Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 272315
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
715 PM EDT Fri Mar 27 2015
...Updated Aviation Discussion...
.SHORT TERM (Now through Saturday Night)...
Issued at 315 PM EDT Fri Mar 27 2015
An upper trough continues to cause light snow showers/flurries and
light rain showers/sprinkles across the area late this afternoon.
Expect this light precip to continue through the evening hours and
then dissipate after sunset. Precip amounts still look to be next
to nothing with this very light precip.
The rest of the short term period is dry with high pressure
remaining in control at the sfc and an upper trough aloft providing
unseasonably cold temperatures for late Mar. The temp/cloud
forecast is a bit tricky for tonight. It`s tough to say how long
low clouds will stick around in the northerly flow/CAA regime.
Compromising with model data and NWS neighbors, gradually have
clouds taper from west to east through the night which will result
in low temps in the low to mid 20s. If clouds clear faster than
currently forecast, valley locations and typical cold spots could
bottom out in the upper teens.
Sat will be sunny but chilly. Northerly winds and the cold airmass
should limit highs to the low to mid 40s. Another cold night awaits
for Sat night with low temps again dipping into the lower 20s...a
few upper teens possible.
Since hard freezes will occur both tonight and Sat night, any
outdoor plants should be covered or protected.
Record Cold Maxes for Saturday:
Mar. 28 Forecast
SDF 41 (1916) 44
LEX 37 (1947) 40
BWG 39 (1899) 46
.LONG TERM (Sunday through Friday)...
Issued at 300 PM EDT Fri Mar 27 2015
The surface high pressure of Canadian origin responsible for
unseasonably cold temperatures Saturday will move east of the
Commonwealth by Sunday afternoon. This, and a vigorous low moving
north of Lake Superior late in the day, will bring a decent
southwesterly return flow Sunday afternoon, resulting in a distinct
warmup after a chilly morning. After lows in the mid 20s,
temperatures Sunday afternoon will rebound well into the 50s, albeit
with increasing afternoon cloudiness.
A cold front will move southeast of the Ohio River Sunday night with just
a chance of some light showers or sprinkles. This front is actually
of Pacific origin, meaning the air behind this boundary will almost
be warmer than the continental air ahead of it.
For the period Monday through Thursday, broad 500mb ridging and warm
temperatures centered over the northern Rockies will push east,
spreading much milder temperatures first towards the Mississippi
River, and then across the Lower Ohio Valley. Normal highs for the
first of April are in the lower to mid 60s. By Tuesday, we should
match these pretty easily, with highs rising from the lower to mid
60s on Monday to as high as 70 from Tuesday onwards. Any light
precipitation will end Monday morning with clearing skies.
Expect mostly clear skies and dry weather Monday afternoon through
Wednesday morning. Modified Gulf moisture will begin to return
mid-week, but extended guidance is not in agreement when. Think the
GFS is way overdone in breaking out showers within a warm air
advection regime on Wednesday. Feel that the ECMWF and Canadian are
more on target in holding off a chance of showers until Wednesday
night or Thursday.
A cold frontal passage Thursday evening will bring a good chance of
showers and even some thunder. Distinctly cooler temperatures on tap
for Friday with highs in the 50s.
.AVIATION (00Z TAF Update)...
Issued at 715 PM EDT Fri Mar 27 2015
Surface High pressure ridge from Wisconsin through eastern Oklahoma
at 22Z will drift slowly east through the TAF period. VFR cigs and
flurries will dissipate this evening as the low level moisture field
pushes off to the southeast, with only scattered clouds at most for
the remainder of the forecast time frame. North to northwest winds
will drop to less than 7 kts by sunset 00Z and remain light through