839
FXUS63 KIND 111316
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
916 AM EDT Tue Jun 11 2024

.KEY MESSAGES...

- Sunny and Pleasant this afternoon

- Warming trend beginning Wednesday, highs near 90 for Thursday

- Chance of thunderstorms Thursday Night

- Potential for warmest temperatures of the year to go with high
  humidity starting Sunday

&&

.FORECAST UPDATE...
Issued at 916 AM EDT Tue Jun 11 2024

Surface analysis late this morning shows a large area of high
pressure in place over IL and IN.  The high was influencing the
weather from Ontario to the southern plains states. Cool and light
northwest flow remained across the forecast area and dew points were
in the pleasant lower 40s. Aloft a strong ridge of high pressure was
found stretching from KS to eastern WI and then northeast toward NW
Quebec. This was resulting in strong lee side subsidence across
Michigan and Indiana.

The upper ridge aloft is expected to drift east this afternoon.
Meanwhile at the surface, the well organized high pressure system
will remain in place across Central Indiana. Thus this will lead to
very little overall change this afternoon. Forecast soundings and
time heights show a dry column across Central Indiana through the
afternoon hours.  Thus a sunny afternoon is expected. The cool air
mass in place along with light north winds will allow for high
temperatures to only reach the middle 70s. Overall, ongoing forecast
is on track and only minor changes made to the ongoing forecast.

&&

.SHORT TERM (Today and tonight)...
Issued at 301 AM EDT Tue Jun 11 2024

Generally quiet weather expected today as high pressure resides over
the region. Surface winds should be fairly light today with variable
direction at times. Plentiful sunshine should allow temperatures to
rebound quite a bit from morning lows down into the 40s.
Temperatures in the mid to upper 70s are likely by the late
afternoon.

Thin cirrus begins to increase during the afternoon, however, as a
shortwave trough approaches from the northwest. Clouds thicken and
lower with time this evening perhaps becoming overcast from Indy
northward. There may be enough lift to generate a few sprinkles
across northern Indiana. Fairly dry air exists at the surface so
much of this activity would struggle to reach the ground. Still, if
anywhere were to see a sprinkle it would be across our northern
counties. Surface winds gradually turn southerly tonight as this
system passes through and the surface high moves eastward. This will
set the stage for a much warmer day Wednesday.

Low temperatures are likely to be a bit warmer Tuesday
night/Wednesday morning. A few reasons for this. First, the core of
the cold air mass exits eastward with the surface high. Second,
cloud cover and modest southerly flow act to limit radiational
cooling potential. Nevertheless, below-average readings are still
expected. The coolest lows may end up being across our south and
southeastern counties since winds will be lighter here and cloud
cover will be thinner. Lows in the low to mid 50s are likely across
much of the CWA.

&&

.LONG TERM (Wednesday through Monday)...
Issued at 301 AM EDT Tue Jun 11 2024

Wednesday Through Friday night.

The northwest flow regime will continue aloft through Friday night
which will keep it mostly dry. However, models are all keying in on
the potential for an MCS to move across central Indiana Thursday
night. Corfidi vectors favor a southeast moving complex. Weak
surface pressure gradient suggests low level inflow into the system
will be minimal, however 40-50 knot mid level jet and veering will
support good deep shear. Also, instability, although waning a bit
should still be plenty sufficient for thunder. At any rate, it is
much too early to diagnose mesoscale details, including cold
pool/shear balance but nonetheless the above reasoning supports at
least 30-40% PoPs Thursday night.

As the surface ridge aligns SW-NE along and south of the Ohio River,
temperatures will gradually warm to near 90 degrees by Thursday.
Meanwhile, potential cold front passage looks like it will result in
Friday being not quite as warm with timing considerations key.
Confidence is trending on the not as warm side.

Saturday Through Tuesday.

The main concern later in the weekend and next week will be the heat
and humidity as an upper ridge builds overhead and then shifts east
as southerly low level flow returns. Models are implying tropical
influx next week which will likely result in dew points approaching
70 degrees to go with afternoon highs in the 90s. With the increased
moisture and instability, can not rule out isolated pop ups either,
mainly during the afternoon.

This time period will need to the be looked at for potential future
headlines. For now, will broadbrush it in the HWO and keep a weather
story graphic going.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 618 AM EDT Tue Jun 11 2024

Impacts:

- No impacts expected

Discussion:

VFR conditions are expected through the period.

Winds maintain a northwesterly component through the day today
gradually becoming more westerly. Speeds remain under 10 knots. High
pressure directly overhead Tuesday night may allow for a period of
light and variable winds before a switch to southwesterly occurs
early Wednesday.

High clouds increase through the afternoon with perhaps some mid-
level clouds arriving after 00z. Clouds may become thick enough for
a ceiling to develop overnight. Mid-level clouds and perhaps a few
sprinkles are possible from IND northward. Skies begin clearing
Wednesday morning with some diurnal cumulus developing by the
afternoon.

Clearing skies with southwesterly winds 5-10kt are expected for
Wednesday.


&&

.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

UPDATE...Puma
SHORT TERM...Eckhoff
LONG TERM...MK
AVIATION...Eckhoff