Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 030443
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
1243 AM EDT Sun May 3 2015
...Updated Aviation Discussion...
Updated 928 PM EDT Sat May 2 2015
Winds are light this evening with a few to scattered clouds around
the area. Taking a look at the model guidance this evening, still
think there is the potential for some patchy fog to form
tomorrow morning as more moist air begins to advect into the region.
However, am not sure how widespread it will be, so the wording was
limited to "patchy" in the forecast. Otherwise, just some minor
adjustments were made to the temp/dewpoint grids this evening.
.SHORT TERM (Now through Sunday Night)...
Issued at 310 PM EDT Sat May 2 2015
Nice warmup to continue as high pressure over the region will shift
east of it overnight and settle over the Carolina coast by Sunday
night. Southerly winds will bring that warmer air, with highs
getting to around 80 in our warm spots and lows generally in the
50s. The only concern for tonight would be chance for fog. With the
high to our east, we will see a little more moisture in the region.
We did see a few patches of fog this morning and with a little more
moisture we could see better coverage by daybreak Sunday. Have put
in patchy to areas of fog for this reason.
.LONG TERM (Monday through Saturday)...
Issued at 325 PM EDT Sat May 2 2015
The long term period continues to look generally quiet throughout
the period. The long term global guidance continues to be in good
agreement with a deep western US trough developing with ridging
developing just east of the Mid-MS valley. The deterministic runs
along with quite a few of the ensembles continue to show the
development of a tropical system off the US SE coast by midweek.
Should this occur, it appears that a Rex block will be in place
across the eastern US which would generally lock the upper level
pattern in place. In this particular case, much of the Ohio Valley
would remain in a broad southwesterly flow pattern throughout the
The previous forecast had this well in hand and only some minor
adjustments were needed. In terms of sensible weather, a stalled
out frontal boundary will likely remain to the north of the region
early in the week and eventually wash out as stronger ridging
develops in response to the deepening western US trough and the
possible tropical development off the SE US coast. This will lead
to a continued warming and moistening of the column throughout the
week. By Thu/Fri the pattern may start to break down slightly with
the ridge axis drifting to our east. Increasing afternoon
instability may lead to diurnally driven convection mainly in the
afternoon/evening hours. However, still will keep PoPs in the
isolated range closer to climatology. By the weekend, the pattern
should break down even more allowing the western trough to come
eastward bringing our next chance of precipitation the region.
As for temperatures, we expect to see above normal temperatures for
the period. Afternoon highs in the lower to middle 80s are likely
with overnight lows cooling into the upper 50s to the lower 60s.
.AVIATION (06Z TAF Update)...
Updated at 1235 AM EDT Sun May 3 2015
Plan on VFR conditions through the period as high pressure pushes
off to the southeast. High clouds will move over SDF/LEX/BWG early
this morning, then look for scattered cu with bases around 5 kft
this afternoon. Light/variable winds this morning are expected to be
southerly to southwesterly between 5 and 10 kft by afternoon and