Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 211905
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
305 PM EDT Thu May 21 2015
.SHORT TERM (Now through Friday Night)...
Issued at 303 PM EDT Thu May 21 2015
Northwesterly flow will continue aloft through the short term
period. At the surface high pressure will begin to build in from the
west tonight and will slowly slide eastward over the lower Ohio
Valley. The stubborn cloud deck that has been hanging around across
the region today should begin to clear out this evening with mostly
clear skies expected by tomorrow morning. Winds will become light
and variable to calm as the high pressure builds in. Some fog looks
possible tonight, particularly across south central KY where more
rain fell yesterday and early this morning. In addition, dewpoints
have stayed a bit higher today across this area. Lows tonight will
be in the lower to mid 40s.
Friday and Friday night will be mostly clear to partly cloudy. With
better insolation, temperatures should be much warmer than today.
Highs will range from the lower to mid 70s. Lows tomorrow night will
be in the lower to mid 50s.
.LONG TERM (Saturday through Thursday)...
Issued at 300 PM EDT Thu May 21 2015
Saturday - Sunday...
Upper level ridging will build over the Midwest Sat/Sun. Sat we`ll
be on the dry side of the ridge with temps warming into the upper
70s and low 80s. Long range models continue to trend drier for
Sunday as the ridge axis will be slow to make progress eastward.
Even ensemble data is now showing a much stronger ridge for Sun.
Therefore will continue the drier trend for Sunday making areas east
of I-65 completely dry and lower POPs along and west of I-65 into
the 20-30% range. Sunday`s highs should be warmer than Sat with
highs making it into the lower 80s area wide. Overnight low temps
should hold in the mid to upper 50s.
Monday - Thursday...
For the beginning of next week, the upper ridge will move to our
east and we`ll enter an unsettled southwest flow with multiple hard
to time upper level disturbances. Therefore will carry 30-50% POPs
during the week for on and off periods of showers/storms. Although
no really strong troughs look to impact the area attm, enough low
and mid level flow looks to be present on the western side of the
ridge for some storm organization throughout the week. Timing of
rounds of storms will impact available instability and so it is
difficult to pinpoint any great windows for strong storms. Storms
with brief heavy rainfall and gusty winds will be possible though.
Temperatures will generally be in the low 80s for highs and mid to
upper 60s for lows Mon-Thu.
.AVIATION (18Z TAF Update)...
Updated at 1247 PM EDT Thu May 21 2015
MVFR ceilings continue to persist this afternoon, though bases are
slowly rising. Models indicate that the lower level moisture will
continue to erode this afternoon as drier air builds in from the
north. Think that SDF and LEX will become VFR by late this afternoon
with BWG rising to VFR by early evening. Overnight skies will be
partly cloudy to clear. Some light fog will be possible at LEX and
BWG early tomorrow morning as winds become light and variable to
calm. Partly cloud skies are expected Friday with winds out of the
west to northwest.