Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 151855
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
255 PM EDT Tue Apr 15 2014
.SHORT TERM (Now through Wednesday Night)...
Issued at 310 PM EDT Tue Apr 15 2014
A hard freeze is expected tonight. A surface ridge now located along
the lower Missouri Valley will migrate east and will lie right over
the Commonwealth shortly after midnight. Skies will begin to clear
from west to east by late afternoon and will become almost
completely clear towards midnight.
Nearly ideal conditions for radiational cooling will allow lows to
fall into the mid 20s across many rural locations early tomorrow. In
more urbanized areas, expect lows in the upper 20s. Freezing
temperatures will linger well past dawn Wednesday.
The center of high pressure will move over New England Wednesday
afternoon, with an axis extending southwest over the Tennessee
Valley. Expect mostly clear skies Wednesday through early Thursday,
with light southeasterly winds. Wednesday will stay cool, with highs
only ranging from the mid to upper 50s. Lows Wednesday night will
fall well down into the mid to upper 30s.
.LONG TERM (Thursday through Tuesday)...
Issued at 300 PM EDT Tue Apr 15 2014
Thursday will be characterized by ridging over the southeast CONUS,
and developing low-level return flow as surface high pressure
retreats farther into New England. After a chilly (perhaps even
frosty) start, temps will recover to near seasonal normals.
Both northern and southern stream disturbances will move into the
eastern CONUS on Friday, but never quite seem to phase. ECMWF comes
closer to phasing the two streams than the GFS, but both point to
the distinct possibility that the Ohio Valley will be gapped by the
precip. Still looks like just enough forcing to squeeze out
scattered convection, but will limit the mention of thunder to a
slight chance and the QPF looks meager. Currently holding on to
slight chance POPs into Friday night, but with the models trending
toward a split between the northern and southern stream systems,
could easily end up dry.
Shortwave upper ridging will keep us dry over the weekend. Saturday
will be on the cool side with N-NE low-level flow, but rising
heights will put Sunday back above normal.
A progressive southern stream system will bring the next round of
precip to the Ohio Valley around Monday, but confidence in the exact
timing is limited. Rain is a pretty good bet somewhere between
Sunday night and Monday night, but timing is too uncertain to put
more than a chance POP in any given time period. Temps will trend
back on the high side of normal.
.AVIATION (18Z TAF Update)...
Issued at 110 PM EDT Tue Apr 15 2014
Surface ridging will pass over the Commonwealth late this evening.
Northwest winds averaging around 11kt with a few gusts to 20kt will relax
relatively rapidly this evening and become north around 5kt by
midnight. After becoming nearly calm during the pre-dawn hours,
expect light southeasterly winds Wednesday.
A broken deck of strato-cu with bases around 3k feet will continue
at LEX through around 19z before ceilings rise a bit. An isolated
sprinkle or light snow shower at LEX through 21z is possible.
Despite broken strato-cu at SDF and BWG, ceilings will continue VFR
for the rest of this afternoon. Clouds will scatter out by late
afternoon or early this evening and clear skies will continue
overnight and Wednesday.
KY...FREEZE WARNING from 9 PM EDT /8 PM CDT/ this evening to 11 AM
EDT /10 AM CDT/ Wednesday FOR KYZ023>043-045>049-053>057-
IN...FREEZE WARNING from 9 PM EDT /8 PM CDT/ this evening to 11 AM
EDT /10 AM CDT/ Wednesday FOR INZ076>079-083-084-089>092.