeast US coast
and a shortwave trough extending south from the Great Lakes into the
MS valley region. A lull in the shower and thunderstorm activity is
working north and northeast across the County Warning Area at this time as the first wave is
beginning to depart. However...the next wave is working into the middle
MS and lower Ohio Valley region as the deep moisture plume remains.

Over the next couple of days...the initial wave will depart to the
north and northeast...but the next most evident at the 850 mb and 700
mb level is expected to track east northeast across the Ohio Valley
region today. This system should once again interact with the deep
moisture plume in place across the region and lead to renewed
convective activity to our west gradually transitioning into eastern Kentucky
later tonight and into the day on Sunday. This system will depart to
the north and east tonight. The southeastern ridge is expected to
flatten by tonight and into Monday. The next trough will have moved
into the upper MS valley region and plains from The Rockies by late
tonight...with this trough working into the Great Lakes and
approaching the lower Ohio Valley region late in the period. The
associated surface cold front is also expected to approach the lower Ohio
Valley region late in the period...but will have more of an effect on
the long term portion of the forecast.

Recent hrrr runs bring the strongest activity across the region
during the afternoon into the early evening on Sunday. This activity
should be efficient rain producers and where any training occurs
locally heavy rain and flash flooding will be possible. A Flash Flood
Watch is already in place across western and northwestern parts of
the County Warning Area at this time and we plan to keep it in place with no changes. Later
shifts may want to consider extending it further south and east...but
rainfall over the past 24 hours has been generally lighter there
compared to the southwestern part of the County Warning Area where radar estimates
and rain gages indicate that upwards of 2 inches or more has fallen
across parts of Wayne County and from McCreary County northeast into
Laurel County. Temperatures today should be suppressed below
saturdays levels by the anticipated cloud cover and precipitation.
Locally heavy rain will be mentioned in the severe weather potential statement outside of locations
currently in the Flash Flood Watch.

With the wave departing tonight...chances for convection will also
diminish. Min temperatures will remain on the mild side. At least
patchy valley fog should develop...where any partial clearing
occurs. On Monday...the region will more or less be in between
systems with continued southerly flow and not much in the way of
forcing. Maximum temperatures will again be a few degrees above normal
and could approach 90 in some locations. The daytime heating of the
warm and rather moist airmass in place by the afternoon should lead
to some diurnally driven convection for Monday. At this time...only
isolated probability of precipitation were used.

Long term...(monday night through saturday)
issued at 252 am EDT sun Aug 31 2014

Summer-like weather will persist this week with plenty of warm and
humid conditions on tap. A strong ridge will continue to reside over
the southeast through the week. Best chance of rain will come on
Tuesday as a surface trough drops into eastern Kentucky before
stalling. Some weak forcing will yield scattered to numerous showers
and storms through the afternoon and evening hours. Decent shear
profiles...combined with modest instability could yield the
possibility of a few strong to severe storms on Tuesday with the
main threat being damaging winds. Otherwise...the front will stall
over the area Tuesday night...and virtually wash out. The
threat for afternoon/evening showers will continue through weeks end
given the daytime instability each afternoon/evening. Temperatures
will remain near or slight above normal through the week with all
the cooler air bottled up well to our north.


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 215 am EDT sun Aug 31 2014

MVFR or IFR visible and or ceilings are anticipated as the band of convection
works across the eastern and northeastern part of the County Warning Area over the
next 2 to 3 hours. VFR has developed behind this band of precipitation
and as the lull in the activity works north across east Kentucky...VFR ceilings
are anticipated until at least the 12z to 15z range. The press
gradient appears great enough to keep the taf sites mixy overnight...but
some MVFR or Lower Valley fog may still develop between 6z and 12z at
non taf sites. More showers and some thunder may develop again during
the 15z to 18z period...with this activity diminishing by the last 6
hours of the period.


Jkl watches/warnings/advisories...
Flash Flood Watch through this afternoon for kyz044-050>052-



long term...kas

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