963
FXUS63 KIND 271818
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
218 PM EDT Thu Jul 27 2017

.UPDATE...
The LONG TERM Section has been updated below.

&&

.SYNOPSIS...
Issued at 152 AM EDT Thu Jul 27 2017

A slow moving cold front from the northwest will cross Indiana from
today into Friday.  After that the same high pressure system should
dominate our weather well into next week. The center of this high ix
expected to be over the upper Great Lakes Friday evening, and
over the Appalachians by Tuesday.

&&

.NEAR TERM /Rest of Today/...

Issued at 956 AM EDT Thu Jul 27 2017

Have adjusted rain chances to reflect current and projected radar
data. Some areas did pick up 0.5 to 1.0 inch rains overnight but
nothing heavier and these were limited in coverage.

Limited instability and lack of shear are limiting very moist
atmosphere from generating widespread heavy rain for Indiana.
 Still expect scattered showers and as daytime heating
progresses, though limited, isolated thunder may still come into
play.

Though we don`t have far to go to reach 80, that may still be a
struggle given extensive cloud cover and the occasional showers.
Have kept max temps there for now but they may need a downward
adjustment to upper 70s at mid day update.

&&

.SHORT TERM (Friday through Saturday night)...

Issued at 152 AM EDT Thu Jul 27 2017

The main issue is the chance of rain Friday.

The models agree an unseasonably strong wave aloft will pass, but in
general have been struggling with precipitation forecasts lately.
MOS seems low considering the intensity of the system. The consensus
forecast will be used because that`s usually best in complex
situations, but confidence in Friday`s forecast is low. POPS may
need to be changed by 20 percent.

Beginning Friday night clear weather should develop as all models
take the wave aloft east of Indiana.

Confidence about Friday`s temperature forecast is low because of the
uncertainty about rain. A consensus will be used, with possible
errors of 4 degrees.  Confidence is higher about temperatures
Saturday and Saturday, with the models in alignment about cool high
pressure over Indiana. Consensus should be accurate to within 1-3
degrees.

&&

.LONG TERM /Sunday night through Thursday/...

Issued at 213 PM EDT Thu Jul 27 2017

Models are in good agreement on the upper pattern through much of
the long term. Have high confidence in dry weather Sunday night
through Wednesday before the pattern changes enough to allow the
next frontal system to approach. Medium confidence that high
pressure slides off to the east and allows a cold front to
approach and bring a return to at least small chances for
thunderstorms to end the week, but low confidence that this
happens before Friday. Stuck with the blended initialization low
pops for Thursday at this time. Temperatures appear to be near
normal through the period with highs in the mid 80s.

&&

.AVIATION /Discussion for 271800z TAFs/...

Issued at 1253 PM EDT Thu Jul 27 2017

Occasional MVFR ceilings and visibility during scattered showers
and isolated thunderstorms into early evening. With residual
atmospheric moisture, wet ground and light wind, widespread MVFR
conditions will develop around 280600z with areas of IFR ceilings.
Ceilings will lift after 281400z to VFR as drier air moves in.

Low pressure trough aligned east-west across central Indiana and
Illinois this afternoon will slowly settle south tonight and into
the Ohio Valley early Friday.

winds WSW south of the trough will veer to NNE after trough
passage but generally remain at or below 10 knots.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...JK
NEAR TERM...Tucek
SHORT TERM...JK
LONG TERM....CP
AVIATION...Tucek