324
FXUS63 KIND 301544
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1144 AM EDT Sun Jun 30 2024

.KEY MESSAGES...

- Cooler and less humid Sunday and Monday
- Heat returns on Tuesday and Wednesday
- Rain/storm chances return Wednesday onward

&&

.FORECAST UPDATE...

- Mostly Sunny and pleasant this afternoon

Surface analysis late this morning shows strong high pressure in
place over MN. This high was extending its influence from Manitoba
and Saskatchewan, through the northern plains and building across
Indiana and Ohio. Northerly flow was in place across Central Indiana
and dew points had fallen to the upper 50s. Aloft, water vapor
showed ridging building across the Rockies with northwest flow
spilling from the upper Midwest to the Ohio Valley. Subsidence was
show in place over Indiana.

Ongoing forecast is in good shape. The high pressure system to the
northwest is expected to slowly build toward Indiana today. This
will result in continued ongoing subsidence and dry and cool
northerly winds. Forecast soundings suggest a dry column with a mid
level inversion, thus only some high clouds passing within the flow
aloft will be expected. Strong cold air advection is in place today.
850MB temps are expected to fall to near 12C by 00Z.  Thus expect
highs in the middle to upper 70s.

&&

.SHORT TERM (Today and tonight)...
Issued at 143 AM EDT Sun Jun 30 2024

Departing low-amplitude shortwave trough has nudged a cold front
into central Indiana with cooler/drier air now moving in. Much less
humid conditions are expected today with temperatures 10-15 degrees
cooler than 24-hours prior, about about 10 degrees below normal for
the end of June.

The subsident portion of the upper flow pattern leading to positive
MSLP anomalies will result in optimal radiative conditions tonight
and unusually cool temperatures for this time of year. Upper 40s to
low 50s are expected.

&&

.LONG TERM (Monday through Saturday)...
Issued at 143 AM EDT Sun Jun 30 2024

Monday and Monday Night...

Monday will be a continuation of the low amplitude surface ridge,
but with a slight uptick in 850-700mb dew points within easterly low
to mid level moisture advection. There should be enough elevated
moisture for isolated to scattered diurnal cu development Monday
afternoon, but otherwise conditions will be a carbon copy of Sunday
with a surface profile of around 80/50 across central Indiana. By
Monday night, winds will veer towards SE/S helping buoy overnight
lows, of which are expected to bottom out in the mid to upper 50s.

Tuesday Onward...

The next phase of the this pattern will arrive mid week, with broad
ridging developing aloft. By Tuesday, 850mb temps rise by about 5-10
degrees, which under full sun and efficient mixing corresponds to
highs in the mid to upper 80s. The primary axis of warm air will
then arrive Wednesday, with highs expected to be back into the 90s.
This upper ridge will continue to remain aloft keeping temperatures
above normal through the end of next week.

Even though upper level ridging will be in place across the Ohio
Valley, precipitation chances will still increase as a succession of
weak waves develop within broad upper level diffluence in the right
entrance region of the upper jet. This should lead to variable
thunderstorm chances Wednesday through Friday, until a frontal
boundary moves through late week, decreasing surface moisture.

The synoptic pattern is becoming much more consistently realized
within ensemble member, leading to greater confidence in generalized
hot and rainy stretch from Wednesday through Friday. However, the
finer details regarding specific timing and magnitude remain low as
there continues to be greater variance in surface wave location and
propagation speed.

Public Awareness Statement:

Storm chances exist before, during, and after the 4th of July
holiday. There is a chance that inclement weather interrupts holiday
plans. With that said, stay tuned for forecast updates as confidence
increases and we refine key details (timing, intensity, etc).

&&

.AVIATION (18Z TAF Issuance)...
Issued at 1144 AM EDT Sun Jun 30 2024

Impacts:

- VFR Conditions expected this forecast period

Discussion:

High pressure over the northern plains will build southeast across
central Indiana through this TAF period. Forecast soundings show a
dry column through the period. GOES16 shows some CU flowing across
the Wabash Valley this afternoon, but any brief cigs will be VFR at
HUF and LAF. This CU will rapidly deteriorate this evening as
heating is lost, leadingto clear skies through the rest of the TAF
period.

&&

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

$$

UPDATE...Puma
SHORT TERM...BRB
LONG TERM...Updike
AVIATION...Puma