Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 170755

Area Forecast Discussion
National Weather Service Louisville KY
255 AM EST Fri Nov 17 2017

.Short Term...(Today through Saturday)
Issued at 252 AM EST Fri Nov 17 2017

Low pressure over Wyoming today will become better organized and
stronger as it slides off the eastern slope of the Rockies and into
the central Plains. A deepening upper trof coming in behind the
surface reflection will allow the negatively tilted system to
continue to strengthen as it crosses the central and eastern United
States. The surface low will advance to central Illinois by Saturday
morning and Ohio by evening, dragging a sharp cold front through
southern Indiana and central Kentucky Saturday afternoon and early

The dew point surge ahead of this system will begin in earnest late
tonight and continue through Saturday ahead of the front, peaking in
the middle and possibly upper 50s. Precipitable water values will
rise to an inch tonight and around 1.25-1.50" Saturday.

Showers and a few thunderstorms will move in from the northwest
tonight, mainly after midnight, as the surface low proceeds from
Kansas to Illinois and meets up with the northward surging moisture.
Scattered showers and isolated thunderstorms will spread into the
rest of the region Saturday morning, and then become much more
widespread in the afternoon as the cold front barrels in.

Storms will mostly be elevated and should have a hard time mixing
down strong/severe winds to the surface. SB/ML/MU/DCAPE all look to
be weak and surface LI will be positive. The best chance of
strong/severe storms will be in a narrow corridor just ahead of the
cold front itself Saturday afternoon.

South winds will increase to 15-25mph after midnight tonight into
Saturday morning. Saturday afternoon winds will increase further,
especially with any showers/storms forced just ahead of the front.
The strongest synoptic winds of all should be post-frontal, coming
in from the west late in the afternoon and probably gusting to 45mph.

With strong WAA will go warmer than guidance for lows tonight.
Actually readings will likely increase a bit after midnight.
Temperatures on Saturday will peak in the mid 60s ahead of the front
and then fall precipitously behind it, into the mid 40s by 7pm in
southern Indiana and the upper 40s to low 50s in central Kentucky.


.Long Term...(Saturday night through Thursday)
Issued at 253 AM EST Fri Nov 17 2017

Winds will remain very gusty Saturday evening before lessening
toward Sunday morning. Could possibly see a few snowflakes north of
I-64 Saturday night.

The long term looks dry as Pacific high pressure crosses the
southeastern U.S., followed by a weak cold front that will have very
little moisture to work with Tuesday night, and then a Canadian high
coming in from the northwest Wednesday and Thursday.


.Aviation...(06Z TAF Issuance)
Issued at 1230 AM EST Fri Nov 17 2017

A blanket of stratus with bases 1000 to 1500 ft will move east to
west back across LEX and SDF, and eventually BWG over the next few
hours and then persist into the mid-morning hours. Latest guidance
hints at this cloud deck eroding/dissipating by mid-morning as the
moisture layer is very shallow. Once stratus lifts/erodes, winds
will become southerly throughout today, increasing this afternoon
and evening ahead of the next weather system.

A strong low-level jet sets up this evening and tonight and will
carry LLWS at all sites beginning this evening. 2000 ft winds will
be 45 to 50 kts out of the southwest. Showers may begin to move into
the HNB and SDF area after 04-06z.




Short Term...13
Long Term...13
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