Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 200705

305 AM EDT Mon Oct 20 2014

.SHORT TERM (Now through Tuesday)...
Issued at 305 AM EDT Mon Oct 20 2014

Things are quiet across the CWA at this hour, with only some mid and
upper level sky cover in place, and temperatures running in the low
and mid 40s. Will watch chances for isolated to scattered rain
showers increase over the next few hours ahead of a PV anomaly
diving in from the upper Midwest. Light rain showers have already
begun to organize from NW Indiana through southern Missouri ahead of
this feature, and expect a cluster of these showers to mainly focus
over southern Indiana and northern Kentucky later this morning. Less
impressed with measurable rain chances across south central KY where
there will be less moisture and more displaced from the best
forcing. Can`t rule out an isolated sprinkle, but think measurable
rain will be hard to come by. Will see temperatures warm to the mid
and upper 60s today on a steady SW wind, despite the lack of strong
solar insolation.

Will keep an chances for an isolated shower in across the far NE
into the late evening hours where deep moisture will be most
impressive. Things should dry out after Midnight. Will see milder
lows tonight under cloud cover and a somewhat mixy near-surface

Will have one more shot at isolated light rain showers across our NE
on Tuesday morning as another wave dives into the mean trough over
the eastern CONUS, and combines with the lingering low level
moisture. Most spots will stay dry this day with a fairly sizable
temperature gradient across the CWA. Look for upper 50s NE to mid to
upper 60s SW.

.LONG TERM (Tuesday Night through Sunday)...
Issued at 300 AM EDT Mon Oct 20 2014

An extended period of tranquil fall weather is on the way, with no
precip chances in the forecast through Sunday. The middle of the
week will feature shortwave ridging aloft, but Canadian surface high
pressure will be drawn southward behind a slowly departing East
Coast low. This will keep out temps below normal for most of the
work week. Coldest mornings will be Thursday with the surface ridge
axis directly over the Ohio Valley, and Friday as favorable
radiational cooling conditions persist. More sheltered/rural
locations could see lows in the 30s, and frost can`t be ruled out

By the weekend, the next upper shortwave trof will weaken as it
heads into the Great Lakes, and with precipitable water values
barely touching climo, the only sensible weather impact will likely
be an increase in cloud cover. Temps will recover to near or above
climo as upper ridge starts to build from the SW, but that could be
limited by N-NE low-level flow depending on how strongly the surface
high is reinforced by the weakening upper impulse. Current forecast
is more in line with the raw model consensus, but if the upper
ridging wins out extended GFS MOS highs in the 70s could be the way
to go.


.AVIATION (06Z TAF Update)...
Updated at 105 AM EDT Mon Oct 20 2014

VFR conditions will prevail at the TAF sites for much of the
overnight, however will focus on an incoming disturbance toward the
later morning hours. Ceilings are currently broken above 10 K feet,
however expect ceilings to gradually lower toward dawn, but remain
VFR. Some light rain showers will be possible at SDF/LEX ahead of a
mid level disturbance with the best timing between 7 and 9 AM EDT at
SDF, and between 9 and 11 AM EDT at LEX. Think these showers will be
light enough that visibilities should stay above 6 SM, however
cannot rule out a brief drop into MVFR.

Otherwise, surface winds will be light out of the south, gradually
increasing in strength and veering to SW through the day. Low and
mid level clouds will hang around this evening, however expect just
above the MVFR/VFR threshold at this time.




Short Term........BJS
Long Term.........RAS
Aviation..........BJS is the U.S. government's official web portal to all federal, state and local government web resources and services.