269
FXUS63 KIND 171853
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
253 PM EDT Wed Jul 17 2024

.KEY MESSAGES...

- Scattered showers and isolated thunderstorms through this evening

- Very pleasant dry and mild weather expected from tonight at least
  through the weekend.

- Slightly more humid and unsettled weather begins to return next
  work week.

&&

.SHORT TERM (This evening through Thursday)...
Issued at 252 PM EDT Wed Jul 17 2024

Rest of Today...

Upper level analysis still shows a well established positively
tilted trough over northern Indiana, of which will continue to push
E/SE supported by moderate 850-700mb CAA. Out ahead of this trough,
modest instability below 400mb and the progression of weak surface
boundaries has allowed for scattered convective showers to develop.
Most of these showers will remain fairly weak, but latest ACARs
soundings should steady steepening of the mid level lapse rates
allowing for a few cells to reach 25kft and produce greater rainfall
rates and lighting. Brief 30-40mph gusts and pea sized hail cannot
be ruled out in these stronger storms, but most should remain weak
and short-lived.

Temperatures will continue to rise throughout the afternoon with
most locations along and south of I-70 reaching the mid 60s. A few
areas in northern central Indiana may fail to reach the low 80s if
cloud cover remains thick/overcast this afternoon.


Tonight and Tomorrow...

The parent boundary is currently over northern Indiana, and will
make its way through this evening into the early overnight. Behind
this boundary, surface dew points are much lower, removing the
rain/storm threat. Temperatures will also cool as a Canadian high
establishes over the Ohio Valley.

Winds will will also change directions as the parent boundary moves
through from W/NW to N/NNE. Winds should remain fairly constant
overnight between 5-7kts, but pockets of nearly calm conditions are
possible within close vicinity to the boundary. If any shallow
patchy fog were to develop tonight, it would be within these calmer
areas.

Tomorrow will be much cooler than usual with highs in the mid to
upper 70s. High pressure should help promote clear conditions
outside of some passing cirrus.

&&

.LONG TERM (Thursday night through Wednesday)...
Issued at 252 PM EDT Wed Jul 17 2024

The long term period late this week into the middle of next week
will be dominated by a fairly amplified large scale upper level
ridge/trough pattern from west to east across the CONUS. This will
provide a welcome break from the recent heat and humidity for the
majority of the period, especially through the weekend, which will
be nearly ideal for what is typically the hottest and most humid
time of year.

Thursday night will be the coolest night of the period, with lows in
the 50s across the entire area, with low 50s likely across northern
portions of the area by daybreak Friday. Temperatures will moderate
slightly as the period wears on, though this will be most noticeable
in the lows, as highs will generally remain near to just below
normal well into next week, but some gradual increase in the
dewpoints will help to prop up lows as we get into next week.

Modest chances for convection will return next work week as the
surface high gradually shifts eastward and weakens and some low
level moisture returns to the area, while the cooler air aloft
associated with the upper level trough provides potential for
destabilization. This would appear to be mostly diurnal in nature,
as there appears to be little in the way of support for organized
convection.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 657 AM EDT Wed Jul 17 2024

Impacts:

- Potential brief IFR/MVFR CIGs from generally VFR-level deck
  this morning
- VCSH through midday with isolated TSHRA possible south of I-70
- Winds veering to NNW by 20Z today...afternoon gusts to 13-16KT

Discussion:

Transition into northerly flow out of Canadian high pressure will
continue during TAF period.  Fair weather will prevail today between
widely scattered -SHRA...although with confidence in both rain, and
isolated VCTS, too low for any given location and time, have
maintained VCSH mention in TAFs.

Light winds early today will increase this morning while continuing
to veer through northwesterly directions...to NNW flow this
afternoon.  Winds will be sustained at 6-12KT with gusts to
13-16KT.

&&

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

&&

$$

SHORT TERM...Updike
LONG TERM...Nield
AVIATION...AGM