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fxus63 klmk 191417 
afdlmk

Area forecast discussion
National Weather Service Louisville Kentucky
917 am EST sun Feb 19 2017

..updated forecast discussion...

..Forecast update...
issued at 915 am EST sun Feb 19 2017

Updated forecast to increase sky cover, extend patchy fog and lower
highs today across the entire area.

12z soundings from iln, ilx, and ohx along with recent pilot weather reports and
GOES estimated cloud thicknesses indicate the stratus layer about
1500 to 2000 ft thick this morning across central Kentucky and
southern Indiana. Surface high pressure resides over central
Kentucky while the mid/upper ridge axis remains west along the MS
river. Hrrr and rap soundings hold onto the saturation in the low
level inversion through at least mid afternoon while the mid/upper
ridge axis slowly pushes east. Overall surface wind fields will be
very light as well. In short, think the stratus will linger longer
into the day so have trended forecast toward more mostly cloudy to
overcast. Subsequently, lowered highs 3-5 degrees, especially
along/east of I-65 where clouds are most likely to hang around. This
matches with some of latest guidance coming in showing highs in the
low/mid 60s. It's possible some areas around the Bluegrass may stay
below 60.

Area observations and webcams do show some patchy fog across parts of
the area, so extended that in the forecast a few more hours.

Issued at 628 am EST sun Feb 19 2017

The dense fog has mainly stayed to the west and south of the area
this morning with just occasional visibility drops to half a mile or
less. Have therefore decreased the fog wording in the grids to
patchy. In addition, some drizzle has been reported and can be seen
on radar. This was added into the forecast for the next few hours
across southern in and north central Kentucky.

Short term (now through monday)...
issued at 247 am EST sun Feb 19 2017

The axis of the upper level low has shifted east of the region
tonight. A few light rain showers or sprinkles may continue over
east central Kentucky for the next hour or two, but for the most part the
rain has ended.

The main concern for early this morning is the potential for fog
development. Areas of dense fog have formed west of the forecast
area across west central Kentucky and parts of southwestern in. The latest
mesoscale guidance continues to indicate this fog will spread
eastward over the next few hours. The primary area for fog looks to
be mainly along and north of the Ohio River. Will continue to
monitor webcams and observations and assess the need for a dense fog
advisory. If fog does form, it will likely linger into the
mid morning hours before mixing out.

Regardless of lower visibilities, the stratus deck looks to hang
around through the morning hours under an inversion. We should
finally start to see clouds break up by mid day or into the early
afternoon.

For tonight, surface high pressure will be centered to the northeast
of the region with ridging aloft. An inversion will again develop
with low level moisture remaining in place, particularly along and
north of the Bluegrass parkway. Some patchy fog may develop tonight
in this area.

Despite the clouds, we should see a decent warm up today with highs
in the mid to upper 60s. Highs for Monday will top out in the upper
60s to lower 70s.

Long term (monday night through saturday)...
issued at 304 am EST sun Feb 19 2017

Monday night will start out dry under the influence of the upper
level ridging. However, a shortwave and trailing front will begin to
approach the region early Tuesday. As this feature passes through on
Tuesday it will bring a chance for showers. Will continue to carry
50% or less chance for rain with this system.

Wednesday looks to be dry as we sit in between systems. By Thursday,
however, low pressure system will develop across the plains. A warm
front moving north across the region will bring another chance for
showers on Thursday.

Friday into Friday night the lower pressure system will move from
the Midwest into the Great Lakes region. Friday we look to be
solidly in the warm sector of this system with dewpoints rising into
the mid 50s and high temperatures in the mid 60s to lower 70s.
Soundings show an impressive wind field aloft and 500-1000j/kg cape.
Some strong storms could certainly be possible with this system.
Given how far out it is, a lot could change, but it does bear
watching this week. Behind the cold front, high pressure will build
in Saturday bringing dry weather.

Temperatures will remain well above normal through the work week
topping out in the mid 60s to lower 70s each day. Lows will
generally be in the mid 50s, warmer than the normal highs for this
time of year. We will see a sharp cool down on Saturday behind the
front with highs in the 50s and lows in the 30s Saturday and Sunday.

&&

Aviation (12z taf update)...
issued at 607 am EST sun Feb 19 2017

Low cloudiness and fog will be the main aviation issues at the
terminals early in the forecast period. Ceilings are expected to
run in the IFR range at the terminals this morning with mainly MVFR
vsbys. IFR vsbys will be likely at the beginning of the period at
kbwg. Conditions will slowly improve at the terminals by late
morning with some clearing developing in the afternoon hours. Kbwg
and ksdf look to mix out later this afternoon with perhaps low
clouds hanging on slightly longer over at klex. Winds today will be
light and variable.

Outlook for tonight, VFR conditions are expected. However, latest
19/06z guidance suggests that fog may become an issue early Monday
morning at all the terminal sites.

&&

Climate...
issued at 303 am EST sun Feb 19 2016

Record temperatures for the next few days.

Louisville: Fri. Feb. 17 record high:
sun. Feb. 19 record warm low: 56 (1882)
sun. Feb. 19 record high: 74 (1939)
Mon. Feb. 20 record warm low: 55 (1994)
Mon. Feb. 20 record high: 76 (2016)
Tue. Feb. 21 record warm low: 51 (1878)
Tue. Feb. 21 record high: 70 (1930*)
Wed. Feb. 22 record warm low: 61 (1922)
Wed. Feb. 22 record high: 71 (1992*)

Lexington:
sun. Feb. 19 record warm low: 50 (1971*)
sun. Feb. 19 record high: 75 (1939)
Mon. Feb. 20 record warm low: 54 (1994)
Mon. Feb. 20 record high: 72 (2016*)
Tue. Feb. 21 record warm low: 54 (1997)
Tue. Feb. 21 record high: 71 (1874)
Wed. Feb. 22 record warm low: 55 (1922)
Wed. Feb. 22 record high: 70 (1922)

Bowling green:
sun. Feb. 19 record warm low: 53 (1994*)
sun. Feb. 19 record high: 73 (1994*)
Mon. Feb. 20 record warm low: 55 (1994)
Mon. Feb. 20 record high: 75 (2014*)
Tue. Feb. 21 record warm low: 54 (1897)
Tue. Feb. 21 record high: 75 (1930*)
Wed. Feb. 22 record warm low: 55 (1961*)
Wed. Feb. 22 record high: 74 (1922)

Frankfort:
sun. Feb. 19 record warm low: 51 (1939)
sun. Feb. 19 record high: 76 (1939)
Mon. Feb. 20 record warm low: 47 (1949)
Mon. Feb. 20 record high: 73 (2016)
Tue. Feb. 21 record warm low: 47 (1906)
Tue. Feb. 21 record high: 72 (1997)
Wed. Feb. 22 record warm low: 49 (1935*)
Wed. Feb. 22 record high: 72 (1922)

* most recent occurrence, record occurred in previous years as
well

&&

Lmk watches/warnings/advisories...
Kentucky...none.
In...none.
&&

$$

Update.........Zt

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