Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 261644
Area Forecast Discussion
National Weather Service Louisville KY
1144 AM EST THU NOV 26 2015
...Updated Aviation Discussion...
.SHORT TERM (Now through Friday)...
Issued at 256 AM EST Thu Nov 26 2015
Dry conditions are still expected today and most of tonight as we
await the approach of a cold front coming in from the west. Clouds
will temper afternoon highs, but in our position ahead of the cold
front with southerly breezes we should still be able to get well
into the 60s. Will go on the warm side of guidance which has been
too cool the past few days.
A long cold front will slowly edge toward us from the northwest on
Friday, stretching from New England to the Ohio Valley to the Rio
Grande by evening. Shower chances will steadily increase, with the
best chance of rain northwest of a Bowling Green-Lexington line.
High temperatures will range from around 60 northwest of Louisville
to possibly near 70 along the Tennessee border east of Bowling Green.
.LONG TERM (Friday Night through Wednesday)...
Issued at 317 AM EST Thu Nov 26 2015
Over the weekend the front will weaken and become quite subtle as it
lingers in the area. Nevertheless it will serve as a corridor for
deep RH streaming in from the southwest. A plume of 1 to 1.5" PWAT
air (*well* above normal for late November) coming up from the
western Gulf of Mexico, enhanced by mid and upper moisture from the
remnants of Pacific Hurricane Sandra ahead of a western CONUS upper
trof, will lead to widespread rain over the weekend.
K Index values remain low and forcing will be weak. Low level theta-
e ridging will be present but weak and instability will be virtually
nil, so heavy downpours are not expected. However, light to moderate
rains will be common within a broad area of isentropic lift and will
add up over time.
On Monday the upper low over the Intermountain West should finally
start to kick off to the east, cross the Great Lakes Tuesday, and
head for New England Wednesday. Ahead of the upper low, a surface
low should develop over the lower Mississippi Valley Monday and head
north to the western Great Lakes Tuesday. It will pull a warm front
northward through the TN and OH valleys Monday, followed by its cold
front late Monday night/Tuesday morning. As a result, showers will
remain in the forecast into early next week. Once again instability
looks very weak so will leave thunder out of the forecast.
1.5 to 3 inches of rain is still in the forecast for totals during
the Friday-Tuesday time frame.
Will go dry for Tuesday night and Wednesday as the storm system
pulls off to the northeast.
No cold weather is in the forecast for the next several days with
lows generally in the 40s and 50s. We may get down into the 30s
Wednesday morning if the Mon/Tue storm system can move off enough to
the east to allow high pressure to nose in from the west. Still, not
too bad for December.
.AVIATION (18Z TAF Update)...
Updated at 1143 AM EST Thu Nov 26 2015
Plan on VFR conditions through the period as region will remain in
south/southwest flow ahead of an approaching cold front. Gusty winds
this afternoon will slacken off toward sunset, but remain in the 5-7
kt range through the overnight. Expect scattered/broken mid clouds
at times, becoming thicker toward the end of the period.
Precipitation is expected to hold off until after 18z at LEX/BWG. At
SDF, rain showers will be approaching from the northwest, likely not
reaching the terminal until 21z.